Components of High-Yielding Cotton Grown in Rain-Fed Conditions in the Brazilian Cerrado

The physiological utility of nitrogen (N) and zinc (Zn) in cotton (Gossypium hirsutum L.) is interlinked, but the level of their contribution to nutritional balance and production remains unexplored. Therefore, this study explored the interactive effects of N and Zn on cotton lint yield, seed yield, and fiber quality under field conditions. The experiment was conducted from 2016 to 2021 within a randomized complete block design replicated five times, testing a full factorial treatment structure with four N rates (34, 67, 101, and 134 kg N ha−1) and four Zn rates (0, 6, 11, and 17 kg Zn ha−1). Overall, cotton lint and seed yield were significantly influenced by the three‐way interaction between N, Zn, and year. Applying just N never resulted in high yield, except in 2017. Each year, applications of 101 kg N ha−1 and 6 kg Zn ha−1 were found to be the optimum rates, and in 2021 this combination resulted in the highest lint (1804 kg ha−1) and seed cotton (4484 kg ha−1) yields, while the lowest lint yield was recorded in 2016 when 34 kg N ha−1 was applied alone. Increasing N rates from 34 to 101 kg N ha−1 reduced micronaire by 6%, while the opposite was observed with Zn. Overall, the synergistic effects of both N and Zn were noted. Lint, seed, and fiber quality responses to N and Zn varied slightly each year, underscoring the annual environmental variations and the need for adaptive nutrient management plans.

Cotton (Gossypium hirsutum L.) growers are motivated to reduce seeding rates due to increased technology fees associated with improved transgenic cotton cultivars. Advances in planting machinery have improved precision of seed metering and seed placement in recent years. A two-year study was conducted to evaluate the effect of seeding rate, planter downforce, and cultivar on crop emergence and lint yield in cotton planted as singulated and hill-drop (two seed hill-1) configuration. Study treatments consisted of two seeding rates (71,660 and 107,490 seed ha-1), two to three planter downforces (0, 445 and 890 N in 2017; 0 and 890 N in 2018) and two cotton cultivars (representing a large-seeded and small-seeded cultivar, 9,259 - 10,582 and 11,244 - 14,330 seed kg-1, respectively) arranged in a strip-split plot design in both seeding configurations. Crop emergence and lint yield in the middle two rows (four-row plots) were measured to evaluate treatment effects among seeding configurations. Results showed that seeding rate and cultivar did not affect (p>0.05) crop emergence and lint yield in both singulated and hill-drop cotton. Crop emergence varied between the two years due to differences in field tillage conditions. Planter downforce affected crop emergence in singulated cotton but not in hill-drop cotton during both years. Field tillage conditions also influenced downforce effect on crop emergence. Selection of an optimal planter downforce had more significant effect (p<0.05) on singulated cotton than hill-dropped cotton. Results showed that large-seeded cultivars can be utilized to attain a high crop emergence early in the season which can help in minimizing production risks associated with poor stand establishment. High seed and technology fees incurred by growers can be effectively reduced by planting lower seeding rates - given an adequate stand establishment is attained using appropriate planter setup including downforce and cultivar selection.

Diaa AE, Ashraf AA, Hashem MA. 2015. Evaluating Bivariate and Multivariate statistical analysis of yield and agronomic characters in Egyptian cotton. Scientia Agriculturae, 9 (3), 150-164. Retrieved from www.pscipub.com (DOI: 10.15192/PSCP.SA.2015.9.3.150164) Two field experiments were conducted in 2009 and 2010 growing seasons at the experimental farm of the Faculty of Agriculture, Cairo University, Giza, Egypt. Sixteen Egyptian cultivars were evaluated in a balanced lattice design (4 x 4) with five replications for nine traits. The aims were to determine relationships between yield and its components and examine the efficiency of such components in building yield capacity by using six different statistical methods. Highly significant differences were detected among genotypes for all studied traits. Highly significant and positive correlation estimates were detected between seed cotton yield and each of number of fruiting branches per plant, number of opening bolls, lint cotton yield per plant, seed cotton yield per plant, lint cotton yield per plot, seed yield per plot and lint percentage. On the other hand, number of dry bolls per plant showed negative association with seed cotton yield. In multiple linear regressions, the relative contribution for all yield components explained 96% of the total variation in seed cotton yield. The stepwise regression showed that, seed yield per plot, lint cotton yield per plot and number of dry bolls, were the most contributing variables in seed cotton yield per feddan (99% of seed cotton yield variation). Stepwise multiple linear regression proved to be more efficient than the full model regression to determine the predictive equation for seed cotton yield. The criteria used in identifying the best subsets were based on monotone functions of the residual sum of squares (RSS) such as R, adjusted R and Mallow’s Cp. Results revealed the best subset regression model, based on the three different criteria, were the predicted equation for seed cotton yield per fed (Y) was Y = -0.12 – 0.011 x2 – 0.011 x6 + 0.016 x7. The simplified results from best subset regression analysis indicate that the highest coefficient of determination (R=99.9%), adjusted R (99.8%) and lowest Mallows' conceptual predictive (Cp) value (2.0), and has three-independent variables. The factor analysis grouped the studied variables into two groups, which explained 83.4% of the total variability in the dependence structure. The first group contributed 58.9% while, the second group was responsible for 24.5% of the total variability. Cluster analysis reflected the tendency of each group of variables in one cluster to relate closely to each other. Analysis of six statistical procedures revealed that high yield of cotton can possibly be obtained by selecting breeding materials that have high seed yield per plot (x7) and high yield per plot (x6), but have low number of dry polls per plant (x2). © 2014 PSCI Publisher All rights reserved.

Cotton acreage in the Coastal Plain of the Southeast has increased in recent years. The soils in this region are sandy and typically have a low retention capacity for sulfate S. A 3-yr (1993-1995) field test was conducted in south Alabama on a Lucy loamy sand (loamy, kaolinitic, thermic Arenic Kandiudults) to evaluate the response of cotton (Gossypium hirsutum L.) to the source, rate, and timing of S fertilizer applications. Sulfur was broadcast preplant as either ammonium sulfate, elemental S, potassium sulfate, potassium thiosulfate, or K-Mg-sulfate at rates of 0, 10, 20 and 40 lb S/acre. Additionally, ammonium sulfate was applied at first square to evaluate timing effects. Lint yields were increased each year and they peaked at a rate of approximately 20 lb S/acre on this Lucy Is soil. Averaged across sources, 20 lb S/acre increased lint yields by an average of 21% as compared with the no S check treatment. Lint yields were not affected by time of S application in 1993 or 1995, but a preplant application of S increased yield compared with S applied at first square in 1994. The response to time of S application was attributed to heavy rainfall that was received soon after the first square application of S. Sources of S did not affect lint yield in 1993 or 1995, but ammonium sulfate and K-Mg-sulfate produced slightly higher yields than those of other sources in 1994, an extremely wet growing season. Lint quality, as measured by high volume instrumentation (HVI), was not affected by any S treatment in 1993 or 1994. In 1995, fiber length increased with S rate, but the differences among sources were inconsistent. Results of this test suggest that cotton produced on sandy Coastal Plain soils that are low in S may require annual applications of 20 lb S/acre to ensure high yields. The S should be applied preplant, although delaying application to first square should not limit yields. For lint production, differences among commercial S fertilizer sources should be minimal.

Field experiments were conducted to evaluate the effect of soil-incorporated poultry litter on the population dynamics of Hoplolaimus columbus and cotton lint yield. Rates of poultry litter applied varied from 0.0 to 27.0 t/ha and were applied in December, February, or March. Time of application did not influence population densities of this nematode or cotton yield. The rate of poultry litter applied was negatively related to the population density of H. columbus at midseason, but not at other sampling dates. The lower midseason levels of this nematode corresponded with increases in cotton lint yield in all experiments. Cotton yield increases generally were linear with respect to the rate of litter applied, although the highest rates of litter applied did not always result in the greatest cotton yield. Poultry litter can be used effectively to supply nutrients to the crop and suppress damaging levels of H. columbus. Optimal rates of litter application were from 6.0 to 13.4 t/ha. Application of poultry litter at these rates, however, may exceed nutrient levels required for best management practices.

Retention of cotton stubble enhances N fertilizer recovery and lint yield of irrigated cotton

This investigation was carried out at Sakha Experimental Station, Agricultural Research Center during four seasons 2013, 2014, 2015 and 2016. Five populations (P1, P2, F1, F2 and F3) for the four barbadense cotton crosses namely (Uzbekstan1 x C.B 58), (TNB x C.B 58), (BBB x C.B 58) and (Giza 94 x Giza 45) were used in this investigation to study the genetic behaviour of yield and its components and fibre traits. The aim of the present investigation was to study heterosis, inbreeding depression and type of gene action in four intra-specific crosses to obtain additional information about some genetic parameters to help the breeder to select effective breeding methods. The results showed that the potence ratio estimates indicated overdominance for seed cotton and lint yield/plant, boll weight, lint percentage and number of bolls/plant, while the quality traits exhibited partial dominance. Highly significant positive heterotic effects relative to mid-parent and better parent were obtained for seed cotton yield, lint cotton yield and number of bolls/plant, while it was for lint percentage. The inbreeding depression effects were highly significant for the number of bolls/plant, seed cotton yield and lint cotton yield. Highly significant values of additive and dominance were found for seed cotton yield, lint cotton yield and number of bolls/plant. Dominance effects for Micronaire value and fibre length were of greater magnitude than additive effects. Highly significant epistasis values were found for additive x additive and dominance x dominance with complementary action with non-additive effect. High broad-sense heritability values were calculated for all studied traits, while narrow sense heritability values were of low values for seed cotton and lint cotton yield. on the other hand the fibre quality traits exhibited high values in three crosses as well as the heritabilities of regression

The development of conservation tillage systems for cotton (Gossypium hirsutumL.), capable of reducing soil erosion and improving soil quality while increasing yields and profits, remains a challenge in the southeastern USA. Poor emergence and growth, delayed maturity, and reduced yield are some of the problems that have been encountered in the use of conservation tillage on cotton. The objectives of this study was to evaluate the effects of tillage (no‐till, mulch‐till, conventional till), cropping system [cotton–winter fallow, cotton–winter rye (Secale cerealeL.) cover crop] and N source (poultry litter, ammonium nitrate) on growth and yield of cotton from 1996 to 1998 in northern Alabama. In 1997, cotton lint yield under no‐till (NT) was 24 and 18% greater than that under conventional till (CT) and mulch‐till (MT) systems, respectively. In 1998, cotton lint yield under the NT system was 7% greater than that under CT. Poultry litter (PL) at 100 kg N ha−1gave similar lint yield to ammonium nitrate (AN), whereas at 200 kg N ha−1, lint yields were significantly greater. No‐till, cotton–winter rye cropping, and surface application of 200 kg N ha−1in form of PL conserved soil moisture in the top 7 cm of the soil. This resulted in early seedling emergence, high seedling vigor, good plant growth, and high lint yield of cotton. These treatments would be appropriate for use in the southeastern USA where soil erosion is a problem and plenty of PL is available each year from the poultry industry.

A field experiment was conducted at the research farm of Kunduz Spinzar State-Owned Corporation in Collaboration with Kunduz University to evaluate response of cotton varieties to phosphorus fertilizer on growth, yield and economic efficiency in northeast of Afghanistan, the experimental design was Randomized Complete Block Design (RCBD) With split arrangement each replicated thrice, The study involved three cotton varieties (CD-401, AND-123 and K-01) and four phosphorus fertilizer levels (control, 30 kg p2o5/ha, 60 kg p2o5/ha and 90 kg p2o5/ha), different cotton varieties and phosphorus have significant impact on yield and economic parameters, the maximum Lint Cotton yield (1,749.02 kg/ha), Seed Cotton yield (3,666.07 kg/ha), Lint Cotton Yield (187,390AFN/ha), Seed Cotton yield (167,539 AFN/ha), gross return (354,929 AFN/ha), net return (339,876 AFN/ha) and B: Cost ratio (7.67) was in AND-123 variety compared with CD-401 and K-01 varieties respectively. The highest Lint Cotton yield (1,627.50 kg/ha), Seed Cotton yield (3,110.38 kg/ha), Lint Cotton Yield (174,370AFN/ha), Seed Cotton yield (142,144 AFN/ha), gross return (316,515 AFN/ha), net return (297,790 AFN/ha) and B: Cost ratio (7.67) was in 90 kg P2O5 kg ha-1 followed by phosphorus application of 60 kg P2O5 kg ha-1, 30 kg P2O5 kg ha-1 and control respectively. It can be concluded AND-123 cotton variety along with 90 kg p2o5/ha is the best combination for cotton productivity and profitability in northeast of Afghanistan.

Comparative studies for thirty eight genotypes descending from twenty one crosses and the two check varieties Giza 90 and Giza 80 were included in Trial A at Seds Agricultural Experimental Station in 2012 season, eighteen genotypes descending from sixteen crosses and the two check varieties Giza 90 and Giza 80 were grown in Trial B at five locations in Middle and Upper Egypt in the same season. The results obtained from Trial A showed that the strains H5118/2011 and H5124/2011 of the cross (G 83 Rad. x Aust.) x G 91, H5128/2011 and H5129/2011 cross [(G 80 x Aust) x G 83], H5150/2011 cross (G 83rad x Kar) x [(G 83 x G 80) x G 89], H6198/2011 cross[[(G 83 x G 80) x G 89] x (G 83 x Delta Pine)]], H7215/2011 cross [(G 83 x G 80) x G 89] x Aust, H8238/2011 cross (Dand. Rad x Karsh), H9244/2011cross [G 90 x Pima S62 (24240)], H9253/2011 cross [G 91 x Pima S62 (24240)], H10268/2011 [G 83 x (G 72 x Dand.) x G 91], H11281/2011[G 83 x (G 72 x Dand.) x G 85] and Breeder1 of the promising cross [G 83 x (G 72 x 5844)] x G 80] recorded significant higher seed cotton yield (SCY) and lint cotton yield (LY) compared with the check varieties Giza 90 and Giza 80. While the crosses [(G 85 x G 83) x G 90], [(G 83 x G 80) x G 89] x Aust, C.B 58 x G 90, H8249/2010 descending from the crosses G 91 x Pima S62 (24202), [G 83 x (G 75 x 5844) x G 91], [(G 83 x G 72) x Dand] x G 85 respectively and breeder2 of the promising cross (Giza90 x Aus) had higher seed and lint cotton yield (SCY and LY) compared with the check varities Giza 90 and Giza 80 in Trial B. The mean squares of the genotypes in Trial A were highly significant for all yield components traits. Combined mean squares results in Trial B of the genotypes (G) were highly significant and significant for all yield traits except for lint index (LI). Environments (E) mean squares were highly significant for all studied yield traits. Genotypes-environments interactions (G x E) mean squares were highly significant for all yield traits except for lint percentage (L%) which showed significant combined mean squares, indicating change in performance of genotypes from one location to another. In other words, the rank of a genotype differed from one location to another. High heritability estimates in broad sense (h.b.s %) were computed for all yield traits in Trial A, indicated that the environment had slightly influence on these traits. Broad sense heritability estimates (h.b.s %) for yield traits in Trial B were low for seed cotton yield (SCY), lint yield (LY) and boll weight (BW), indicated that the environmental factors had effect on these traits. On the other hand, lint percentage (L %), seed index (SI) and lint index (LI) recorded high heritability estimates in broad sense (h.b.s %) (more than 50%), indicating that environment had considerable effect on these traits.. The G.C.V % values ranged from 2.54% for lint index (LI) to 61.65% for lint yield (LY) in Trial A and ranged from 3.98% for lint percentage (L %) to 50.0% for lint yield (LY) in Trial B. These values indicated variable environmental effects on all studied traits.

Subsurface band application of broiler litter in soil is being evaluated across the United States as a potential management practice for curbing phosphorus loss and improving nutrient retention. This management practice also shows promise for increasing yields of row crop systems. Determining the optimum plant distance from the subsurface banded broiler litter (BL) could be useful to optimize crop yields. Thus, a cotton (Gossypium hirsutum L.) experiment was established to investigate the distance of a subsurface BL band from the planted row on cotton growth and yield. Treatments consisted of subsurface banding BL at 0, 10, 20, 30 cm from the crop row plus a non‐fertilized check, broadcast BL, and banding of urea‐ammonium nitrate (UAN) at 20 cm to the side of rows as controls. Subsurface band placement of BL and UAN occurred just prior to sowing at a depth of 10 cm. Placing BL in subsurface bands tended to increase cotton yield compared to surface broadcasting the litter. When comparing BL band positions, cotton lint yield was generally greatest when BL was placed in subsurface bands 20 cm or less from the planted row. Minimal differences in cotton fiber quality were observed among treatments. Results suggest the reduced distance between the cotton row and a subsurface BL band can increase cotton growth and yield.

The United States is experiencing longer crop growing season in most states, which could afford producers the opportunity to diversify into double‐cropping (DC) and cover crop systems rather than the predominant summer and winter fallow systems. Thus, this study evaluated DC and cover crops effects on wheat (Triticum aestivum L.), cotton (Gossypium hirsutum L.), and soybean (Glycine max) yield under conventional tillage (CT) and no‐tillage (NT). Summer cover crops (SCCs) were sunn hemp (Crotolaria juncea L.) and sorghum sudangrass (Sorghum bicolor), while winter cover crops (WCCs) were Austrian winter pea (Pisum sativum) and wheat. Cropping systems were wheat‐fallow (W‐F), wheat‐cotton (W‐C), wheat‐soybean (W‐S), W‐SCC, WCC‐C, F‐C, WCC‐S, and F‐S. Tillage effect on crop yields varied across years. In 2021, wheat yield in CT of W‐C, W‐F, and W‐SCC (2831, 2689, and 2646 kg ha−1) significantly differed from NT of W‐S (1720 kg ha−1). No significant tillage effect was observed on cotton lint yield between W‐C and WCC‐C. For soybean, in 2020, the CT of W‐S and WCC‐S significantly outyielded the NT of W‐S and WCC‐S. Cropping system effect on wheat yield between W‐S and W‐SCC (1419 and 1987 kg ha−1) was significant in 2020 due to low stand counts in W‐SCC arising from the thick SCC biomass. Cotton lint yield in WCC‐C outyielded W‐C in all 3 years but was not significant. Soybean grain yield in W‐S was consistently higher than in WCC‐S, though not significant. Cotton lint and soybean grain yield in the fallow systems were the least. Overall, in a short term, crop yield in DC and cover crop systems were similar.

Predicting and interpreting cotton yield and its determinants under long-term conservation management practices using machine learning

Field experiments were conducted in Hale Co., TX, in 2005 and 2006 to determine the effects of 2,4-D amine and dicamba applied at varying rates and growth stages on cotton growth and yield, and to correlate cotton injury levels and lint yield reductions. Dicamba or 2,4-D amine was applied at four growth stages including cotyledon to two-leaf, four- to five-leaf, pinhead square, and early bloom. Dicamba and 2,4-D amine were applied at 1/2, 1/20, 1/200, and 1/2000 of the recommended use rate. Crop injury was recorded at 14 days after treatments and late-season, and cotton lint yields were determined. Across all growth stages, 2,4-D caused more crop injury and yield loss than dicamba. Cotton lint was reduced more by later applications (especially pinhead square) and injury underestimated yield loss with 2,4-D. Visual estimates of injury overestimated yield loss when 2,4-D or dicamba was applied early (cotyledon to two leaf) and was not a good predictor of yield loss.

از مؤلفه های مهم کشاورزی پایدار در مناطق خشک و نیمه خشک، مقدار آب و شوری آب و خاک است که از عوامل مهم کاهش کیفیت خاک، محسوب می‌شوند. مواد آلی شاخصی از کیفیت خاک است، اما از آنجا که به تغییرات مدیریت خاک به کندی پاسخ می دهد، مطالعه اجزاء حساستر آن ممکن است باعث تشخیص بهتر نقش تغییر مدیریت بر کیفیت خاک گردد. از این رو تحقیق حاضر با هدف بررسی کیفیت خاک با استفاده از شاخصهای کربن ناپایدار و مدیریت کربن خاک در تعدادی از اراضی کشاورزی نیریز در استان فارس انجام گردید. برای این منظور پنج مزرعه از مزارع گندم و جو آبی در حومه شهر نیریز که مقدار و شوری آب آبیاری متفاوت داشتند، انتخاب گردیدند. در هر مزرعه، سه نقطه انتخاب و نمونه‌های خاک از عمق 40-0 سانتیمتر و نمونه‌های گیاه در مربعهای 1×1 متر، تهیه شد. نمونه آب نیز، از چاه آبیاری برداشت گردید. ویژگیهای فیزیکی و شیمیایی خاک و آب اندازه گیری و مقدارکربن ناپایدار و شاخص مدیریت کربن خاک محاسبه گردید. نتایج نشان داد کربن ناپایدار خاک نسبت به کربن آلی کل، حساسیت بیشتری به مدیریت زراعی دارد و حتی در مزارع با مدیریت زراعی یکسان و عملکرد مشابه، مقدار و یا شوری متفاوت آب آبیاری می تواند باعث تغییر در کربن ناپایدار خاک و در نتیجه کیفیت خاک گردد. براساس نتایج، مقدار بالاتر شاخص مدیریت کربن لزوما با عملکرد بالاتر محصول ارتباط ندارد و ممکن است با ویژگیهای کیفی محصول ارتباط داشته باشد که نیاز به تحقیق بیشتر دارد.