Effect of projected climate scenarios on the yields of potato crop and agronomic adaptation options as evaluated by crop growth model

Potato is the most important non-cereal crop in the world and the most prominent winter season crop in India. Growth and yield of potato crop is very much sensitive to higher temperatures and the moisture stress. Hence, the anticipated increase of temperature due to global warming and climatic variability will have anadverse impact on potato production. Keeping this in view, a research work was carried out with the objectives to assess the impact of climate change on potato production and evaluating agronomic adaptation options through a crop growth simulation model (CGSM). Field experiments were carried out to prepare the minimum dataset for calibration and validation of one CGSM, namely InfoCrop. After validation, the model was used to predict the future tuber yield of ten selected stations situated under different agroclimatic regions of the State. In the future scenario 2050, the simulated yield for mid November planted crop likely to be about 11% less than the present level of mean yield. If the crop is planted in December, the percentage of yield reduction may be around 25%.The projected yield reduction, for the stations of higher latitude, is found to be negligible. Three possible agronomic adaptation options, viz., adjustment of date of planting, increase of seed rate and varying sprout length of seed tubers, have been tried as adaptation strategies to combat the adverse effects of climate change. It is concluded that the mid-November planting and longer sprout length will be the best adaptation option. However, the enhanced seed rate is not a viable adaptation option.

Enhancement of Soybean (Glycine max L.) Productivity through Sowing Methods and Seed Rates in Telangana State

Background: With the unparalleled growth in area and production, soybean has established itself as a leading oilseed crop of India. The crop is mainly grown under rainfed conditions, and the distribution of rainfall plays an important role in yield realization. The changed landform management with broad-bed furrow seed drill is gaining popularity as the system helps in in situ moisture conservation and draining out excess rainwater. A field experiment was conducted at Regional Sugarcane and Rice Research Station, Rudrur. The yield advantage by adoption of broad-bed and furrow (BBF) method over flat bed was 7.06%. Seed rate of 50 kg ha-1 recorded significantly higher mean seed yield of 2804 kg ha-1 over 75, 38, 20 kg ha-1. The total benefit from adoption of BBF method recorded net returns of ₹ 53,233 ha-1 and B:C ratio of 2.58 over flatbed planting. Seed rate of 50 kg seed ha-1 recorded the highest net returns and B:C ratio this was followed by 75 kg ha-1 seed rate. Methods: A field experiment was conducted for three years (2017-19) at Regional Sugarcane and Rice Research Station, Rudrur, situated at an altitude of 286.3 m above mean sea level at 18°49’41" N latitude and 78°56’ 45" E longitude. Indeterminate variety of soybean ASB 22 was selected. The experimental plots (6m × 6m= 36m2) were laid out with split plot design with three replications. Main plot treatments were methods of planting: M1- Flat bed, M2- Broad bed and Furrow, and sub plot treatments were : seed rates; S1- 75 kg ha-1 (30 × 10 cm), S2- 50 kg ha-1 (30 × 15 cm), S3- 38 kg ha-1 (30 × 20 cm), S4- 20 kg ha-1 (30 × 30 cm). Result: The grain yields, water productivity, harvest index and economics of soybeans under BBF method of planting (in-situ water conservation) and flatbed practices were studied. BBF method increased seasonal soil water storage by 5.37%, 5.78% and 6.20% respectively compared with flatbed planting for 2017, 2018 and 2019 respectively. Seed rate of 50 kg ha-1 recorded significantly higher mean seed yield of 2804 kg ha-1 over 75, 38, 20 kg ha-1. The yield advantage by adopting seed rate of 50 kg ha-1 was 16.08%, 56.02% and 67.6% over 75, 38 and 20 kg ha-1 respectively. The total benefit from adoption of BBF method recorded net returns of ₹ 53,233 ha-1 and B:C ratio of 2.58 over flatbed planting. Seed rate of 50 kg ha-1 recorded the highest net returns and B:C ratio this was followed by 75 kg ha-1. Broad bed and furrow method of planting and optimum seed rate in soybean will enhance the soybean productivity.

Allelopathic Allelopathic impact of sorghum on weed management, yield and quality of maize under different seed rates

A field study was carried out to estimate the allelopathic potential of sorghum immature and mature plant extracts under various seed rates on weeds density and yield of maize cultivar Dadu Maize-I. The experiment contained of different weed control practices i.e., control (No weeding), various levels of sorghum immature and mature plant extracts, herbicides and hand weeding under various seed rates (20, 25, 30 & 35 kg per ha). The analysis of variance showed that various weed control practices demonstrated substantial decrease in weeds and caused increase in kernel yield over control. The application of sorghum immature extract @ 15 L per ha in combination with herbicide (Mesotrione Atrazine) @ 1.0 L per ha decreased effectively weed density (m-2) and dry biomass (g m-2) and resultantly produced superior growth and yield traits particularly kernel yield (t per ha) of maize. Sorghum mature plant extract @ 15 L per ha in integration with herbicide (Mesotrione Atrazine) @ 1.0 L per ha ranked 2nd in effectiveness of controlling weeds as well as increasing maize kernel yield (t per ha). As much as effect of seed rates is concerned, the least weed density (m-2) and greatest kernel yield (t per ha) were noticed in seed rate 35 kg per ha but optimal kernel yield (t per ha) was record in seed rate 30 kg per ha. Hence, the results suggested that combination of plant extracts and herbicide at reduced doses controlled weeds efficiently and optimum enhancement in kernel yield of maize was noticed at seed rate 30 kg per ha.

Influence of Different Seed Rates on the Growth and Yield Characteristics of Wheat Crop (Triticum aestivum L.): Case Study of Takhar Province, Afghanistan

The purpose of this study was to determine the effect of seed rate on the growth and yield attributes of the wheat crop (Triticum aestivum L.) variety Mazar-99 under the agro-climatic conditions of Takhar province, Afghanistan. The experiment was implemented at the research farm of Agriculture Faculty of Takhar University in winter seasons of 2018-2019 with the specific objective of finding out the effect of five seeding rates as the treatment on growth and yield parameters of Mazar-99 variety of wheat. Randomized Complete Block Design (RCBD) was selected as an experiment design with 4 replications and 5 seeding rates viz. 80, 100, 120, 140 and 160 kg/ha made up treatments. Data on growth and yield parameters were collected and analyzed using Analysis of Variance (ANOVA) for Randomized Complete Block Design (RCBD). The result obtained from the current study reveal that all growth and yield characters were remarkably affected by seeding rate and seed rate of 100 kg per hectare of wheat variety Mazar-99 performed better with respect to different growth and yield parameters such as spike length, number of tillers, number of spike at each plant, leaf area, a total of spikelets per spike and stem girth, grain number/spike, the weight of spike, the weight of grain per spike, grain crop yield, straw crop weight, 1000-grain weight, and biological yield. Whereas 80 and 120 kg/ha were the second-best seeding rates after the 100 kg/ha. However, 160 kg/ha seed rate showed only superiority in plant height, but 140 kg/ha did not show any special superiority in any growth and yield characteristic evaluated in Takhar agro-climatic condition. Thus, a seeding rate of 100 kg per hectare could be recommended to the farmers for better wheat production in Takhar agro-climatic situation in North-Eastern Afghanistan.

DESIGN AND EXPERIMENT OF A NEW ROTARY COATING MACHINE BASED ON LabVIEW

In view of the problems of long coating time, complicated manual operation, high multi-seed rate of coated seeds, low qualified rate, and low degree of automation of control equipment in traditional rotary coating machine, a new type of rotary coating machine was designed while using LabVIEW with a complete electric control system, which can effectively improve the speed and quality of coating. The system uses single-chip microcomputer as the lower computer, LabVIEW as the upper computer, and uses programming electronic control technology to set seed coating parameters in advance, precisely control each part and achieve precise supply. Batch supply of powder and liquid greatly improves the automation and intelligence of the operating system, improves the coating efficiency, reduces the multi-seed rate and the seedless rate, and increases the coating pass rate. In order to improve the coating quality and the supply accuracy of the coating machine, the error analysis and calibration test of the seed supply system, powder supply system and liquid supply system were carried out. After the test verification, the supply error was controlled within 2% to meet the demand for precise supply. The test results show that the pass rate of the seeds coated by the new rotary coating machine is increased by 15% to 20% compared with the seeds coated by the traditional manual coating.

Oilseed Rape Yield Performance in the Clearfield® System under Varying Management Intensities

Oilseed rape production is under pressure due to a limited availability of herbicides. Therefore, the performance in terms of management intensity (MI) and herbicide strategy (HS) and the involved yield formation was evaluated in a two-year Clearfield® oilseed rape field experiment. Furthermore, weed density and weed composition were also investigated. The variants of MI were standard sowing density (StS; seed rate: 50 seeds m−2, primary tillage: plow, row width: 12 cm), reduced sowing density (RD; seed rate: 25 seeds m−2, primary tillage: plow, row width: 50 cm), and strip-till (ST; seed rate: 25 seeds m−2, primary tillage: strip tillage, row width: 50 cm). The variants of HS were preemergence strategy (PES; application of dimethachlor, napropamide, clomazone in preemergence and application of prapaquizafop in postemergence) and Clearfield® strategy (CLS; application of imazamox, quinmerac in preemergence, no postemergence herbicide application). In the first year of the trial, there were no interactions between the factors in terms of grain yield. Grain yield in StS was 3.85 t and 5.2% significantly lower than in ST, and the value of RD was not significantly different from StS and ST. Grain yield in CLS was 3.7 t and 2.7% lower than in PES. In the second year of the trial, the grain yield in ST CLS was significantly lower, and there were no significant differences between the other variants. Higher weed emergence was observed in CLS RD (2.7 to 4 times higher weed density compared to PES RD) and CLS ST (2.8 to 4.5 times higher weed density compared to PES ST). No significant differences existed between StS PES and StS CLS in both trial years. The Clearfield® system offers significant advantages in the control of cruciferous weeds. Although these did not occur on the trial fields, the Clearfield® system in this study showed to be an alternative to the more common pre-emergence system, especially with regard to the parameter grain yield.

Phenotypic correlation and regression of hydroponics maize fodder as influenced by seed rate, nutrient sources and spray schedule

The experiments were carried out at AICRP on Dry Land Agriculture, University of Agricultural Science, GKVK, Bengaluru to study the “Phenotypic correlation and regression of hydroponics maize fodder as influenced by seed rate, nutrient sources and spray schedule” during 2017-2018. The results of revealed significantly positive correlation between fodder yield per kg seed and yield parameter like total fresh weight of fodder per kg seed (r=0.95**), total dry weight per kg of seed (r=0.86*), growth parameters like shoot length (r= 0.90**), root length (r=0.85*) and seedling vigour (r=0.84*), physiological parameters like water use efficiency (r=0.86*), relative water content (r=0.91*) and SPAD (r=0.92**). With respect to nutrition study correlation coefficients of traits with fodder yield revealed positive correlation growth components like shoot length (r=0.90**), root length (r=0.74**), seedling vigour (r=0.86**) and dry matter accumulation (0.97**), yield parameters like Total fresh weight of fodder (r=0.96**), individual fresh weight of plant (r=0.95**) and individual dry weight of plant (r=0.97**), physiological parameters like SPAD (r=0.78**) and WUE (r=1.00**), quality parameters like nitrogen content, crude protein, crude fibre and total carbohydrates (r=0.927**, 0.927**, 0.770* and 0.905**, respectively). The study revealed significantly higher fodder yield with two combined sprays of urea and MOP each @ 1 per cent at 3rd and 10th Days after sowing (DAS) with 2.5 kg m-2 under hydroponic conditions.

Effect of Nitrogen Fertilizer and Rate of Seeds on Some Growth Criteria and Dry Matter Production of Barley (Hordeum Vulgare L.)

A field experiment was carried out at the Second Agricultural Research and Experiments Station of the College of Agriculture/University of Al-Muthanna in Al Bandar region, during the winter season (2019-2020), in order to know the effect of nitrogen fertilization and seed rate on the production of dry matter for barley crop, and the experiment was applied according to the arrangement of the split plates. According to the design of randomized complete blocks with three replications, the number of experimental units was 120 units. The experiment included the secondary factor of five seed quantities (40, 60, 80, 100 and 120 kg ha−1) and the main factor included 4 levels of nitrogen fertilizer (0, 50, 100 and 150 kg ha−1). The results showed that the rate of seed were significantly superior in most of the growth characteristics and dry matter of the barley crop, where the rate of seeds 80 kg ha-1 outperformed in the characteristics of plant height, dry weight of the stem, dry weight of leaves, dry weight of ears and dry weight of the plant, where their averages were (96.64 cm, 10.34 g, 7.20 g, 4.78 g and 22.3 g) respectively, while the level of 120 kg ha−1 seed rate outperformed in increasing the area of the flag leaf, which amounted to 23.67 cm 2, and the lowest seed level 40 kg ha-1 gave an increase in the length of the spike, which reached 7.06 cm. As for nitrogen fertilizer levels, the levels were significantly higher in all studied traits, where the amount of fertilizer 100 kg ha−1 outperformed in all studied traits, plant height (100.20 cm) and area leaf flag (24.38 cm 2), the number of tillers (8.38 tillers Plant−1, the length of the spike (6.92 cm), the dry weight of the stem (10.84 g), the leaves (7.29 g), the spikes (5.38 g), and the dry weight of the whole plant (23.51 g). As for the interaction between the rate of seed and nitrogen fertilization, the combination (80 kg ha−1 seed * 100 kg ha−1 nitrogen) outperformed and gave the highest averages for most of the studied traits. And the weight of the full bat where their averages were (13.20, 10.51, 7.37 and 31.07 g) respectively.