Добірка наукової літератури з теми "Late pruning"

The effects of late summer, fall, and winter pruning on the cold hardiness of × Cupressocyparis leylandii (A.B. Jacks. and Dallim.) Dallim. and A.B. Jacks. `Hag gerston Gray' (Leyland cypress) and Lagerstroemia L. `Natchez' (crape myrtle) were determined. Pruning in late summer through early winter significantly reduced the cold hardiness of both taxa. The maximum difference in cold hardiness between pruned trees and controls for × Cupressocyparis leylandii `Haggerston Gray' in October, December, January, and February was 3, 3, 2, and 6C, respectively. The maximum difference in cold hardiness between pruned plants and controls for Lagerstroemia `Natchez' in December, January, and February was 3, 4, and 2C, respectively. Early spring pruning of Leyland cypress and late winter or early spring pruning of crape myrtle are suggested from these data.

Macadamia (Macadamia integrifolia, M. integrifolia × M. tetraphylla) trees were pruned at different times at sites near Alstonville, northern New South Wales, Australia, to examine the effects on vegetative flushing, subsequent flower raceme production and yield. Pruning of cv. 849 and cv. A268 modified the cycle of flush development. Pruning times that resulted in immature flushes on the canopy in late autumn or early winter inhibited raceme production. In contrast, pruning in late May and early June did not generally reduce raceme production relative to production on unpruned trees. The times of pruning that reduced raceme production also reduced yield. The yields of trees pruned in late May were also reduced, presumably because of decreased light interception. In the season after treatment the trees pruned in early April had greater numbers of racemes per unit of tree canopy volume than the trees pruned in late May. The trees of the lighter flowering cv. 849 pruned in early April had higher yield efficiencies than the trees pruned in late May, whereas there was no effect on yield efficiency in the prolifically flowering cv. A268. The differences in raceme production in the season after pruning may have been due to a combination of an alternate bearing response, characteristics of the stems produced after pruning, or maturity of the flushes. In a separate experiment, uniconazole sprays immediately after pruning reduced the length of the new stems, slowed canopy expansion, and increased kernel recovery compared with untreated hedged trees, but did not affect flowering or yield. In another experiment, hedging in early June had no effect on raceme production in cv. 849 trees in consecutive seasons, and no effect on canopy volume or yield in the first season. In contrast, canopy volume and yield were reduced in the second season. Finally, pruning of young, yet-to-flower cv. 849 trees from late winter to spring staggered flush development, with the earliest pruned trees producing more racemes and setting more fruit than the later pruned trees.

Abstract Mature ‘Sunqueen’ peach [Prunus persica (L.) Batsch] trees were dormant pruned in March, summer pruned in late July, or summer topped in late July for 3 consecutive years. Pruning and fruit thinning costs were lower for summer topped trees than for dormant or summer pruned trees. Yield, fruit size, and crop value were reduced by summer topping, compared to dormant pruning and summer pruning. When results were combined for 1982 and 1983, the crop value, minus pruning and thinning costs, was $16,749, $16,389, and $14,854/ha for dormant pruned, summer pruned, and summer topped trees, respectively.

Summer pruning increases canopy light penetration and re-exposes spur leaves of the interior canopy of apple trees (Malus ×domestica Borkh.). However, we hypothesized that leaf photosynthetic ability is determined by the pre-pruning light environment, and the re-exposure intensity after summer pruning is incapable of restoring the photosynthesis efficiency of shaded leaves. To test this hypothesis, a commercial-type thinning-cuts pruning was applied to mature central leader `Empire'/M.26 apple trees. Changes in light availability, leaf net photosynthesis (Pn), photosystem II efficiency, and specific leaf weight (SLW) were recorded periodically before and after pruning. Leaf photosynthesis declined slightly through the growing season and was well correlated with pre-pruning light availability until late September. Although Pn decreased more substantially late in the season on exterior leaves than on interior leaves, Pn of leaves in the inner and middle canopies was lower than exterior leaves until late October. Maximum efficiency of photosystem II of dark-adapted leaves, measured by chlorophyll fluorescence (Fv/Fm), was not related to prior exposure or re-exposure. Specific leaf weight was well correlated with pre-pruning light availability and with leaf Pn in August but not in October. Results suggested that commercial summer pruning significantly increases light environments in the inner and middle canopies. However, light availability at interior and middle canopy sites was still much lower than exterior canopy and, consequently, leaf photosynthetic ability did not increase after summer pruning.

Minimal dormant pruning after the first and second growing seasons, followed by standard pruning thereafter, improved total tree yield in the 3rd, 4th, and 5th years after planting. Trees that were pruned in accordance with standard local practice had ≈50% yield compared to minimally pruned trees in years 3 through 5. Fruit from minimally pruned trees was sgnificantly smaller, but mathematical adjustment of crop load indicated that overall yield efficiency was improved in the 3rd and 4th years for trees receiving minimal pruning.

SUMMARYThe economics of coffee plantations is intrinsically linked to pruning, which can improve the canopy architecture and thereby increase productivity. However, recommended pruning times on conilon coffee plantations have been made on an entirely empirical basis. In this study, by evaluating growth, photosynthetic gas exchanges, starch accumulation and crop productivity, the effects of pruning at different times between harvest and flowering were investigated for six conilon coffee clones with distinct stages of fruit maturation (early, intermediate and late). Clones with an early maturation stage were pruned at four different times: 0, 30, 60 and 90 days after harvest (DAH). Intermediate clones were pruned at 0, 30 and 60 DAH, and late clones were pruned at 0 and 30 DAH. Overall, the rates of shoot growth and net photosynthesis, the stomatal conductance and the crop yield were not affected by the pruning treatments in any of the clones. In addition, pruning times did not affect the concentrations of starch or the photochemical efficiency of photosystem II. The carbon isotope composition ratio was marginally affected by the treatments. These results suggest that the pruning time after harvests is relatively unimportant and pruning operations can be scheduled to optimise the use of labour, which directly impacts the production costs of coffee.

Slender spindle is currently the most widespread pruning system for apple trees in the Czech Republic. However, further modifications of this pruning system have been developed. In this study, two pruning systems were compared in the years 2012 to 2015: slender spindle and modified slender spindle (characterised by ‘click’ pruning). The pruning systems were validated on three varieties, using either winter pruning or winter pruning supplemented with late summer pruning in August. The studied parameters included the average length of annual shoots, increase of trunk cross-sectional area (ITCA), fruit yield per tree, specific yield, average fruit weight, number of fruits and their size in various parts of the tree crown, the number of interventions by pruning and the total weight of the removed biomass. There were no significant differences in most of the parameters mentioned above. Application of the ‘click’ pruning technique over several years significantly increased the number of cuttings but the total biomass removed was lower compared with traditional slender spindle.

In a 2-year study, the temporal development of Cercospora leaf spot (Cercospora depazeoides) and berry yield were evaluated in two production systems (integrated and organic) and in two winter pruning treatments (trees pruned to four and eight scaffolds) in two black elderberry (Sambucus nigra) orchards in Hungary. Under organic production, leaf spot onset occurred 2 to 4 weeks earlier (mid- and late July) in both years and both orchards compared with the integrated program. Disease then continuously progressed until the final assessment date (late September) in both years, reaching a maximum final disease incidence of 15.9% in the integrated system and of 38.2% in the organic system. In general, disease progress after late August was greater on trees pruned to eight scaffolds than on trees pruned to four scaffolds in both production systems. Both final disease incidence and area under the disease progress curves (AUDPC) were significantly lower (P < 0.001) in the integrated treatments compared with organic ones. Across all treatments, both disease measures were significantly (P < 0.05) lower on trees pruned to four scaffolds compared with trees pruned to eight scaffolds. However, when the effect of pruning on final disease incidence and AUDPC was analyzed separately for integrated and organic systems, pruning caused uniformly significant differences in disease development only for the organic system. Berry yield was significantly higher (P < 0.05) in the integrated system compared with the organic system, but pruning showed no significant effect on yield. Overall, pruning to four scaffolds resulted in consistently lower disease development in organic production compared to integrated. Thus, winter pruning may be useful as a Cercospora leaf spot management practice in organic elderberry orchards.

Timing and severity of pruning in a 30-year-old commercial `McFarlin' cranberry (Vaccinium macrocarpon Ait.) bed were studied. Treatments in 1989 and 1990 consisted of early or late pruning and heavy, moderate, light, or no pruning. Yield component data were collected in Fall 1989 and 1990, just before harvest. Time of pruning did not affect yield components. In 1989, the unpruned and lightly pruned vines had a higher total plant fresh weight, fewer berries, higher berry yield, longer and more fruiting uprights, and fewer nonfruiting uprights (U,) compared with moderately or heavily pruned vines. Average length of UN and anthocyanin content of berries in 1989 were not influenced by pruning. In 1990, the effects of pruning severity were similar to 1989. In 1990, unpruned vines had a lower percent fruit set and berries contained less anthocyanin than pruned vines. Annual pruning with conventional systems in use decreases yield.

Made available in DSpace on 2016-04-28T14:58:33Z (GMT). No. of bitstreams: 1 2006- Vlamir Fortes de Azevedo.pdf: 2176373 bytes, checksum: 3bbb1382e86e5d66a9e847d2c49e7275 (MD5) Previous issue date: 2006-02-17
Tomato plants are highly susceptible to a great number of pests and diseases . This is a constraint to organic production, especially under field conditions. New technologies should be developed to improve organic tomato yields and reduce disease incidence. Row spacing and pruning regimes are two aspects which may be targeted to achieve these goals. Since cherry-type tomatoes are small, size variation resulting from pruning, will not significantly affect market value. The objective of this dissertation was to evaluate the effect of the number of stems per plant (through pruning) and plant densities on the yields and fruit quality of cherry-type tomatoes. Also, the labor required to prune the plants was estimated. Two experiments were performed at the experimental field of Departamento de Fitotecnia, Universidade Federal Rural do Rio de Janeiro, Serop?dica-RJ in the Spring-Summer 2004 and Fall/Winter 2005. The first experiment evaluated the effect of three pruning regimes (free growth, one stem per plant and two stems per plant) three plant densities (1.5 X 0,4m,1.5 X 0,6m and 1.5 X 0,8 m) and two cultivars (hybrid Super-Sweet and a local self pollinated - Perinha ). The second evaluated the effects of three pruning regimes (free growth, two stem per plant and three stems per plant and two cultivars (hybrid Super-Sweet and a self pollinated - A ). The spacing used was 1.0 X 0.6m. In the first experiment, fruit yields were equivalent on the free growth and the two stems treatments. The free growth treatment had lower labor cost, since no pruning was done. In the second experiment, the number of harvests was lower compared to the previous experiment, since a severe occurrence of blight occured. Higher yields were achieved on the three stem treatment, although a higher labor cost was associatesd to this treatment.
O tomateiro ? uma esp?cie altamente suscet?vel a um grande n?mero de pragas e doen?as, o que dificulta o seu cultivo em sistemas org?nicos de produ??o, principalmente quando conduzida em ambiente n?o-protegido. Assim, novas tecnologias que possam vir a viabilizar o seu cultivo em sistemas org?nicos devem ser testadas, visando n?o s? o aumento da produ??o, como tamb?m a redu??o dos problemas fitossanit?rios. Entre os fatores que podem ser trabalhados est?o o espa?amento e a elimina??o sistem?tica das hastes laterais, pr?tica esta conhecida como desbrota , deixando-se uma ou mais hastes por planta. Como o grupo do tomate cereja apresenta frutos pequenos, o tamanho do fruto n?o afeta significativamente a sua valoriza??o no mercado. O objetivo do presente trabalho foi avaliar o efeito do n?mero de hastes por planta, combinado com diferentes espa?amentos, sobre a produtividade e a qualidade de frutos de tomate tipo cereja e o gasto com m?o-de-obra para se efetuar a desbrota. Para tanto, foram realizados dois ensaios no Campo Experimental da Horticultura do Departamento de Fitotecnia da Universidade Federal Rural do Rio de Janeiro, em Serop?dica-RJ, nos per?odos de primavera-ver?o de 2004 e outono-inverno de 2005. No primeiro ensaio, foram avaliados os efeitos da combina??o de tr?s formas de condu??o (sem tutoramento e sem limita??o do n?mero de hastes por planta; tutoramento e condu??o de uma haste por planta e, tutoramento e condu??o de duas hastes por planta), tr?s espa?amentos entre plantas (0,4, 0,6 e 0,8 m) e duas cultivares de tomate cereja, o h?brido Super-Sweet e a variedade Perinha . O espa?amento entre linhas utilizado foi 1,5 m. No segundo ensaio, foram avaliados os efeitos da combina??o entre tr?s formas de condu??o (sem tutoramento e sem limita??o do n?mero de hastes por planta; tutoramento e condu??o de duas hastes por planta e, tutoramento e condu??o de tr?s hastes por planta) e duas cultivares de tomate cereja, o h?brido Super-Sweet e variedade A . O espa?amento adotado foi de 0,6 m entre plantas e 1,0 m entre linhas. No cultivo realizado no per?odo de primavera-ver?o, observou-se que o sistema n?o tutorado apresentou produtividade de frutos comerciais igual estatisticamente ? do tratamento onde as plantas foram conduzidas sob tutoramento e mantendo-se duas hastes por planta. O tratamento onde n?o foi feita a condu??o das plantas apresentou, ainda, menor custo de produ??o, decorrente do fato de n?o se ter gasto m?o-de-obra para a pr?tica da desbrota. No cultivo realizado no per?odo de outono-inverno, no entanto, observou-se redu??o acentuada do n?mero de colheitas neste sis tema devido, principalmente, ao ataque severo de requeima. Neste mesmo per?odo, constatou-se que o sistema de condu??o com tr?s hastes foi o que proporcionou maior produtividade de frutos comerciais, por?m com maior custo de produ??o devido ao aumento do gasto com m?o-de-obra para realiza??o da referida opera??o.

Warming is shifting vine phenology, compressing harvests, and altering the balance of fruit traits relevant to wine. The aim of this thesis was to test late pruning as a tool to delay maturity of Shiraz in the Barossa Valley of Australia, and its impact on vine yield, and wine chemical and sensory attributes. Pruning at three phenological stages were compared: winter (control), budburst and 2-3 leaves emerged. Two trials were established. First, three pruning treatments were carried out during four consecutive seasons on the same vines, to evaluate carry-over effects. Second, two thermal regimes (heating with open-top chambers vs unheated control) was combined with three pruning times during three seasons. In general, late pruning treatments delayed maturity with neutral or positive effects for yield and berry traits without carry-over effects on phenology, yield, leaf area and berry traits. Further, late pruning shifted the onset of berry anthocyanin in relation to sugars and increased the anthocyanin to sugar ratio, improved wine phenolics and altered sensory attributes. In a context of warming, delaying pruning until 2-3 leaves have emerged can effectively spread the harvest and partially restore anthocyanin : sugar ratio, improve wine phenolics and preserve wine sensory attributes with no yield penalties.
Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2019

This chapter focuses on French essayist Michel de Montaigne, who is considered a logical point of departure since his account of same-sex relationships is by far the most well known today. It recounts the contended process of Montaigne's Journal de voyage as the abbé Prunis found much of its content distasteful. It also cites a passage in Journal de voyage concerning same-sex marriages in Rome that embarrassed Canon Guillaume-Vivien Leydet, just as parts of the manuscript had embarrassed the abbé Prunis. The chapter discusses Montaigne's anecdote that was intended to surprise and amuse the worldly, cultivated visitor in search of diverse customs and unusual happenings. It highlights the influence of Montaigne's Essais on his early free-thinking readers in the late sixteenth and seventeenth centuries.

This chapter analyses the evolving place of the French Restaurant in London in the first half of the 20^th century, innovations and developments during the inter-war years and the paradoxes of dining out in London during the Second World War. It is divided into three sections: ‘Continuity and Innovation for the French Restaurant in London: the Inter-War Years’; ‘Privation, Plenty and Paradox in the French Restaurant of Second World War London’; ‘The French restaurant as cultural, social and political site: The Free French in London’. It firstly takes particular examples such as the restaurants of Marcel Boulestin and Simone Prunier and the writings of André Simon and the Wine and Food Society to represent the place of French food during London’s interwar years. It then focuses on the dining-out culture in London during the Second World War, and finally on the place of the French restaurant for a new migrant community in London, the Free French who joined de Gaulle from June 1940, bringing changes to the ‘French colony’ established in London since the late 19^th century. The French restaurant in London endured during the period and acquired a new place and identity in London’s restaurant culture.

Network pruning is a widely used technique to reduce computation cost and model size for deep neural networks. However, the typical three-stage pipeline, i.e., training, pruning and retraining (fine-tuning) significantly increases the overall training trails. In this paper, we develop a systematic weight-pruning optimization approach based on Surrogate Lagrangian relaxation (SLR), which is tailored to overcome difficulties caused by the discrete nature of the weight-pruning problem while ensuring fast convergence. We further accelerate the convergence of the SLR by using quadratic penalties. Model parameters obtained by SLR during the training phase are much closer to their optimal values as compared to those obtained by other state-of-the-art methods. We evaluate the proposed method on image classification tasks using CIFAR-10 and ImageNet, as well as object detection tasks using COCO 2014 and Ultra-Fast-Lane-Detection using TuSimple lane detection dataset. Experimental results demonstrate that our SLR-based weight-pruning optimization approach achieves higher compression rate than state-of-the-arts under the same accuracy requirement. It also achieves a high model accuracy even at the hard-pruning stage without retraining (reduces the traditional three-stage pruning to two-stage). Given a limited budget of retraining epochs, our approach quickly recovers the model accuracy.