Journal articles on the topic 'Seedling'
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1
Ekamawanti, Hanna Artuti, Lenawati Simanjuntak, and Abdurrani Muin. "Assessment of the Physical Quality of Eucalyptus pellita Seedlings from Shoot Cutting by Age Level." Jurnal Sylva Lestari 9, no. 2 (April 28, 2021): 280. http://dx.doi.org/10.23960/jsl29280-290.
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The criteria for target seedling of Eucalyptus pellita F. Muell are at least 90days old, with consequences for the length of stay of the seedlings in the nursery. This study must assess the suitability as a target seedling first if it wants to plant the seedlings under 90days old in the field. The research aimed to evaluate and obtain the regression equation for the seedling’s age with the seedling’s morphological characters. The shoot seedlings cuttings aged 45, 60, 75, and 90 days after planting in the cocopeat growing medium were assessed. The study was used a survey method with a purposive sampling technique to obtain 60 samples by assessing the growth and appearances of the seedling. Furthermore, 15 samples were taken at random to determine the dry weight of the seedlings. Seedlings aged 75 and 90 days indicated the standard criteria as target seedlings for height, diameter, number of leaves, seedling’s health, shoot appearances, and seedling roots. The two seedlings’age levels have a sturdiness index of 8.34-9.78; shoot-root ratio 3.9-4.5; and seedling quality index (SQI) 0.22-0.23. Seedling age had a powerful positive correlation with the sturdiness index and SQI (r = 0.84 and r = 0.96). The regression equation of the sturdiness index is y = 0.048x + 5.435 (R2 = 0.996) and SQI is y = 0.004x - 0.064 (R2 = 0.926). This research implies that 75 and 90-days seedlings can be considered as one of the criteria for the age of E. pellita shoot cuttings as the target seedling in the SOP of PT. Finnantara Intiga.Keywords: cocopeat, Eucalyptus pellita, Seedling Quality index, shoot cuttings, target seedling
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Wen, Yongshuang, Leian Zhang, Xuemei Huang, Ting Yuan, Junxiong Zhang, Yuzhi Tan, and Zhongbin Feng. "Design of and Experiment with Seedling Selection System for Automatic Transplanter for Vegetable Plug Seedlings." Agronomy 11, no. 10 (October 9, 2021): 2031. http://dx.doi.org/10.3390/agronomy11102031.
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In the process of vegetable plug seedling cultivation, packaging, and transportation, there may be missing, unhealthy or injured seedlings in the tray, which results in a missed planting or a low seedling survival rate after automatic transplanting. In this study, a seedling selection system with the function of seedlings identification, week seedlings elimination, and missing seedlings supplement was developed for an automatic transplanter. A plug seedling identification system based on a machine vision was used to detect vegetable plug seedlings based on the area characteristics of plug seedlings, stem leaves and plug bodies. The identification results were transmitted to a programmable logic controller (PLC), which controlled a nozzle to eliminate the unqualified seedlings from the conveyor belt lattice. When the empty conveyor belt lattice reaches the seedling throwing funnel, the rear conveyor belt lattice with the plug seedling is accelerated to ensure the continuity of seedlings supply. The adaptive fuzzy PID control algorithm was used to control the stepper motor of the conveyor belt to realize accurate seedling conveying and a seedling supplement. Using 30 days pepper plug seedlings as experimental seedlings, a comparative field experiment was carried out to evaluate the performance of the seedling selection system. The results showed that when the seedling selection system was turned on and the seedling extracting frequencies were 60, 80, and 100 plants/min, the success rates of plug seedling identification were 98.84%, 98.38%, and 96.99%, and the robust seedling rates were 98.05%, 97.78%, and 95.83%. The robust seedling rates were increased by 15.64%, 16.07%, and 13.89%, respectively, in contrast to turning off the seedling selection system.
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Reader, R. J., and J. Buck. "Control of seedling density on disturbed ground: role of seedling establishment for some midsuccessional, old-field species." Canadian Journal of Botany 69, no. 4 (April 1, 1991): 773–77. http://dx.doi.org/10.1139/b91-100.
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In midsuccessional old fields, seedlings are often concentrated in patches of disturbed ground, such as earth mounds created by burrowing mammals. An experiment was conducted to determine whether interspecific variation in seedling density on mounds reflected interspecific variation in potential seedling establishment (i.e., the number of seedlings established per 1000 seeds sown). Seeds of 13 old-field forbs were sown on experimentally created mounds in an abandoned pasture. Their potential seedling establishment ranged from 0 to 156 seedlings per 1000 seeds sown, and seedling establishment was directly related to seed mass. The number of seedlings becoming established naturally on mounds ranged from 0.1 to 41 seedlings per mound for the 13 species. Natural seedling establishment and potential seedling establishment were not directly related. Instead, natural seedling establishment on mounds was correlated with species' frequency of occurrence off mounds. This suggests that seed availability may be more important than seedling establishment in controlling seedling density on mounds. However, if seed availability is unlimited or equal among species, then seedling establishment could control seedling density on disturbed ground. Key words: disturbance, seedling density, old field.
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Reay, S. D., and P. J. Walsh. "A carbosulfan insecticide to protect pine seedlings from Hylastes ater (Coleoptera Scolytidae) damage." New Zealand Plant Protection 55 (August 1, 2002): 80–84. http://dx.doi.org/10.30843/nzpp.2002.55.3923.
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A controlled release granular carbosulfan pesticide was tested for efficacy against Hylastes ater damage of Pinus radiata seedlings in secondrotation forests in the central North Island Our study involved control seedlings and seedlings treated with 10 g or 15 g carbosulfan granules per seedling Seedling mortality ranged from 0 to 8 at the five sites When seedling mortality was high (8) mortality was reduced to 07 and 0 for carbosulfan granules applied at 10 g/seedling and 15 g/seedling respectively While seedling mortality in the five sites was low a large proportion of seedlings were damaged (38 to 83 of untreated seedlings) by H ater Untreated seedlings were damaged more frequently and with greater severity than treated seedlings The results indicate that that carbosulfan should protect P radiata seedlings from damage caused by H ater when used at the recommended field rate
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Lin, Jiaqi, Dongling Li, Zhenghui Pan, Dou Feng, and Weiyan Xuan. "Effect of the Floating Seedling Technique on Banana Seedling Growth." HortScience 57, no. 3 (March 2022): 458–63. http://dx.doi.org/10.21273/hortsci16303-21.
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Floating seedling technology was used to propagate banana seedlings. The effects of different substrates, such as wood bran, vermiculite, and Murashige and Skoog (MS) nutrient solution, at different concentrations on the survival rate of banana floating seedlings and the growth of seedling stem, leaf, and root systems were compared. The results showed that banana seedlings treated with MS nutrient solution at one-half or one-third concentration or hydroponically with controlled slow-release fertilizer (0.5–0.6 g/plant) directly added to the wood bran substrate grew the fastest and had the largest number of roots. At 50 days after transplanting, these banana seedlings reached the standard of first-grade packaged seedlings, with the number of expanded leaves reaching 6.6 to 7.6, the width of leaves reaching 6.5 cm to 7.3 cm, and the root system relatively developed. The comprehensive characteristics of the seedlings were all better than those of other treatments. The results of this study have certain reference significance for accelerating seedling growth in greenhouses and large-scale production of disease-free banana seedlings. The banana floating seedling system we developed did not need watering every day and may be simpler than other seedling raising methods.
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Li, Jinyang, Miao Zhang, Gong Zhang, Deqiang Ge, and Meiqing Li. "Real-Time Monitoring System of Seedling Amount in Seedling Box Based on Machine Vision." Agriculture 13, no. 2 (February 3, 2023): 371. http://dx.doi.org/10.3390/agriculture13020371.
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Conventional mat-type seedlings are still widely used in autonomous rice transplanters and automatically supplying seedling devices suited to conventional mat-type seedlings is difficult to develop. Thus, an autonomous rice transplanter carries at least one person to load the seedling pieces into the seedling box, which has led to an increase in the labor force and low operational efficiency. To solve this problem from another point of view, a machine vision-based system for the real-time monitoring of the seedling amount in a seedling box is developed. This system aims to achieve the monitoring of the fault of seedlings and seedling amount in the seedling box. According to the real-time and accuracy requirements of the image, the image acquisition platform is designed based on a previously developed autonomous rice transplanter. A camera model was developed and camera parameters for correcting the image distortion is obtained. The image processing method and segment method of seedling rows are presented. The algorithms for fault diagnosis and the calculation of the number of remaining seedlings are proposed by image analysis. The software is developed for seedling box fault diagnosis and monitoring the remaining number of seedlings. Field experiments are carried out to test the effectiveness of the developed monitoring system. The experimental results show that the image processing time is less than 1.5 s and the relative error of the seedling amount is below 3%, which indicates that the designed monitoring system can accurately realize the fault diagnosis of the seedling pieces and monitor for the remaining amount of each row. By combining the navigation information, the developed monitoring system can predict the distance from which the remaining seedlings in the seedling box can be planted, which can guarantee remaining seedlings in a seedling box are enough for transplanting until the rice transplanter returns to the supplying seedling site. This implies that one person can provide seedlings for multiple autonomous rice transplanters. This study was limited to supplying the seedling when the rice transplanter passed through the place of the seedling storage situated at the headland. In the future, we decide to conduct a study on path planning of breakpoint endurance so that the rice transplanter can automatically return to the supplying seedling place when the seedling amount in the seedling box is not enough.
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Herr, DG, LC Duchesne, R. Tellier, RS Mcalpine, and RL Peterson. "Effect of Prescribed Burning on the Ectomycorrhizal Infectivity of a Forest Soil." International Journal of Wildland Fire 4, no. 2 (1994): 95. http://dx.doi.org/10.1071/wf9940095.
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Ectomycorrhizae formation, seedling health index, and seedling survival were assessed for two-year-old nursery-grown seedlings of Pinus resinosa and Pinus strobus two months after planting in clear-cuts that had received prescribed burning under different fire intensities. Controls consisted of seedlings planted in unburned clear-cuts. Fire intensity positively correlated with percent ectomycorrhizal roots for P. strobus but not for P. resinosa. Seedling health index and survival were highest in burned-over sites as compared to control sites for both pine species. Fire intensity correlated with seedling health index for P. strobus but not for P. resinosa. Fire intensity correlated with seedling survival for both species. Colonization of seedlings by ectomycorrhizal fungi did not correlate with seedling health index or seedling survival. P. resinosa seedlings planted in burned-over sites had a smaller number of lateral roots per unit length primary/secondary roots compared to seedlings planted in control plots.
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Duchesneau, Robin, and Hubert Morin. "Early seedling demography in balsam fir seedling banks." Canadian Journal of Forest Research 29, no. 10 (October 1, 1999): 1502–9. http://dx.doi.org/10.1139/x99-090.
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Following the 1995 mast year, we conducted detailed seedling demography surveys to characterize some ecological factors affecting germination and early establishment in understory balsam fir (Abies balsamea (L.) Mill.) seedling banks and verify if recruitment from a cohort can potentially renew the balsam fir seedling bank. Twenty-five seed traps paired with 32 demography subplots were located in each of four permanent plots and regularly monitored over a 2-year period. Spatial patterns of newly emerged seedlings generally corresponded to those found for seed dispersal. However, at the end of the monitoring period, the spatial pattern of surviving seedlings was independent of the seed dispersal pattern. Seedbed types and understory light environments were the main factors explaining seedling mortality. Sphagnum mosses and decaying wood were the most favorable seedbeds for early establishment. The 0- to 25-cm seedling populations grew in size because of the addition of new recruits. If, in the years to come, mortality rates of the 1995 cohorts were similar to those of already established 0- to 25-cm seedlings, mast years of seed production, at least during endemic periods, would be crucial for recruitment and renewal of balsam fir seedling banks.
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Abdelmalik, Abdelmalik M. "Enhanced Growth and Drought Resistance in Seedlings of Acacia tortilis due to Inoculation of Arbuscular Mycorrhiza Fungi and Bacillus subtilis." International Journal of Agriculture and Biology 26, no. 06 (December 1, 2021): 750–60. http://dx.doi.org/10.17957/ijab/15.1891.
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A shade house experiment was conducted in Saudi Arabia to evaluate the impact of a mixture of three arbuscular mycorrhiza fungi (AMF) namely Funneliformis mosseae, Rhizophagus intraradices and Claroideoglomus etunicatum, a bacterium Bacillus subtilis, and their combinations on the growth and drought resistance potential of Acacia torilis seedlings under moderate and water deficit-stress. Thus, inoculants treatments (AMF, Bacillus subtilis, AMF+Bacillus, and control) and several watering intervals (1, 2, 3 and 4 weeks) were applied. Inoculation of AMF and Bacillus to A. tortilis seedlings found effective in terms of improved seedling growth. AMF and combined inoculation resulted in a larger shoot (shoot fresh and dry weights, seedling height, leaf number, leaf area) and root development (root fresh and dry weights, root length, root surface area, and root volume) as compared to the non-inoculated seedlings. Single inoculants of B. subtilis, showed better improvement in 1- and 2-week watering intervals compared to the control. Inoculated seedlings showed lower proline accumulation than non-inoculated seedlings, and thus improved seedling resistance to water deficit-stress. Mycorrhizal and mixed inoculation enhanced the amount of chlorophyll in the seedling’s leaves. Furthermore, seedlings with AMF and co-inoculants showed better drought tolerance even at 3- and 4-week watering intervals. © 2021 Friends Science Publishers
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Nurjaman, K. M., A. S. Wulandari, and Y. Istikorini. "Effect of Endophytic Fungi Inoculation and Ecoenzyme on the Growth of Gmelina (Gmelina arborea (Roxb.)) Seedlings." IOP Conference Series: Earth and Environmental Science 959, no. 1 (January 1, 2022): 012011. http://dx.doi.org/10.1088/1755-1315/959/1/012011.
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Abstract During the growth process, plants require nutrients and have a symbiotic relationship with beneficial microbes. The purpose of this study was to examine the effect of endophytic fungi inoculation and eco enzymes on the growth of Gmelina Seedlings. The endophytic fungi which were used were Ochroconis sp., Ascotricha sp., and Arthrinium malaysianum. Endophytic fungi inoculation into Gmelina Seedlings was carried out by watering fungal suspension onto the planting medium. The same method was carried out for the application of eco enzyme. The results showed that inoculation of the endophytic fungi A. malaysianum decreased the growth of Gmelina Seedling’s height and diameter. Inoculation of Ascotricha sp. decreased the growth of Gmelina Seedling height, and inoculation of Ochroconis sp. decreased the growth of Gmelina Seedling diameter. Endophytic fungi inoculation without eco enzymes could generate longer roots. As a result, shoot root ratio and seedling quality index showed that Gmelina Seedlings were ready to transplant in the field. The results of this study can be used as a reference in applying biological fertilizers to forestry plants.
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Moore, James A., Zhaofei Fan, and Bahman Shafii. "Effect of Root-Plug Incorporated Controlled-Release Fertilizer on Two-Year Growth and Survival of Planted Ponderosa Pine Seedlings." Western Journal of Applied Forestry 17, no. 4 (October 1, 2002): 216–19. http://dx.doi.org/10.1093/wjaf/17.4.216.
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Abstract Three controlled-release fertilizers (fast release [FR], moderate release [MR], and slow release [SR]) were incorporated in the root plug at rates of 0.8, 1.6, or 3.2 g/seedling at the time of sowing as supplements to nursery supplied soluble fertilizer. Effects on seedling growth, survival, and foliar nutrient status of the “160/90” container ponderosa pine (Pinus ponderosa) were evaluated after outplanting. At the end of the second growing season, fertilized seedlings had significantly greater diameter and height than unfertilized seedlings. The 3.2 g of MR or SR fertilizer treatments produced significantly higher mortality (55 and 36%, respectively) than the controls. The fast release fertilizer included at a rate of 0.8 g in each seedling's container was the preferred treatment since it produced good survival and seedling growth response. A 2-yr growth response of about 25% was similar to that observed in a nearby study using adjacent placement of controlled-release fertilizer after planting ponderosa pine seedlings. West. J. Appl. For. 17(4):216–219.
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Chen, Bin, Guangfa Hu, Songlin Sun, Mingtao Xiao, and Chaoran Sun. "Design and Experimental Study of Intermittent Automatic Grouping Dropping Plug Seedling Mechanism of Fixed Seedling Cups." Applied Sciences 12, no. 21 (November 2, 2022): 11125. http://dx.doi.org/10.3390/app122111125.
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In a vegetable transplanting operation, if the seedling picking mechanism extracts the whole row of seedlings, the seedling separating mechanism needs to place the seedlings in groups. In this study, a seedling separating mechanism based on a fixed seedling cup was proposed to realize faster seedling grouping in a smaller volume. A collision model between the pot and the wall of the seedling dropping cylinder during the seedling dropping process was established. The duration of seedling dropping at different positions was analyzed. Subsequently, the calculation equations between the installation angle and the cam rotation speed and the dropping duration were derived. The net dropping duration of seedlings at different positions was measured. According to the measurement results, the installation angles of the driving cam at each position were calculated as 0°, 72°, 150°, 216°, and 288°, respectively. The seedling uniformity test was conducted according to the optimized installation angles. The test results revealed that the success rate of dropping seedlings was 100%, the coefficient of variation in dropping seedling interval at different positions was 6.25%, and the matrix damage rate was less than 10%, which verified the reliability of the dropping seedling principle. Finally, the stability tests results showed that the mechanism was able to complete the uniform seedling drop operation at a seeding frequency of 75~108 plants/ (min · row) under the existing installation conditions. Therefore, the research results can provide a reference for the design and research of a subsequent traction-based automatic pot seedling transplanting machine.
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Sykes, SR. "Effects of seedling age and size on chloride accumulation by juvenile citrus seedlings treated with sodium chloride under glasshouse conditions." Australian Journal of Experimental Agriculture 25, no. 4 (1985): 943. http://dx.doi.org/10.1071/ea9850943.
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Chloride accumulation by juvenile citrus seedlings treated with sodium chloride for 56 days, using either nutrient solution culture (50 mM NaCl) or pot culture (75 mM NaCl) techniques under glasshouse conditions, was investigated in relation to seedling age. Ranking of cultivars on the basis of leaf chloride concentrations varied according to the age of seedlings examined. Leaf chloride concentrations of 6-, 5-, 4- and 3-month-old seedlings of eight cultivars examined in solution culture decreased with seedling age and were negatively correlated with seedling dry weight within some cultivars. Cultivar differences in leaf chloride concentrations, which occurred for all age groups, were negatively correlated with shoot growth and seedling dry weight for 5-month-old seedlings only. Leaf chloride concentrations of seedlings treated with NaCl in pot culture also changed with the age of seedlings (5, 17- and 29-monthsold) and varied between cultivars, with significant cultivar x age interactions. The effect of seedling size on chloride accumulation was investigated using nutrient solution culture. Six-month-old seedlings of four varieties were treated with NaCl (50 mM) for 56 days. Two size classes were obtained by growing seedlings at two densities before salt treatment. Small seedlings had greater shoot chloride concentrations than equivalent large seedlings and cultivar ranking, based on shoot chloride concentrations, changed with seedling size. Cultivar differences in leaf chloride concentrations were negatively correlated with seedling growth and dry weight for small seedlings but not for large seedlings. Seedling size had no effect on root chloride concentrations. The results suggest that screening very small seedlings for chloride exclusion is not feasible since rankings based on leaf chloride concentrations did not agree with documented data for grafted trees. There appeared to be a critical or threshold seedling age or size at or above which rankings for shoot chloride accumulation by good chloride excluders were consistent with documented field data. The results are discussed in relation to screening citrus hybrids for chloride exclusion under glasshouse conditions.
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Saito, Waka, Koji Kawamura, and Hiroshi Takeda. "Relative importance of overstory canopy openness and seedling density on crown morphology and growth of Acer nipponicum seedlings." Botany 90, no. 11 (November 2012): 1152–60. http://dx.doi.org/10.1139/b2012-079.
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We investigated the effects of overstory canopy openness and seedling density on seedling morphology and growth in the mid-successional species Acer nipponicum Hara in a cool-temperate forest. Studied seedlings were 46 seedlings of 30–160 cm height, and their overstory canopy openness ranged between 7.2% and 17.0%. Seedling density, measured as the number of conspecific neighboring seedlings within a 50 cm radius of the target seedling, ranged between 0 and 19. There were no significant correlations between seedling height, canopy openness, and seedling density. Multiple regression analysis showed that crown depth, leaf mass fraction, and leaf area index decreased with decreasing canopy openness and increasing seedling density, while the ratio of trunk-lateral branches mass increased. Overstory canopy openness did not affect crown area, leaf size, or petiole length, all of which decreased with increasing seedling density. Standardized regression coefficients indicated that seedling density affected morphology and growth more than canopy openness did. The morphological responses to canopy openness cannot be considered as adaptive plasticity, as total leaf area and leaf mass fraction decreased with decreasing light levels. In contrast, responses to seedling density indicate adaptive responses to neighborhood competition. The results highlight the importance of seedling density that influenced seedling growth and morphology independently of overstory canopy openness.
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Sun, Jingbin, Xueqiang Li, Shaochuan Li, Xiangyou Wang, and Linlin Wang. "Design Optimization and Experiment of Four-Row Potato Seedling-Cutting Machine." Applied Engineering in Agriculture 37, no. 6 (2021): 1155–67. http://dx.doi.org/10.13031/aea.14532.
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HighlightsBased on the innovative analysis of the seedling-cutting operation mechanism, five shapes of seedling-cutting blades were designed, and a four-row potato seedling-cutting machine was developed.The kinematics and mechanics of seedling-cutting blades were analyzed, which can provide a theoretical basis for the selection of experimental factors.A regression orthogonal experiment and variance analysis were carried out to verify the performance of the four-row potato seedling-cutting machine. Finally, the main and secondary factors affecting the seedling-cutting performance and the optimal parameter combination were obtained.Compared with other studies, the structure of the seedling-cutting blades are more complete in this study. The test results show that the qualified rate of the broken length of the potato seedlings is significantly improved, the missed cutting rate of the potato seedlings is reduced, and the length of the stubble is more uniform, which greatly improves the quality of seedling-cutting.Abstract. A four-row potato seedling-cutting machine was designed to address the problems associated with potato seedling-cutting machines with low qualified rates of broken length and stubble length and high missed cutting rates. Based on the analysis of the seedling-cutting operation mechanism, key components were designed, and the kinematics and mechanics were analyzed. A regression orthogonal experiment was carried out, taking the rotation speed of the seedling-cutting blade shaft, forward speed of the seedling-cutting machine, and height of the short blade of the ridge top from the ridge platform as the experimental factors and the qualified rate of the broken length of the potato seedlings, missed cutting rate of the potato seedlings, rate of carrying potatoes, and length of the stubble as experimental indexes. The results showed that the prioritized impact of various factors on the qualified rate of the broken length of the potato seedlings ranked as follows: the rotation speed of the seedling-cutting blade shaft > the height of the short blade of the ridge top from the ridge platform > the forward speed of the seedling-cutting machine. The prioritized impact of various factors on the missed cutting rate of the potato seedlings ranked as follows: the forward speed of the seedling-cutting machine > the rotation speed of the seedling-cutting blade shaft > the height of the short blade of the ridge top from the ridge platform. The prioritized impact of various factors on the rate of carrying potatoes and the length of the stubble ranked as follows: the height of the short blade of the ridge top from the ridge platform > the rotation speed of the seedling-cutting blade shaft > the forward speed of the seedling-cutting machine. The optimal parameter combination was a rotation speed of the seedling-cutting blade shaft of 1400 r/min, forward speed of the seedling-cutting machine of 4.22 km/h, height of the short blade of the ridge top from the ridge platform of 62 mm. Based on this combination, the qualified rate of the broken length of potato seedlings was 94.1%, the missed cutting rate of the potato seedlings was 0.30%, the rate of carrying potatoes was 0.49%, and the length of the stubble was 54 mm. The index values of the verification experiments were 94.6%, 0.38%, 0.53%, and 56 mm, which were better than the standard values, indicating that this machine meets the basic operation requirements. The test results can provide theoretical support and technical reference for improving the parameter and structural design of a potato seedling-cutting machine. Keywords: Field experiment, Flail blade, Potato, Seedling-cutting machine.
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Aizen, Marcelo A., and Hilary Woodcock. "Effects of acorn size on seedling survival and growth in Quercus rubra following simulated spring freeze." Canadian Journal of Botany 74, no. 2 (February 1, 1996): 308–14. http://dx.doi.org/10.1139/b96-037.
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Seed size is an important phenotypic trait commonly associated with the fitness of young seedlings exposed to environmental stress. Spring frosts can cause leaf necrosis and seedling mortality in young oak seedlings, and seedling mortality following spring freeze events is a factor limiting the northern range limits of Quercus gambelii (Nutt.). We examined the relationship between acorn size and seedling survival following spring freeze by exposing 1-month-old Quercus rubra (L.) seedlings from two sites in Massachusetts to −3 °C for 8 h. Mortality of 1-month-old frost-exposed seedlings (20–25%) was 10 times higher than control mortality, with survival directly related to acorn size. Seedling size at the end of the first growing season was negatively affected by frost exposure and positively associated with acorn size. Overwintering mortality (<5%) was negatively associated with seedling size. The production of large acorns should confer a selective advantage in habitats susceptible to spring frosts through a positive effect on seedling establishment success under stress. Keywords: red oak, acorn size, frost, seedling survival.
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Struve, Daniel, Petra Sternberg, Nick Drunasky, Kurt Bresko, and Rico Gonzalez. "Growth and Water Use Characteristics of Six Eastern North American Oak (Quercus) Species and the Implications for Urban Forestry." Arboriculture & Urban Forestry 32, no. 5 (September 1, 2006): 202–13. http://dx.doi.org/10.48044/jauf.2006.026.
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Seedling growth and water use of six North American oak species were studied in a series of four experiments to determine inter- and intraspecies water use characteristics. Xeric-site adapted species (chestnut oak, Q. prinus [L.] and black oak, Q. velutina [Lamb.]) had slower growth (height and dry weight accumulation and lower shoot:root ratios) than mesic-site adapted species (bur oak, Quercus macrocarpus [Michx.]; pin oak, Q. palustris [Muenchh.], northern red oak, Q. rubra [L]; and Shumard oak, Q. shumardii [Buckl.]). Principal component analysis (a statistical technique used to identify correlated variables) using 11 variables found that seedling water use loaded positively with seedling growth factors (taller seedlings tended to have higher dry weights and greater leaf and root areas and used more water than shorter seedlings, which tended to have lower dry weights, smaller leaf, and root areas) in the first principal component. However, in the third experiment, seedling growth factors loaded negatively with seedling water use for Q. prinus. Tall Q. prinus seedlings tended to use less water than short seedlings. However, other measures of water use (g water cm −1height and cm −2leaf and root area) loaded negatively on the first principal component. Correlations between seedling heights and seedling waters use were significant and positive, but great within-species and within half-sib family differences in height-adjusted water use (g water cm −1height) were found. By plotting height-adjusted water use against seedling height, efficient and inefficient water use seedlings could be identified. Inefficient water use seedlings were shorter and had higher water use cm −1height than efficient water use seedlings. Inefficient water use seedlings were described as having a xeric-water use habit, whereas tall seedlings had a mesic-water use habit. Potentially, height-adjusted water use could be used as a method for selecting individual oak seedlings better adapted to stressful urban planting sites.
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Suita, Eliya, Dede Jajat Sudrajat, and Nurhasybi Nurhasybi. "Growth of red sengon (Albizia chinensis (Osbeck) Merr.) seedlings on the molded seedling media and its comparison with polybag seedling." Jurnal Penelitian Kehutanan Wallacea 7, no. 2 (August 31, 2018): 141. http://dx.doi.org/10.18330/jwallacea.2018.vol7iss2pp141-149.
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The development of alternative methods for land and forest rehabilitation is necessary for producing good quality seedlings. This study aims to examine and compare the effect of addition of mycorrhiza and rhizobium on the growth of red sengon (Albizia chinensis (Osbeck) Merr.) seedlings in molded seedling media (BMSM) and the addition of various dosages of basic fertilizers to the seedlings on polybags. Seedlings in MSM were tested in the nursery until the age of 3 months. The field test was conducted by comparing the growth of red sengon (6 months after planting) seedlings from the BMSM and seedlings on polybags. The design used was a randomzed block design. BMSM that has been added with 3 g of rhizobium per seedling gave the best growth seedling and plant growth in the field. The growth of the seedling on polybags was increased by giving basic fertilizer of 5 kg per planting hole. Red sengon seedlings originated from seedling in BMSM with the addition of 3 g of rhizobium and seedlings on polybag with a dosage of 5 kg basic fertilizer had the highest growth. BMSM as an alternative technology for tree seedling production can be used for planting, and land or forest rehabilitation.
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Periasamy, Vivek, Duraisamy, and Kavitha. "Development of a picking and dropping mechanism for protray grown vegetable seedlings." Journal of Applied and Natural Science 13, SI (July 19, 2021): 47–54. http://dx.doi.org/10.31018/jans.v13isi.2776.
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In India, manual transplanting of vegetable seedlings was the commonly adopted method for raising vegetable crops, but it is laborious, time-consuming and costly. Therefore, mechanical transplanters are developed to overcome the problems in manual transplanting. The present work was to develop multiple seedlings picking and transferring mechanism for protray grown vegetable seedlings. Tomato (Solanum lycopersicum), chilli (Capsicum annuum) and brinjal (Solanum melongena) seedlings were raised in portrays with coir pith as a growth media and used for transplanting operation. The mechanism was to pick seven numbers of seedlings in one row at a time and transfer them into lateral conveying system, which could deliver the seedlings one by one on to the ground at regular interval. Programmable Logic Controller was used to controlling entire operations of seedlings picking and dropping. At the time of evaluation, a totally 196 number of seedlings were used with 98 cell protray. From the test results, the success rate of 89.28 per cent, missing seedling of 3.57 per cent, damaged seedling of 4.08 per cent, seedling delivering failure of 3.06 per cent were recorded for tomato seedlings. Similarly, in chilli and brinjal the success rate of 95.40 and 91.83 per cent, the missing seedling of 2.04 and 2.55 per cent, damaged seedling of 1.53 and 3.06 per cent and seedling delivering failure of 1.02 and 2.55 per cent respectively were observed. Transplanting frequency of developed mechanism was 2520 seedlings h-1. As a whole, this work was able to develop a working model of vegetable seedling transplanting mechanism, which can eject seven seedlings at a time from portray cell and transfer them into the slotted conveyor.
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Silva, Paulo S. D., Inara R. Leal, Rainer Wirth, Felipe P. L. Melo, and Marcelo Tabarelli. "Leaf-cutting ants alter seedling assemblages across second-growth stands of Brazilian Atlantic forest." Journal of Tropical Ecology 28, no. 4 (June 1, 2012): 361–68. http://dx.doi.org/10.1017/s0266467412000259.
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Abstract:Secondary forests promote an increased abundance of leaf-cutting ants (LCA) but the consequences on forest dynamics have been poorly addressed. Here we examine seedling assemblage attributes, seed germination and seedling survival across foraging zones of Atta cephalotes colonies inhabiting 15 second-growth patches (25–47 y old) of Atlantic forest. Seeds and seedlings were monitored within foraging zones and control sites over 1 y, including spots around ant nests. Overall, 1862 seedlings from 108 plant species were recorded. Seedling density decreased by 53% in foraging-zone plots (3.31 ± 0.23 seedlings m−2) when compared with control plots (7.02 ± 0.44 seedlings m−2) and a similar decrease was observed for species richness. Ant-induced alterations in the seedling assemblage were further indicated by segregation between foraging-zone and control plots (NMDS), habitat effects on species similarity (ANOSIM), and indicator tree species associated with control plots. While seed germination and seedling survivorship were uncorrelated to either nest distance or age of second-growth stands (with the exception of Tapirira guianensis), defoliation by LCAs was a significant cause of seedling mortality. Our results suggest that LCAs interfere with successional trajectories of Atlantic forest as foraging zones filter seedling establishment, supporting less-dense, impoverished and convergent seedling assemblages.
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Yücedağ, Cengiz, Nebi Bilir, and Halil Barış Özel. "Phytohormone effect on seedling quality in Hungarian oak." Forest Systems 28, no. 2 (July 4, 2019): e005. http://dx.doi.org/10.5424/fs/2019282-14604.
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Aim of study: to find out the effects of four phytohormones, including Indole Butyric Acid (IBA), Indole Acetic Acid (IAA), and Gibberellic acids (GA3, GA4) on seedling growth of Hungarian oak which has a natural distribution in the northwestern of Turkey.Area of Study: Mature acorns of Hungarian oak were collected from a natural stand in Zonguldak-Ereğli at northwestern region of Turkey.Material and Methods: Collected acorns of the species were pretreated with 300 ppm of each phytohormone for 24 hours and sown in Yenihan State Forest Nursery of Bartin, Turkey. Two years old bare-root seedlings were used for the measurements of seedling height, root collar diameter, stem, root and seedling fresh weights, and stem, root and seedling dry weights of two bare-root seedlings for each phytohormone treatment.Main results: Best performance of all studied seedling traits with the exception of root collar diameter was revealed in seedlings with IBA. In contrast, treatment of seeds with GA3 reduced all seedling traits apart from seedling height and root collar diameter. According to Dickson quality index, IBA was displayed to be the most beneficial phytohormone application for generating Hungarian oak seedlings with better mechanical resistance during transplanting.Research Highlights: IBA should be adopted in planting the seedlings of Hungarian oak for plantation activities.
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Ramasamy, P., Poonam Shinde, Sandip Ghate, and I. Sekar. "Economics of Nursery Nutrient Management for Bixa Orellana." Journal of Non-Timber Forest Products 21, no. 4 (December 1, 2014): 219–22. http://dx.doi.org/10.54207/bsmps2000-2014-658glh.
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An investigation was undertaken with Bixa orellana the test tree species to standardize ideal Integrated Nutrient Management (INM) techniques for improving the growth of B. orellana seedlings, so as to obtain the best quality seedling within a shortest nursery period. A nursery experiment was conducted by raising seedlings in polybags filled with standard soil mixture 2:1:1 (Soil: Sand: FYM) with three levels of nitrogen (100, 200 and 300 mg N per seedling) as urea, three levels of phosphorus (200, 300 and 400 mg P2O5 per seedling) as single super phosphate and three levels of potassium (100, 200 and 300 mg of K2O per seedling) as muriate of potash along with Farm Yard Manure (100g) per seedling, Azospirillum (5g) per seedling, Phosphobacteria (5g) per seedling and Vermicompost (5g) per seedling.The cost analysis revealed a positive trend in reducing the nursery period. The observation of this study showed that the production of 1000 seedlings in control incurred a total cost of Rs.800.00 and the seedlings took 120 days to reach a height of 24.10 cm, collar diameter of 0.65 cm and shoot-root ratio of 0.97 but the application of treatment T11 incurred Rs.1030.47 to produce the seedlings with same as that of control and it took 74 days only. Though the treatment T11incurred little bit higher cost than other treatments it produced good quality seedlings and also reduced the nursery period.In the present investigation, application of 200 mg of N, 300 mg of P2O5 and 200 mg of K2O along with Vermicompost (5g), Azospirillum (5g) and Phosphobacteria (5g) per seedling (T11) has produced healthy seedlings of 38.69 cm height in 74 days.
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Ren, Yun, Jianfang Zhu, Nazim Hussain, Shanlin Ma, Genru Ye, Dongqing Zhang, and Shuijin Hua. "Seedling age and quality upon transplanting affect seed yield of canola (Brassica napus L.)." Canadian Journal of Plant Science 94, no. 8 (November 2014): 1461–69. http://dx.doi.org/10.4141/cjps-2014-021.
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Ren, Y., Zhu, J., Hussain, N., Ma, S., Ye, G., Zhang, D. and Hua, S. 2014. Seedling age and quality upon transplanting affect seed yield of canola (Brassica napus L.). Can. J. Plant Sci. 94: 1461–1469. Seedling quality is an essential indicator for seed yield in canola, which is affected by many factors, including seedling age. Two field experiments were conducted to compare canola seedling quality and seed yield on 30-, 35-, 40-, 45-, 50-, 55-, and 60-d-old seedlings in 2011 and 2012. The relationship between seedling quality traits and seed yield of different seedling ages was also analyzed. Results revealed that the highest seed yield obtained from 40-d-old seedlings was attributed to more branches and siliques per plant. The negative effect of young seedlings (30-d-old) on seed yield was greater than that of old seedlings (60-d-old). The reduction rates in seed yield on the 30- and 60-d-old seedlings were 25.7 and 18.2%, respectively, compared with the 40-d-old seedlings. Increased root neck diameter, green leaf number, shoot, and root dry matter was the case on 40-d-old seedling transplanted plants compared with other ages. However, the increase was larger in the old seedlings than in the young seedlings. On average, the shoot and root dry weights of the 30-d-old seedlings were 1.9 and 1.7% of those in the 60-d-old seedlings. However, correlation analysis revealed that the seedlings with the highest shoot and root dry matter did not necessarily obtain the highest seed yield. Factor analysis suggested that the effects of root neck diameter and green leaf number on seed yield were more pronounced than those of shoot and root dry matter. Therefore, high seed yield in canola could be defined in terms of optimum green leaf numbers and branches per plant.
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Möhler, Henrike, Tim Diekötter, Geeltje Marie Bauer, and Tobias W. Donath. "Conspecific and heterospecific grass litter effects on seedling emergence and growth in ragwort (Jacobaea vulgaris)." PLOS ONE 16, no. 2 (February 2, 2021): e0246459. http://dx.doi.org/10.1371/journal.pone.0246459.
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Jacobaea vulgaris Gaertn. or common ragwort is a widespread noxious grassland weed that is subject to different regulation measures worldwide. Seedling emergence and growth are the most crucial stages for most plants during their life cycle. Therefore, heterospecific grass or conspecific ragwort litter as well as soil-mediated effects may be of relevance for ragwort control. Our study examines the effects of conspecific and heterospecific litter as well as ragwort conditioned soil on seedling emergence and growth. We conducted pot experiments to estimate the influence of soil conditioning (with, without ragwort), litter type (grass, ragwort, grass-ragwort-mix) and amount (200 g/m², 400 g/m²) on J. vulgaris recruitment. As response parameters, we assessed seedling number, biomass, height and number of seedling leaves. We found that 200 g/m² grass litter led to higher seedling numbers, while litter composed of J. vulgaris reduced seedling emergence. Litter amounts of 400 g/m² had negative effects on the number of seedlings regardless of the litter type. Results for biomass, plant height and leaf number showed opposing patterns to seedling numbers. Seedlings in pots treated with high litter amounts and seedlings in ragwort litter became heavier, grew higher and had more leaves. Significant effects of the soil conditioned by ragwort on seedling emergence and growth were negligible. The study confirms that the amount and composition of litter strongly affect seedling emergence and growth of J. vulgaris. Moreover, while conspecific litter and high litter amounts negatively affected early seedling development in ragwort, those seedlings that survived accumulated more biomass and got taller than seedlings grown in heterospecific or less dense litter. Therefore, ragwort litter has negative effects in ragwort germination, but positive effects in ragwort growth. Thus, leaving ragwort litter on pastures will not reduce ragwort establishment and growth and cannot be used as management tool.
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Oshima, Chiaki, Yuji Tokumoto, and Michiko Nakagawa. "Biotic and abiotic drivers of dipterocarp seedling survival following mast fruiting in Malaysian Borneo." Journal of Tropical Ecology 31, no. 2 (December 16, 2014): 129–37. http://dx.doi.org/10.1017/s026646741400073x.
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Abstract:South-East Asian tropical rain forests experience sporadic, but profuse, seed production after general flowering, leading to the synchronous emergence of various seedlings and subsequent seedling dynamics, which play a crucial role in determining species distribution and coexistence. We examined the relative importance of both biotic (initial height, conspecific seedling density) and abiotic (canopy openness, per cent sand, soil water content) drivers using survival data for 1842 seedlings of 12 dipterocarp species for 1.5 y following mast fruiting in an old-growth Bornean tropical rain forest. More than 30% of all dipterocarp seedlings survived 1.5 y after mast fruiting. When all species were analysed together, we found that initial seedling height, canopy openness and conspecific seedling density affected dipterocarp seedling survival. Negative density dependence indicated that predators were not satiated, but dipterocarp seedlings rather suffered from host-specific natural enemies or intraspecific competition. Species-level analyses of seven dipterocarp species showed large variation in response to biotic and abiotic factors. These results suggest that interspecific differences in the relative importance of biotic and abiotic effects on seedling survival might contribute to species coexistence.
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Erniwati, Erniwati. "PENGARUH UKURAN BIJI TERHADAP KEMAMPUAN TANAMAN TUMBUH KEMBALI SETELAH RUSAK AKIBAT HERBIVORI." Jurnal Ilmu-Ilmu Pertanian Indonesia 9, no. 2 (December 4, 2017): 156–64. http://dx.doi.org/10.31186/jipi.9.2.156-164.
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The objective of the study is to investigate the effect of seed size in the resprouting ability of seedling after being damaged and whether it correlates with the reserve effect. We grew the seedlings of two species of oak, namely Quercus robur and Quercus petraea from different seed size, in a greenhouse. The seedlings were harvested at different stages; after emergence, at the first shoot fully developed, and after the seedling had re- grown after the initial shoot was clipped. The result showed that: firstly, at the time of full seedling development, large seeds translocated less percentage of reserve from the seed to seedling. After clipping, the seedlings from large seeds translocated additional resources to the seedling. Secondly, although the larger seed has the larger biomass to re-sprout, the total mass invested in re-sprouting proportional with seedling size. We concluded that the seedlings of larger seeds re-sprout better than those of the smaller seeds. However, we did not find the improved performances correlating with the Reserve Effect Theory
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S.H.S. Senarathne. "Effect of Arbuscular Mycorrhizal Fungi Based Biofertilizer on Coconut Seedlings Growth in Nursery." CORD 34, no. 2 (April 1, 2018): 12. http://dx.doi.org/10.37833/cord.v34i2.17.
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The success of a coconut plantation, in terms of its field establishment as well as its future performance, is heavily dependent on the quality of the seedlings used. Coconut nurseries adopt different agronomic practices to produce good quality seedlings. Applying mycorrhizal inoculants is becoming an increasingly common practice in plant nurseries as it facilitates healthy seedling growth resulting in healthy and vigorous seedlings in the nursery, helps to reduce mortality rates of seedlings in the field and reduce water and fertilizer consumption. In this study effects of mycorrhizae based biofertilizer were evaluated for the growth of coconut seedlings in the nursery and field. The experiment was conducted at the Makadura Research Center in Sri Lanka. The nursery experiment treatments were, the presence of AMF based biofertilizer (50g per seedling or per bag) and absence of mycorrhizae based biofertilizer. In the field experiment, five treatments with 500g of AMF biofertilizerwith 25% recommended inorganic fertilizer mixture for young coconut palms (YPM) per seedling, 500g of AMF biofertilizer with 50% YPM per seedling, 500g of AMF biofertilizer with 75% YPM per seedling, 500g of AMF biofertilizer with 100% YPM per seedling and with only YPM per seedling. Root and shoot growth of seedlings were measured at monthly intervals in the nursery experiment. Leaf production rate and stem girth of the seedling were measured at six months interval in the field experiment. The application of bio fertilizer increased the volume and dry weight of primary, secondary, tertiary and quaternary roots in seedlings in the nursery significantly. A significantly higher leaf production rate and stem girth was observed in the field seedlings treatment with 500g of AMF biofertilizer with 75% YPM. The experiment concluded that application of bio fertilizer is beneficial for coconut seedlings in the nursery for the production good quality seedlings with well-developed roots resulting in better field establishment and in the field for fast and vigorous growth.
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Santos, Gildomar Alves dos, David Francis Robert Philip Burslem, Milton Serpa de Meira Jr, and Stanislau Parreira Cardozo. "Introduction of native tree species into degraded Cerrado vegetation." Interação 21, no. 2 (June 30, 2021): 61–84. http://dx.doi.org/10.53660/inter-102-s127.
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Experimental restoration using tree seedlings is a common strategy for accelerating succession on degraded post-agricultural land formerly occupied by Cerrado vegetation. Seedling growth in degraded tropical lands is constrained by various factors. The goal of this study was to evaluate the seedling growth and survival of seven native tree species used to accelerate forest recovery in a gully area with stressful environmental conditions. The experimental design involved fenced and unfenced blocks, presence and absence of fertilization and use of an adhesive to prevent ant herbivory (four treatments with four replicates). Seedlings were planted in December 2006 and collection of data on seedling basal diameter, height, mortality and herbivory started on January 24th 2007 and continued every three months, until final data collection on January 31st 2009 (9 measurement dates). Overall seedling survival was 38 % and protecting seedlings did not influence growth, but seedlings grew faster in response to the addition of fertilizer containing N, P and K. The use of the adhesive Tanglefoot to exclude leaf cutter ants had no influence on growth. Fencing reduced seedling mortality, but combining fencing with Tanglefoot did not. Nutrient availability limits seedling growth and survival in the gully. Direct planting of seedlings of native trees may accelerate succession in degraded Cerrado lands subject to interventions that overcome constraints on seedling growth and survival.
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Marler, Thomas E., and April N. Cascasan. "Number of emerged seedlings and seedling longevity of the non-recruiting, Critically Endangered Håyun lågu Tree Serianthes nelsonii Merr. (Fabales: Leguminosae) are influenced by month of emergence." Journal of Threatened Taxa 7, no. 15 (December 26, 2015): 8221. http://dx.doi.org/10.11609/jott.2100.7.15.8221-8225.
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<p>Emergence and longevity of seedlings beneath Guam’s only known Håyun lågu Tree <em>Serianthes nelsonii</em> were studied to determine the fate of every observed seedling during 2013. Newly emerged seedlings were marked with wire stakes every 15 days, then the stakes were collected at each seedling upon death. Longevity of each seedling was calculated from the marked ending and emergence dates. The least number of newly emerged seedlings was recorded at the end of the dry season, and the greatest number of newly emerged seedlings was recorded in the beginning of the rainy season. More than half of the year’s 374 seedlings died in less than 30 days. Seedling longevity ranged from a mean of 31 days for seedlings that emerged in May to 78 days for seedlings that emerged in June. Our results reveal that the baseline level of recruitment potential of the lone survivor of this species on Guam is substantial, and underscore the need for further research to determine the factors associated with the acutely limited seedling lifespan.</p><div> </div>
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Vasconcelos, Heraldo L., and J. Malcolm Cherrett. "Leaf-cutting ants and early forest regeneration in central Amazonia: effects of herbivory on tree seedling establishment." Journal of Tropical Ecology 13, no. 3 (May 1997): 357–70. http://dx.doi.org/10.1017/s0266467400010567.
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ABSTRACTThe effects of herbivory by the leaf-cutting antAtta laevigataFr. Smith on the re-establishment of forest trees in an abandoned farm near Manaus, central Amazonia, were investigated. Experimental seedling transplants and observations on seedlings which emerged naturally in the study area showed that damage by leaf-cutting ants negatively affected tree seedling survival and growth. However, excluding leaf-cutting ants from experimental plots for 20 mo did not significantly increase tree seedling densities. The number of seedlings emerging varied considerably between plots and this obscured any effect the ants may have had on seedling survivorship. Taller seedlings, and seedlings attacked only once, suffered less mortality than smaller seedlings and seedlings attacked twice or more. In general, mortality was greater for those species preferred by the ants, indicating that selective herbivory by leaf-cutting ants affects tree species composition. The number of seedlings attacked byA. laevigataremained approximately constant throughout the period of this study in spite of the fact that the number available for attack increased. Thus, the chance of any individual seedling being attacked declined with time, suggesting that the effect ofAttaherbivory on tree establishment is stronger during the first few years of forest regeneration.
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Oka, Chihiro, Tomoyuki Itagaki, and Satoki Sakai. "Effects of the number of embryos in a seed and seed mass on seedling survival and growth in polyembryonic Ophiopogon japonicus var. umbrosus (Asparagaceae)." Botany 94, no. 4 (April 2016): 261–68. http://dx.doi.org/10.1139/cjb-2015-0214.
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Research on polyembryony suggests that the presence of multiple embryos in a seed confers an advantage for seedling survival. Because observations from embryo to seedling stages are lacking, however, the effect of the exact number of embryos on seedling survival is unclear. In this study, we evaluated the effect of seed embryo number on seedling survival and growth to determine the number of embryos in a seed that are advantageous for seedling survival in Ophiopogon japonicus (Thunb.) Ker Gawl. var. umbrosus Maxim., which is a taxon exhibiting cleavage polyembryony. We also investigated whether seed mass affects seed embryo number and seedling survival and growth. We found that the number of embryos in seeds of O. japonicus var. umbrosus was weakly dependent on seed mass. As the number of embryos increased, the number of seedlings surviving from seeds initially increased and then decreased; the greatest number of seedlings was produced from an intermediate number of embryos, with the number of embryos producing the greatest number of seedlings increasing with seed mass. The sum of individual seedling lengths increased with the number of seedlings. Our results indicate that an intermediate number of embryos may be advantageous in polyembryonic O. japonicus var. umbrosus.
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Conner, Patrick. "Effect of Nitrogen Fertigation on First-year Pecan Seedling Growth." HortTechnology 17, no. 4 (January 2007): 491–95. http://dx.doi.org/10.21273/horttech.17.4.491.
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Pecan (Carya illinoinensis) seedling rootstocks require several years of growth in the nursery before they are large enough to graft. In this experiment, first-year pecan seedlings were fertigated with varying amounts of calcium nitrate in an attempt to stimulate growth rates. Pecan seedlings were fertigated every 2 weeks from May through October for a total of 10 applications. Total amounts of nitrogen (N) applied by fertigation were 0, 4, 10, 20, and 40 g of N per seedling. Leaf samples were taken after the fourth and tenth fertigations, and leaf elemental concentration was affected by fertigation rates. Seedling height and caliper were measured monthly. Seedling caliper continued to increase throughout the experiment, whereas height increase stopped in September. Seedling height and caliper were unaffected by N fertigation except for the N rate of 40 g, which suppressed seedling growth. These results suggest that the N needs of the seedlings were met by a preplant application of 50 lb/acre N applied as 10N–4.4P–8.3K.
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Conner, Patrick. "(130) Effects of Nitrogen Fertigation on First-year Pecan Seedling Growth." HortScience 41, no. 4 (July 2006): 1062D—1062. http://dx.doi.org/10.21273/hortsci.41.4.1062d.
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Pecan seedling rootstocks require several years of growth in the nursery before they are large enough to graft. In this experiment, first-year pecan seedlings were fertigated with varying amounts of calcium nitrate to stimulate growth rates. Pecan seedlings were fertigated every 2 weeks from May through October for a total of 10 applications. Total amounts of nitrogen (N) applied by fertigation were 0, 4, 10, 20, and 40 g of N per seedling. Leaf samples were taken after the fourth and 10th fertigation, and leaf elemental concentration was affected by fertigation rates. Seedling height and caliper were measured monthly. Seedling caliper continued to increase throughout the experiment, while height increase stopped in September. Seedling height and caliper were not affected by N fertigation except for the N rate of 40 g, which suppressed seedling growth. These results suggest that the nitrogen needs of the seedlings were met by a preplant application of 56 kg·ha-1 N applied as 10N–10P–10K.
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Castro, Jorge, and Alexandro Leverkus. "Effect of Herbaceous Layer Interference on the Post-Fire Regeneration of a Serotinous Pine (Pinus pinaster Aiton) across Two Seedling Ages." Forests 10, no. 1 (January 20, 2019): 74. http://dx.doi.org/10.3390/f10010074.
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Herbaceous vegetation is a major source of interference with the regeneration of woody species. This is particularly the case after forest fires, as a dense herbaceous layer usually regenerates naturally. Although the competitive effect of the herbaceous vegetation upon tree seedlings has been widely studied, there are still gaps in knowledge for management related to the effect of tree seedling age and size on the outcome of the interaction. In this study, we seek to determine the response of maritime pine (Pinus pinaster Aiton) seedlings to herbaceous competition at two different seedling ages. For that, two treatments of herbaceous competition were implemented, namely unweeded (no action around pine seedlings) and weeded (herbaceous cover removed around pine seedlings). Treatments were conducted twice (2 and 4 years after the fire), and we monitored seedling survival and growth at the end of each growing season. The treatments were implemented across three adjacent landscape units that differed in the management of burned wood and that are representative of common post-fire scenarios: no intervention, salvage logging, and an intermediate degree of intervention. Weeding increased seedling survival from 44.7% to 67.8% when seedlings were 2 years old, but had no effect for four-year-old seedlings, which showed 99% survival. Seedling growth also increased in the weeding treatment, but only slightly. Moreover, growth (and survival for two-year-old seedlings) was strongly correlated with initial seedling size, particularly in the case of two-year-old seedlings. Initial pine seedling height was strongly and positively correlated with the height of the herbaceous layer, supporting the existence of microsite features that promote plant growth above competitive effects. The results support that management actions conducive to foster post-fire pine forest restoration in this Mediterranean ecosystem should reduce herbaceous competition at early stages after fire (second or third year) and focus on larger seedlings.
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Hu, Fan, Xuan, Mgelwa, and Chen. "Distinct Growth and Nutrient Status Responses to Fertilization Regimes in Two Generations of Chinese Fir Seedlings." Forests 10, no. 9 (August 21, 2019): 719. http://dx.doi.org/10.3390/f10090719.
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Exponential fertilization is well-known for improving the growth and nutritional status of seedlings during nursery culture. However, less is known about how genetic variability among seedling species influences the effects of fertilization regimes on the growth of seedlings and their nutritional status under varying fertilization levels. Here, we conducted a greenhouse experiment to compare the growth, as well as the nitrogen (N) and phosphorus (P) nutrient concentration responses, of 2- and 3-generation Chinese fir (Cunninghamia lanceolata (Lambert) Hooker) seedlings to the impacts of varying exponential and conventional constant-rate fertilization levels (50, 100, and 200 mg P seedling−1). Seedling size and shoot:root ratios were lower in exponential fertilization than in conventional fertilization. Exponentially fertilized seedlings had higher concentrations of N and P nutrients compared to conventionally fertilized seedlings during low-level fertilization. Conversely, an elevated P concentration was observed in seedlings subjected to conventional fertilization compared to those exposed to exponential fertilization during high-level fertilization. However, there were no significant differences in seedling N and P concentrations between the two fertilization regimes during medium-level fertilization. Furthermore, 2- and 3-generation Chinese fir seedlings differed greatly in their growth and nutritional status. Additionally, there were significant fertilization regime × seedling generation interaction effects on the seedling shoot:root ratio and N concentration. Our findings suggest that exponential fertilization can improve the nutritional status, survival, and growth of Chinese fir seedlings, especially on competitive sites, and that information on both intra-species genetic variability and appropriate fertilizer levels is necessary for the successful fertilization of Chinese fir seedlings, regardless of fertilization regimes.
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Boyer, James N., David B. South, Carl Muller, Harry Vanderveer, Walter Chapman, and William Rayfield. "Speed of Germination Affects Diameter at Lifting of Nursery-Grown Loblolly Pine Seedlings." Southern Journal of Applied Forestry 9, no. 4 (November 1, 1985): 243–47. http://dx.doi.org/10.1093/sjaf/9.4.243.
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Abstract Speed of germination affects seedling quantity and quality. This study investigated the effect of germination speed on loblolly pine (Pinus taeda) seedling diameter at lifting. Studies were installed at three forest nurseries in Alabama to test the effects of stratification treatments on speed of germination and of seedling emergence date on final seedling diameter. Results varied with the length of stratification employed. However, in all cases, seedlings which emerged earliest (first 40%) attained significantly larger diameters than seedlings from seeds which germinated later.¹
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Fu, Wei, Jinqiu Gao, Chunjiang Zhao, Kai Jiang, Wengang Zheng, and Yanshan Tian. "Detection Method and Experimental Research of Leafy Vegetable Seedlings Transplanting Based on a Machine Vision." Agronomy 12, no. 11 (November 20, 2022): 2899. http://dx.doi.org/10.3390/agronomy12112899.
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In view of the need to remove empty cells and unqualified seedlings for automatic transplanting of leafy vegetable seedlings, this paper proposes a method to detect the growth parameters of leafy vegetable seedlings by using machine vision technology. This method uses the image processor PV200 to perform image grayscale, threshold segmentation, corrosion, expansion, area division, etc. to obtain the pixel value of the leaf area of the seedling and compare it with the set standard value, which provides guiding information for eliminating empty cells and unqualified seedlings. Lettuce seedlings at 17 days, 20 days, and 22 days of seedling age were used as the test objects, and the growth status and test results of the seedlings were analyzed to determine the optimum seedling age for transplanting. The test results show that there is basically no leaf cross-border between the lettuce seedlings at the age of 17 days, the average pixel area of the leaves is 3771.74, and the detection accuracy rate is 100%; the seedlings at the age of 22 days grow 5–6 leaves, the detection accuracy of unqualified seedlings and qualified seedlings was 62.50% and 88.16%, respectively, and the comprehensive detection accuracy was 85.71%. The comprehensive detection accuracy rate showed a downward trend with the increase of seedling age, mainly due to the partial occlusion between leaves. The transplanting of leafy vegetable seedlings is a sparse transplanting operation, and the seedling spacing increases after transplanting. Therefore, the detection of seedlings in the process of transplanting can greatly improve the recognition accuracy and solve the problem that the leaves of the seedlings in the seedling tray are obscured by each other and affect the detection accuracy. The research results can provide a theoretical basis and design reference for the development of the visual inspection system and the transplanting actuator of the leafy vegetable seedlings transplanting robot.
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Yang, Chuan Hua, Xian Fa Fang, Xin Jin, Zhong Jun Liu, Jun Liu, and Yu Hui Guo. "Motion Analysis for Vegetable Potted Seedling Pick-Up Mechanism with Double Crank Geared Linkages." Applied Mechanics and Materials 529 (June 2014): 218–23. http://dx.doi.org/10.4028/www.scientific.net/amm.529.218.
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The semi-automatic feeding mechanism of vegetable transplanter was nacelle basket type which is available with manual feeding for transplanting vegetable potted seedlings. However, the efficiency is lower to meet the needs. To improve it, a new design of the potted seedling pick-up mechanism with double crank geared five-bar linkages model was expounded for automatic seedling picking. The kinematics model of the pick-up mechanism was established by mathematical analysis method. The influence of the structural parameters on the motion trajectory and relative velocity of the seedling pick-up arm cusp was investigated. The design of optimization objective for picking vegetable potted seedling was proposed. Meanwhile, the optimal parameter combination of the pick-up mechanism was obtained by using MATLAB based on the objective. With it, when the seedlings pot were being pulled out, the path of the seedling pick-up arm inserting was straightly and more perpendicular to potted seedling. Furthermore, the velocity of seedling taking and dropping cusps were relatively lower in order to meet the speeds demand of seedling picking up with seedling feeding in automatic way.
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Roe, Nancy E., Peter J. Stoffella, and Donald Graetz. "Composts from Various Municipal Solid Waste Feedstocks Affect Vegetable Crops. I. Emergence and Seedling Growth." Journal of the American Society for Horticultural Science 122, no. 3 (May 1997): 427–32. http://dx.doi.org/10.21273/jashs.122.3.427.
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The composition of composts derived from municipal solid wastes can affect emergence and seedling growth. Composts consisting of biosolids and yard trimmings [standard compost (SC)] alone or with mixed waste paper (MWP), refuse-derived fuel (RDF), or refuse-derived fuel residuals (RDFR) were evaluated in seedling trays and pots for vegetable crop seedling emergence and growth. In trays, tomato (Lycopersicon esculentum Mill.), cucumber (Cucumis sativus L.), and pepper (Capsicum annuum L.) seedlings emerged faster from a commercial peat-lite mix and from sandy field soil than from the composts. Plants were tallest and shoots were generally heaviest in the peat-lite mix and aged SC and smallest in the field soil. MWP compost generally inhibited early seedling growth more than RDF or RDFR composts. Among the composts, seedlings were tallest and heaviest in SC. In pots, growth of each vegetable was generally greatest in SC, followed by other composts, and lowest in sandy soil. Tomato and pepper seedling emergence was more sensitive to the inhibitory effects of the RDF, RDFR, and MWP composts than cucumber seedling emergence. Fertilizer increased plant growth in each medium except SC, in which cucumber stem diameter was not increased. Adding MWP, RDF, or RDFR to SC generally decreased seedling emergence and growth. The composts prolonged days to emergence and decreased percent emerged seedlings. However, subsequent seedling growth in composts was equal to or greater than seedlings in the peat-lite mix and much greater than those in the sandy field soil.
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GUBBELS, G. H., and E. O. KENASCHUK. "EFFECT OF SPRING SEEDLING RESIDUES ON THE AGRONOMIC PERFORMANCE OF SUBSEQUENT FLAX AND BARLEY CROPS SEEDED WITH AND WITHOUT PRIOR TILLAGE." Canadian Journal of Plant Science 69, no. 1 (January 1, 1989): 151–59. http://dx.doi.org/10.4141/cjps89-017.
Full textAbstract:
Field experiments were conducted to determine the effect of spring seedling residues of canola (Brassica napus L. and B. campestris L.), barley (Hordeum vulgare L.), flax (Linum usitatissimum L.) and a weed mixture on the growth and yield of subsequent crops of flax and barley seeded after tillage of the seedling plots. Some treatments were also tested without tillage, the seedlings being killed with paraquat. The large quantities of spring seedling residues had variable effects on flax yields, resulting in increases in some years and decreases in others compared to seedling-free plots. Flax yields were generally reduced by canola, flax and weed seedling residues, and increased by barley seedling residue. Averaged over 6 yr, canola seedlings reduced flax yields by 2% and barley increased flax yields by 3% with conventional tillage. On the other hand, barley yields were reduced 7% by conola and 17% by barley seedling residues. Yields of flax and barley were higher without than with tillage of the seedlings prior to seeding. The results are discussed in relation to the effects of the seedling residues on soil crusting, toxic compounds in the residues and toxic compounds formed during decomposition of the residues.Key words: Flax, Linum usitatissimum L., barley, Hordeum vulgare L., plant residues, tillage systems
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Moe, Roar, John E. Erwin, and Will Carlson. "Factors Affecting Gerebera jamesonii Early Seedling Branching and Mortality." HortTechnology 6, no. 1 (January 1996): 59–61. http://dx.doi.org/10.21273/horttech.6.1.59.
Full textAbstract:
The role of irradiance and/or ethylene in inducing mortality and self-branching disorders in Gerbera jamesonii Bolus. seedlings was studied. Seedling mortality increased from 8% to 57% when seed was covered with vermiculite than left uncovered during germination. Supplemental lighting for 30 days after germination decreased seedling mortality and decreased the time to visible bud compared to seed germinated under natural light only. In subsequent experiments, seeds were germinated and then seedlings were water logged or sprayed with ethephon (0.69, 3.45, or 17.25 mM) at four different stages of seedling development. Half of the ethephon-treated seedlings were sprayed with silver thiosulfate (STS). Seedling mortality was greatest after cotyledon expansion but before expansion of the first tree leaf. The highest ethephon concentration caused reduced seedling dry weight after 42 days. Applying STS did not overcome self-branching or meristem necrosis.
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Blenis, Peter V., Kathleen L. Wiggins, James E. Cunningham, and Michael A. Pickard. "Maltol protects against infection of lodgepole pine seedlings by western gall rust." Canadian Journal of Forest Research 18, no. 12 (December 1, 1988): 1658–60. http://dx.doi.org/10.1139/x88-252.
Full textAbstract:
Uptake and translocation of maltol into 6-week-old Pinusconforta (Engelm.) var. latifolia seedlings was followed by means of gas chromatography. Maltol concentrations of 6.0–7.3 mg/g seedling dry weight (46–55 μg/seedling) were observed over the first 3 days following a single application of 50 mg maltol/seedling. A split-plot design was used to determine if maltol could reduce seedling infection by Endocronartiumharknessii. Whole plots consisted of two inoculum levels (7 or 30 mg of spores per tray of seedlings) and subplots consisted of four levels of maltol (0, 2, 10, or 40 mg/mL) applied 2 days before inoculation to one-half tray of seedlings at the rate of 5 mL/cavity. The highest concentration consistently and significantly reduced seedling infection relative to the untreated control, although it also caused some phytotoxicity.
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Comeau, Philip G., Thomas F. Braumandl, and Chang-Yi Xie. "Effects of overtopping vegetation on light availability and growth of Engelmann spruce (Piceaengelmannii) seedlings." Canadian Journal of Forest Research 23, no. 10 (October 1, 1993): 2044–48. http://dx.doi.org/10.1139/x93-255.
Full textAbstract:
To examine the effects of overtopping vegetation on solar irradiance reaching Engelmann spruce (Piceaengelmannii Parry) seedlings and on crop seedling performance, neighborhood studies were established at six sites in mixed shrub–herb and fireweed communities of the Interior Cedar–Hemlock zone of southern British Columbia. These communities were dominated by mixtures of fireweed (Epilobiumangustifolium L.), thimbleberry (Rubusparviflorus Nutt.), red raspberry (Rubusidaeus L.), and (or) bracken fern (Pteridiumaquilinum (L.) Kuhn). Three hundred and eighty-eight planted Engelmann spruce seedlings, between 1 and 5 years of age, served as plot centers for measurements in 1990 and 1991. Vegetation had been clipped around 109 of these seedlings in 1988, 1989, and 1990. Seedling diameter and height were measured in the autumn of 1990 and 1991. Vegetation cover, vegetation height, and the fraction of full sunlight reaching the top branches of each spruce seedling were measured in midsummer of 1991. A simple competition index (CI), based on visually estimated percent cover, height of each species present within 1.26 m of the crop seedling, and crop-seedling height, can be used to estimate the fraction of full sunlight reaching crop seedlings. Measurements of transmittance through vegetation canopies are correlated with this competition index and could be useful as a separate, objective assessment of competition levels. Seedling growth was related to both seedling-needle biomass (at the beginning of the year) and either CI or the amount of light reaching crop seedlings during midsummer. Growth increased as needle biomass or irradiance reaching the seedling increased and decreased as CI increased. Since CI can be calculated from simple field measurements and since seedling growth is related to CI, this index has potential utility in evaluating the need for operational release treatments. Transmittance measurement provides an equally useful, and potentially more objective approach to evaluating the need for release treatment. Results from this study suggest that cumulative effects of competition result at least in part from effects on growth of seedling leaf mass.
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Sharma, G. D., R. R. Mishra, and W. R. Lyngdoh. "Influence of copper and formalin on the mycorrhiza of pine (Pinus kesiya Royle ex Gordon)." Acta Mycologica 21, no. 1 (August 20, 2014): 91–100. http://dx.doi.org/10.5586/am.1985.008.
Full textAbstract:
Various concentrations of copper sulphate and formalin were tested for their effect on the efficiency of mycorrhizal functioning in pine seedlings. Low and higher doses of copper applied to the container grown seedling exhibited a less stimulatory effect than nedium doses. When applied in higher concentrations, the formalin caused mortality in young pine seedlings. The seedling yield and phosphate uptake was found maximum in 100 ppm applied concentration of copper. while słów growth and lower phosphate concentration was observed in the seedlings not given any copper treatment. Formalin at 50 ppm concentration slightly improved the seedling growth and phosphate uptake in mycorrhizal seedling as compared with untreated ones. Variation in the development and spread of ectomycorrhiza on the surface of roots of pine seedlings was also recorded in responses to copper and formalin treatments.
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Zhao, Wen Ju, Li Rong Wang, Hong Ji, Jian Shu Song, and Yan Wei Fan. "Impacts of Plant Additive on the Seedling Bricks’ Physical Properties." Advanced Materials Research 518-523 (May 2012): 5401–5. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.5401.
Full textAbstract:
Homemade seedling bricks, which mixed and suppressed with the plant additive, clay, compost, slow-release fertilizer, can create a good living environment for plant growth, guide the development and growth of plant roots, achieve integration of bricks and seedlings to plant, and the seedlings transplant without time limit. We tested the molding density, shatter resistance, seepage rate and other physical properties of seedling bricks without plant additive, adding 5% and 10% of wheat straw, wheat shells and corn leaves, and the results show that adding plant additive can improve the physical properties of the seedling bricks effectively. The minimum density of the seedling brick contains 10% corn leaves, the minimum shatter resistance of the seedling brick contains 10% wheat straw, and the maximum seepage rate of the seedling brick contains 10% wheat straw.
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Morgan, JW. "Ecological Studies of the Endangered Rutidosis leptorrhynchoides. II. Patterns of Seedling Emergence and Survival in a Native Grassland." Australian Journal of Botany 43, no. 1 (1995): 13. http://dx.doi.org/10.1071/bt9950013.
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The emergence, survival and growth of seedlings of the endangered Rutidosis leptorrhynchoides F.Muell. were followed in a Themeda triandra grassland during 1991 and 1992. The effect of summer irrigation on seedling survival was also investigated. Seedling emergence occurred in both years within 2 weeks of the 'autumn break' when soil moisture rose above 20%. Ninety percent of emergence was observed within 4 weeks of the onset of germination and 87% of seedlings were within 20 cm of an established plant. No emergence was observed after 8 weeks. Thirteen percent of the 1991 cohort survived for 14 months. Mortality of most seedlings (63%) was attributed to soil moisture stress in summer. Small seedlings (Ͱ4 3 leaves) were no more susceptible to drought than larger seedlings. Seventy two percent of the 1991 cohort produced four leaves before subsequently dying. In 1992, however, most early seedling mortality was amongst cotyledonary seedlings. No seedlings flowered in their first year. Above-ground growth was slow and by 14 months, 60% of surviving seedlings had seven or fewer live leaves. Irrigation in a year of below-average rainfall had no significant effect on the survival and growth of seedlings. This suggests that seedling recruitment is not restricted to climatically favourable years (i.e. is not episodic) but rather, is potentially on-going provided suitable microsites are available for seedling survival.
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Kim, Hyeonji, Heejae Jo, Gwang-Jung Kim, Hyung-Sub Kim, and Yowhan Son. "Effects of Spring Warming and Drought Events on the Autumn Growth of Larix kaempferi Seedlings." Water 14, no. 12 (June 19, 2022): 1962. http://dx.doi.org/10.3390/w14121962.
Full textAbstract:
High temperatures and droughts following winter dormancy can negatively affect seedling growth and mortality. An open-field experiment was conducted to study the growth and mortality of Larix kaempferi seedlings in response to spring warming and drought treatments and to determine whether seedlings could regain their growth capability once the treatments were discontinued. In May 2020, 1-year-old seedlings were exposed to four treatments: control, warming-only, drought-only, and the combined warming and drought. Drought treatment reduced the seedling height and root collar diameter and increased the mortality rate. The combined warming and drought treatments had the highest mortality rates, followed by the drought, control, and warming treatments. However, after the cessation of the treatments, the combined warming and drought treatments increased seedling height, root collar diameter, and individual seedling biomass because the high mortality rate relaxed competition among seedlings. This suggests that the effects of low competition on the surviving seedlings may mitigate the negative effects of warming and drought on seedling growth. Our study demonstrates that despite the high mortality and decreased growth during the treatment period, seedlings subjected to combined high temperature and drought stress showed short-term high levels of growth compared to seedlings subjected to a single stress.
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Cline, E., B. Vinyard, and R. Edmonds. "Spatial effects of retention trees on mycorrhizas and biomass of Douglas-fir seedlings." Canadian Journal of Forest Research 37, no. 2 (February 2007): 430–38. http://dx.doi.org/10.1139/x06-229.
Full textAbstract:
Retention forestry places seedlings in proximity to residual trees, exposing seedlings to additional sources of ectomycorrhizal fungus (EMF) inoculum. To investigate this, Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco) seedlings were planted near (2–6 m) and far (16–30 m) from 44- to 72-year-old residual Douglas-fir trees in western Washington, USA. From 1998 through 2000, seedling shoot and root biomass was assessed and EMF taxa were identified using morphology and sequence analysis of internal transcribed spacer and large subunit ribosomal RNA genes. Seedlings near residual trees had significantly greater ectomycorrhiza (ECM) abundance (percent active ECM root tips), less necrotic root tips, and higher root to shoot biomass ratios. Seedlings near trees had a richness index of 4.1 EMF taxa per seedling and 42 total taxa compared with 3.5 taxa per seedling and 33 total taxa for seedlings far from trees. Proximity to residual trees may increase seedling ECM abundance and diversity.
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Thompson, T. E., and L. J. Grauke. "Pecan Tree Growth and Precocity." Journal of the American Society for Horticultural Science 128, no. 1 (January 2003): 63–66. http://dx.doi.org/10.21273/jashs.128.1.0063.
Full textAbstract:
Precocity of pecan [Carya illinoinensis (Wangenh.) C. Koch] seedlings (year of first fruit production) was studied in relation to original seed measurements (nut weight, buoyancy, volume, and density) and in relation to growth index (GI) measurements of seedling trees for 4 years. A total of 2,071 pecan seedlings, representing nine controlled-cross families, were studied. Original seed measurements were not related to precocity of resultant seedling trees; but seed weight, buoyancy, and volume were significantly correlated with seedling growth rates. Nut density was negatively related to growth of seedlings. These relationships show the importance of original seed measurements and seed parentage in determining seedling growth, and have direct relevance in pecan nursery operations to increase general rootstock seedling vigor. Seedling growth rate was significantly correlated to precocity levels, with measurements taken in the later years of the study showing the highest correlations with precocity. This strong growth-precocity relationship may have negative genetic implications since a common breeding objective is to produce more precocious cultivars that maintain smaller tree size in mature orchards.
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Khatun, Most Morsada, M. Ashrafuzzaman, and A. K. M. Golam Sarwar. "Performance of Purple rice cultivar under different hill density." Archives of Agriculture and Environmental Science 7, no. 3 (September 25, 2022): 355–59. http://dx.doi.org/10.26832/24566632.2022.070308.
Full textAbstract:
Purple rice has become a fascinating source of nutritional value among healthy cereal grains. A field experiment was conducted at Bangladesh Agricultural University during the Rabi season (February to May) of 2021 to evaluate the effect of number of seedlings/hill on growth, yield attributes and yield of Purple rice. Three seedling densities, viz. 1, 2 and 3 seedlings/hill, and three rice cultivars, viz. Purple rice, Pahari rice and a check BRRI dhan67 were experimental treatments and the experiment was laid out in a split-plot design with three replications. Results revealed that seedling number/hill had significant effects on the growth, yield and yield attributes of rice cultivars. The tallest plant (136.31 cm) was observed from the transplanting of 1 seedling/hill followed by 2 seedlings/hill (133.35 cm) in Pahari rice. The maximum values of the number of effective tillers (13.47; Purple rice), flag leaf length and width (41.36 and 1.24 cm; Pahari rice) were recorded from the treatment 2 seedlings/hill. The longest panicle (26.58 cm; Pahari rice) was observed in 1 seedling/hill, statistically, a similar value was found with 2 seedlings/hill (24.44 cm). Among rice cultivars, BRRI dhan67 produced the heaviest grains (1000-seed weight 23.96 g) with 2 seedlings/hill and maximum grain yield (6.35 t/ha) with 1 seedling/hill. Single seedling/hill was found to be the best management practice to get a higher yield per unit area for Purple rice and other rice cultivars also.