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Journal articles on the topic 'Cotton crops'
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1
Adhikari, Pradip, Nina Omani, Srinivasulu Ale, Paul B. DeLaune, Kelly R. Thorp, Edward M. Barnes, and Gerrit Hoogenboom. "Simulated Effects of Winter Wheat Cover Crop on Cotton Production Systems of the Texas Rolling Plains." Transactions of the ASABE 60, no. 6 (2017): 2083–96. http://dx.doi.org/10.13031/trans.12272.
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Abstract. Interest in cover crops has been increasing in the Texas Rolling Plains (TRP) region, mainly to improve soil health. However, there are concerns that cover crops could potentially reduce soil water and thereby affect the yield of subsequent cash crops. Previous field studies from this region have demonstrated mixed results, with some showing a reduction in cash crop yield due to cover crops and others indicating no significant impact of cover crops on subsequent cotton fiber yield. The objectives of this study were to (1) evaluate the CROPGRO-Cotton and CERES-Wheat modules within the cropping system model (CSM) of the Decision Support System for Agrotechnology Transfer (DSSAT) for the TRP region, and (2) use the evaluated model to assess the long-term effects of growing winter wheat as a cover crop on water balances and seed cotton yield under irrigated and dryland conditions. The two DSSAT crop modules were calibrated using measured data on soil water and crop yield from four treatments: (1) irrigated cotton without a cover crop (CwoC-I), (2) irrigated cotton with winter wheat as a cover crop (CwC-I), (3) dryland cotton without a cover crop (CwoC-D), and (4) dryland cotton with a winter wheat cover crop (CwC-D) at the Texas A&M AgriLife Research Station at Chillicothe from 2011 to 2015. The average percent error (PE) between the CSM-CROPGRO-Cotton simulated and measured seed cotton yield was -10.1% and -1.0% during the calibration and evaluation periods, respectively, and the percent root mean square error (%RMSE) was 11.9% during calibration and 27.6% during evaluation. For simulation of aboveground biomass by the CSM-CERES-Wheat model, the PE and %RMSE were 8.9% and 9.1%, respectively, during calibration and -0.9% and 21.8%, respectively, during evaluation. Results from the long-term (2001-2015) simulations indicated that there was no substantial reduction in average seed cotton yield and soil water due to growing winter wheat as a cover crop. Keywords: CERES-Wheat, Cover crop, Crop simulation model, CROPGRO-Cotton, DSSAT, Seed cotton yield, Soil water.
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SILVA FILHO, JOÃO LUÍS DA, ANA LUÍZA DIAS COELHO BORIN, and ALEXANDRE CUNHA DE BARCELLOS FERREIRA. "DRY MATTER DECOMPOSITION OF COVER CROPS IN A NO-TILLAGE COTTON SYSTEM." Revista Caatinga 31, no. 2 (June 2018): 264–70. http://dx.doi.org/10.1590/1983-21252018v31n201rc.
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ABSTRACT No-tillage cotton systems require soil coverage with cover crop residue for a longer time due to the late cycle of cotton. However, decomposition rates may vary between cover crops, and the adjustment of models to describe it is critical to no-tillage cotton management. Two non-linear regression models, exponential (EM) and Michaelis-Menten (MM), were adjusted to dry matter decomposition of cover crops in a cotton no-tillage system, in Brazil. Three field trials were performed in 2012 for the cover crops Urochloa ruziziensis (brachiaria), Pennisetum glaucum (pearl millet), and Cajanus cajan (pigeon pea). Samples of cover crop were collected at 20, 50, 70, 110, 140, and 170 days after sowing upland cotton to measure dry matter decomposition. MM showed better adjustment than EM for all cover crops. The estimations of half-life parameters were different between the cover crops, suggesting that each cover crop has its own rate of decomposition. For pearl millet, brachiaria, and pigeon pea, the half-life estimation by exponential model was over the MM in 9, 12, and 12 days.
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Tillman, P. G., and T. E. Cottrell. "Case Study: Trap Crop with Pheromone Traps for SuppressingEuschistus servus(Heteroptera: Pentatomidae) in Cotton." Psyche: A Journal of Entomology 2012 (2012): 1–10. http://dx.doi.org/10.1155/2012/401703.
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The brown stink bug,Euschistus servus(Say), can disperse from source habitats, including corn,Zea maysL., and peanut,Arachis hypogaeaL., into cotton,Gossypium hirsutumL. Therefore, a 2-year on-farm experiment was conducted to determine the effectiveness of a sorghum (Sorghum bicolor(L.) Moench spp.bicolor) trap crop, with or withoutEuschistusspp. pheromone traps, to suppress dispersal of this pest to cotton. In 2004, density ofE. servuswas lower in cotton fields with sorghum trap crops (with or without pheromone traps) compared to control cotton fields. Similarly, in 2006, density ofE. servuswas lower in cotton fields with sorghum trap crops and pheromone traps compared to control cotton fields. Thus, the combination of the sorghum trap crop and pheromone traps effectively suppressed dispersal ofE. servusinto cotton. Inclusion of pheromone traps with trap crops potentially offers additional benefits, including: (1) reducing the density ofE. servusadults in a trap crop, especially females, to possibly decrease the local population over time and reduce the overwintering population, (2) reducing dispersal ofE. servusadults from the trap crop into cotton, and (3) potentially attracting more dispersingE. servusadults into a trap crop during a period of time when preferred food is not prevalent in the landscape.
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Tingle, C. H., and J. M. Chandler. "The Effect of Herbicides and Crop Rotation on Weed Control in Glyphosate-Resistant Crops." Weed Technology 18, no. 4 (December 2004): 940–46. http://dx.doi.org/10.1614/wt-02-126.
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Field studies were conducted from 1998 through 2000 to determine the influence of crop rotation and level of herbicide system for johnsongrass, entireleaf morningglory, and smellmelon control in glyphosate-resistant cotton and corn. Three different crop rotation schedules were used including cotton–cotton–cotton, cotton–corn–cotton, and corn–cotton–corn. Herbicide systems involving various degrees of input levels (low, medium, and high) were compared with a conventional standard program. In 1998, weed control ranged from 80 to 95% for all herbicide systems when the rotation was corn–cotton–corn. In 1999 and 2000, the low-input herbicide system controlled entireleaf morningglory 76 to 78% late in the season. Decreased smellmelon control (78%) was also observed with the conventional standard during this same period. In the cotton–corn–cotton rotation, late-season entireleaf morningglory control decreased each year in the low-input system, regardless of crop. In 2000, late-season evaluations indicated lower weed control of all three species with the conventional standard program compared with the other input systems. Yield data from 2000 suggested that corn and seed cotton yields were influenced by crop rotation.
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Verma, D., M. H. Kalubarme, G. P. Saroha, K. S. Mohan, K. C. Ravi, and A. N. Singh. "MONITORING CHANGES IN COTTON ACREAGE AND ALTERNATE HOST CROPS OF COTTON BOLLWORM USING REMOTE SENSING AND GIS IN MAJOR COTTON GROWING REGIONS OF INDIA." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-3/W6 (July 26, 2019): 525–33. http://dx.doi.org/10.5194/isprs-archives-xlii-3-w6-525-2019.
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<p><strong>Abstract.</strong> Cotton cultivation has made rapid strides in India since the introduction of Bt cotton, which provided effective protection against its major pest, <i>Helicoverpa armigera</i> and other bollworms. The presence of alternate host crops for cotton bollworms targeted by Bt cotton play a key role in resistance evolution to the <i>in planta</i> expressed Bt proteins. Several host crops for <i>H. armigera</i> such as pigeonpea, sorghum, tomato, chilli, sunflower and corn are cultivated alongside Bt cotton. Change detection in the extent of cotton and alternate host crops of cotton bollworm was conducted using IRS LISS-III data in Punjab, Haryana, Rajasthan, Gujarat, Maharashtra, Andhra Pradesh and Karnataka states. The changes in the extent of cotton and host crops were monitored using multi-temporal data of 2002, 2004 and 2008. The results indicated that Bt cotton (Hirsutum) has almost completely replaced the traditional Indian cotton (<i>Gossypium arborium</i>). Several alternate host crops of H. armigera were grown along with cotton. Pigeonpea was the major host crop in almost all the locations. Chilies dominated in Andhra Pradesh, sunflower in Karnataka and corn in Gujarat. These host crops serve as ‘natural’ refuge of <i>H. armigera</i> and possibly, for this reason this pest has not evolved resistance to the Bt expressed by Bollgard II even after 16 seasons of intensive cultivation; whereas the pink bollworm, a monophagous cotton bollworm, had developed resistance to Cry1Ac in 2009 and to Cry1Ac and Cry2Ab in 2015.</p>
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Vishwanath Gowdru, Nithya. "A Resources use efficiency analysis of Bt and Non Bt cotton farmers in Karnataka, India." Journal of Global Economy 9, no. 3 (October 3, 2013): 175–81. http://dx.doi.org/10.1956/jge.v9i3.283.
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Cotton is the major commercial crop amongst all cash crops in India and provides livelihood to more than 60 million people in its cultivation, processing and textile industry. Cotton crop is infested by various pests causing significant yield losses therefore Bt cotton was introduced in India to reduce pesticide consumption and also increase productivity. Since introduction there has been ongoing debate on the superiority and/ or inferiority of Bt cotton over non Bt cotton. Therefore the present study was undertaken to examine the Bt cotton technology on output and efficiency of inputs used in cotton cultivation in Karnataka state of South India during 2007. Primary data was collected from 90 farmers cultivating Bt and non-Bt cotton in Haveri district, Karnataka, India. The Cobb-Douglas production and decomposition analysis techniques were used to estimate the influence of factors and Bt technology on output change. The production function analysis indicated that the co-efficients of expenditure on fertilizers, labour, plant protection chemicals and land were significant in case of Bt cotton cultivation. The result of Resource use efficiency analysis showed that efficient use of labour, fertilizers and seeds had contributed the most to the difference in returns between Bt-cotton and non-Bt cotton cultivation. Contribution of differences in the quantity of inputs used to higher returns from Bt cotton to the measured difference in gross returns between Bt and non-Bt cotton was 56.56 per cent, while that of the efficiency in the use of inputs was 23.83 per cent. Key words: Bt cotton, Resource use efficiency, Decomposition analysis
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Palhano, Matheus G., Jason K. Norsworthy, and Tom Barber. "Cover Crops Suppression of Palmer Amaranth (Amaranthus palmeri) in Cotton." Weed Technology 32, no. 1 (November 17, 2017): 60–65. http://dx.doi.org/10.1017/wet.2017.97.
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AbstractWith the recent confirmation of protoporphyrinogen oxidase (PPO)-resistant Palmer amaranth in the US South, concern is increasing about the sustainability of weed management in cotton production systems. Cover crops can help to alleviate this problem, as they can suppress weed emergence via allelochemicals and/or a physical residue barrier. Field experiments were conducted in 2014 and 2015 at the Arkansas Agricultural Research and Extension Center to evaluate various cover crops for suppressing weed emergence and protecting cotton yield. In both years, cereal rye and wheat had the highest biomass production, whereas the amount of biomass present in spring did not differ among the remaining cover crops. All cover crops initially diminished Palmer amaranth emergence. However, cereal rye provided the greatest suppression, with 83% less emergence than in no cover crop plots. Physical suppression of Palmer amaranth and other weeds with cereal residues is probably the greatest contributor to reducing weed emergence. Seed cotton yield in the legume and rapeseed cover crop plots were similar when compared with the no cover crop treatment. The seed cotton yield collected from cereal cover crop plots was lower than from other treatments due to decreased cotton stand.
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Duzy, Leah M., and Ted S. Kornecki. "Effects of cover crop termination and cotton planting methods on cotton production in conservation systems." Renewable Agriculture and Food Systems 34, no. 5 (December 14, 2017): 406–14. http://dx.doi.org/10.1017/s1742170517000631.
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AbstractIn conservation agriculture, cover crops are utilized to improve soil properties and to enhance cash crop growth. One important part of cover crop management is termination. With smaller profit margins and constraints on time and labor, producers are searching for ways to reduce time and labor required to terminate cover crops while maintaining or increasing profitability. This study examined the effect of 11 different combinations of terminating cereal rye (Secale cerealeL.) and planting cotton (Gossypium hirsutumL.) on population, seed cotton yield, total costs and net returns; and how combined operations affect labor, fuel consumption and carbon (CO2) emissions in a conservation system. Cereal rye followed by cotton was planted in central Alabama during the 2009–2011 crop years. Treatments included cotton planted directly into standing cereal rye, cover crops terminated at early milk growth stage using mechanical (roller or roller/crimper) with or without chemical termination (spraying) followed by cotton planting, and cover crop termination combined with cotton planting using spraying with or without rolling termination. While the 2011 crop year had the lowest plant populations, there was no year effect on seed cotton yields, total costs or net returns. Rolling with or without spraying yielded higher plant populations (26%), seed cotton yields (18.3%) and net returns (17.2%) than cotton planted into standing rye; however, rolling with or without spraying also had 23.8% higher costs due to increased fuel usage, machinery and labor hours, and yield varying costs. While rolling with spraying had slightly higher total costs compared with rolling alone (6.5%), plant populations, seed cotton yields and net returns were 11.42%, 6.4% and 6.5% higher, respectively. Converting from three separate operations for cover crop termination and cotton planting to rolling and spraying combined with planting, producers could potentially reduce CO2emissions from fuel use and labor hours associated with cover crop termination and cotton planting by up to 51%.
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Cooper, J. L. "A grower survey of rotations used in the New South Wales cotton industry." Australian Journal of Experimental Agriculture 39, no. 6 (1999): 743. http://dx.doi.org/10.1071/ea98055.
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Summary. Cotton growers in the Macquarie, Namoi and Gwydir Valleys of New South Wales were surveyed in 1992 to determine what crops are grown in rotation with cotton, how frequently rotation crops are used, and what influences the grower’s choice of rotation system. A total of 155 properties were surveyed, covering 100, 49 and 58% of irrigated cotton produced in the Macquarie, Namoi and Gwydir Valleys, respectively. Although a large part of the 1992–93 cotton crop (61% by area) did not follow a rotation crop, there was widespread interest in rotations and 70% of properties had used rotations. Wheat was by far the most widely grown rotation crop, but there was considerable interest in other crops, especially legumes. The perceived benefits from rotation crops reported by most growers were better soil structure, less disease in following cotton, and more soil organic matter. However, when asked why they preferred certain rotation crops, these factors did not rate highly with growers. Crops that were easy to grow and gave the best financial returns possessed the main features sought in a rotation crop. The greatest problem in growing rotation crops was a lack of irrigation water. It is not surprising that this problem ranked highly because when the survey was conducted, the Namoi and Gwydir Valleys had water allocations of 15 and 0%, respectively. Not having suitable equipment to sow rotation crops was also a problem for 17% of growers, but 10% encountered no problems. The survey also investigated the use of permanent beds and retained hills. These practices have benefits for soil structure, and are almost essential for rotation crops which need to be sown as soon as the cotton is harvested. Over 80% of growers using rotations had adopted some form of permanent beds or retained hills. The benefit which ranked highest was a reduction in costs, followed by less soil compaction. Some growers (44%) who used permanent beds or retained hills had no problems, but handling the trash and keeping the rows straight were of concern to others.
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Zablotowicz, Robert M., Krishna N. Reddy, L. Jason Krutz, R. Earl Gordon, Ryan E. Jackson, and Leslie D. Price. "Can Leguminous Cover Crops Partially Replace Nitrogen Fertilization in Mississippi Delta Cotton Production?" International Journal of Agronomy 2011 (2011): 1–9. http://dx.doi.org/10.1155/2011/135097.
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Petroleum prices impact cotton nitrogen (N) fertilization cost. A field study was conducted from 2005 to 2007 to assess the interactions of cover crop (none, Austrian winter pea (Pisum sativumspp.arvense) or hairy vetch (Vicia villosaRoth)) and N fertilization (0, 67 or 134 kg N/ha applied at planting) on N availability and cotton yield under reduced-tillage management. Nitrogen content in desiccated residues averaged 49, 220, and 183 kg N/ha, in no cover crop, Austrian winter pea, and hairy vetch, respectively. Seventy percent of N in the above ground cover crop was derived from biological N fixation. In 2005, cover crops decreased cotton yield, while fertilizer N had no effect. In 2006, cover crops did not affect yield, but yield was positively correlated with N rate. In 2007, in no N plots, cotton yields were 65% higher in cover crops than in no cover crop. However, yield from N fertilized cover crop plots were similar to N fertilized no cover plots. These results indicate that leguminous cover crops can provide over 150 kg N/ha, but this N may not be as effective as fertilizer N for lack of synchronization between cotton N requirements and N release from residues.
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Tillman, P. Glynn. "Tobacco as a Trap Crop for Heliothis virescens (F.) (Lepidoptera: Noctuidae) in Cotton." Journal of Entomological Science 41, no. 4 (October 1, 2006): 305–20. http://dx.doi.org/10.18474/0749-8004-41.4.305.
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A 3-yr study evaluated tobacco as a trap crop for the tobacco budworm, Heliothis virescens (F.), in cotton. Small plot experiments were conducted on an experimental farm at Mississippi State University in Starkville, MS, in 1996 and on a commercial farm in Aliceville, AL, in 1997 to determine the ability of small strips of tobacco to trap H. virescens in cotton field plots. In the 1996 experiment, tobacco budworms eggs were significantly higher on tobacco than on cotton from 7 June through 19 June and from 10 July through 22 July. In 1997, H. virescens eggs were significantly higher on tobacco than on cotton for every sampling date throughout the growing season. The conclusion derived from these small plot experiments was that H. virescens females preferred tobacco over cotton as an ovipositional site. Therefore, in 1998, a large-scale field experiment was conducted to determine the effectiveness of tobacco as a trap crop for H. virescens in commercial cotton fields in Funston, GA. In this experiment, the number of H. virescens eggs was significantly lower in cotton fields with tobacco trap crops compared to control cotton fields without tobacco trap crops on 2 and 9 July. Also, economic threshold for H. virescens was not reached in these cotton fields with tobacco trap crops. In contrast, the economic threshold for this pest was met in cotton fields without tobacco trap crops on two dates during the growing season. For each year of the study, percentage total real mortality (rx) for eggs and larvae of H. virescens on tobacco was very high, ranging from 91.4–99.9%. Larval mortality was attributed in part to parasitization by Toxoneuron nigriceps (formerly Cardiochiles nigriceps) Viereck and Campoletis sonorensis Cameron and an infection by an ascovirus of H. virescens. Thus, tobacco served as a trap crop and sink for H. virescens in cotton in this study.
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Shekoofa, Avat, Sara Safikhan, Tyson B. Raper, and Shawn A. Butler. "Allelopathic Impacts of Cover Crop Species and Termination Timing on Cotton Germination and Seedling Growth." Agronomy 10, no. 5 (May 1, 2020): 638. http://dx.doi.org/10.3390/agronomy10050638.
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The integration of cover crops into cotton (Gossypium hirsutum, L.) production remains challenging. One potential negative impact of cover crops on cotton is allelopathy. Proper selection of cover crop species and termination timing could potentially reduce the impacts of allelopathy on cotton seedlings. Two studies were conducted to determine cotton germination and growth sensitivity to cover crop leachate, which were measured using (I) five cover crops species, including: oats (Avena sativa L.), hairy vetch (Vicia Villosa), winter pea (Lathyrus hirsutus), winter wheat (Triticum aestivum), and annual rye (Lolium multiflorum), and (II) a blend of cover crops at four termination timings, including: at planting, three weeks prior to planting, six weeks prior to planting, and a split termination, where a 25 cm band in the top of the bed was terminated six weeks prior to planting, and the remaining cover crop was terminated at planting (referred to as strip 6-wk). Samples for Experiment I were collected on May 24th and for Experiment II on March 22nd (Strip/6-wk and 6-wk), April 30th (3-wk), and May 11th (at planting) in 2018. The effect of 0 (deionized water), 25, and 50 (v/v) cover crop leachate extract on cotton seed germination was evaluated in a series of controlled environmental studies. All cover crop species’ leachates negatively impacted cotton germination and seedling growth (p < 0.05). Germination inhibition rates declined numerically by species, with winter pea ≥ hairy vetch ≥ oats ≥ annual rye ≥ winter wheat at the 50 v/v concentrations. Winter pea germination inhibition on cotton equaled 47.0% and cotton radicle length was decreased by 62.8%. Termination at planting suppressed cotton germination more than the other termination timings, with the 50 v/v treatment resulting in a germination inhibition of 60.0%. Proper selection of cover crop species and termination timing prior to planting cotton will be critical in maximizing the benefits and minimizing the risks of a cover crop.
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Wang, Li, and Hui Mao. "Reformation Ideas and Suggestions to the Cotton Standardized Production Management Model in Xinjiang Corps." Applied Mechanics and Materials 651-653 (September 2014): 1615–18. http://dx.doi.org/10.4028/www.scientific.net/amm.651-653.1615.
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The demestic and foreign agricultural development experience shows that cotton standardization as an important sign of cotton modernization is very important to advance cotton industrialization,ensure the quality of cotton. The product standardization of cotton is the key point to develop cotton and increase farmer income. According to a field survey studied by Xinjiang Corps, by analyzing the current situation of Crops cotton, the new direction of Crops cotton production and operation medol is to reduce the labor input,reduce the cost of cotton production,improve cotton production scale and atandardization,and protect and enhance the interests of the main production,at last policy suggestions are established on promoting Crops cotton standardization.
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Miller, Gilbert, and Jeremy Greene. "Intercropping Seedless Watermelon and Cotton." HortScience 53, no. 12 (December 2018): 1799–803. http://dx.doi.org/10.21273/hortsci13428-18.
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Intercropping of seedless watermelon [Citrullus lanatus (Thumb.) Matsum. & Nak.] and cotton [Gossypium hirsutum (L.)] in the eastern geographical area of South Carolina requires changes in normal crop-management programs but has the potential to improve grower profits compared with typical production of each crop separately. The alteration and timing of several normal crop-production practices for both crops can present challenges and must be well-defined for successful intercropping of watermelon and cotton in the region. Notable adjustments in production for watermelon are delayed planting date, reduced row spacing and bed width, and modification of herbicide applications. Significant changes in normal cotton production also include modification of herbicide applications, but additional considerations, such as temporal limits on side-dressed fertilizer and insecticide applications, are needed because of the raised beds and plasticulture used for watermelons and also because of labeling restrictions for pesticides across crops. Research was conducted to 1) identify modifications in standard crop-management procedures for watermelon and cotton intercropping; and 2) determine the feasibility and profitability of intercropping the crops. Although there was a slight numerical reduction in intercropped watermelon yield each year, there were no significant differences in total watermelon yield between intercropping and watermelon monoculture in any of the years. There were also no significant differences in watermelon fruit quality parameters (size, brix, hard seed, hollow heart) in any of the years. Intercropped cotton yield was significantly less than monoculture cotton yields in each of the three years. The net income from intercropping in each year was slightly less than the net income from watermelon monoculture.
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Baker, Geoff H., Colin R. Tann, and Gary P. Fitt. "Production of Helicoverpa spp. (Lepidoptera, Noctuidae) from different refuge crops to accompany transgenic cotton plantings in eastern Australia." Australian Journal of Agricultural Research 59, no. 8 (2008): 723. http://dx.doi.org/10.1071/ar07421.
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The adoption of transgenic (Bt) cotton varieties has markedly reduced feeding damage by noctuid pests, Helicoverpa armigera and H. punctigera, in Australian cotton crops. However, the potential for Bt resistance to evolve within these insect pests is a major concern. To reduce the likelihood of Bt resistance occurring, it is mandatory for growers of Bt cotton to also grow refuge crops which produce large numbers of Bt-susceptible moths. We present here findings from a series of field studies which sought to identify the relative Helicoverpa productivity of different refuge crop options. The abundance of Helicoverpa pupae (during the cotton season) was compared under crops of Ingard® (transgenic, single Bt gene) cotton, sprayed conventional cotton, and various unsprayed refuge crops (cotton, sorghum, maize, pigeon pea) from 1996 to 2003 in the major cotton-producing regions of northern New South Wales, plus St George and Dirranbandi in southern Queensland. Unsprayed, conventional cotton was used as the ‘control’ refuge in these studies. Productivity of adult Helicoverpa was estimated by surveying for pupae and discounting those that were parasitised and dead. Some supplementary experiments were also conducted to evaluate specific issues, in particular the value of additional refuge crops sown late in 2000–01 (due to accidental over-planting of Ingard® cotton that year) and the potential productivity of mixed plantings of various refuge crops which individually flowered at different times throughout the cotton season. Unsprayed refuges generally produced many more pupae than sprayed, conventional cotton and Ingard® cotton. Overall, pigeon pea, which has the advantage of prolonged flowering and thus on-going attractiveness to Helicoverpa, was the most reliable and productive refuge option, producing about twice as many pupae as unsprayed cotton. The seed mix refuge is perhaps a viable alternative option, although logistically more difficult for growers to adopt. Laboratory rearing of live pupae until moth emergence indicated that parasitism can be a substantial source of mortality in some refuge crops, especially sorghum. The most common parasitoid of Helicoverpa pupae was the ichneumonid wasp, Heteropelma scaposum. Such parasitism can greatly reduce productivity of adult Helicoverpa from refuges and needs to be taken into account when assessing relative refuge ‘value’, although such refuges will obviously contribute to the abundance of these beneficial species across the landscape.
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Rochester, Ian J. "Phosphorus and potassium nutrition of cotton: interaction with sodium." Crop and Pasture Science 61, no. 10 (2010): 825. http://dx.doi.org/10.1071/cp10043.
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Poor phosphorus (P) and potassium (K) nutrition limits the growth and yield of many cotton (Gossypium hirsutum L.) crops in Australia. The demand for nutrients from cotton crops has risen as yields have increased over the past 40 years, and some soils have become depleted in these nutrients. Cotton is commonly grown on sodic soils that are more prone to nutritional problems. A survey of thirty-one sites over four years in northern NSW, Australia included twelve sites that had sodic topsoil. However, available soil P and K at all sites were above established critical values for cotton crops. Soil sodicity was negatively correlated with available soil P and K, and positively with soil salinity and chloride. Cotton leaf P and K concentrations at flowering were negatively correlated with leaf sodium (Na) concentration. The cotton crops growing in sodic soils produced 20% less dry matter (3 weeks before crop defoliation) and crop P and K uptake was reduced by 23% and 25%, respectively, whereas Na uptake was 107% higher. High soil sodicity also reduced the uptake of micro-nutrients. Two field experiments in adjacent sodic and non-sodic areas on one farm showed a yield response to P fertiliser application at the non-sodic site only, but where soil P availability was above the accepted critical value. Application of K fertiliser did not increase crop K uptake or yield. The lower yield and poorer growth of irrigated cotton on sodic soils was related to higher Na uptake and lower P and K uptake, possibly due to restricted root growth in sodic soils.
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Norsworthy, Jason K., Marilyn McClelland, Griff Griffith, Sanjeev K. Bangarwa, and Joshua Still. "Evaluation of Legume Cover Crops and Weed Control Programs in Conservation-Tillage, Enhanced Glyphosate-Resistant Cotton." Weed Technology 24, no. 3 (September 2010): 269–74. http://dx.doi.org/10.1614/wt-d-09-00037.1.
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Research was conducted at Marianna, AR, for 2 yr to determine whether hairy vetch and Austrian winter pea cover crops would aid weed management programs in conservation-tilled, enhanced glyphosate-resistant cotton. Both cover crops were easily established and produced rapid growth in early spring, with biomass production of 435 to 491 g m−2by Austrian winter pea and 415 to 438 g m−2by hairy vetch. The effect of cover crops on weed control was short-lived in both years, with herbicide programs being the major determinant of weed control and seed-cotton yield. Averaged over cover crops, seed-cotton yields when the initial in-crop glyphosate application was delayed to the four-node cotton stage were up to 710 kg ha−1less than in a PRE herbicide program. In 1 of 2 yr, seed-cotton yields were greater in PRE-treated plots compared with a program where initial weed management was delayed to the one-leaf stage of cotton. As a result of rapid decay of hairy vetch and Austrian winter pea biomass following cotton planting and the lack of adequate Palmer amaranth, pitted morningglory, and goosegrass control in the absence of herbicides, it appears there may be minimal weed management benefits from the use of hairy vetch and Austrian winter pea in Midsouth cotton production.
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Tillman, P. G., T. E. Cottrell, R. F. Mizell, and E. Kramer. "Effect of field edges on dispersal and distribution of colonizing stink bugs across farmscapes of the Southeast USA." Bulletin of Entomological Research 104, no. 1 (September 18, 2013): 56–64. http://dx.doi.org/10.1017/s0007485313000497.
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AbstractStink bugs (Heteroptera: Pentatomidae), including Nezara viridula (L.), Euschistus servus (Say), and Chinavia hilaris (Say), are economic pests in farmscapes where they move within and between closely associated crop and non-crop habitats. Thus, field edges in these farmscapes include not only crop-to-crop interfaces but also those edges adjoining non-crop habitats. We examined the influence of field edges on colonization of stink bugs in southeastern USA farmscapes composed of typical combinations of corn, peanut, and cotton. For E. servus and N. viridula, egg-to-adult development and presence of both sexes on all crops indicated that the crops served as reproductive plants. Adult C. hilaris were rarely found on corn and on crops associated with it, and they were present mainly in cotton in peanut–cotton farmscapes. Mature crop height was significantly higher for corn than for cotton and significantly higher for cotton over peanut, and an edge effect in dispersal of stink bugs into a crop was detected up to 4.6, 8.2, and 14.6 m from the crop-to-crop interface in corn, cotton, and peanut, respectively. These results suggest that stink bug dispersal into a crop decreases as crop height increases. The first stink bug-infested crop at the crop-to-crop interface was the most significant contributor of colonizing stink bugs to an adjacent crop. An edge effect in dispersal of stink bug adults was detected in corn next to non-woodlands and woodlands and in cotton adjacent to woodlands. Edge effects were never detected in side edges of peanut. Overall, our results indicate that both plant height and host plant suitability can influence edge-mediated dispersal of stink bugs at field edges.
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Davis, R. M., and J. J. Nunez. "Influence of Crop Rotation on the Incidence of Pythium- and Rhizoctonia-Induced Carrot Root Dieback." Plant Disease 83, no. 2 (February 1999): 146–48. http://dx.doi.org/10.1094/pdis.1999.83.2.146.
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The influence of various crop rotations on population densities of Pythium spp. and Rhizoctonia solani, subsequent carrot yields, and incidence of carrot root dieback was investigated. Carrots followed crops of alfalfa, barley, carrots, cotton, onions, or fallowed soil in two independent trials. Populations of Pythium spp. were greater following alfalfa and barley than other crops in one of the 2 years of the study. Populations of R. solani were generally greater following alfalfa and cotton than other crops in each of the 2 years of the study. In 1 year, yields of marketable carrots were reduced following the alfalfa crop; no other cropping pattern influenced carrot yields. The incidence of root dieback, which resulted in mature carrots with misshapen or multiple taproots, was generally greater following alfalfa and barley than other crops in one trial, and greater following alfalfa and cotton in the other trial.
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Leonteva, I. "Survey of Cotton-plant Agrocenosis Insects in the Eastern Part of the Republic of Turkmenistan." Bulletin of Science and Practice 6, no. 1 (January 15, 2020): 21–27. http://dx.doi.org/10.33619/2414-2948/50/03.
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To date, the high importance of cultivation industrial crops is universally recognized. One of these crops — cotton–plant (Gossypium hirsutum) — is the most important crop grown in Central Asia. The study of the species diversity of insects in crops of agricultural plants, including cotton–plant, is of great practical and theoretical interest, which allows us to assess the phytosanitary condition of crops and to develop a set of measures to improve them. The greatest economic damage to cotton–plant crops is caused by insects, among which are multivivorous (turnip moth, cotton bollworm, aphid, etc.) and specialized (more than 20 species). They damage almost all the organs of a given plant: roots, stems, leaves, generative organs (flowers and fruits) during their formation and maturation. In order to study the species diversity of insects in the cotton–plant agrocenosis under the conditions of the Lebap velayat of the Republic of Turkmenistan in 2019, more than 1000 insect specimens were collected. 12 species belonging to 7 orders and 10 families were identified. In the process of scientific research, predominantly polyphagous pests were recorded, which include two species of grasshoppers, two species of owlet moths, aphids, etc. In addition to pests of this culture, two species of predatory insects were found (European mantis and Bronze Carabid).
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SALAM, ABDUL, and SADIA TUFAIL. "Economic Efficiency and Distortions to Incentives in Production of Cotton and Rice Crops in Punjab." NUST Journal of Social Sciences and Humanities 2, no. 1 (January 20, 2021): 29–49. http://dx.doi.org/10.51732/njssh.v2i1.9.
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The study based on crop budgets, for 2010-12 crops, was, inter alia, designed to examine economic efficiency and distortions in incentives to production of cotton and basmati rice, long grain aromatic rice, crops in Punjab. The analysis has confirmed the competitiveness of their production in Punjab as farmers’ gross revenues from these crops exceeded their total costs, enabling farmers make some profit. The competitiveness, nevertheless, is sensitive to changes in prices of the produce and those of the inputs. The analysis conducted at economic prices have indicated economic efficiency and comparative advantage of Punjab in producing both basmati rice and cotton. The domestic resource cost coefficients for basmati as well as cotton were consistently less than one, confirming Punjab’s comparative advantage and economic efficiency in their farming. The estimation and analysis of nominal projection coefficients and effective protection coefficients for basmati and cotton crops have indicated implicit taxation as well as some protection to domestic producers. The results of economic efficiency and comparative advantage, of both basmati and cotton, are quite sensitive to the fluctuations and developments in world markets with spill over to the domestic market, impacting their competitiveness.
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Aslanov, Q., and N. Quliyeva. "Effect of the Crops Density and Inorganic Fertilizers on the Cotton Crop Yield in Summer Planting." Bulletin of Science and Practice 7, no. 3 (March 15, 2021): 58–63. http://dx.doi.org/10.33619/2414-2948/64/06.
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The article discusses the issues of scientific solution of the State Program for the development of cotton growing in the Republic of Azerbaijan. Ganja-Gazakh zone has been irrigated for a long time and is widely used both in the cultivation of cotton and grain, melons and vegetables. The results of the influence of organic and mineral fertilizers on the plant density of cotton after barley harvest are analyzed. The optimal doses of fertilizers for obtaining a high, high-quality and sustainable yield of raw cotton have been determined.
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Hulugalle, N. R., and F. Scott. "A review of the changes in soil quality and profitability accomplished by sowing rotation crops after cotton in Australian Vertosols from 1970 to 2006." Soil Research 46, no. 2 (2008): 173. http://dx.doi.org/10.1071/sr07077.
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In agricultural systems, soil quality is thought of in terms of productive land that can maintain or increase farm profitability, as well as conserving soil resources so that future farming generations can make a living. Management practices which can modify soil quality include tillage systems and crop rotations. A major proportion of Australian cotton (Gossypium hirsutum L.) is grown on Vertosols (~75%), of which almost 80% is irrigated. These soils have high clay contents (40–80 g/100 g) and strong shrink–swell capacities, but are frequently sodic at depth and prone to deterioration in soil physical quality if incorrectly managed. Due to extensive yield losses caused by widespread deterioration of soil structure and declining fertility associated with tillage, trafficking, and picking under wet conditions during the middle and late 1970s, a major research program was initiated with the objective of developing soil management systems which could improve cotton yields while concurrently ameliorating and maintaining soil structure and fertility. An outcome of this research was the identification of cotton–winter crop sequences sown in a 1 : 1 rotation as being able to sustain lint yields while at the same time maintaining soil physical quality and minimising fertility decline. Consequently, today, a large proportion (~75%) of Australian cotton is grown in rotation with winter cereals such as wheat (Triticum aestivum L.), or legumes such as faba bean (Vicia faba L.). A second phase of research on cotton rotations in Vertosols was initiated during the early 1990s with the main objective of identifying sustainable cotton–rotation crop sequences; viz. crop sequences which maintained and improved soil quality, minimised disease incidence, facilitated soil organic carbon sequestration, and maximised economic returns and cotton water use efficiency in the major commercial cotton-growing regions of Australia. The objective of this review was to summarise the key findings of both these phases of Australian research with respect to soil quality and profitability, and identify future areas of for research. Wheat rotation crops under irrigated and dryland conditions and in a range of climates where cotton is grown can improve soil quality indicators such as subsoil structure, salinity, and sodicity under irrigated and dryland conditions, while leguminous crops can increase available nitrogen by fixing atmospheric nitrogen, and by reducing N volatilisation and leaching losses. Soil organic carbon in most locations has decreased with time, although the rate of decrease may be reduced by sowing crop sequences that return about 2 kg/m2.crop cycle of residues to the soil, minimising tillage and optimising N inputs. Although the beneficial effects of soil biodiversity on quality of soil are claimed to be many, except for a few studies on soil macrofauna such as ants, conclusive field-based evidence to demonstrate this has not been forthcoming with respect to cotton rotations. In general, lowest average lint yields per hectare were with cotton monoculture. The cotton–wheat systems generally returned higher average gross margins/ML irrigation water than cotton monoculture and other rotation crops. This indicates that where irrigation water, rather than land, is the limiting resource, cotton–wheat systems would be more profitable. Recently, the addition of vetch (Vicia villosa Roth.) to the cotton–wheat system has further improved average cotton yields and profitability. Profitability of cotton–wheat sequences varies with the relative price of cotton to wheat. In comparison with cotton monoculture, cotton–rotation crop sequences may be more resilient to price increases in fuel and fertiliser due to lower overall input costs. The profitability of cotton–rotation crop sequences such as cotton–wheat, where cotton is not sown in the same field every year, is more resilient to fluctuations in the price of cotton lint, fuel and nitrogen fertiliser. This review identified several issues with respect to cotton–rotation crop sequences where knowledge is lacking or very limited. These are: research into ‘new’ crop rotations; comparative soil quality effects of managing rotation crop stubble; machinery attachments for managing rotation crop stubble in situ in permanent bed systems; the minimum amount of crop stubble which needs to be returned per cropping cycle to increase SOC levels from present values; the relative efficacy of C3 and C4 rotation crops in relation to carbon sequestration; the interactions between soil biodiversity and soil physical and chemical quality indicators, and cotton yields; and the effects of sowing rotation crops after cotton on farm and cotton industry economic indicators such as the economic incentives for adopting new cotton rotations, farm level impacts of research and extension investments, and industry- and community/catchment-wide economic modelling of the impact of cotton research and extension activities.
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Jhala, Amit J., Hugh J. Beckie, Thomas J. Peters, A. Stanley Culpepper, and Jason K. Norsworthy. "Interference and management of herbicide-resistant crop volunteers." Weed Science 69, no. 3 (January 22, 2021): 257–73. http://dx.doi.org/10.1017/wsc.2021.3.
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AbstractSince the commercialization of herbicide-resistant (HR) crops, primarily glyphosate-resistant crops, their adoption has increased rapidly. Multiple herbicide resistance traits in crops such as canola (Brassica napus L.), corn (Zea mays L.), cotton (Gossypium hirsutum L.), and soybean [Glycine max (L.) Merr.] have become available in recent years, and management of their volunteers needs attention to prevent interference and yield loss in rotational crops. The objectives of this review were to summarize HR crop traits in barley (Hordeum vulgare L.), canola, corn, cotton, rice (Oryza sativa L.), soybean, sugarbeet (Beta vulgaris L.), and wheat (Triticum aestivum L.); assess their potential for volunteerism; and review existing literature on the interference of HR crop volunteers, yield loss, and their management in rotational crops. HR crop volunteers are problem weeds in agronomic cropping systems, and the impact of volunteerism depends on several factors, such as crop grown in rotation, the density of volunteers, management practices, and microclimate. Interference of imidazolinone-resistant (IR) barley or wheat volunteers can be a problem in rotational crops, particularly when IR crops such as canola or wheat are grown. HR canola volunteers are abundant in the Northern Great Plains due to high fecundity, seed loss before or during harvest, and secondary seed dormancy, and they can interfere in crops grown in rotation such as flax (Linum usitatissimum L.), field peas (Pisum sativum L.), and soybean. HR corn volunteers are competitive in crops grown in rotation such as corn, cotton, soybean, and sugarbeet, with yield loss depending on the density of HR corn volunteers. Volunteers of HR cotton, rice, soybean, and sugarbeet are not major concerns and can be controlled with existing herbicides. Herbicide options would be limited if the crop volunteers are multiple HR; therefore, recording the cultivar planted the previous year and selecting the appropriate herbicide are important. The increasing use of 2,4-D, dicamba, glufosinate, and glyphosate in North American cropping systems requires research on herbicide interactions and alternative herbicides or methods for controlling multiple HR crop volunteers.
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Hulugalle, N. R., P. C. Entwistle, F. Scott, and J. Kahl. "Rotation crops for irrigated cotton in a medium-fine, self-mulching, grey Vertosol." Soil Research 39, no. 2 (2001): 317. http://dx.doi.org/10.1071/sr00035.
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Many cotton growers sow rotation crops after irrigated cotton (Gossypium hirsutum L.), assuming that they will improve soil quality and maintain profitability of cotton. Wheat (Triticum aestivum L.) is the most common rotation crop, although more recently, legumes such as faba bean (Vicia Faba L.) and chickpea (Cicer arietinum L.) have come into favour. This paper reports data on soil quality (organic C, nitrate-N, soil structure), yield (cotton lint and rotation crop grain yield, fibre quality), economic returns (gross margins/ha, gross margins/ML irrigation water), and management constraints from an experiment conducted from 1993 to 1998 near Wee Waa, north-western New South Wales, Australia. The soil is a medium-fine, self-mulching, grey Vertosol. The cropping sequences used were cotton followed by N-fertilised wheat (urea at 140 kg N/ha in 1993; 120 kg N/ha thereafter), unfertilised wheat, and unfertilised grain legumes (chickpea in 1993; faba bean thereafter), which were either harvested or the grain incorporated during land preparation. Soil organic C in the 0—0.6 m depth was not affected by the rotation crop, although variations occurred between times of sampling. Regression analysis indicated that there had been no net gain or loss of organic C between June 1993 and October 1998. Sowing leguminous rotation crops increased nitrate-N values. A net increase in root-zone nitrate-N reserves occurred with time (from June 1993 to October 1998) with all rotation crops. Soil compaction (measured as specific volume of oven-dried soil) was lower with wheat by October 1998. A net decrease in soil compaction occurred in the surface 0.15 m with all rotation crops between 1993 and 1998, whereas it increased in the 0.15–0.60 m depth. Cotton lint yield and quality, and gross margins/ha and gross margins/ML, were always higher where wheat was sown, with highest gross margins occurring when N fertiliser was applied. Applying N fertiliser to wheat did not significantly increase cotton lint yield and fibre quality, but increased gross margins of the cotton–wheat sequence due to higher wheat yield and protein percentage. Lint yield and fibre quality were decreased by sowing leguminous rotation crops. Management constraints such as lack of effective herbicides, insect damage, harvesting damage, and availability of suitable marketing options were greater with legumes than with wheat. Overall, wheat was a better rotation crop than grain legumes for irrigated cotton.
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Cherkashin, V. N., G. V. Cherkashin, and V. A. Kolomytseva. "Influence of damage of cotton bollworm on the structure of the corn crop." Agrarian science 344, no. 1 (March 13, 2021): 85–89. http://dx.doi.org/10.32634/0869-8155-2021-344-1-85-89.
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Corn is one of the leading field crops in the Stavropol region. It is sown for grain annually on an area of about 120 thousand hectares. Many farms use it as a monoculture, sowing in one place for 3–4 years in a row. This makes it possible for the main pest of maize, the cotton bollworm, to stably maintain its population in field crop rotations for many years, not only in corn crops, but also to spread to other crops. The article provides information on the morphology, biological features of the cotton bollworms development in corn crops.
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Li, Yunhe, Eric M. Hallerman, Kongming Wu, and Yufa Peng. "Insect-Resistant Genetically Engineered Crops in China: Development, Application, and Prospects for Use." Annual Review of Entomology 65, no. 1 (January 7, 2020): 273–92. http://dx.doi.org/10.1146/annurev-ento-011019-025039.
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With 20% of the world's population but just 7% of the arable land, China has invested heavily in crop biotechnology to increase agricultural productivity. We examine research on insect-resistant genetically engineered (IRGE) crops in China, including strategies to promote their sustainable use. IRGE cotton, rice, and corn lines have been developed and proven efficacious for controlling lepidopteran crop pests. Ecological impact studies have demonstrated conservation of natural enemies of crop pests and halo suppression of crop-pest populations on a local scale. Economic, social, and human health effects are largely positive and, in the case of Bt cotton, have proven sustainable over 20 years of commercial production. Wider adoption of IRGE crops in China is constrained by relatively limited innovation capacity, public misperception, and regulatory inaction, suggesting the need for further financial investment in innovation and greater scientific engagement with the public. The Chinese experience with Bt cotton might inform adoption of other Bt crops in China and other developing countries.
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Kumar, Sandeep, Arpit Jain, Anand Prakash Shukla, Satyendr Singh, Rohit Raja, Shilpa Rani, G. Harshitha, Mohammed A. AlZain, and Mehedi Masud. "A Comparative Analysis of Machine Learning Algorithms for Detection of Organic and Nonorganic Cotton Diseases." Mathematical Problems in Engineering 2021 (June 16, 2021): 1–18. http://dx.doi.org/10.1155/2021/1790171.
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Cotton is the natural fiber produced, and the commercial crop grown in monoculture on 2.5% of total agricultural land. Cotton is a drought-resistant crop that provides a reliable income to the farmers that grow under the area with a threat from climatic change. These cotton crops are being affected by bacterial, fungal, viral, and other parasitic diseases that may vary due to the climatic conditions resulting in the crop’s low productivity. The most prone to diseases is the leaf that results in the damage of the plant and sometimes the whole crop. Most of the diseases occur only on leaf parts of the cotton plant. The primary purpose of disease detection has always been to identify the diseases affecting the plant in the early stages using traditional techniques for better production. To detect these cotton leaf diseases appropriately, the prior knowledge and utilization of several image processing methods and machine learning techniques are helpful.
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Boltayev, Botir, and Sanjar Boltayev. "Management methods of harmful pests in the cotton-wheat crop rotation system." E3S Web of Conferences 244 (2021): 02049. http://dx.doi.org/10.1051/e3sconf/202124402049.
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This article analyzed the ecological succession between pests of crops as a result of the transition from the traditional cotton-alfalfa crop rotation system to the cotton-grain crop rotation system. It was found that the species composition, development and propagation characteristics of harmful organisms in the weeds around the field, as well as in the intermediate crops, can be reduced by up to 60-70%, and protected entomophagous organisms from the destructive effects of pesticides through lateral tillage of the 30-meter edge of the cotton crop. Furthermore, it was possible to apply biological methods to the remaining 70-80% of the field. It was necessary to properly organize the system of crop rotation “Cotton-grain” towards naturally controlling (reduce or eliminate) the number of harmful organisms (pests, diseases and weeds) in the agrophytocenosis. It was observed that diseases (especially rust), weeds (especially wild oats, raygras), pests (weeds, wheat thrips, slime,) were 2-3 times less in the grain planted after cotton, the number of spiders in the cotton field planted after grain were 3-4 times less, and diseases were decreased by 25-30%.
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Hereward, James P., Paul J. DeBarro, and Gimme H. Walter. "Resolving multiple host use of an emergent pest of cotton with microsatellite data and chloroplast markers (Creontiades dilutus Stål; Hemiptera, Miridae)." Bulletin of Entomological Research 103, no. 5 (May 23, 2013): 611–18. http://dx.doi.org/10.1017/s0007485313000291.
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AbstractFollowing the global uptake of transgenic cotton several Hemipteran pests have emerged as primary targets for pesticide control. Previous research on one such emergent pest: the green mirid, Creontiades dilutus, indicated differential use of two crop hosts, cotton (Gossypium hirsutum, Malvaceae) and lucerne (alfalfa) (Medicago sativa, Fabaceae). We tested the hypothesis that this apparent demographic independence of lucerne and cotton inhabiting mirids is the result of cryptic species being associated with these two crops. We assessed gene flow using microsatellite markers across adjacent cotton and lucerne crops at three geographically separated sites (up to 900 km apart). We also analysed the recent feeding behaviour of these insects by amplifying chloroplast markers from their gut contents. We find high gene flow between these two crops (mean pair wise FST between host plants=0.0141 within localities), and no evidence of cryptic species. Furthermore, the gut analyses revealed evidence of substantial recent movement between these two crops. We discuss the implications of these results for interpreting multiple host use in this species and setting future research priorities for this economically important pest.
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Martinelli, S., P. L. Clark, M. I. Zucchi, M. C. Silva-Filho, J. E. Foster, and C. Omoto. "Genetic structure and molecular variability of Spodoptera frugiperda (Lepidoptera: Noctuidae) collected in maize and cotton fields in Brazil." Bulletin of Entomological Research 97, no. 3 (May 24, 2007): 225–31. http://dx.doi.org/10.1017/s0007485307004944.
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AbstractThe purpose of this research was to evaluate the genetic similarity and structure of the fall armyworm, Spodoptera frugiperda (J.E. Smith), populations associated with maize and cotton crops in Brazil using amplified fragment length polymorphisms. Mean genetic similarity among populations was 0.45. The unweighted pair group method with arithmetic mean analysis dendrograms did not separate populations of S. frugiperda into clusters related to the host plant in which the insects were collected. No genetic variation was observed among maize and cotton populations of S. frugiperda, suggesting that the same populations are injuring both crops in Brazil. This research validates the need for stewardship of crop-protection methods for managing S. frugiperda to reduce the incidence of pesticide resistance, due to the spatial and temporal overlapping of maize and cotton crops in some regions in Brazil.
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Tabashnik, Bruce E., and Yves Carrière. "Global Patterns of Resistance to Bt Crops Highlighting Pink Bollworm in the United States, China, and India." Journal of Economic Entomology 112, no. 6 (June 29, 2019): 2513–23. http://dx.doi.org/10.1093/jee/toz173.
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Abstract Crops genetically engineered to produce insecticidal proteins from Bacillus thuringiensis (Bt) have advanced pest control, but their benefits have been reduced by evolution of resistance in pests. The global monitoring data reviewed here reveal 19 cases of practical resistance to Bt crops, which is field-evolved resistance that reduces Bt crop efficacy and has practical consequences for pest control. Each case represents the responses of one pest species in one country to one Bt toxin. The results with pink bollworm (Pectinophora gossypiella) and Bt cotton differ strikingly among the world’s three leading cotton-producing nations. In the southwestern United States, farmers delayed resistance by planting non-Bt cotton refuges from 1996 to 2005, then cooperated in a program that used Bt cotton, mass releases of sterile moths, and other tactics to eradicate this pest from the region. In China, farmers reversed low levels of pink bollworm resistance to Bt cotton by planting second-generation hybrid seeds from crosses between Bt and non-Bt cotton. This approach yields a refuge of 25% non-Bt cotton plants randomly interspersed within fields of Bt cotton. Farmers adopted this tactic voluntarily and unknowingly, not to manage resistance, but apparently because of its perceived short-term agronomic and economic benefits. In India, where non-Bt cotton refuges have been scarce and pink bollworm resistance to pyramided Bt cotton producing Cry1Ac and Cry2Ab toxins is widespread, integrated pest management emphasizing shortening of the cotton season, destruction of crop residues, and other tactics is now essential.
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Reeves, D. Wayne, Andrew J. Price, and Michael G. Patterson. "Evaluation of Three Winter Cereals for Weed Control in Conservation-Tillage Nontransgenic Cotton." Weed Technology 19, no. 3 (September 2005): 731–36. http://dx.doi.org/10.1614/wt-04-245r1.1.
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The increased use of conservation tillage in cotton production requires that information be developed on the role of cover crops in weed control. Field experiments were conducted from fall 1994 through fall 1997 in Alabama to evaluate three winter cereal cover crops in a high-residue, conservation-tillage, nontransgenic cotton production system. Black oat, rye, and wheat were evaluated for their weed-suppressive characteristics compared to a winter fallow system. Three herbicide systems were used: no herbicide, preemergence (PRE) herbicides alone, and PRE plus postemergence (POST) herbicides. The PRE system consisted of pendimethalin at 1.12 kg ai/ha plus fluometuron at 1.7 kg ai/ha. The PRE plus POST system contained an additional application of fluometuron at 1.12 kg/ha plus DSMA at 1.7 kg ai/ha early POST directed (PDS) and lactofen at 0.2 kg ai/ha plus cyanazine at 0.84 kg ai/ha late PDS. No cover crop was effective in controlling weeds without a herbicide. However, when black oat or rye was used with PRE herbicides, weed control was similar to the PRE plus POST system. Rye and black oat provided more effective weed control than wheat in conservation-tillage cotton. The winter fallow, PRE plus POST input system yielded significantly less cotton in 2 of 3 yr compared to systems that included a winter cover crop. Use of black oat or rye cover crops has the potential to increase cotton productivity and reduce herbicide inputs for nontransgenic cotton grown in the Southeast.
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Grey, Timothy L., L. Bo Braxton, and John S. Richburg. "Effect of Wheat Herbicide Carryover on Double-Crop Cotton and Soybean." Weed Technology 26, no. 2 (June 2012): 207–12. http://dx.doi.org/10.1614/wt-d-11-00143.1.
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In the southeastern United States many farmers double-crop winter wheat with soybean or cotton. However, there is little information about residual injury of herbicides used in wheat to these rotational crops. Experiments were conducted from 2007 to 2008 and 2008 to 2009 in soft red winter wheat to evaluate response of rotational crops of soybean and cotton after application of various acetolactate synthase herbicides in wheat. Pyroxsulam, mesosulfuron, sulfosulfuron, propoxycarbazone, or chlorsulfuron plus metsulfuron at multiple rates were applied to wheat approximately 110 to 120 d before planting rotational crops. Soils were Tift loamy sand at Ty Ty, GA and Faceville sandy loam at Plains, GA. After wheat harvest, soybean (‘Pioneer 97M50’) and cotton (‘DP 0949 B2RF’) were strip-tillage planted and evaluated for injury, stand density, height over time, and yields. For both locations, wheat was tolerant to all herbicide treatments with little to no visible injury 7 to 90 d after application. Pyroxsulam injury was less than sulfosulfuron or mesosulfuron. At recommended use rates, wheat injury was transient with no effect on yield. Double-crop soybean for both locations had no differences in stand establishment for any herbicide treatments. There was significant carryover injury to soybean and cotton for sulfosulfuron applied to wheat for the Faceville sandy loam. There was no effect of herbicide treatment on cotton stand. There was little to no difference in residual activity on rotational crops between pyroxsulam and other wheat herbicides when labeled rates were applied. This is significant as pyroxsulam is used to control Italian ryegrass and wild radish in this region.
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AREAL, F. J., L. RIESGO, and E. RODRÍGUEZ-CEREZO. "Economic and agronomic impact of commercialized GM crops: a meta-analysis." Journal of Agricultural Science 151, no. 1 (February 28, 2012): 7–33. http://dx.doi.org/10.1017/s0021859612000111.
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SUMMARYThe present paper presents a meta-analysis of the economic and agronomic performance of genetically modified (GM) crops worldwide. Bayesian, classical and non-parametric approaches were used to evaluate the performance of GM crops v. their conventional counterparts. The two main GM crop traits (herbicide tolerant (HT) and insect resistant (Bt)) and three of the main GM crops produced worldwide (Bt cotton, HT soybean and Bt maize) were analysed in terms of yield, production cost and gross margin. The scope of the analysis covers developing and developed countries, six world regions, and all countries combined. Results from the statistical analyses indicate that GM crops perform better than their conventional counterparts in agronomic and economic (gross margin) terms. Regarding countries’ level of development, GM crops tend to perform better in developing countries than in developed countries, with Bt cotton being the most profitable crop grown.
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Mandal, B. K., R. K. Ghosh, N. C. Das, and A. K. Som Choudhury. "Studies on Cotton-based Multiple Cropping." Experimental Agriculture 23, no. 4 (October 1987): 443–49. http://dx.doi.org/10.1017/s0014479700017403.
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SUMMARYStudies were carried out at Kalyani during 1982–83 and 1983–84 to evolve a multiple cropping system with cotton as the main crop. Cotton was intercropped with paddy, greengram, blackgram, peanut and soyabean in the rainy season, and these were also grown as solccrops followed by crops of peanut, lentil, chickpea, wheat and mustard, respectively, in the winter season. All plots were subsequently cropped with sesame in the summer season. There was an increase in total grain yield, land equivalent ratio (LER), area time equivalent ratio (ATER) and relative net return (RNR) values when legumes and cereals were intercropped with cotton. The yield of the winter crops grown with the help of residual soil moisture was in the order: chickpea > mustard > lentil > wheat > peanut. Sesame yielded best after the chickpea and blackgram sequence and yielded almost as well after the lentil and greengram. The greatest net return was obtained from the cotton and paddy (1:1) intercrop followed by sesame.
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Bundy, C. Scott, and R. M. McPherson. "Cropping Preferences of Common Lepidopteran Pests in a Cotton/Soybean Cropping System." Journal of Entomological Science 42, no. 1 (January 1, 2007): 105–18. http://dx.doi.org/10.18474/0749-8004-42.1.105.
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Two soybean varieties (an early-maturing Group V and a later-maturing Group VII) and two cotton varieties (a conventional and a transgenic Bacillus thuringiensis Berliner [Bt]) were grown in adjacent replicated large field plots at two locations for 3 growing seasons. The abundance of commonly-observed lepidopteran pests within these two crops was observed weekly throughout each growing season. The green cloverworm, Hypena scabra (F.); soybean looper, Pseudoplusia includens (Walker), and; velvetbean caterpillar, Anticarsia gemmatalis Hübner, preferred soybeans over cotton at all six test sites. The bollworm complex, Helicoverpa zea (Boddie) and Heliothis virescens (F.), preferred soybeans at one site, cotton at two sites, and no crop preference at three sites. There was no difference in the seasonal mean abundance of the pests between the two soybean maturity groups. A few varietal differences were noted on soybeans on specific sampling dates; however, they occurred when insect numbers were low. Population densities approached economic injury levels on both the early and later-maturing soybean varieties. In cotton, the bollworm complex was significantly more abundant in conventional cotton than in Bt cotton. Although soybean loopers are a pest of both crops, soybeans are preferred when they are planted adjacent to cotton. Given this behavioral response, soybeans might serve as a trap crop to attract soybean loopers into a small planting of soybeans and out of the major planting of cotton.
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Bange, Michael P., Sarah J. Caton, and Stephen P. Milroy. "Managing yields of high fruit retention in transgenic cotton (Gossypium hirsutum L.) using sowing date." Australian Journal of Agricultural Research 59, no. 8 (2008): 733. http://dx.doi.org/10.1071/ar07423.
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Recently, genetically engineered (transgenic) cottons expressing genes from Bacillis thuringiensis (Bt) have been made available to cotton growers throughout the world. In Australia, cotton growers have access to Bt cotton that contains genes expressing the insecticidal proteins Cry1Ac and Cry2Ab (Bollgard II®). Bollgard II offers significant potential to reduce pesticide use for the control of major Lepidopteran pests (particularly Helicoverpa spp. in Australia). As a consequence of the improved insect control, retention of squares (flower buds) and young bolls is higher in Bollgard II varieties than in non-Bollgard varieties. A concern raised by Australian cotton growers is that in some regions, yield potential for Bollgard II may be limited because the demands of earlier high fruit retention reduce resources for continued growth and fruiting, thus leading to earlier maturity and reduced yield. Non-Bollgard crops with high early retention are known to mature earlier sometimes reducing yield. Three field experiments over three seasons, which varied sowing date and compared non-Bollgard II and Bollgard II cotton cultivars, were conducted to test the hypothesis that delaying sowing date in Bollgard II will increase canopy size (without delaying crop development) and alleviate the potential concerns for the effect of higher fruit retention reducing canopy size and the time to maturity, limiting the yield of Bollgard II. In non-Bollgard II crops, larger canopies resulting from early loss of fruit or apical meristem damage can support more fruit growth for longer, provided season length allows fruit to mature. Results showed that delayed sowing did not increase the yield of the Bollgard II cultivar through increased leaf area index at flowering compared with normal sowing dates. However, in comparison with the conventional cultivar, which had yields that became lower with later sowings, Bollgard II maintained its yield presumably through the shorter fruiting cycle (because of its consistently higher earlier fruit retention), allowing time to support growth of the same number of bolls as earlier sowings. Improvements in fibre quality were also recorded with later sowings for both cultivars. Varying sowing dates for Bollgard II in different production regions may offer opportunities for Australian growers to help optimise yield, fibre quality, and reduce risks associated with poor crop establishment when crops are sown too early.
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Bloodworth, L. H., and J. R. Johnson. "Cover Crops and Tillage Effects on Cotton." Journal of Production Agriculture 8, no. 1 (January 1995): 107–12. http://dx.doi.org/10.2134/jpa1995.0107.
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VIDAL, VITOR MARQUES, FREDERICO ANTONIO LOUREIRO SOARES, MARCONI BATISTA TEIXEIRA, ANTONIO EVAMI CAVALCANTE SOUSA, and FERNANDO NOBRE CUNHA. "POTASSIUM FERTILIZATION AND SOIL MANAGEMENT SYSTEMS FOR COTTON CROPS." Revista Caatinga 30, no. 3 (September 2017): 568–77. http://dx.doi.org/10.1590/1983-21252017v30n304rc.
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ABSTRACT Cotton has great socio-economic importance due to its use in textile industry, edible oil and biodiesel production and animal feed. Thus, the objective of this work was to identify the best potassium rate and soil management for cotton crops and select among cultivars, the one that better develops in the climatic conditions of the Cerrado biome in the State of Goiás, Brazil. Thus, the effect of five potassium rates (100, 150, 200, 250 and 300 kg ha-1 of K2O) and two soil management systems (no-till and conventional tillage) on the growth, development and reproduction of four cotton cultivars (BRS-371, BRS-372, BRS-286 and BRS-201) was evaluated. The data on cotton growth and development were subjected to analysis of variance; the data on potassium rates were subjected to regression analysis; and the data on cultivars and soil management to mean test. The correlation between the vegetative and reproductive variables was also assessed. The conventional tillage system provides the best results for the herbaceous cotton, regardless of the others factors evaluated. The cultivar BRS-286 has the best results in the conditions evaluated. The cultivar BRS-371 under no-till system present the highest number of fruiting branches at a potassium rate of 105.5% and highest number of floral buds at a potassium rate of 96.16%. The specific leaf area was positively correlated with the number of bolls per plant at 120 days after emergence of the herbaceous cotton.
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Guntukula, Raju, and Phanindra Goyari. "Climate Change Effects on the Crop Yield and Its Variability in Telangana, India." Studies in Microeconomics 8, no. 1 (May 29, 2020): 119–48. http://dx.doi.org/10.1177/2321022220923197.
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This study has examined the effects of climatic factors on mean yields and yield variability of four primary crops (rice, cotton, jowar and groundnut) in Telangana state by applying the Just and Pope production function over a period of 1956–2015. Using the three-stage feasible generalised least squares estimation procedure, we have estimated the production function of four crops. The empirical results have revealed that the effects of changes in climatic factors vary among crops under study. Maximum temperature has a significant adverse effect on rice, cotton and groundnut yields. Minimum temperature has a substantial positive effect on rice, cotton and groundnut. Further, rainfall is adversely related to cotton and groundnut yields. Maximum temperature has appeared as a risk-reducing factor for all study crops while minimum temperature as a risk-enhancing factor for rice, cotton and jowar. Lastly, rainfall has been found as a risk-enhancing factor for rice and groundnut whereas it is a risk-reducing factor for jowar and cotton. Results from the study have important implications on how Telangana’s farming sector will adapt to climate variability and change for sustainable agricultural development. JEL Codes: C23, Q18, Q51, Q54
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Jolly, Curtis, Kenrett Y. Jefferson-Moore, and Greg Traxler. "Consequences of Biotechnology Policy for Competitiveness and Trade of Southern U.S. Agriculture." Journal of Agricultural and Applied Economics 37, no. 2 (August 2005): 393–407. http://dx.doi.org/10.1017/s1074070800006866.
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The effect of policy decisions on the competitiveness of genetically modified (GM) crops was examined. The United States has been an early innovator in the development and use of biotechnology crops and has expanded its export market share of the three major GM crops: soybeans, cotton, and corn. Cotton, soybeans, and corn are all grown in the southern states, but these states have an apparent comparative advantage only in the production of cotton, which may be strengthened with the adoption of genetically modified cotton. The influence of biotechnology on the competitiveness of soybeans and corn for the southern states through the introduction of genetically modified organisms (GMOs) is not clear but is probably negligible.
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Flanders, Archie, Fred C. White, W. Don Shurley, and Steve M. Brown. "Profit and Variance Analysis of Cotton Production Technologies and Rotation Crops in Georgia." Journal of Agricultural and Applied Economics 35, no. 3 (December 2003): 685–94. http://dx.doi.org/10.1017/s1074070800028388.
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Genetically modified cotton varieties have the potential for increasing returns and/or decreasing labor requirements. A nonlinear optimization model is applied to a whole farm analysis for evaluating cotton production technologies. This model maximizes farm utility, composed of expected returns and their variability, at various risk aversion levels in order to evaluate cotton production technologies. Results show that while conventional cotton maximizes utility in a risk-neutral situation, transgenic cotton varieties entered into the optimal solution as higher levels of risk aversion were considered.
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Luo, Ming Yun, and Hui Chen. "Study on Potential Impacts of Genetically Modified Cultivation on Soil Physical and Chemical Properties." Advanced Materials Research 610-613 (December 2012): 3005–12. http://dx.doi.org/10.4028/www.scientific.net/amr.610-613.3005.
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With the application and promotion of genetically modified crops, the safe of Bt-transgenic crops on soil had become one of the hot spot. In present study, two parallel experiments were conducted to compare the impacts of transgenic cotton on the rhizosphere soil properties in northern China. The results showed that the pH value increased, except for the cotton 33B. Furthermore, the change extent varied with Bt transgenic cotton and non Bt cotton. In addition, organic total carbon、 total nitrogen and available nitrogen decreased, while these of GK-12 increased. In general, the effect was different from cotton cultivar. Available P and K in the rhizosphere zone increased among all cotton cultivars tested, and no significant difference was found between Bt and non-Bt cotton
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Brown, Steven M., and Ted Whitwell. "Weed Control Programs for Minimum-Tillage Cotton (Gossypium hirsutum)." Weed Science 33, no. 6 (November 1985): 843–47. http://dx.doi.org/10.1017/s0043174500083478.
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Eleven herbicide systems were evaluated from 1981 to 1983 for cotton (Gossypium hirsutumL. ‘Stoneville 825’) planted no-till directly into cover crops or winter fallow and for cotton planted following conventional tillage. Herbicide systems consisted of paraquat (1,1’-dimethyl-4,4’-bipyridinium ion) or glyphosate [N-(phosphonomethyl)glycine] and/or residual herbicides applied prior to crop emergence. Some systems also included early postemergence or postemergence-directed applications. Cover crops were crimson clover (Trifolium incarnatumL.), hairy vetch (Vicia villosaRoth.), and rye (Secale cerealeL.). Soil cover in fallow treatments was comprised mainly of cotton stalk residue. Conventional tillage and seedbed preparation included fall moldboard plowing and spring disking/smoothing. Treatments were maintained in the same site each year. Order of cover crop susceptibility to herbicides applied prior to crop emergence was rye>clover>vetch. In 1981, all residual treatments except cyanazine {2-[[4-chloro-6-(ethylamino)-1,3,5-triazin-2-yl]amino]-2-methylpropanenitrile} alone prior to crop emergence provided better than 80% control of annual weeds. In subsequent years only systems that included applications prior to crop emergence and postemergence-directed herbicides provided acceptable control. From 1981 to 1983, annual grasses increased 20- to 100-fold for systems in which control was poor. Weed control was generally superior in conventional tillage. Vetch adversely affected cotton stands in all 3 yr. Also, in 1982, reduced cotton stands resulted from cyanazine treatments applied prior to crop emergence in clover, vetch, and fallow. Cotton yields were affected by cover dessication, annual weed control, and cotton stands. Buildup of annual weeds reduced yields to near zero for some treatments in 1983.
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Ali, Mubarik. "The Price Response of Major Crops in Pakistan: An Application of the Simultaneous Equation Model." Pakistan Development Review 29, no. 3-4 (September 1, 1990): 305–25. http://dx.doi.org/10.30541/v29i3-4pp.305-325.
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This paper specifies a model to simultaneously estimate the price response, assuming an interdependence among crops. The model is applied to estimate ownand cross-price elasticities of five major crops in Pakistan, viz., wheat, cotton, rice, sugan:ane, and maize based on the production and expected wholesal~price data for the period 1957-86. The study found little potential to· enhance overall agricultural productivity by ir.:reasing the single crop price, sillCe either the ownprice elasticities were low or, otherwise, the nagative cross-price effec ts on the production of other crops were high. However, a 100percent system at;; improv~ ment in terms of trade for agriculture will illCrease overall agricultural productivity by about 6 percent in the long run.
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White, Randall H., and A. Douglas Worsham. "Control of Legume Cover Crops in No-Till Corn (Zea mays) and Cotton (Gossypium hirsutum)." Weed Technology 4, no. 1 (March 1990): 57–62. http://dx.doi.org/10.1017/s0890037x00024982.
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Eight herbicide treatments per crop were evaluated for hairy vetch and crimson clover cover-crop control in no-till corn and cotton at two locations in North Carolina. Paraquat alone or combined with dicamba, 2,4-D, or cyanazine, and cyanazine alone, controlled clover the best in both crops. All herbicide treatments, except glyphosate alone, controlled at least 89% of hairy vetch in corn. However, only 2,4-D and cyanazine alone or combined with glyphosate controlled greater than 89% of hairy vetch in cotton. Except for poor control of hairy vetch and crimson clover by glyphosate alone, reduced legume control did not consistently decrease corn or cotton yield. Weed control was reduced in crimson clover treated with glyphosate alone, but control was similar among the remaining herbicide treatments. Effectiveness of legume control did not influence the N concentration of corn or cotton. Corn stand, height, and yield were greater in hairy vetch than in crimson clover. Seed cotton yield did not differ between vetch and clover.
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Maboudou Alidou, Guirguissou, and Anke Niehof. "Responses of Rural Households to the Cotton Crisis in Benin." Sustainability 12, no. 10 (May 21, 2020): 4207. http://dx.doi.org/10.3390/su12104207.
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Relying on one source of income puts the livelihood system of rural households at risk. In Benin, cotton has long been the core cash crop of rural livelihood systems—until the mid-2000s, when multiple constraints led to the demise of cotton production. This paper investigates the responses of rural households to the economic shock resulting from the collapse of the cotton sector and the consecutive decrease of income from cotton. The primary data collection was carried out between 2009 and 2012 and included a household survey and focus group discussions with groups of farmers. The results reveal that households diversified their sources of income on farm, with food crops increasingly gaining a cash function. However, because the production system still depended heavily on cotton for access to fertilizers and other inputs for food crops, farmers continued to grow cotton despite its decreasing returns. In addition, because of their multiple extra-domestic activities, women seemed to be less vulnerable than men when coping with livelihood shocks; indeed, their contribution to providing for household needs increased. Further results revealed that young men devised their own ways of dealing with the crisis by temporary migration.
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Duffy, Patricia A., Kasazi Shalishali, and Henry W. Kinnucan. "Acreage Response Under Farm Programs for Major Southeastern Field Crops." Journal of Agricultural and Applied Economics 26, no. 2 (December 1994): 367–78. http://dx.doi.org/10.1017/s1074070800026298.
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AbstractAn expected utility model that includes output price and yield uncertainty was used to estimate cotton, com, and soybean acreage response equations for the Southeast. The model appeared to fit the soybean and corn data well, resulting in own-price elasticity estimates of 0.317 for com and 0.727 for soybeans. When applied to cotton acreage, however, the model did not yield satisfactory results. When elasticity was allowed to change over time, however, statistical results for the cotton equation improved, yielding an own-price elasticity of 0.915 at data means.
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Wilson, L. J., and R. Morton. "Seasonal abundance and distribution of Tetranychus urticae (Acari: Tetranychidae), the two spotted spider mite, on cotton in Australia and implications for management." Bulletin of Entomological Research 83, no. 2 (June 1993): 291–303. http://dx.doi.org/10.1017/s0007485300034787.
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AbstractThe two spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is a pest of cotton in Australia yet has received little attention. To develop sampling strategies for pest management the seasonal abundance and intra-crop distribution of T. urticae on cotton was studied. T. urticae colonized cotton crops at seedling emergence in October. Populations declined through November/December then increased progressively thereafter, at varying times and rates. Higher initial infestation levels were correlated with earlier, potentially more damaging, mite outbreaks. Survival of T. urticae through November/December appears crucial in determining the extent to which this potential is realized. Nodes 3 to 5 below the terminal were most heavily infested and should be used as the sampling unit for mites. The within plant distribution of T. urticae was unaffected by cotton variety or insecticide applications. T. urticae was more abundant on the edges of fields than in the interior early in the season (October and November) indicating colonization from an external source. The edge effect diminished with time, suggesting a lack of continuous colonization. The only exceptions to this pattern occurred when T. urticae migrated from senescent maize crops into the nearby cotton crops in early January. A simple sampling technique, based on the presence or absence of mites on leaves was developed for pest management purposes.