Optimum Sowing Date Research Articles

Optimization of sowing dates for enhanced rice yield: insights from field experiments in the middle and lower reaches of the Yangtze River, China

An efficacious strategy to adapt to climate change involves optimizing the planting season, a technique that has been extensively utilized to enhance the use of solar radiation and temperature resources in rice cultivation. Field experiments were executed in the middle and lower reaches of the Yangtze River, China, employing three distinct rice cultivars and seven disparate sowing periods spanning 2019 to 2021. The objective of assessing the impact of sowing date on apparent radiation use efficiency (RUEA), accumulated temperature use efficiencies (TUE), and overall rice yield. Subsequent to the delay of sowing dates, the duration of the comprehensive growth period initially exhibited a declining trajectory before subsequently escalating, with the reduction predominantly ascribed to a decrease in the number of days preceding heading. Furthermore, there was a tendency for both the mean daily and effective cumulative solar radiation to decline over the course of the growing period. The yield of the three rice varieties demonstrated an initial surge, which was then followed by a subsequent decline in reaction to the delay of sowing dates. A correlation analysis disclosed that solar radiation and effective cumulative temperature (EAT) were the predominant elements impacting grain yield. The outcomes of the path analysis indicate that EAT exerts the most substantial influence on yield, succeeded by cumulative total solar radiation (TSR), while photothermal quotient (PTQ) demonstrates the least impact on yield. There was a significant positive correlation between EAT and cumulative TSR with spikelets per panicle (0.237** and 0.218**), grain filling (0.753** and 0.576**), and grain weight (0.339** and 0.359**), respectively. The findings of this study indicate that an increase in yield is facilitated when the EAT after heading exceeds 594.9 ℃, the EAT surpasses 2016.7 ℃, the cumulative TSR before heading is above 1548.7 MJ m− 2, the cumulative TSR after heading is over 603.0 MJ m− 2, and the cumulative total radiation throughout the entire growth period is more than 2151.8 MJ m− 2. Furthermore, the most optimal sowing date, as identified by this study, is June 6. This study provides key insights into boosting rice productivity in the middle and lower reaches of the Yangtze River, China by analyzing the impact of temperature and solar radiation on yield and identifying optimal growth conditions.Clinical trial number Not applicable.

The effect of sowing dates on the yield of soybean (Glycine max (L.) Merr.) accessions differing in maturity schedules under the climate conditions of Irkutsk Province

Background. Soybean is the main supplier of complete vegetable protein and oil. Prior to the emergence of new early-ripening cultivars, this crop was not cultivated in Irkutsk Province. Its introduction into the area requires a detailed study of agricultural practices, primarily the choice of optimal sowing dates. Materials and methods. Soybean cv. ‘Barguzin’, late-ripening under the conditions of Irkutsk Province, and early-ripening accession 15 served as the research objects. Field studies were carried out in 2019–2021. There were four sowing dates, from the first ten-day period of May through the first ten-day period of June. Results and conclusion. Cv. ‘Barguzin’ appeared highly productive under the climate of Irkutsk Province (its average seed yield in 2019–2021 was 2.7 t/ha), but its productivity was significantly influenced by weather conditions and sowing dates (seed yields varied from 1.4 to 3.6 t/ha). The optimal sowing times for this cultivar are the first and second ten-day periods of May. Early-ripening accession 15 was characterized by more stable yield values in the studied years (average productivity was 2.4 t/ha, minimum 1.9 t/ha, and maximum 3.2 t/ha). The preferred sowing times for this accession are the second and third ten-day periods of May. The case study of two soybean genotypes differing in maturation schedules revealed the need for individual selection of sowing dates. It was shown that the early-ripening soybean genotype imposed less stringent requirements on the choice of sowing dates.

Impact of Planting Time on the Performance of Different Wheat Varieties: A Review

Wheat (Triticum aestivum L.) is among the most widely cultivated cereal crops globally. Wheat belongs to family Poaceae and genus Triticum and its center of origin is South Western Asia. Following China, India is the second-largest wheat producer in the world. Among different species of wheat crop, Triticum aestivum is the most prime because of its higher calorific values as well as a good addition for nutritional requirement of human body due to appearance of 9-10 % protein and 60-80 % carbohydrates. Choosing the appropriate sowing time and selecting suitable cultivars are crucial for achieving higher wheat yields. Early sowing with the optimal plant population promotes better growth and nutrient uptake, leading to increased crop production. Delayed sowing reduces the growth, yield, and quality of wheat grain, while early sowing leads to greater yields thanks to a longer grain development phase. Additionally, cultivar selection played a crucial role in determining wheat performance. Some cultivars exhibited greater adaptability to varying sowing dates, maintaining higher yields and better stress tolerance. Proper selection of cultivars is obtained to maximum yield due to variation among the weather conditions and genetic diversity. Optimum sowing dates give suitable temperature to obtain maximum productivity and cultivars selection also play prime role in obtaining maximum wheat production. Improper selection of cultivars produces lower grain yield.

Determination of Appropriate Sowing Date on Fibre Yield and Yield Attributes of Jute (Corchorus olitorius L.) var. BJRI Tossa Pat-8 (Robi-1)

The experiment was conducted at Jute Agriculture Experimental Station (JAES), Manikganj; JRRS, Rangpur and JRSS, Jashore to determine the optimum sowing date of jute var. BJRI Tossa Pat-8. The experiment was laid-out in RCBD with three replications and variety O-9897 used as control. Crops were sown on five different dates i.e., 20 March, 30 March, 10 April, 20 April and 30 April regarded as treatment. Crops were attained recommended cultural practices and harvested at 120 days after sowing. The results showed that BJRI Tossa Pat-8 (Robi-1) sown on 10 April to 20 April gave significantly higher fibre and stick yields at Manikganj (3.37 t ha−1 and 6.33 t ha−1 respectively); Rangpur (3.11 t ha−1 and 5.22 t ha−1, respectively) and Jashore (3.96 t ha−1 and 5.57 t ha−1, respectively) with an average 14% higher than control. Bangladesh Agron. J. 2024, 26(2): 27-33

Maize yield and Fall armyworm damage responses to genotype and sowing date-associated variations in weather conditions

Due to climate disruption and delayed onset of rains, maize is often sown late, outside the optimal window, increasing the impact of pests such as fall armyworm and reducing yields. Identifying optimal sowing dates and the best genotypes is crucial to maximise yields while limiting fall armyworm (FAW) damage. Thus, this study was undertaken to evaluate yield and FAW damage variation in relation to sowing-date weather conditions to determine the optimal sowing window. The experiment had a split-plot design with four genotypes ('PVAH-1 L', 'PVAH-3 L', 'PVAH-6 L' and 'SAM 4 VITA') and four sowing dates (30 November to 14 January and delayed by 15, 30 and 45 days) during the three consecutive cropping seasons. Abundant rainfall and a high number of wet days increase yields while reducing FAW damage. The genotype shows that 'PVAH-1 L' has ear resistance (3.24) and leaf partial resistance (4.05) to FAW, with a high yield (6.54 t.ha−1). In contrast, 'PVAH-3 L' (4.27 and 5.05), 'PVAH-6 L' (4.24 and 4.37) and 'SAM 4 VITA' (4.25 and 4.00) show partial resistance to FAW in both ears and leaves, but have relatively lower yields, except for 'PVAH-6 L' (6.29 t.ha−1). Maize sown on 15 December had a high yield (8.76 t.ha−1), similar to those sown on 30 November. However, sowing on 30 December and 14 January reduced yields by 2 t.ha−1 and 7 t.ha−1 respectively, while increasing FAW infestation and damage. Therefore, in the Lubumbashi region, due to the delayed onset of rains and climatic disturbances, the sowing period can be extended to 30 December, with an optimal window extending from 30 November to 15 December. To maximise yields and limit FAW damage, it is recommended that 'PVAH-1 L' be sown on 15 December, 'SAM 4 VITA' on 30 November or 15 December and 'PVAH-6 L' on 30 November or 15 December.

YIELD AND QUALITY CHARACTERISTICS OF SUNFLOWER (Helianthus annuus L.) CULTIVARS BY DIFFERENT SOWING DATES

A field trial was initiated to ascertain the optimal sowing date for five distinct sunflower cultivars in Turkey’s Mardin Province. The trial scrutinised various parameters including plant height, head diameter, seed yield, protein content, oil content and oil yield. The first sowing produced the highest seed yields (3484 kg ha−1), with the Şems (3255 kg ha−1) and Zuhat (3157 kg ha−1) cultivars producing the highest values. The highest overall oil content was achieved in the second sowing (31.7%) and in the Zuhat cultivar (34.6%). The highest mean oil yields were observed in the Zuhat cultivar (1096 kg ha−1) and in the first sowing (1084 kg ha−1). There was a general decrease in yield as the sowing date was delayed. Winter sowing is suggested for the Zuhat cultivar. If possible, the second sunflower crop should be sown shortly following the harvest of the main crop.

Integrating rainfall index-based insurance with optimal crop management strategies can reduce financial risks for Australian dryland cotton farmers

Drought undermines the financial sustainability of farmers. While farmers have adopted various strategies to mitigate some drought impacts, they remain exposed to substantial drought risk. Insurance could be useful in managing climatic risks and for encouraging farmers to take sensible risks (e.g., changing their sowing date to increase yield), but it can be costly. Here, we tested whether the integration of a change in sowing date with rainfall index-based insurance could improve farmer profitability and income stability. We used the Agricultural Production Systems Simulator (APSIM)-Cotton model to simulate cotton lint yields for various sowing dates, taking into account different management strategies, across three dry-land cotton research farm sites – Dalby, Goondiwindi, and Theodore – from 1940 to 2022. We designed the index-based insurance payout when the average rainfall received during the growing season falls below a predefined level, such as the 5th, 10th, or 20th percentile of rainfall. Our study, which involved 3.9 million cotton lint simulations and 3,000 rainfall index-based insurance products, showed that combining a shift in sowing date with insurance can lead to an income improvement of up to 21.5% at some study sites. Additionally, in drought years, the income improvement for farmers who combined optimal sowing dates with rainfall index-based insurance was up to 48.0%. The framework developed in this study could aid in devising financial strategies to enhance farming resilience during climate extremes.

Optimizing sowing Date for Growth, Yield and Quality of Maize (Zea mays L.) Cultivars in Southern Coastal Region of Bangladesh

Optimizing sowing Date for Growth, Yield and Quality of Maize (Zea mays L.) Cultivars in Southern Coastal Region of Bangladesh

Promoting sustainable smallholder farming systems in China

CONTEXTHundreds of millions of smallholder farmers account for 84% of farming households globally. Owing to the limited access to knowledge and resources, smallholder farming systems under sub-optimal management are facing multiple challenges such as adverse environmental impacts and difficulties in meeting growing food demand. Although substantial advanced techniques and practices have been developed, applying these practices on the ground at a large scale remains a great challenge. OBJECTIVESThis study aims to assess the sustainability of typical soil-crop management practices in order to recommend best practice bundles. The study also deploys a farmer survey in order to identify barriers hindering the adoption of sustainable practices and propose ways to overcome these barriers. METHODSTo achieve these aims, we develop a generalizable framework combining technical innovations and social realization pathway for sustainable transformation of smallholder farming systems. We apply this framework in the North China Plain as a case study, propose target-oriented practice bundles and subsequent realization roadmaps from smallholder farmer's perspectives and interests. RESULTS AND CONCLUSIONSOur results show that nitrogen reduction has the greatest positive effect on the overall sustainability of smallholder farming systems (12–14%), followed by formula fertilizer (6–10%) and optimal crop practices (2–4%). Thus, our recommended practice bundles include reducing fertilizer inputs and optimal sowing date and rate. However, our farmer survey shows that the implementation of these recommended practices faces barriers associated with economic costs, labor requirements, and farmer's preferences and acceptance. We suggest ways to overcome these barriers, including multi-stakeholder platforms better connecting smallholders, scientists, government, and industry. SIGNIFICANCEOur framework can be amended to fit different contexts and targets, therefore it can be adopted and tweaked by other regions worldwide dominated by smallholder agriculture to promote sustainable transformation.

Achieving stable and sustainable Mungbean yields in Australia via optimal sowing dates

ContextAs a rainfed, short-season crop, mungbean is a particularly attractive summer rotation option for Australian farmers, but the rate of mungbean adoption in Australia is low due to its high yield instability. A lack of research conducted on modern mungbean in Australia has hindered farmers’ ability to understand how to best manage the crop and close the yield gap. ObjectivesThe aim of this study was to provide recommendations for optimal sowing windows (balancing maximum yield potential with minimum risk—i.e. instability and crop failure). MethodsWe simulated 60 years of growing mungbean at 180 different sowing times, four different initial soil water levels and at seven sites across Queensland and New South Wales using the new Agricultural Production Systems sIMulator Next Generation (APSIM NextGen) Mungbean model. We then calculated the impact of sowing date on mungbean water use efficiency and on the soil water deficit for the subsequent crop in the rotation. ResultsHigher initial soil water levels decreased risk (instability and failure) at all sites. Arid sites with high evaporative demand had optimal sowing windows later (February) in the growing season. More temperate sites yielded better with higher levels of stability when sown between November and January. Sowing in September/October is not recommended in any site as it coincided with low yield stability and water use efficiency. Not all sites had a clear optimal sowing window. We conclude, therefore, that in some environments, sowing time can only marginally reduce risks in growing mungbean. ConclusionsWe identified optimal sowing window that can reduce risks of a failed crop by 20 % and increase stability without losing yield potential. The timing of the optimal sowing window for a given site appears to be influenced by avoiding periods with high evaporative demand during the reproductive phase. ImplicationsModelling has been critical for exploring the trade-offs between maximizing and stabilizing mungbean yields over a wide range of environments and growing seasons to determine the optimal sowing windows across the main growing environments in Australia.

Response of Spring Maize to Different Sowing Schedules and Phosphorous Application

A field experiment was conducted at the Agronomy Farm, School of Agriculture, Lovely Professional University in 2023 to assess the performance of maize (Zea mays L.) under varying sowing schedules along with levels of phosphorus application. The experimental site featured sandy loam soil with pH of 7.34, 0.32% organic carbon content, and an electrical conductivity (EC) 0.423 ds m-1. An experiment comprised different phosphorus levels, including recommended diammonium phosphate (DAP), recommended single superphosphate (SSP), 10% increase in DAP, or 10% increase in SSP applied at three sowing dates. It followed a randomized block design with twelve treatments and three replications. The results indicated that the timing of sowings had a significant impact on all yield attributes, such as cob length (cm), number of rows/cob, number of cobs/m2 area, grains/cob, grain yield (q/ha), biological yield (kg/ha), and harvest index (%). However, levels of phosphorus application did not exhibit a significant effect on growth and yield attributes. The best results, including taller plants (213.8 cm), a higher number of cobs per m2 area (14), increased number of rows/cob (16), grains per cob (334.7), grain yield (45.2 q/ha), biological yield (97.8 q/ha), and harvest index (53.2 %), were achieved by sowing maize crop at the optimum sowing date (D2).

Spatial and temporal distribution of optimal maize sowing dates in Nigeria.

Climate change and inter-annual variability cause variation in rainfall commencement and cessation which has consequences for the maize growing season length and thus impact yields. This study therefore sought to determine the spatially explicit optimum maize sowing dates to enable site specific recommendations in Nigeria. Gridded weather and soil data, crop management and cultivar were used to simulate maize yield from 1981-2019 at a scale of 0.5°. A total of 37 potential sowing dates between 1 March and 7 November at an interval of 7 days for each year were evaluated. The optimum sowing date was the date which maximizes yield at harvest, keeping all other management factors constant. The results show that optimum sowing dates significantly vary across the country with northern Nigeria having notably delayed sowing dates compared to southern Nigeria which has earlier planting dates. The long-term optimal sowing dates significantly (p<0.05), shifted between the 1980s (1981-1990), and current (2011-2019), for most of the country. The most optimum planting dates of southern Nigeria shifted to later sowing dates while most optimum sowing dates of central and northern Nigeria shifted to earlier sowing dates. There was more variation in optimum sowing dates in the wetter than the drier agro-ecologies. Changes in climate explain changes in sowing dates in wetter agro-ecologies compared to drier agro-ecologies. The study concludes that the optimum sowing dates derived from this study and the corresponding methodology used to generate them can be used to improve cropping calendars in maize farming in Nigeria.

Delayed sowing and its ramifications: biophysical, yield and quality analysis of wheat cultivars in the northwest Indo-Gangetic plains.

The continuous cultivation of rice-wheat in the same field is a key element of double-cropping systems in the Indo-Gangetic plains. Yields of such cropping systems are increasingly challenged as climate change drives increases in temperature, terminal stress and uneven rainfall, delaying rice harvesting and subsequently delaying sowing of wheat. In this paper, we evaluate the optimum sowing dates to achieve high grain yield and quality of wheat cultivars in northwest India. Three cultivars of wheat, HD-2967, HD-3086 and PBW-723, were sown on three different dates at the research farm of ICAR-IARI, New Delhi, to generate different weather conditions at different phenological stages. Different biophysical attributes, photosynthetic rate, stomatal conductance and transpiration rate, were measured at different phenological stages. Yield and grain quality parameters such as protein, starch, amylopectin, amylose and gluten were measured in different cultivars sown on different dates. Biophysical parameters were found to be higher in timely sown crops followed by late-sown and very late-sown crops. Further, the different sowing dates had a significant (P < 0.05) impact on the grain quality parameters such as protein, starch, amylopectin, amylose and gluten content. Percentage increases in the value of starch and amylose content under timely sown were ~7% and 11.6%, ~5% and 8.4%, compared to the very late-sown treatment. In contrast, protein and amylopectin contents were found to increase by ~9.7% and 7.5%, ~13.8% and 16.6% under very late-sown treatment. High-temperature stress during the grain-filling periods significantly decreased the grain yield. Reduction in the grain yield was associated with a reduction in starch and amylose content in the grains. The protein content in the grains is less affected by terminal heat stress. Cultivar HD-3086 had higher growth, yield as well as quality parameters, compared to HD-2967 and PBW-723 in all treatments, hence could be adopted by farmers in northwest India. © 2024 Society of Chemical Industry.

Yield and quality of winter wheat grain under different cultivation technologies

Purpose. Study of the influence of preceding crops and sowing terms on the yield and quality of winter wheat grain. Methods. The study analyzed 11 varieties of soft winter wheat, ‘Podolianka’, ‘MIP Yuvileina’, ‘MIP Fortuna’, ‘MIP Roksolana’, ‘MIP Feieriia’, ‘MIP Vidznaka’, ‘MIP Nika’, ‘MIP Darunok’, ‘MIP Aelita’, ‘MIP Aurika’ and ‘MIP Dovira’. The study investigated the impact of preceding crops (soybean, sunflower, corn/MWR, green manure (white mustard), and mustard/seed) and sowing dates (25 September, 5 and 15 October) on grain yield and baking quality. Results. The research was conducted in 2021–2023 on the experimental fields of the V. M. Remeslo Myronivka Institute of Wheat. The weather conditions were characterized by high tempe­ratures and uneven precipitation. The highest winter wheat yields were obtained after green manure as a preceding crop (7.29 t/ha), and the lowest yields after sunflower (5.35 t/ha). Shifting the sowing date from 25 September to 15 October reduced the average yield of the varieties. The only exception to the results were those obtained after crops such as sunflower and mustard when sown on 5th October, which yielded 5.54 and 6.51 t/ha respectively. The highest yields (6.39–6.95 t/ha) were observed for the varieties ‘MIP Darunok’, ‘MIP Aurika’, ‘MIP Aelita’ and ‘MIP Vidznaka’. Higher protein, gluten and sedimentation values were observed after green manure and soya as a preceding crop; in addition, after soya there was a tendency to increase flour strength and bread volume. The aforementioned shift in sowing date also resulted in a decrease in bread volume and an increase in vitreousness; the remaining parameters were within the range of significant differences. The varieties ‘MIP Dovira’, ‘MIP Nika’ and ‘MIP Roksolana’ were characterized by the highest protein content in the grain. According to the complex of quality indicators, ‘MIP Yuvileina’, ‘MIP Roksolana’ and ‘MIP Aurika’ prevailed over others. Conclusions. It was found that green manure and soybean as a preceding crop, as well as optimal sowing dates – the third decade of September and the first of October – provided the maximum yield of the varieties studied. The varieties with the hig­hest yields were ‘MIP Darunok’, ‘MIP Vidznaka’, ‘MIP Aurika’ and ‘MIP Aelita’. According to the complex of grain quality indicators, the varieties ‘MIP Yuvileina’, ‘MIP Roksolana’ and ‘MIP Aurika’ were distinguished.

Impact of Different Sowing Dates on Growth and Pod Yield of Vegetable Pea under Sub-Himalayan Foothills Region of India

Background: The optimum sowing date is crucial among the different agronomic procedures for maximizing output. Optimizing a crop's planting time may be one of the most significant climate resilient tactics for increasing production and hence it becomes necessary to study the crop growth behaviors in changing climatic conditions. The proposed field investigations were undertaken to study the influence of different sowing dates on yield of vegetable pea. Methods: Field investigations were undertaken during Rabi seasons of 2020-21 and 2021-22 at the Vegetable Research Farm, Department of Horticulture, Dr. Rajendra Prasad Central Agricultural University, Pusa (85.67oE - 25.98oN.), which comes under sub-Himalayan foothills region of India. The research study was performed in Randomized Block Design with three replications consisting of eight different sowing dates of vegetable pea. cv. Azad Pea-3 at 10 days interval between each sowing dates. Observations were made on various growth and yield attributing parameters. Result: Results revealed that the parameters under study were substantially affected by various sowing dates. Second week of sowing in November in the years produced maximum plant height at 60 DAS (83.77cm), number of branches per plant (3.97), number of nodules per plant at flowering (26.13), number of green pods per plant (20.80), 10 pods weight (75.67g) and pod yield (52.06q/ha).

Optimizing sowing dates increase solar radiation to mitigate maize lodging and yield variability: A five-year field study

Optimizing sowing dates (SDs) is a potential strategy for adjusting maize production to climate change and increasing yield. However, there is still a lack of research on the combined effects of lodging and yield in relation to climatic variables across various SDs. This study aims to investigate the changing patterns and distribution of important climatic variables during the maize growth season, their impact on yield and lodging, and the critical factors affecting lodging at crucial growth stages under different SD scenarios. In this study, we assessed the impact of climate change on yield and lodging by conducting field experiments over 5 years (2015, 2016, 2019–2021) encompassing 25 SDs in the Sichuan basin, China. Results demonstrated that the lodging rate had a significant effect on the coefficient of variation (CV, 3.31–10.50%) of maize yield. A 1% increase in lodging rate, led to a decrease of 58.05 kg ha-1 in yield. Changes in SDs notably affected solar radiation (Sr) from emergence to silking (E-R1). Additionally, the study found that Sr explained 34.7% of the lodging rate variation in E-R1. Analysis of historical meteorological data showed notable inter-annual variations in Sr trends, with a decline of -8.7763 MJ m-2 yr-1 from 1990 to 2021, especially noticeable from late May to early July. Variation Partitioning Analysis (VPA) revealed that climatic variables during the period from emergence to physiological maturity (E-R6) and E-R1 explained 43.9 and 53.2% of yield, respectively, across different SDs. These variables also contributed 56.0 and 45.4% to lodging. Using Random Forest (RF) determined that changes in SDs significantly impacted lodging rates mainly through modifications in basal internode morphology, which explained 69.79% of the variation. The study identified optimal sowing dates for achieving high and consistent yields, primarily occurring between late March and mid-April, attributed to increased Sr during E-R1. Overall, this research provides valuable insights into the effects of climate change on stalk lodging and offers guidance on adjusting sowing dates to mitigate maize lodging rates.

Economic and biological characteristics of soft winter wheat variety Krasnoobskaya ozimay

One of the main tasks of modern breeding is to create the varieties that are resistant to negative environmental factors giving consistently high yields in a changing climate. Since 2021, the variety of soft winter wheat Krasnobskaya оzimaya, created by recombination breeding, has been included in the State Register of Breeding Achievements. Its pedigree includes, along with wheat varieties, triticum-agropyrum hybrid and triticale. This variety was evaluated for its economically valuable traits and properties. The studies were carried out in 2015–2022 in the Novosibirsk region. Novosibirskaya 40 was the standard, Novosibirskaya 3 was the control. Krasnobskaya оzimaya variety is recommended for cultivation in the forest-steppe zone of the West Siberian region. It is medium maturing, has rather high winter hardiness (60.0%) and resistance to lodging (4.1 to 4.7 points) with plant height up to 101 cm. The weight of 1000 grains averages 37.9 g. The variety has a high coefficient of productive tillering (5.3 pcs.). Over the years of the study, the average yield of the variety was 5.03 t/ha. On average, according to the results of the tests in the state variety test plots of the Novosibirsk region the yield amounted to 4.34 t/ha, the maximum yield was observed at the Maslyaninsky variety test plot – 4.9 t/ha, which is 1.14 t/ha higher than the standard. According to the results of the ecological test, the yield exceeded the varieties Novosibirskaya 40 and Novosibirskaya 3 by 0.74 and 0.41 t/ha, respectively, winter hardiness was at the level of the standards. High and stable yield of this variety is formed due to a number of economically valuable features: productive bushiness, weight of 1000 grains, resistance to lodging, winter hardiness. According to the results of the study, it was determined that the optimal sowing date of the Krasnobskaya оzimaya variety is September 1 with a shift of 1–3 days in both directions.

Effectiveness of pre-sowing treatment with plant growth regulators to improve the productivity of &lt;i&gt;Astragalus babatagi&lt;/i&gt; and &lt;i&gt;A. xanthomeloides&lt;/i&gt;

In 2022, under the conditions of the growing experience of the IHR of the Academy of Sciences of the Republic of Uzbekistan on plants Astragalus babatagi and Astragalus xanthomeloides, optimal sowing dates and options for seed treatment with plant growth regulators and organo-mineral fertilizer were studied. The positive effect of pre-sowing seed treatment was revealed, which significantly affected the increase in seed productivity and plant phytomass. It was found that pre-sowing treatment of Astragalus babatagi seeds with Uchkun plus, Floroxan and potassium Humate Prompter preparations contributed to an increase in seed yield from one bed by 1.0, 0.98 and 0.8 g relative to scarified seeds and an increase in phytomass yield by 189, 197 and 186 g, respectively. The increase in the yield of Astragalus xanthomeloides seeds from one bed in experimental versions using Uchkun plus, Floroxan and potassium Humate Prompter increased by 0.92, 1.05 and 0.62 g, respectively, compared with the “scarification” option, and compared with the control by 1.82, 1.95 and 1.52 g, respectively. The yield of phytomass increased by 53.7, 61.2 and 30.7 g relative to the variant of scarified seeds, whereas in relation to the control these indicators increased by 103, 110 and 79.8 g, respectively.

A case study on the impacts of future climate change on soybean yield and countermeasures in Fujin city of Heilongjiang province, China

Global climate change poses a great impact on crop growth, development and yield. Soybean production in Northeast China, which is one of the traditional dominant soybean production areas in China, is of great significance for developing the domestic soybean industry and reducing dependence on imported soybeans. Therefore, it is crucial to evaluate the impacts of future climate change on soybean yield in Northeast China, and to propose reasonable adaptation measures. In this study, we took Fujin city of Heilongjiang province in Northeast China as an example, and used the CROPGRO-soybean model in DSSAT (Decision Support System for Agrotechnology Transfer) to simulate the impacts of future climate change on soybean yield in the four periods of the 2020s (2021-2030), 2030s (2031-2040), 2040s (2041-2050) and 2050s (2051-2060) under two representative concentration pathway (RCP) scenarios (RCP4.5 and RCP8.5), and further determine the best agronomic management practices. The results showed that the calibrated and validated model is suitable for simulating soybean in the study area. By analyzing the meteorological data under future climate scenarios RCP4.5 and RCP8.5 from the PRECIS regional climate model, we found that the average temperature, cumulative precipitation and cumulative solar radiation would mostly increase during the growing season in Fujin city of Heilongjiang province. Combined with the model simulation results, it is shown that under the effect of CO2 fertilization, future climate change will have a positive impact on soybean yield. Compared to the baseline (1986-2005), the soybean yield would increase by 0.6% (7.4%), 3.3% (5.1%), 6.0% (16.8%) and 12.3% (20.6%) in the 2020s, 2030s, 2040s and 2050s under RCP4.5 (RCP8.5).Moreover, the optimal sowing dates and the optimal supplemental irrigation amount under RCP4.5 (RCP8.5) are May 10 (May 5) and 50 mm (40mm), respectively. Under future climate conditions, the agronomic management practices, such as advancing the sowing date and supplementary irrigation in the key stage of soybean growth would increase soybean yield and make soybean growth more adaptable to future climate change.

Simulating the effects of optimizing sowing date and variety shift on maize production at finer scale in northeast China under future climate.

Global warming and the rising occurrences of climate extremes have become formidable challenges for maize production in northeast China. The optimization of sowing date and variety choice stand out as two economic approaches for maize to enhance its resilience to climate change. Nevertheless, assessment of the potential of optimizing sowing date and variety shift on maize yield at finer scale remains underexamined. This study investigated the implications of optimizing sowing date and implementing variety shift on maize yield from a regional perspective. Compared to the reference period (1986-2005), climate change would decrease by 11.5-34.6% (the range describes the differences among climate scenarios and agro-ecological regions) maize yield in the 2050s (2040-2059) if no adaption measure were to be implemented. The combined adaption (optimizing sowing date and variety shift) can improve maize yield by 38.8 ± 11.3%, 42.7 ± 9.7% and 33.9 ± 7.6% under the SSP1-2.6, SSP2-4.5 and SSP5-8.5 scenarios, respectively. The current sowing window typically falls within the projected optimal sowing window, defined as the period capable of achieving 90% of the maximum yield within the potential sowing window under future climate conditions. Consequently, the potential of the effect of optimizing sowing window on maize yield is limited. In contrast, variety shift results in higher yield improvement, as temperature rise creates favorable conditions for transplanting varieties with an extended growth period, particularly in high latitudes and mountainous regions. Under future climate, cumulative precipitation and compound drought and hot days during maize growing seasons are two key factors influencing maize production. The optimization of sowing date and variety choice can improve maize yield in northeast China. In addition, maize production should consider varieties with longer growth period and drought and heat tolerance to adapt to climate change. © 2023 Society of Chemical Industry.