Early Sowing Dates Research Articles

Influence of sowing time on the productivity of narrow-leafed lupin under conditions of the Krasnoyarsk Forest-steppe

Experimental work was carried out in 2021–2023. in order to study the influence of sowing timing on the productivity of angustifolia lupine in the conditions of the Krasnoyarsk forest-steppe. The objectives of the research included determining the effect of the timing of sowing angustifolia lupine on seed germination and the safety of plants for harvesting; studying the influence of crop sowing timing on grain yield; assessment of the contribution of factors to the formation of lupine grain yield. The experimental design included three dates for sowing lupine: 1st date (early) – May 5; 2nd term (middle) – May 15; 3rd deadline (late) – May 25. The objects of research were narrow-leaved lupine varieties bred by the All-Russian Research Institute of Lupine Vityaz and Belozerny 110. The hydrothermal regime of growing seasons differed according to the years of observation: in June 2021, as well as in July and August 2022, plants experienced a lack of heat; in 2021 and 2023 there will be a moisture deficit. The research results showed that the field germination of seeds varied according to the experimental variants and depended on the moisture supply of the soil at the sowing depth, which developed under specific growing season conditions. The best seed germination of the Vityaz variety was noted at early sowing dates in 2021 and 2022, and at late sowing dates in 2023; for the Belozerny variety 110 at the average sowing time in 2021, at the late sowing time in 2022 and in 2023. The safety of plants for harvesting decreased from the first sowing period to the third for both the Vityaz variety and the Belozerny 110 variety. Early sowing of lupine provides the highest grain yield of the crop. On average over the years of the experiment, the yield of the Vityaz variety during early sowing was 12.4 c/ha; during the average sowing period, the crop productivity was 12.9% lower, and at the late sowing period it was 50.8 % lower. A similar trend is observed in the variety Belozerny 110: in the 1st sowing period the average yield was 12.2 c/ha, in the 2nd period it was 11.5 % less, in the 3rd period it was 44.3% less. The formation of lupine productivity is significantly dependent on both the timing of sowing (contribution of the factor – 34.7–47.4 %) and on the growing season conditions (contribution of the factor – 39.6–51.9 %).

Урожайность костреца безостого сорта Удалец и элементы ее структуры при разных сроках сева

The article presents the results of three-year studies on the sowing dates of the new 'Udalets' variety of awnless brome when cultivating for seed purposes. In the forest-steppe conditions of the Middle Volga region, spring (3 dates), summer (3 dates), and autumn dates were considered. The studies established the advantage of spring sowing dates in terms of plant density, including productive stems, plant height, in-florescence length, and, ultimately, seed yield over two years of use. The greatest number of productive stems in the first year of use — 214–242 pcs/m2 with a plant height of 127–128 cm was obtained with early spring sowing dates. In the second year of use, with the same sowing dates, the greatest number of generative shoots was also formed — 192–221 pcs/m2. The highest seed yield was obtained with spring sowing dates — 665–950 kg/ha (in the first year of use), 510–550 kg/ha (in the second year). With late June, August and September sowing dates, the yield was only 35–39 kg/ha or 95.5–96.0% lower than with early spring sowing. Low seed yield with these sowing dates is explained by dry conditions in the year of sowing, as a result of which the seeds did not germinate for a long time, did not have time to ver-nalize and form generative shoots.

Effect of Sowing Date on Some Agronomical Characteristics of Rye Cultivars in Iraq

The introduction of rye cultivation in Iraq necessitates the implementation of agrotechnological experiments. Two-year irrigated field experiments were carried out in Al-Muthanna Governorate (in the southwestern region of Iraq) in 2021/2022 and 2022/2023 to evaluate the performance of three European rye cultivars introduced to Iraq, focusing on the most significant agronomical and morphological characteristics. Three sowing dates (01 November, 15 November and 01 December) were tested in a split plot, randomized complete block design. We observed that both the cultivar and sowing date, but not the crop year, influenced the studied characteristics. In general, the early sowing dates enhanced the growth and development of rye and resulted in a higher yield compared to the later sowing dates. We observed that all evaluated rye cultivars can be grown safely in the agroclimatic and soil characteristics of this region. The grain yield was 3.1, 4.2 and 6.9 t ha−1 on average for all the sowing dates, and the above ground biomass results were 13.6, 12.0 and 22.9 on average for all sowing dates in ‘Krzyca’, ‘Dańkowskie złote’ and ‘Horyzo’, respectively. In addition, the highest grain yield (8.8 t ha−1) was harvested in ‘Horyzo’ when it was sown on 01 November; thus, we recommend choosing ‘Horyzo’ for cultivation in Iraq and sowing it in early November. Although further study is required to improve agro-technology (such as the nutrient supply) by using a larger number of cultivars, we can conclude that rye can be grown safely in Iraq under irrigated conditions.

Influence of sowing dates and weed management practices on weed dynamics, productivity and profitability of direct seeded rice

This study evaluated the impact of differential sowing windows and improved weed management strategies on weed dynamics, productivity, and economic viability of direct drum seeded rice (Oryza sativa L.) in the temperate agro-ecosystem of Kashmir. A two-year field experiment was conducted utilizing a split-plot design with two sowing dates (May 10 and June 3) as main plots and six weed management practices as sub-plots. The earlier sowing date (May 10) resulted in significantly enhanced leaf area index, crop growth rate, relative growth rate, net assimilation rate, and grain and straw yields compared to the later sowing (June 3). Among weed management treatments, four mechanized conoweedings (equivalent to weed-free conditions) and sequential application of bensulfuron methyl + pretilachlor (60 and 600 g a.i. ha−1) as pre-emergence followed by 2,4-D (0.75 kg a.i. ha−1) as post-emergence demonstrated superior efficacy in weed suppression and augmentation of crop growth parameters and yield attributes. These treatments also exhibited the lowest weed index and highest benefit–cost ratio. The May 10 sowing, coupled with efficacious weed control measures, significantly reduced weed density and biomass while concomitantly improving nutrient uptake and economic returns. The results indicate that adopting a May 10 sowing date for direct seeded rice, in conjunction with either four conoweedings or the aforementioned sequential herbicide application, can optimize agronomic productivity and economic profitability under the temperate conditions of Kashmir. The study aided in choosing the best sowing window and efficient weed management strategy for attaining higher productivity and profitability of direct seeded rice in temperate conditions.

Improving Cotton Fiber Quality Through Strategic Sowing: Implications for Phosphorus Management from Experiments in Chato District, Tanzania

ABSTRACT This study was conducted in Msilale Village, Chato District in Tanzania, to evaluate the influence of sowing dates and phosphorus levels on cotton fiber quality. The study was established according to a factorial trial, with varying sowing dates (25th November 2022, 15th December 2022 and 4th January 2023) and phosphorus levels (control, 20 kg P ha−1, 40 kg P ha−1, 60 kg P ha−1). Results revealed that early planting had a statistically significant (p < .001) effect on fiber cotton quality, including spinning coefficient index, fiber length, fiber strength, uniformity index, short fiber content, and grade/color. Early sowing dates (25th November 2022 and 15th December 2022) consistently produced superior fiber quality, including spinning coefficient index (156.5 and 148.4), moisture content of the fiber (7.8% and 7.7%), micronaire (3.5 μg/inch), upper half mean length (1.2 cm), uniformity index (84.6% and 84.2%) and shorter fiber (6.8% and 7.0%) relative to late sowing (4th January 2023). Conversely, phosphorus levels did not significantly (p > .05) impact these parameters within the tested range. This research underscores the critical role of selecting appropriate sowing dates for cotton cultivation to achieve better fiber quality.

Bплив ранньовесняних строків сівби насіння ромашки лікарської на польову схожість та виживання рослин в умовах правобережного лісостепу України

An important place in the effective technology of growing medicinal chamomile (Matricaria recutita L.) is occupied by the early spring sowing period. Therefore, they provide a dense emergence of seeds, as evidenced by many conducted scientific studies in the field of plant breeding. The article presents the results of experimental research on the effect of early spring sowing dates of medicinal chamomile on field seed germination and plant survival. It was established that medicinal chamomile plants depended on weather and climatic conditions, sufficient amount of moisture in the soil, soil crust, which as a result led to variation in the passage of growth and development phases, and therefore, a question arose in the study of agrotechnical techniques aimed at the productivity of medicinal raw materials. The cultivation of tetraploid of medicinal chamomile variety Perlyna Lisostepu and Zloty Lan in the conditions of the Right-Bank Forest-Steppe of Ukraine during the period of research (2018-2023) in the early spring sowing period was studied. It was established that the investigated varieties of medicinal chamomile had the highest field germination of seeds due to the content of productive moisture. The highest field seed germination rates of 74.16% were recorded during the early spring (15-18.04) sowing period of the Perlyna Lisostepu variety, and the Zloty Lan variety was 72.68%, respectively. According to six-year research data, the highest field seed germination of 68.00% on the control variant (1-3.04) according to the sowing dates was noted in the Perlyna Lisostepu variety, and the lowest 67.00% – in the Zloty Lan variety. The maximum rate of plant survival at the end of the growing season was 88.96%, which was obtained in the variant of the early spring (15-18.04) sowing period of the Perlyna Lisostepu variety, the minimum rate was 69.15% in the control (1-3.04) of the Zloty Lan variety. The germination rate on average over six years exceeded the control by 6.14%, and the survival of chamomile plants on average over the years of research exceeded the control option by 1.5%. The difference in factors was insignificant (2-3%)

Influence of climatic variables on maize grain yield and its components by adjusting the sowing date.

Yield and its components are greatly affected by climate change. Adjusting the sowing date is an effective way to alleviate adverse effects and adapt to climate change. Aiming to determine the optimal sowing date of summer maize and clarify the contribution of climatic variables to grain yield and its components, a consecutive 4-year field experiment was conducted from 2016 to 2019 with four sowing dates at 10-day intervals from 5 June to 5 July. Analysis of historical meteorological data showed that more solar radiation (SR) was distributed from early June to mid-August, and the maximum temperature (Tmax) > 32°C appeared from early July to late August, which advanced and lasted longer in 1991-2020 relative to 1981-1990. Additionally, the precipitation was mainly distributed from early June to late July. The climate change in the growing season of summer maize resulted in optimal sowing dates ranging from 5 June to 15 June, with higher yields and yield stability, mainly because of the higher kernel number per ear and 1,000-grain weight. The average contribution of kernel number per ear to grain yield was 58.7%, higher than that of 1,000-grain weight (41.3%). Variance partitioning analysis showed that SR in 15 days pre-silking to 15 days post-silking (SS) and silking to harvest (SH) stages significantly contributed to grain yield by 63.1% and 86.4%. The extreme growing degree days (EDD) > 32°C, SR, precipitation, and diurnal temperature range (DTR) contributed 20.6%, 22.9%, 14.5%, and 42.0% to kernel number per ear in the SS stage, respectively. Therefore, we concluded that the early sowing dates could gain high yield and yield stability due to the higher SR in the growing season. Meanwhile, due to the decreasing trend in SR and increasing Tmax trend in this region, in the future, new maize varieties with high-temperature resistance, high light efficiency, shade tolerance, and medium-season traits need to be bred to adapt to climate change and increased grain yield.

Soybean yield dependence on the timing of sowing in the conditions of the foothill zone of the RNO-Alania

The article presents the results of research on the reaction of soybean plants depending on the timing of sowing in the foothill zone of the Republic of North Ossetia-Alania. The need to improve the timing of sowing occurs with the introduction of new varieties of various ripeness in the main and intermediate crops. The purpose of the paper is to study the effect of sowing dates on the yield of soybean seeds in the conditions of the foothill zone of the RNO-Alania. The scientific novelty was to establish optimal sowing dates that would ensure optimal plant growth and development and high productivity. Our research was carried out in the experimental fields of the North Caucasian Research Institute of Mountain and Piedmont Agriculture of the VSC RAS in 2018-2021. The object of research was the varieties of breeding of the Federal scientific center "V.S. Pustovoit All-Russian Research Institute of Oil Crops. Two main types of soils prevail in the foothill zone: chernozems of varying degrees of leaching, as well as meadow and meadow-boggy soils. The arable layer contains from 3 to 4.4% humus. Down the profile, the amount of humus decreases gradually. The reaction of the soil solution in the upper horizons is neutral, in horizons deeper than 80-90 cm – slightly alkaline. The predecessor of the experimental plots was corn for grain. It was found that at early sowing dates (April 20 - May 5) resulted in higher field germination (87-93%), plant foliage of 46.9 thousand m2/ha and their survival rate for harvesting 84-91%. More nodules formed on the roots of the plants. The maximum yield is 2.6 t/ha, obtained during sowing on April 30.

ЭЛЕМЕНТЫ ТЕХНОЛОГИИ ВОЗДЕЛЫВАНИЯ СОИ В РСО-АЛАНИЯ

The author presents the results of research on the study of sowing dates for soybean yields in the conditions of the forest-steppe zone of the Republic of North Ossetia-Alania. With the introduction of new varieties of various ripeness in the main and intermediate crops, there is a need to improve the timing of sowing. The purpose of the work is to study the effect of sowing dates on the yield of soybean seeds in the conditions of the foothill zone of the Russian Federation. The scientific novelty was to establish optimal sowing dates that would ensure optimal plant growth and development and high productivity. Our research was carried out in the experimental fields of the North Caucasus Scientific Research Institute of Mountain and Foothill Agriculture of the VNC RAS in 2018-2021. The object of research was the varieties of breeding of the Federal Scientific Center of the V.S. Pustovoit Research Institute of Oilseeds. Two main types of soils prevail in the foothill zone: chernozems of varying degrees of leaching, as well as meadow and meadow-marsh soils. The arable layer contains from 3 to 4.4% humus. Down the profile, the amount of humus decreases gradually. The reaction of the soil solution in the upper horizons is neutral, deeper than 80-90 cm – slightly alkaline. The predecessor of the experimental plots was corn for grain. It was found that at early sowing dates (April 20 – May 5), higher field germination (87-93%), plant foliage of 46.9 thousand m2/ha and their survival rate for harvesting 84-91% were noted. More nodules formed on the roots of the plants. The maximum yield is 2.6 t/ha, obtained during sowing on April 30. In the forest-steppe zone, the yield of medium-ripened varieties decreased from early to late sowing periods by 0.44 and 0.58 t/ha, while in early-ripening varieties it was less significant. Fertilizers (R90K30) increased the yield of seeds, depending on the timing of sowing, by 0.24-0.58 t/ha.

Effect of plant spacing and sowing dates on the growth and yield of radish (Raphanus sativus) in Rupandehi district, Nepal

A field experiment was conducted from mid-April to mid-June 2022 in Rupandehi to evaluate the growth and yield of radish maintained in varied plant spacing at differed sowing dates. The study was aimed to compare the growth, production and economics of radish in Rupandehi district under different plant spacing and sowing dates and to evaluate the interaction between these two factors. Four plants spacing (10 cm, 20 cm, 30 cm and 40 cm) with constant row spacing was maintained at two sowing dates (Chaitra 29 and Baisakh 14). The treatments were arranged in two factorial Randomized Complete Block Design (RCBD) with 3 replications. The data were collected on 30 DAS and 45 DAS. The obtained data were recorded and analyzed using MS-Excel and R-studio, respectively. The results revealed that the highest yield was obtained from plant spacing of 20 cm (28.20 t/ha). However, individual plant weight was higher in wider spacing. Plant spacing of 20 cm showed significantly highest plant height (24.52 cm), number of leaves per plant (22.37) and leaf length (23.36 cm). Leaf blade width (10.67 cm) and petiole length (3.05 cm) was significantly highest in plant spacing of 30 cm. Early sowing date showed significantly better results for all growth and yield parameters and yield except leaf blade width. Higher gross return, net return and B:C ratio was observed in plant spacing of 20 cm and early sowing date. The study concluded that plant spacing of 20 cm and earlier sowing date was ideal for maximum growth and yield of radish in Rupandehi district.

Sunflower (Heliánthus ánnuus) Yield and Yield Components for Various Agricultural Practices (Sowing Date, Seeding Rate, Fertilization) for Steppe and Dry Steppe Growing Conditions

The dynamics of the productivity of the sunflower hybrid “Baiterek 17” were studied for rainfed conditions of the steppe and dry steppe zones of Kazakhstan for two fertilizer levels (without fertilizers and with the application of a nitrogen-phosphorous fertilizer), two sowing dates, and three seeding rates. The growing season duration varied among zones and was affected by sowing dates. An increase in duration (3–5 days) was observed for the early sowing date and fertilized treatments, regardless of the zone. Increasing the seeding rate for all treatments by sowing date and fertilizer application reduced the duration of the growing season by 3–6 days. The fertilizer application did not affect the formation of seedlings in the study areas. In the dry steppe zone, from 2.5 to 4.8 plants/m2 were formed before harvesting, with an increase in the number of plants at the high seeding rate (57,000 seeds/ha). In the steppe zone, the same pattern was preserved: from 3.5 to 4.9 plants/m2 at a seeding rate of 65 thousand seeds/ha. The maximum diameter and weight of the flower head were found for the early sowing date and fertilized treatments at a low seeding rate, with a strong effect on the yield for both the steppe and dry steppe zones in 2022. On average, for both years, the highest yield for the dry steppe zone was obtained for the sowing date of 15 May and at a seeding rate of 57,000 seeds/ha, while for the steppe zone, the highest yield was obtained for the 10 May planting date and at a sowing rate of 65,000 seeds/ha. Improving plant nutrition and increasing the plant density up to a seeding rate of 65,000 seeds/ha for the early sowing dates (10 May) increased the plasticity in the steppe zone. For the dry steppe zone, the plasticity of the hybrid decreased, but the highest plasticity was also obtained for an earlier sowing date (15 May) and at a seeding rate of 57,000 seeds/ha crop. The study shows that the hybrid “Baiterek 17” has a high ecological plasticity under changing environmental conditions and, with an increase in moisture availability, it requires intensive agricultural practices (fertilization, increased seeding rate, and early sowing dates) to obtain a high yield.

Phenology and yield response of wheat varieties as influenced by sowing dates at gonde and ardayita seed production farm, Ethiopia

Wheat is one of Ethiopia's main foods, contributing to daily caloric consumption. Due to environmental conditions such as distribution and length of the rainy season shifting from time to time elsewhere, particularly at Gode and Ardayita seed production farm, sowing timing and varietal selection are key factors for low yield of wheat crop. This Experiment was designed in a randomized complete block design with three-replications which contain four sowing dates, ranging from June 17 to July 18 at ten-day intervals, and four wheat varieties namely Kingbird, Hidase, Picaflor, and Ogolcho combined to form 16 treatments. According to the result, on days to heading, there was a significant interaction effect of variety and location and the highest number of days (70.42) was obtained at the Ardayita location on Kingbird variety. On the day of heading, there is also a substantial interaction effect of location and sowing date, the maximum days (72.00) were observed at Ardayita on the early sowing date (June-17). The maturity dates of the two locations varied significantly, the longer (116.17) days were recorded at Ardayita. The effect of variations on days to maturity of varieties also significant, Ogolcho variety had the highest maturity (120.04) days. Date of sowing also has a significant effect on maturity date; the highest number of days (116.96) was recorded on June 17 sowing date. The grain filling period significantly vary among the varieties, the Ogolcho variety had the highest number of days (53.25). Grain filling period also had significant variation on date of sowing; the earliest sowing date (June 17) has the longest date (49.96). On the other hand, location had no effect on the grain-filling period, plant height and seed yield. Sowing date and location significantly interact on grain yield of wheat. The maximum (6.38 ton ha-1) seed yield was recorded at Gonde location on second (June 28) sowing date and Ardayita place obtained highest yield at first sowing date (June 17). There was a significant interaction between sowing date and varieties on yield of wheat. From the result Hidasse variety obtained highest yield (6.58 ton ha-1) on the second sowing date (June 28) whereas the Ogolch variety recorded highest (6.28 ton ha-1) at the first sowing date (June 17). Res. Agric. Livest. Fish. Vol. 10, No. 2, August 2023: 133-145

Effects of Seeding Rates and Sowing Times on Grain Yield and Yield Components in Rye (Scale cereale L.) Under Dry Condition

Rye is one of the most important cereals for marginal land and cold climates in Turkey. A 2 year experiment was conducted in Kırşehir, Turkey, to determine the impact of seeding rates and sowing times on rye (Secale cereale L. ‘Aslım 95). Rye seed was sown in different sowing times (1th October, 15th October, 1th November, 15th November and 1th December) at four seeding rates (300, 400, 500 and 600 seeds m−2). A split-plot design was used, with sowing times as main plots and seeding rates randomized as subplots. Grain yield tended to increase with earlier sowing dates and higher seeding rates, based on two-year means. Seeding rates and sowing dates interaction effects on grain yield were significant. Therefore, the highest grain yield with 397.7 kg da-1 was obtained from the highest seeding rate (600 seeds m−2) at the second sowing date (15th October). In contrast, the lowest grain yield (92.8 kg da-1) was obtained from the lowest seeding rate with the delayed sowing dates. It is concluded that the present study showed that the reduction in grain yield depended on sowing time and seeding rates, which led to a significant reduction of number of fertile spike per unit area.

The influence of seeding rates on the yield of pea grain in the conditions of the Pre-Ural steppe of the Republic of Bashkortostan

Relevance. Leguminous crops are the main source of vegetable protein in the world, among which pea is the most common in Russia. Among agrotechnical practices, the seeding rate plays an important role in forming the yield of this crop and obtaining high and stable grain yields. The purpose of the work is to study the influence of various seed sowing rates on the yield of pea varieties in the Republic of Bashkortostan. The experiments were carried out in the conditions of the Pre-Ural steppe subzone in 2017–2020. Pea varieties Chishminskiy 95, Chishminskiy 229, Pamyati Khangilʼdina, Pamyati Popova served as the material for the study.Methods. Sowing qualities of seeds were determined in accordance with GOST 12038-84, GOST 10968-88, GOST 12042-80, GOST 12036-85. Field assessments, phenological observations were carried out according to the methodology of the State cultivar testing of agricultural crops.Results. In our experiments, different conditions of moisture supply, illumination and nutrition of pea plants, due to different seeding rates, had a significant impact on the grain yield in the studied varieties. The increase in the number of plants preserved for harvesting, which depends on their survival and the number of seedlings, was accompanied by an increase in yield. It has been established that pea varieties Chishminskiy 95, Chishminskiy 229, Pamyati Khangilʼdina and Pamyati Popova form the highest and most stable grain yields at early sowing dates with a seeding rate of 1.2 million pieces of germinating seeds per 1 ha. With a decrease in the seeding rate, the weediness of crops increases, and with an increase in the seeding rate, pea plants experience a lack of moisture and nutrients, which leads to a decrease in yield by 0.4–1.0 c/ha.

Features of the winter common wheat variety ‘Zodiak’ when cultivating it according to various forecrops and sowing time

The current study was carried out in the southern part of the Rostov region in the agrotechnical crop rotation of the laboratory for grain cultivation technology. The purpose of the study was to determine the effect of such factors as a forecrop and sowing time on productivity and grain quality of the winter common wheat variety ‘Zodiak’. During the study, there was found that the variety ‘Zodiak’ produced up to 9.70 t/ha. There was established that the high adaptability of the variety ‘Zodiak’ made it possible to obtain high yields at different sowing dates, however, there was a tendency to form maximum productivity when sowing at the optimal time for the area (20 and 30 of September). There was found that the large productivity of the crop sown in black fallow was ensured by the number of productive stems (up to 596 pcs/m2) and productivity per head (number of kernels per head up to 31.3 pcs., grain weight per head up to 1.42 g). For all forecrops in the variant with a late sowing time, there was a decrease in number of kernels per head (by 6.2–22.9 %) and mass of grain per head (by 1.7–11.7 %) compared with earlier sowing dates. Biochemical analysis has shown that when sown in black fallow and after peas, the yielded grain had the maximum protein per-centage on average up to 14.1 % and 13.3 %, respectively. There has been established that the variety ‘Zodiak’ could form high-quality grain even when it was sown after sunflower (with 12.3–12.6 % of protein and 22.5–23.5 % of gluten). The best economic indicators in the cultivation of the variety ‘Zodiak’ were obtained when it was sown in black fallow, with up to 191 % of profitability, up to 77993 rubles/ha of conditional net income.

Amino acid content in the grain of naked oats under various cultivation conditions

The results of studying the formation of yield and amino acid content in the grain of naked oats varieties of different ripeness groups under the influence of different sowing dates are presented. The research was carried out in 2018-2020 in field and laboratory experiments on the medium early Gavroche variety and the mid ripening Ofenya variety in Western Siberia. A significant advantage of early sowing dates of naked oats varieties has been revealed: the Gavroche variety has an average of 25.9-29.6%, the Ofenya variety has 16.2-21.6% relative to later dates. At the same time, a significantly higher yield was formed in the mid ripening variety Ofenya, by 0.1-0.4 t/ha. A greater number of essential amino acids in the Gavroche variety was noted at a late sowing period – 4.51% (at an early and average term of 4.39 and 4.45%, respectively), and interchangeable amino acids – at an early term – 8.83% (at an average and late – 7.80 and 8.46%, respectively). In the Ofenya variety, the content of essential amino acids was 4.82-6.49 g/kg, interchangeable 7.28-9.49%. At the same time, this variety has a tendency to increase the quantitative composition of amino acids in the grain from the early sowing period to the late one. Differences in the influence of moisture conditions on the accumulation of amino acids in the varieties of naked oats were revealed. The highest content of essential and interchangeable amino acids in the medium-ripened variety Ofenya is formed at elevated values of the hydrothermal coefficient (HTC) in the period of seedling – tillering (r = 0.9467 ... 0.9999 at R = 0.6660), reduced values in the period of booting – flowering (r = -0.9338...-0.9987 at R = 0.6660), with an increase in HTC during the filling – ripening period (r = 0.4335... 0.7888 at R = 0.6660). In the early-maturing Gavroche variety, a higher content of essential amino acids was noted at an early sowing period under conditions of low values of HTC during the period of seedling – tillering, increased - during the period of booting-flowering and arid conditions of the period of filling–ripening - r = -0.8812, 0.8626, -0.6087 at R = 0.6660, respectively. The high content of interchangeable amino acids in the Gavroche variety was formed at late periods in the years with reduced values of HTC during the period of seedling – tillering, the presence of precipitation during flowering and their absence during the period of filling-ripening (r = -0.8287, 0.8068, -0.6860 at R = 0.6660, respectively).

Influence of Sowing Dates on Growth and Yield Attributes of Linseed (Linum Usitatissimum L.), Varieties in Horo Guduru District, Western Ethiopia

A field experiment was conducted at Harato and Gitilo sites during the 2019/20 and 2020/21 years. This study aimed to determine the effects of sowing dates on seed yield attributes of linseed (Linum usitatissimum L.) varieties and to identify the effect of linseed varieties on growth and yield attributes at both sites and seasons. The three varieties and one local cultivar of linseed were sown on June 1st, 10th, 20th, and 30th in both sites and seasons. The experiment was laid out in a randomized complete block design, with three replications. Yield attributes were collected and analyzed by using SAS software (9.4 versions). The yield components of dry biomass and seed yield were significantly influenced by the interaction effect of sowing and linseed varieties. The highest seed yields were obtained from June 1st and 10th sowing on Kuma, Berene, and Belay varieties at both sites and seasons. Minimum seed yield was recorded from local cultivars at late sowing dates. The improved varieties were better in responding to early sowing dates, which might imply their greater resource use efficiency than the local cultivar. In general, this study has shown that sowing linseed in early June at both sites was the optimum time, and future research might look into what happens if sowing a few days before June first.

Effect of Sowing Date on the Development of Lacy Phacelia (Phacelia Tanacetifolia Benth.).

Experiments with lacy phacelia (Phacelia tanacetifolia Benth.) were carried out in the period 2017-2021, during which the effect of sowing date on the stand development was assessed (height, coverage, accomplishment of individual growth stages, and weed infestation). It was demonstrated that the sowing date affects the stand growth and development. In earlier sowing dates, plants developed slower than in later sowing dates but reached a greater average height (926 mm). The lowest height (802 mm) was exhibited by plants from May (sowing 3). The third sowing date also showed the worst stand canopy closure and at BBCH 31, the stand canopy closure in Sowing 1, 2, and 3 was 82.3%, 77.8%, and 67%, respectively. The third sowing date was also the highest weed infestation. The effect of sowing date on yield and yield parameters was also monitored (weight of a thousand of grains and germinative capacity). Based on the measured data, it can be concluded that the influence on the weight of thousands of grains was minimal and in germinative capacity. Significant differences were recorded only in first year in which the germinative capacity of plants from the later sowing dates was reduced.

Sowing date affects soybean biological nitrogen fixation

AbstractIn many temperate soybean [Glycine max (L.) Merr.] production systems sowing date expands for several months. Early sowing dates commonly show maximum yields, but their consequences for crop N uptake and biological nitrogen fixation (BNF) are unknown. Our objective was to evaluate the role of sowing date, a major management variable defining soybean yield, on BNF. We hypothesized BNF is maximum at intermediate sowings because BNF is limited by low soil temperatures at early sowing dates and by high soil nitrate concentrations at later sowings. Four genotypes (maturity groups [MGs] IV and V) were tested over a 16‐wk sowing date period, and a N fertilizer treatment at sowing was added in all sowing date by genotype combinations (0 and 100 kg N ha–1). The N fertilization treatment helped to test sowing date effects independently of soil N availability. Seed yield and total N uptake were affected by sowing date and genotype, but not by the N treatment. Both seed yield and total N uptake followed similar quadratic responses, but MG V genotypes maximized yield and N uptake at the earliest sowing while MG IV cultivars maximized both traits at intermediate sowings. However, delaying sowing date always decreased the proportion of total aboveground N that came from BNF (average decline 0.22% d–1). Nitrogen fertilization reduced BNF by 15% across sowing dates and genotypes, with no yield effect. The linear decline in BNF with delayed sowing dates, instead of an optimum response, supports the concept that soil nitrates are the main driver of soybean BNF in this production system.

Importance of sowing date optimization for morphological properties and grain yield of maize inbred lines

This study aimed to determine the influence of sowing dates on morphological properties and grain yield. The experiment was conducted during 2018 (Y1) and 2019 (Y2) at one location in Serbia (Zemun Polje). Three inbred lines, produced at the Maize Research Institute (Serbia), were used as the material. Sowing was set in two terms, earlier 1 April (SD1) and optimal 20 April (SD2). Morphological properties of the cob were measured in the laboratory conditions: the ear weight (EW), the cob weight (CW), the cob length (CL), the cob thickness (CT), the 1000 kernel weight (SW), and the grain yield (GY). The sowing date significantly affected the morphological properties of the cob (p0,05). The interaction of factors also had a significant impact on the variability of traits. Three-way analysis of variance indicates that SD1Y1 treatment in combination with ZP1 and ZP3 inbred lines has a higher yield (6.28 t ha-1, 7.05 t ha-1). Further, the 1000-kernel weight in all three genotypes was higher in the SD1, ZP1 (324.35 g), ZP2 (329.78 g), and ZP3 (326.55 g). The earlier sowing date was also favourable for the cob weight. Meteorological conditions can be more or less stressful for field crops. Adverse weather conditions can be avoided or reduced by applying different sowing dates.