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The objective of this work was to evaluate the effect of different planting dates on the morphological variables and yield of new potato cultivars. The treatments were three cultivars (Agata, BRS Clara and BRS F63 Camila) and three planting date (October, December and February), carried out in two crop years (2014/15 and 2015/16). Total and marketable yields, average mass of total and marketable tubers, growth period, leaf area index, number and dry weight of the tubers were evaluated. The first planting date resulted in higher yield than the third date. Cultivar BRS F63 Camila was the one with highest yield in this first planting date (47.4 t ha-1), due to greater number of tubers produced in relation to the other cultivars and to higher average tuber weight (166 g tuber-1) in relation to Agata (113 g tuber-1). In the second planting date, no difference in yield was observed among cultivars. In the third planting date, BRS Clara was the cultivar with highest yield (21.3 t ha-1), due mainly to higher average weight of tubers (105 g tuber-1) in relation to Agata (49 g tuber-1), a fact favored by the higher leaf area index and longer growth period of BRS Clara. Depending on the planting date, one should choose the cultivar that results in maximum yield potential, since it is a plant management with low cost and high yield impact. For the second planting date, any of the studied cultivars can be used. RESUMO O objetivo deste trabalho foi avaliar o efeito de diferentes épocas de plantio nas variáveis morfológicas e na produtividade de novas cultivares de batata. Os tratamentos foram três cultivares (Ágata, BRS Clara e BRS F63 Camila) e três épocas de plantio (outubro, dezembro e fevereiro), realizados em duas safras agrícolas (2014/15 e 2015/16). Avaliou-se a produtividade total e comercial, a massa média de tubérculo total e comercial, o período de crescimento das plantas, o índice de área foliar, o número e a massa seca dos tubérculos. A primeira época de plantio resultou em maior produtividade que a terceira época. A cultivar BRS F63 Camila foi aquela com maior produtividade nessa primeira época de plantio (47,4 t ha-1), devido ao maior número de tubérculos produzidos em relação às demais cultivares e ao maior peso médio de tubérculos (166 g tubérculo-1) em relação à Ágata (113 g tubérculo-1). Na segunda época de plantio, não houve diferença na produtividade entre as cultivares. Na terceira época de plantio, a cultivar BRS Clara apresentou a maior produtividade (21,3 t ha-1), devido principalmente ao maior peso médio dos tubérculos (105 g tubérculo-1) em relação à Ágata (49 g tubérculo-1), fato favorecido pelo maior índice de área foliar e maior período de crescimento da cultivar BRS Clara. Dependendo da época de plantio, deve-se escolher a cultivar que resulte em máximo potencial produtivo, já que é um manejo das plantas com baixo custo e alto impacto na produtividade. Para a segunda data de plantio, qualquer uma das cultivares estudadas pode ser utilizada.

Intermediate wheatgrass (IWG) is a new perennial dual-use crop for grain and forage with growing interest among farmers. Intercropping IWG with red clover may increase yield and nutritive value through nitrogen transfer. IWG and red clover planting timing can affect grain and forage yield, and there has not been previous research on this management practice. At two locations (Arlington and Lancaster, WI, USA) a factorial experiment was established two years with two factors: (1) IWG planting date (August through October, and April) and (2) red clover planting season (in the fall with IWG or frost seeded in the next spring). Yield data were collected for two subsequent years. Grain yield was maximized at 515 kg ha−1 and 423 kg ha−1 at Arlington and Lancaster when planted by 26 August and 13 September, respectively. Planting date influenced grain yields in the first harvest year but not in the second. Seeding red clover in the spring increased IWG and red clover biomass compared to seeding it in the fall. In Wisconsin, planting IWG by early September at the latest and planting red clover in the spring is recommended to maximize grain yield.

Forage brassicas are used as a forage in monoculture and multispecies mixtures, yet research defining best management practices is limited. Two studies were conducted to evaluate the effects of land preparation method and planting date on establishment, forage mass, and quality of two Brassica species, ‘Inspiration’ canola (Brassica napus L.) and ‘T-Raptor’ hybrid turnip (B. rapa subsp. rapa × B. rapa L.). Each experiment was a randomized complete block design evaluating four land preparation methods: (conventional till (CT), no-till after burning (NB), no-till after mowing (NM), and no-till without residue removal (NR)), and four planting dates: (1 September (S1), 15 September (S15), 1 October (O1), and 15 October (O15)). Significant differences were observed for the canola seedling emergence, but are not of biological significance. Hybrid turnip seedling emergence was the greatest for the CT treatment and consistently greater than NM and NR treatments. Forage mass in the canola study was greatest for the CT and NB. Hybrid turnip forage mass demonstrated similar trends to the canola. CT had the greatest mass and the NR and NM treatments tended to provide the lowest forage mass. Across both studies, earlier planting dates (S1 and S15) resulted in greater overall forage mass than the later planting dates (O1 and O15). Forage nutritive value overall was lower in earlier planted brassica, however, forage nutritive value was not reduced enough to negatively impact livestock.

A 2-year farm trial by employing the nutrient priming technique on common bean (Sar?k?z) and cowpea (?imal) seeds was performed to assess seed yield and protein content. Priming: (p1) control, (p2) KH2PO4, (p3) ZnSO4 and (p4) KH2PO4+ZnSO4, planting date: (d1) 20 May, (d2) 15 June 2015, (d1) 7 May, (d2) 7 June 2016 were used to study the yield (kg ha-1) and crude protein (%) of the mentioned crops in Ankara, Turkey. In 2015, application of p3 and p4 (868.8, 834.8), d2 (962.3) and p4d2, p2d2 and p3d2 (1061, 1052, 1028) increased seed yield of Sar?k?z, and p2 and p1 (899.5, 835.9) and d2 (955.9) increased the yield of ?imal. Treatments of p4 and p3 (18.7, 18.5), d2 (19.2), and p4d2 (21.3) increased the protein of Sar?k?z and d2 (19.4) increased the protein of ?imal. In 2016, p3 (2506), d2 (2516) and p3d2 (3650) increased the yield, and p4 (26.1), d2 (26.8) and p4d2 (28.3) increased the protein of Sar?k?z. Treatments of p3 (1979.1), d2 (2664.3) and p3d2 (3310.6) increased the yield, and d1 (24.1) and p3d1 (25.7) increased the protein of ?imal. Application of Zn and P by seed priming seems to effectively increase the yield and protein content of these crops.

Planting date plays important role in the growth, development and yield of maize. Optimum planting date has becomes a prime importance for higher crop production. The plant establishment as well as pest and disease incidence are affected by planting dates. Crop varieties respond differently to planting dates. Early or late planting dates on maize causes an array of morpho-anatomical, physiological and biochemical changes in plants, which affect plant growth and development and such changes may lead to a drastic reduction in yield. Maize growth and development involves numerous biochemical reactions which are sensitive to variance in weather parameters as affected by planting dates. Delayed planting dates affect traits namely anthesis silking interval, photosynthesis, physiological maturity and dry matter production due to reduction in cumulative interception of photosynthetically active radiation (PAR). Late planting dates cause higher non-structural carbohydrate concentration in stems at mid-grain filling stages due to low temperature exposure of crop limiting kernel growth and photosynthesis. The adverse effects of delayed planting dates can be mitigated by forecasting optimum planting dates through crop modeling experiments. This article summarizes various effects of planting dates on maize growth, development and yield parameters. This information may be useful for maize growers and researchers.

There is an increasing market for locally grown malting barley (Hordeum vulgare L.) in the Northeast US. Malting barley must meet certain quality standards for acceptability in the brewing market. Up-to-date recommendations are needed regionally for adaptation to ongoing climate change. A two-year field experiment was conducted to assess the interactive influence of three dates of planting (5 September, 15 September, and 25 September), two levels of fall N (0 or 28 kg ha−1), and three levels of spring N (28, 50.5, and 73 kg ha−1). No significant difference was detected in grain yield amongst the treatments. The date of planting and fall N application mainly affected crop growth while spring N impacted grain quality. Delayed planting led to better winter survival and reduced lodging and foliar disease. Fall N application reduced winter survival for the early September planting but had minimal other agronomic impacts. An increased spring N application rate increased grain protein and lowered falling number, but there were no treatment differences in other quality parameters. Results indicated that late September planting, application of no fall N, and moderate spring N (28 kg ha−1) resulted in the highest agronomic N efficiency and grain quality for malting barley in Northeast.

The objective of this study was to develop a climate risk zoning for damage to gladiolus due to low and high temperature under climate change scenarios projected by the end of the century in the Rio Grande do Sul State, Brazil. The PhenoGlad model was used in this study to determine the recommended periods for planting gladiolus throughout the year across the Rio Grande do Sul State. The model was run for daily planting dates (from 01 January to 31 December), for different gladiolus developmental cycles (Early, Intermediate I, Intermediate II and Late). The climate change scenarios were from CMIP5: RCP2.6, RCP4.5 and RCP8.5, representing optimistic, intermediate and pessimistic scenarios of greenhouse gases emission, respectively. Planting dates were considered recommended when crop damage, due to high or low temperatures, occurred in less than 10% of the years. Warmer regions like Uruguaiana and Iraí have the shortest recommended time for planting throughout the year in the three climate change scenarios. Plantings between August and December are predicted to be the most affected and are not recommended because of the higher chance of damage from high temperatures. Colder regions like Bom Jesus will be favored in climate change scenarios since there will be an extended recommended period for planting in the seasons of the year that currently suffer damage by low temperatures. To meet demands of gladiolus during the hottest period of the year, it will be necessary to develop techniques to reduce damage from high temperatures in the crop, such as more tolerant cultivars or the use of shading screens on the crop. RESUMO Objetivou-se neste estudo desenvolver um zoneamento de risco climático para a cultura do gladíolo nos cenários de mudança climática previstos para o final do século no Rio Grande do Sul, considerando a ocorrência de danos causados por altas e baixas temperaturas. O modelo PhenoGlad foi utilizado neste estudo para determinar os períodos recomendados para plantio ao longo do ano em todo o Rio Grande do Sul. O modelo foi rodado para datas de plantio diários (de 01 janeiro a 31 dezembro), para diferentes ciclos de desenvolvimento da cultura (Precoce, Intermediário I, Intermediário II e Tardio). Os cenários de mudança climática utilizados foram do CMIP5: RCP2.6, RCP4.5 e RCP8.5, representing optimist, intermediate and pessimist scenarios of greenhouse gases emission, respectively. As datas de plantio foram consideradas recomendadas quando danos na cultura por altas ou baixas temperaturas ocorreram em menos de 10% dos anos avaliados. Regiões mais quentes como Uruguaiana e Iraí apresentam o menor período recomendado para plantio ao longo do ano nos três cenários climáticos. Plantios entre agosto e dezembro não são recomendados devido a maior chance de danos por altas temperaturas. Regiões mais frias como Bom Jesus serão favorecidas nos cenários de mudança climática, pois haverá uma ampliação do período recomendado para plantio nas épocas do ano que atualmente sofrem danos por baixas temperaturas. Para atender à demanda de gladíolo durante os períodos mais quentes do ano, será necessário desenvolver técnicas para reduzir os danos por altas temperaturas na cultura, como cultivares mais tolerantes ou o uso de telas de sombreamento sobre a cultura.

Edamame is a food-grade soybean [Glycine max (L.) Merr.] that is harvested immature between the R6 and R7 reproductive stages. To be labeled as a premium product, the edamame market demands large pod size and intense green color. A staggered harvest season is critical for the commercial industry to post-harvest process the crop in a timely manner. Currently, there is little information to assist in predicting the optimum time to harvest edamame when the pods are at their collective largest size and greenest color. The objectives of this study were to assess the impact of cultivar, planting date, and harvest date on edamame color, pod weight, and a newly minted Edamame Harvest Quality Index combining both aforementioned factors. And to predict edamame harvest quality based on phenological stages, thermal units, and planting dates. We observed that pod color and weight depended on the cultivar, planting date, and harvest date combination. Our results also indicated that edamame quality is increased with delayed planting dates and that quality was dependent on harvest date with a quadratic negative response to delaying harvest. Maximum quality depended on cultivar and planting and harvest dates, but it remained stable for an interval of 18–27 days around the peak. Finally, we observed that the number of days between R1 and harvest was consistently identified as a key factor driving edamame quality by both stepwise regression and neural network analysis. These research results will help define a planting and harvest strategy for edamame production in Arkansas and the United States Mid-South.

As resistance to herbicides limits growers' weed management options, integrated weed management (IWM) systems that combine non-chemical tactics with herbicides are becoming critical. A 2 year integrated weed management (IWM) study was conducted at three locations in VA, USA. The factorial study evaluated: (1) soybean planting date (early or late planted) (2) with or without winter cover (cereal rye/wheat or no cover), and (3) with or without harvest weed seed control (HWSC). Prior to soybean planting in the first year, winter cover resulted in a 22% reduction in common ragweed density compared to no cover. At soybean harvest in the first year, the lowest common ragweed densities were in the late planted plots following winter wheat, and common ragweed aboveground biomass was reduced by 46 and 22% at two locations in late planted compared to early planted soybean. To evaluate the impact of the first year's treatments and HWSC, full season soybeans were planted across the trial in the second year. Prior to soybean planting in the second year, late planting in the first year common ragweed density was reduced by 83% at one location, but significant reductions were not observed elsewhere. When comparing winter cover to no cover, common ragweed densities were reduced by 31 and 49% at two locations and densities were similar at the third location. Harvest weed seed control reduced common ragweed density by 43% at one location compared to the conventional harvest plots but no significant reductions were observed at the other locations or at other rating timings. However, there was a significant location by planting date by winter cover interaction and the overall lowest common ragweed densities (4.1 to 10.3 plants m−2) were in the late planted plots with winter cover. This research indicated that winter cover, late planting, and HWSC can reduce common ragweed populations with late planting being the most influential. Therefore, double-cropping soybean after wheat is likely the most viable means to better control common ragweed using IWM as it combines both winter cover and late planting date.

Gladiola ( Gladiolus × grandiflorus Hort.) is an important cut flower for small farmers in Brazil. While the El Niño Southern Oscillation, which causes interannual variability to air temperature in Southern Brazil, can shift the optimum planting window of gladiola, an increase in temperature due to climate change can accelerate gladiola flowering and cause injuries by heat. The objective of this study was to assess the potential climate change effects on gladiola optimum planting date for specific market dates and investigate injuries occurrence on spikes in the Rio Grande do Sul State, Brazil. Field experiments were conducted from 2016 to 2018 at four different locations across the Rio Grande do Sul State to evaluate the performance of the PhenoGlad model in simulating the developmental stages of gladiola. The PhenoGlad model was run on climate scenarios of the Coupled Model Intercomparison Project Phase 5 (CMIP5) named RCP2.6, RCP4.5 and RCP8.5 scenarios. The climate change scenarios caused a delay in the optimum planting date to harvest gladiola for All Souls’ Day across the Rio Grande do Sul State. For harvesting spikes for Mother’s Day, negative anomalies (earliest planting date) occurred in the warmest regions, because the very high temperature extended the crop development. Injuries by heat on spikes reached positive anomalies in 70 % of the years in the warmest regions for scenario RCP8.5. To harvest spikes for Mother’s Day, heat injury did not exceed 20 % of the years. Mitigation strategies for farmers to deal with climate change and keep their gladiola production include adjusting the optimum planting date.

The study parameterised and validated performance of AquaCrop model, to simulate attainable yields for chickpea crop in response to the effects of planting date in the Northestern Region of South Africa. Model calibration data were obtained from two field experiments of contrasting water regime, planted in 2014 winter season at University of Venda, South Africa, whilst data for model validation was obtained from 2015 planting season from the same station. The model performance was satisfactory, with a good combination between the simulated and observed canopy cover (CC), Soil water content (SWC), biomass (B) and grain yield (Y). All the statistical indicators (R2, RMSE, and MAPE) used to compare field observed and model-predicted parameters, showed good performance. For example, the regression analysis of simulated and observed yield showed a good relationship with R2 values of 0.949, 0.928 and 0.990 for early, normal and late planting dates, respectively, whilst RMSE was 0.135, 0.143 and 0.031 for early, normal and late planting dates. Similarly, SWC had strong regression relationship (R2 = 0.982, 0.949, 0.954, respectively, and a RMSE of 0.226, 0.696 and 0.310, respectively, in early, normal and late planting date). The results indicate that the model could be used for evaluating the effects of different planting dates on chickpea yield.

Constraints are reported for the low productivity and quality of onion seed production in Ethiopia. Therefore, a field experiment was conducted at Kobo sub-center research station and Libso investment farm to study the influence of planting date and onion bulb size on yield and quality of onion seed. The experiment was laid out in Randomized Complete Block Design with three replications and involved three levels of onion bulb sizes and four levels of planting dates. The results of the study revealed that significant interactions between planting date and mother bulb size on seed yield ton ha-1, germination percentage, seed vigor index I and seed vigor index II. The highest seed yield (2.8 tons ha−1) was recorded from large onion bulbs of a size planted at Kobo early—October. Planted onion bulbs early-October increased seed yield (ton ha−1 by 21.7%) than planted early-November. Regarding onion bulb size, large bulbs increased seed yield (ton ha−1 by 40%) than the small bulbs. The highest (97.3) germination percentage was recorded from large onion bulbs planted at Kobo in early-October. Therefore, for the production of better yield and quality of onion seeds, early-October planting and large onion bulbs (4.1–5 cm) can be recommended in the study areas and other similar agro-ecology areas of the country.

Growth and photosynthesis performance of cassava during early vegetative growth are important determinants of final biomass. The objective of this work was to investigate canopy structure and photosynthesis performance of four cassava genotypes (Rayong 9, Rayong 11, Kasetsart 50, and CMR38-125-77) growing under irrigation at 3 and 6 months after planting (3MAP and 6MAP). Data for the 3MAP plants were collected from cassava planted on 30 June (Rainy PD), 10 November (Cool PD1), and 15 December (Cool PD2) 2015, and for the 6MAP from those planted on 20 April 2015 (Hot PD), Rainy PD, and Cool PD1. The plants growing in the rainy season had significantly higher leaf area index (LAI) than those growing in the cool and hot seasons. Consequently, they had lower percentage light penetration at the bottom of canopy, and therefore more light interception through the canopy, and hence a higher mean net photosynthesis rate (Pn) across the six canopy levels. At the 3MAP, which is the stage of maximum rate of leaf and stem growth, the Rainy PD and Cool PD2 plants of CMR38-125-77 showed the highest LAI and highest mean Pn. Similarly, the Cool PD1 plants of Kasetsart 50 showed the highest LAI and highest mean Pn. In contrast, at 6MAP during the stage of active starch accumulation in storage roots, the genotypes with the highest mean Pn were the ones having an intermediate (CMR38-125-77 for the Hot PD) or low LAI (Rayong 9 for the Rainy PD, and CMR38-125-77 for the Cool PD1). Data on variations in canopy structure and photosynthesis potentials of different cassava genotypes in response to seasonal variations may be useful for crop growth modeling and may be employed as a criterion for the selection of suitable genotypes for each growing season.

Andean lupin in Europe has regained interest in recent years due to its high seed protein and oil content and its potential use for food, feed as well as a crop used in biorefineries. A search for suitable germplasm in combination with a determination of appropriate agronomical practices such as planting date are needed for commercial farming in new areas. The current study aims to evaluate the performance of six selected L. mutabilis accessions in a Mediterranean area using two different planting dates for two consecutive experimental years. A split plot design with accessions as subplots and planting dates as main plots was used. Measurements such as days to flowering, plant height, total number of pods and seeds per plant, seed yield and seed crude protein content were taken. All accessions performed better when cultivation started not later than the end of autumn since high temperatures occurred during late spring shortened the growth cycle and reduced yield. Earlier cultivation applied, in the middle of autumn, did not enhance significantly seed yield production. Among the accessions, LIB223 was characterized by the highest seed crude protein content in the early planting treatment, while accessions with prolonged growth cycle (LIB209, LIB214 and LIB223) produced higher seed yield than other accessions and could be further studied as promising breeding material for cultivation under the edaphoclimatic conditions tested.

Since water is increasingly becoming an expensive and limited resource, it is necessary to improve crop water use efficiency (WUE) to save water while maintaining high yields. The objective of this research was to evaluate the effects of moderate water stress compared to well-watered conditions (supplying 50 or 100% of the maximum evapotranspiration (ETm)) on dry aboveground biomass yield (AB-Y), dry whole biomass yield (WB), tuber yield, irrigation WUE, and WUE at early harvest (E-TY, E-IWUE, E-YWUE), and at final harvest (F-TY, F-IWUE, F-YWUE), on WUE for dry aboveground biomass (AB-WUE) and for dry whole biomass (WB-WUE), on sink/source ratio and dry matter content of tubers in two potato cultivars&mdash, Sieglinde and Spunta, in two planting dates (early and late). Moderate water stress, compared to well-watered conditions, resulted in a small decrease in E-TY (&minus, 14%) and F-TY (&minus, 11%), but a high increase in E-IWUE (+69%) and F-IWUE (+78%), making savings in irrigation water of roughly 380 or 600 m3 per crop cycle in relation to early or final harvest. Moderate water stress improved in Sieglinde IWUE, YWUE, and WB-WUE at final harvest, whereas Spunta appeared more appropriate for early harvest. In the late planting date, the crop used water better compared to the early planting, resulting in a greater increase in IWUE (+77 vs. +66%) and an, albeit, slight increase in the WUE. It would, therefore, be convenient to apply the moderate water stress in the late planting, saving a further 100 m3 of irrigation water. The highest yield, IWUE, and YWUE were reached when moderate water stress was applied in both planting dates on cv. Spunta for early harvest and on cv. Sieglinde for final harvest. It was possible to increase WUE indices and save water, not only by water management, but also by choosing opportune planting dates and cultivars.

Wheat plays a very important role in China&rsquo, s agriculture. The wheat grain yields are affected by the growing period that is determined by temperature, precipitation, and field management, such as planting date and cultivar species. Here, we used the CSM-CERES-Wheat model along with different Representative Concentration Pathways (RCPs) and two global circulation models (GCMs) to simulate different impacts on the winter wheat that caused by changing climate for 2025 and 2050 projections for Guanzhong Plain in Northwest China. Our results showed that it is obvious that there is a warming trend in Guanzhong Plain, the mean temperature for the different scenarios increased up to 3.8 &deg, C. Furthermore, the precipitation varied in the year, in general, the rainfall in February and August was increased, while it decreased in April, October and November. However, the solar radiation was found to be greatly reduced in the Guanzhong Plain. Compared to the reference year, the results showed that the number of days to maturity was shortened 3&ndash, 24 days, and the main reason was the increased temperature during the winter wheat growing period. Moreover, five planting dates (from October 7 to 27 with five days per step) were applied to simulate the final yield and to select an appropriate planting date for the study area. The yield changed smallest based on Geophysical Fluid Dynamics Laboratory (GFDL)-CM3 (&minus, 6.5, &minus, 5.3, &minus, 4.2 based on RCP 4.5, RCP 6.0, and RCP 8.5) for 2025 when planting on October 27. Farmers might have to plant the crop before October 27.

The objective of this study was to determine the cycle duration in days and the quantitative parameters, i.e. stem length, spike length and stem diameter of gladiolus floral stems as a function of the planting date and locations in the Rio Grande do Sul/Brazil. Field experiments were established between 2014-2015 in three locations (Frederico Westphalen, Itaqui and Santa Maria). The experimental design was a complete randomized block, with six gladiolus cultivars in three distinct planting dates at each location as treatments. The shift from vegetative to reproductive stage, the stem length, spike length and stem diameter were evaluated. Data was statistically analyzed by ANOVA and Tukey test. When planted during late July and early August, cultivars of early cycle (‘Purple Flora’, ‘Rose Friendship’ and ‘White Friendship’) and intermediate cycle (‘Green Star’ and ‘Jester’), produced floral stems of gladiolus in the desired patterns besides as well as having a shorter growth cycle than late cultivars (‘Gold Field’), being recommended for commercial cultivation in Southern Brazil. RESUMO O objetivo neste estudo foi determinar a duração do ciclo em dias e os parâmetros quantitativos de hastes florais de gladíolo em função da data de plantio e do local de cultivo no Rio Grande do Sul/Brasil. Experimentos de campo foram estabelecidos entre 2014-2015 em três locais (Frederico Westphalen, Itaqui e Santa Maria). O delineamento experimental foi o de blocos completamente casualizados, com seis cultivares de gladíolo em três diferentes datas de plantio em cada local como tratamento. Foram avaliadas a mudança do estágio vegetativo para o reprodutivo, o comprimento da haste, comprimento da espiga e diâmetro da haste no ponto de colheita. Os dados foram analisados estatisticamente pela ANOVA e pelo teste de Tukey. Quando plantadas durante o final de julho e início de agosto, cultivares de ciclo precoce (‘Purple Flora’, ‘Rose Friendship’ e ‘White Friendship’) e intermediário (‘Green Star’ e ‘Jester’) produzem hastes florais de gladíolo dentro dos padrões desejados, além de possuir um menor ciclo de crescimento do que cultivares tardias (‘Gold Field’), sendo recomendadas para cultivo comercial no Sul do Brasil.

Effects of planting dates on the growth and grain yield of two indigenous varieties of pearl millet was carried out at the Teaching and Research Farm, Ambrose Alli University, Ekpoma. The experiment was a 2 × 5 factorial scheme fitted into a randomized complete block design with the two varieties of pearl millet (‘Gero Bida’ and ‘Gero Badeggi’) and five planting dates (April, May, June, July and August) replicated three times. The results obtained showed that delays in planting date significantly reduced growth in pearl millet examined. Similar pattern was observed on days to 50 % flowering and grain maturity. Improved growth with early sowing could have allowed increased availability of assimilates that later supported reproductive growth. These assimilates were remobilized under unfavourable climatic condition in the late cropping season to the reproductive structures. ‘Gero Badeggi’ sown in April, had significantly, the highest growth in the measured characters than ‘Gero Bida’ sown in August and other dates. ‘Gero Badeggi’ planted in May had the highest total grain yield (9.33 t ha-1) while ‘Gero Bida’ planted in July had the smallest (4.27 t ha-1). Therefore, ‘Gero Baddegi’ planted in May is a better variety for pearl millet grain production in Ekpoma.

Background This study was conducted to estimate Fusarium head blight (FHB) and crown rot (FCR) disease incidence on wheat and their interaction with cultural methods (cultivar types, planting time, seed rate, crop rotation, and fertilizer practices) that are used in wheat cropping system in the south of Iraq, Basra province. Results The results showed that the mean average of FHB and FCR was 27.2% and 31%, respectively. This displays that very nearly one-third of wheat crop planted in those 14 fields were infected by both diseases but not very severely, except in two fields (D and HM), which were devastating, 54% and 71% and 41% and 52% for FHB and FCR, respectively. The highest level of incidence for both diseases was associated with the earlier and latest planting dates 28 Oct. and 10 Dec., while the lowest was with 1, 10, and 23 Nov. A 200 and 120 kg/ha were the highest and lowest seed rates used in this study. The selected wheat fields differed in their pre-crop rotations (legume, corn, sorghum, okra, and continuous cropping system of wheat) in a previous year. The amount of added fertilizers (urea, DAP, and NPK) to the studied fields was in a high variation. The seven wheat cultivars examined in this study showed different levels of susceptibility to both diseases. Conclusion The results verified that most of the agricultural practices examined in this study were associated with positive correlation for FHB and FCR in the occurrence of disease incidence. Except the cultivar type and fertilizer application had unclear relationship with the incidence of both diseases.

A field experiment was conducted in a plastic house of Horticulture and landscape design department / Agricultural College / Tikrit University during the season 2012 to study the effect of three planting dates (10/1 , 28/1 and 15/2) and two hybrids of cucumber (Summit and Maxeem) by using Split plot system. The treatments were distributed according to Randomized Complete Block Design (R.C.B.D.) with three replications. The results showed that the planting date had no effect in all the studied characters. The Maxeem hybrid showed significant superiority in the fruit length and fruit numbers it gave higher rate reached 16.2718cm and 6.4720gm successively while Summit had significant increasing in fruit diameter , fruit weight. The interaction treatment between the third date and Maxeem hybrid showed significant increment in fruit length whereas the second date of Summit hybrid increased significant in fruit diameter character. The fruit weight character increased significant for the interaction treatment between the third date and Summit hybrid it gave higher rate reached 90.626 gm.

We adapted and used a crop simulation model based on light interception and use efficiency (LINTUL-Cassava) to improve our understanding of water-limited yields of cassava under rain-fed conditions in Southern Togo. Data collected in four different fields in two locations, Sevekpota and Djakakope, during two consecutive growing seasons from 2012 to 2014 were used. Data from Sevekpota in Year 2, when a larger amount of rainfall was received than in Year 1, were used for model parameterisation and calibration. The model was evaluated with data from Year 1 in Sevekpota and Years 1 and 2 in Djakakope. The model calibration and testing results indicated an overall good agreement between simulated and observed storage roots and total biomass dry matter. A decline in leaf area index (LAI) towards the end of the cropping season and the regrowth at the onset of the new rainy season matched fairly well with the simulated dormancy and recovery from the dormancy phase. The model also captured the decline in yield of storage roots due to leaf regrowth at the recovery from dormancy as observed in Sevekpota. Best harvest periods to minimise storage root losses can be identified on that basis. The assessment of the effect of drought as the difference between simulated potential yields, assuming water content at field capacity, and water-limited yields indicated that drought can cause 9–59% loss of yield. The largest yield loss was recorded in Sevekpota in Year 1, and was mainly due to water stress occurring between 78 and 125 days after planting. The best planting period simulated was around mid-February, which is one to two months earlier than the usual planting time in Southern Togo. Further experimental studies are required to confirm this finding and assess how this can practically fit into existing cropping systems. These findings enhance our understanding of water-limited yield of cassava and unveil possibilities of improving it in future.

Three field experiments were conducted to assess the effect of planting date on the incidence of viral diseases and the severity and the susceptibility of the cultivars. Two cultivars of cucumber (Hybrid Tokyo F1 and Poinsett) and one local variety of zucchini (Bolle) were used for the evaluation in May-July 2014, September-November 2014, and February-April 2015. A randomized complete block design with three replications was used for the experiments. Data were collected on disease incidence, severity, and time until first symptoms occurred. Area under severity index progress curve (AUSIPC) and area under disease progress curve (AUDPC) were calculated respectively for disease severity as well as the incidence on each cultivar. The results demonstrate the susceptibility of all cultivars to the tested viral diseases. The effect of planting dates on cultivars was significantly different (P 0.05) in planting date-variety interaction.

As a developing alternative crop in both urban and rural environments in the Pacific Northwest, quinoa (Chenopodium quinoa Willd.) is predominantly sown using direct-seeding technology on small- to large-scale farms. However, the utilization of transplant methodology could allow for earlier planting dates, improved weed control, and quicker maturation. Many urban farmers and gardeners are experienced and equipped to utilize transplant technology and would potentially be quick to adopt this practice. Following a pilot study in 2015, an experiment was conducted in 2016 that compared transplanting and direct-seeding on two farms in the Olympic Peninsula of western Washington state. With transplant and direct-seed treatments at each location, three quinoa varieties were planted at early, mid, and late planting dates. Here, we report that transplanted quinoa possessed higher survival rates, was quicker to reach later developmental stages, and produced higher yields than direct-seeded quinoa. Transplants were more branched and shorter than direct-seeded quinoa plants; however, they also experienced higher rates of lodging. As the planting dates progressed, lodging decreased, and seed yields increased in the transplanted quinoa across all three varieties compared to the direct-seeded quinoa. The utilization of transplants could provide quinoa growers in urban and peri-urban settings with an improved production method.

International audience; Biomass production and partitioning are important for crop production and is influenced by environmental conditions. Sowing date can profoundly influence biomass production and portioning in crop plants depending upon the local climatic conditions. However, the accumulation of biomass in different plant components in annual forages in response to changes in sowing date has not been quantified, especially for semiarid farming systems. A field experiment was conducted during 2011–2013 to investigate how sowing date (early, mid, late) influences biomass partitioning and the interrelationships with environments in four warm-season annual crops in the Loess Plateau of China. The aboveground biomass of all four crops was more reliant on rainfall and solar radiation at flowering and temperature and rainfall at maturity. Solar radiation, rainfall, and temperature had a combined effect on belowground biomass (0–0.3 m), depending on the forage crop. Reductions in biomass in the late-sown treatment were mostly attributed to plant size; the ‘allometry’ among plant components did not change. The changes of shoot: root and leaf: stem ratios were related to the relationship between biomass accumulation and rainfall, temperature and intercepted radiation. It is evident that dry matter allocation patterns in crops must be analyzed using a dynamic approach (allometry) and relate with environmental conditions, rather than a static approach using ratios. The results from this study provide references for crop management in forage production and breeding in semiarid areas.

The information on genotypic responses to the seasonal variation in the starch content, starch yield, and starch quality of cassava is limited. The objective of this research was to investigate the seasonal variation of starch characteristics of three cassava genotypes grown under irrigation. The experiment was conducted at four planting dates (20 April, 30 June, 5 October, and 15 December 2015). Three cassava genotypes (CMR38-125-77, Kasetsart 50, and Rayong 11) were evaluated in a randomized complete block design with four replications and the plants were harvested at 12 months. The planting date contributed the largest portion of the total variation in the starch content, starch yield, and starch granule size. The amylose content variability was heavily influenced by genotype. Cassava planted on 5 October or 15 December had greater starch content, starch yield, and starch granule in most genotypes. This was likely due to a higher temperature and solar radiation during the 3&ndash, 9 months post-planting. CMR38-125-77 showed a consistently high starch content, starch yield, and high amylose content for most planting dates except for the starch yield on 20 April, of which Rayong 11 was the best. These findings will be useful for choosing suitable cassava genotypes for different growing seasons and for facilitating breeding efforts for high starch-yielding and high-quality cassava starch in the future.

Background Considering the potential impact of climate change on the ecology of insect pests, different planting dates and cropping patterns were investigated as farm-level adaption to control insect pests of cabbage and improve productivity. Methods This is a 3 × 4 factorial experiment setup in randomized complete block design including three planting dates (early, normal and late) and four cropping patterns (control—sole cabbage or tomato, tomato intercrop, Piper emulsion and insecticide) with four replications each. Results Cabbage infestation ranged from 1 to 29 and correlated negatively with planting dates or treatments, which differed (P

Late-season heat stress (LSH) is a limiting factor for wheat production. Besides, low zinc and poor protein diet usually is a problem in low-income countries. The primary calorie source in such countries is prepared from bread. This study aims to mitigate heat stress by zinc and nitrogen application and improve zinc and protein content in wheat grain. We did the field experiments as a split-split-plot based on a randomized complete block design with four replications to assess zinc and nitrogen’s possible mitigation effect on LSH and protein and zinc enrichment of wheat grain during two years. Factors included LSH by delay in planting date (optimum, late, and very late) as the main plot, nitrogen (0, 75, 150, and 225 kg ha–1) in subplots, and zinc (0, 10, and 20 kg ha–1) as sub-subplots. We measured yield, yield components, physiological traits, zinc, and protein contents in the grain. Results showed that the highest relative water content and cell-membrane thermal stability were attained at the optimum planting date, 150 kg N ha–1 and 20 kg Zn ha–1. The maximum chlorophyll a and carotenoids contents in wheat cells were recorded in the optimum planting date, 225 kg N ha–1, and 20 kg Zn ha–1. Heat stress reduced the grain yield. In the second year of the experiment, the grain number per unit area was more than that of the first year; however, the highest grain yield was achieved in the first year owing to the higher mean grain weight. Nitrogen application decreased the adverse effects of heat stress on grain yield by increasing the grain number. Zinc application diminished the adverse effects of heat stress by increasing the mean grain weight. The adverse impact of the LSH on grain yield was more than that of biological yield. Heat stress reduced the hectolitre weight and zinc content of the grain. Meanwhile, it increased grain protein. In general, under LSH, the application of 225 kg N ha–1 and 20 kg Zn ha–1 can reduce the adverse effects of heat on the grain quality and quantity.

Understanding the changes in irrigation requirement and possibility of high-temperature stress on major crops are important for food security of Bangladesh. Different water requirement components including potential crop water requirement and potential irrigation requirement were estimated for early, normal and late planting dates of wheat in Bogura using daily observed climate data in CropWat model for 19802013 time period. Significant decreasing trends of reference crop evapotranspiration was found during wheat growing months because of changes in climatic conditions. Potential crop water requirement and irrigation requirement showed significant decreasing trends. Sens rate of decrease of potential irrigation requirement was 1.44, 1.35 and 0.84 mm/year for early, normal and late planting, respectively. On average, the potential irrigation requirement for early planting was only 1.9 mm less compared to normal planting, while for late planting was 32.5 mm higher. High-temperature stress was evident during maturing stage under late planting and during reproductive stage for all planting dates of wheat. Increasing number of high-temperature days for late planting and decreasing number of high-temperature days for early and normal planting were observed during 19802013. Therefore, recent climate change induced high-temperature stress adversely affected wheat cultivation only under late planting conditions. However, climatic water demand did not impose any additional pressure on available water resources during last three decades. [J Bangladesh Agril Univ 2021; 19(2.000): 277-286]

Head size contributes substantially to seed yield of sunflower because it influences both number of seeds per head, and seed size. The aim of this field study was to determine the variability of head diameter in sunflower hybrids depending on planting date across three cropping seasons. Three hybrids (Miro, Rimi, Pobednik) were sown at four planting dates (PD1 - 20th of March, PD2 - 10th of April, PD3 - 30th of April, PD4 - 20th of May). Head diameter was analysed in the stage of flowering and physiological maturity. The trial was arranged as Randomized Complete Block Design (RCBD) with four replications. Analysis of variance (ANOVA) showed that the effect of year, hybrid, planting date and most interactions were highly significant for head diameter in the flowering stage. In the stage of physiological maturity head diameter varied significantly depending only on the planting date. Also, all interactions, except year × hybrid (Y × H), were highly significant. Planting date had significant influence on head diameter in the stage of flowering and physiological maturity in sunflower. With later sowing head diameter increased, so that significantly highest head diameter across planting dates was found in PD4 (11.8 cm in flowering stage, and 22.6 cm at the stage of physiological maturity). Study results may be helpful in the recommendation for optimal planting date in sunflower. [Projekat Ministarstva nauke Republike Srbije, br. TR 31025]

Wheat (Triticum aestivum L.) is one of the major cereal crops and staple food sources in Nepal. Wheat varieties being popular in mid hill regions are still in the early stages of adoption. Identification of appropriate date of seeding plays important role in enhancing the adoption rate ensuring the sustainable production. Therefore, three dates viz 15th November, 1st and 15th December for seeding and twenty eight wheat genotypes were evaluated in a split plot design with two replications for two consecutive seasons in 2011/12 and 2012/13 at an altitude of 2200 masl of eastern Nepal. The results showed genetic differences and interaction effect of genotypes with the dates of sowing on grain yield, panicle length and effective tillers per square meter. The wheat sown on 1st December showed the highest yield as compared to other sown dates. Similarly, WK1907, WK1911, WK1803, WK1915, WK1909, WK1714 and WK1803 produced highest yield among the tested genotypes with retaining maximum number of effective tillers and posed suitable maturity across all sowing date.Journal of Nepal Agricultural Research Council Vol.1 2015 pp.33-36

Since maize, peanut, and cotton are economically valuable crops in the southeast United States, their yield amount changes in a future climate are attention-grabbing statistics demanded by associated stakeholders and policymakers. The Crop System Modeling&mdash, Decision Support System for Agrotechnology Transfer (CSM-DSSAT) models of maize, peanut, and cotton are, respectively, driven by the North American Regional Climate Change Assessment Program (NARCCAP) Phase II regional climate models to estimate current (1971&ndash, 2000) and future (2041&ndash, 2070) crop yield amounts. In particular, the future weather/climate data are based on the Special Report on Emission Scenarios (SRES) A2 emissions scenario. The NARCCAP realizations show on average that there will be large temperature increases (~2.7 &deg, C) and minor rainfall decreases (~&minus, 0.10 mm/day) with pattern shifts in the southeast United States. With these future climate projections, the overall future crop yield amounts appear to be reduced under rainfed conditions. A better estimate of future crop yield amounts might be achievable by utilizing the so-called weighted ensemble method. It is proposed that the reduced crop yield amounts in the future could be mitigated by altering the currently adopted local planting dates without any irrigation support.