Nitrogen (N) fertilization plays a pivotal role in physiomorphological attributes and yield formation of field-grown cotton (Gossypium hirsutumL.), but little is known of its interaction with irrigation levels. Therefore, this study was conducted with an objective of evaluating the impact of irrigation and nitrogen levels on growth attributes and nitrogen use efficiency ofBtcotton (Gossypiumspp.) in the hot arid region. The experiment consisted of a factorial arrangement of three irrigation levels (200, 400, and 600 mm) and four nitrogen rates (0, 75, 150, and 225 kg ha^–1) in a split-plot design with three replications. Nitrogen fertilization and irrigation levels influenced cotton growth attributes and yield. The highest leaf area index, dry matter accumulation, crop growth rate, and relative growth rate were achieved at 225 kg N ha^–1and irrigation level 600 mm as compared to other experimental treatments. Similarly, nitrogen uptake and content by seed, lint, and stalk and total nitrogen uptake recorded maximum at 225 kg N ha^–1and irrigation level 600 mm. Interestingly, the treatment of 600 mm of irrigation and 150 kg N ha^–1displayed significant increase in nitrogen use efficiency indices such as agronomic efficiency of nitrogen (AEN) and recovery efficiency of nitrogen (REN), while partial factor productivity of nitrogen (PFPN) and internal nitrogen use efficiency (iNUE) were significantly higher with application of 600 mm of irrigation and nitrogen application rate of 75 kg ha^–1. Application of 600 mm of irrigation along with 225 kg N ha^–1resulted in significant increase in gross return, net return, and B:C ratio than any other treatment combinations. So, application of 600 mm of irrigation along with 225 kg N ha^–1could be recommended for achieving higher growth and yield, as well as profitability ofBtcotton under hot arid region and similar agroecologies.

Optimal nutrient management is critical for optimizing flowering, yield, quality and improving soil health. A key approach for making chrysanthemum crop cultivation profitable is balanced fertigation at the right time. This is possible by fertigation through drip. The present study was designed in 2019–2021 at a model floriculture center, Pantnagar, to investigate the response of split application of NPK through drip fertigation on flowering attributes, yield, biochemical activity and soil nutrient status of chrysanthemum. Plants received application of NPK with five treatment combinations: T1-NPK @ 100:150:100 kg/ha/year, T2-NPK @ 100:150:100 kg/ha/year, T3-NPK @ 100:150:100 kg/ha/year, T4-NPK @ 75:112.5:75 kg/ha/year and T5-NPK @ 75:112.5:75 kg/ha/year at vegetative, bud and flowering stages. The results reveal that the plants treated with treatment T3 (NPK @ 100:150:100 kg/ha/year) exhibited maximum increases in floral bud diameter (31.45%), number of inflorescences per branch (24.44%), diameter of inflorescence (15.32–28.44%), weight of inflorescence (24.30%), stem diameter, inflorescence stem length, number of inflorescences per plant (6.16%), number of inflorescences per hectare (53.46%), chlorophyll a content, chlorophyll b content, total chlorophyll content (40.20%), carotene content of inflorescence (69.56%), organic carbon (1.22-fold), available nitrogen content (7.46%), available phosphorus and available potassium (1.14-fold) compared to the control. Conclusively, the results suggest that split application of NPK through drip fertigation may improve the inflorescence attributes, yield, biochemical activity and soil nutrient status of chrysanthemum.

Effect of water and nitrogen levels on yield attributes, water productivity and economics of cluster bean (Cyamopsis tetragonoloba) in hot arid region

An experiment was conducted at research farm, Agricultural research sub-station, Hanumangarh, a unit of Swami Keshwanand Rajasthan Agricultural University, Bikaner during Kharif season, 2016 to study the effect of water and nitrogen application rates on yield attributes, yield and water productivity of cotton (Gossypium sp.). Cotton variety Sri ram 6588 BG II was planted using 3 levels of irrigation (200, 400 and 600 mm) and 4 level of nitrogen (0, 75, 150 and 225 kg ha⁻¹) in split plot design with three replications. The water and nitrogen application rates had significant influence on yield attribute, yield and water productivity of cotton. The results indicated that the irrigation level 400 mm recorded significantly higher number of bolls per plant (37.08), boll weight (3.83 g), seed cotton yield (2568 kg ha⁻¹), lint yield (734 kg ha⁻¹) and seed yield (1834 kg ha⁻¹) but was at par with irrigation level 600 mm. The highest stalk yield (4947 kg ha⁻¹), biological yield (7599 kg ha⁻¹) and seed index (9.21) were observed with irrigation level 600 mm. However, highest water productivity (0.405 kg m⁻³) was observed with irrigation level 200 mm. The maximum number of bolls per plant (41.78), stalk yield (4745 kg ha⁻¹), biological yield (7462 kg ha⁻¹) and water productivity (0.392 kg m⁻³) were found with nitrogen application rate 150 kg ha⁻¹. The highest boll weight (4.05), seed index (8.47), seed cotton yield (2813 kg ha⁻¹), seed yield (803 kg ha⁻¹) and lint yield (2010 kg ha⁻¹) were observed with nitrogen level 225 kg ha⁻¹. The irrigation and nitrogen level had no significant effect on plant population at harvest. Irrigation along with nitrogen levels significantly influenced the yield attributes, yields and water productivity of Bt cotton. The combined application of irrigation level 600 mm and N @ 225 kg ha⁻¹ resulted in significantly higher number of bolls per plant, seed cotton yield, stalk yield and total water productivity in comparison to irrigation @ 200 mm and N @ 0 kg ha⁻¹ (control).

Background: Clusterbean (Cyamopsis tetragonoloba L.) is important commercial crop which belongs to family Leguminosae and has capacity to fix the atmospheric nitrogen. The nitrogen fixed by the legume crop is not enough to meet the demand of short duration crop like clusterbean. Besides, the experimental site falls under arid region where drought stress and poor distribution of rain during the crop growing cycle is common which affects the crop growth and productivity. Drawing on these insights, the study was planned to assess the performance of cluster bean with objectives to quantify water balance and to calculate suitable levels of irrigation and nitrogen. Methods: The experiment was conducted at research farm, Agricultural research sub-station, Hanumangarh, Swami Keshwanand Rajasthan Agricultural University, Bikaner during Kharif, 2016. Cluster bean variety RGC-1055 with seed rate of 16 kg ha-1 was planted with 3 levels of irrigation (100, 200 and 300 mm) and 4 levels of nitrogen (0, 20, 40 and 60 kg ha-1) and analyzed in split plot design with three replications. Result: Results showed by that the irrigation and nitrogen application rates significantly influenced the growth parameters, yield, nitrogen content and uptake by cluster bean. Irrigation level 200 mm significantly increased leaf area index at 60 DAS (2.62), dry matter accumulation (DMA) at 60 DAS and harvest (16.51 and 42.62 g plant-1), crop growth rate at 30-60 DAS and at harvest (0.36 and 0.62 g m-2 day-1), relative growth rate at 60- at harvest (1.59 g g-1 day-1), grain yield (1624 kg ha-1), straw yield (3645 kg ha-1) and biological yield (5270 kg ha-1) over irrigation level 100 mm, but statistically at par with irrigation level 300 mm. However, leaf area index at harvest (1.24) was highest at 300 mm irrigation level. Nitrogen level at 40 kg ha-1 significantly increased leaf area index at 30, 60 DAS and at harvest (0.19, 2.65 and 1.16), dry matter accumulation at 60 DAS and at harvest (19.62 and 49.58 g plant-1), crop growth rate at 30-60 DAS and 60- harvest (0.46 and 0.71 g m-2 day-1), relative growth rate at 30-60 DAS and 60-harvest (1.26 and 1.66 g g-1 day-1), grain yield (1668 kg ha-1), straw yield (3696 kg ha-1) and biological yield (5364 kg ha-1) over control. The highest nitrogen content and uptake in grain and straw was obtained with irrigation level at 300 mm and nitrogen level @ 60 kg ha-1.

Background: Rice is most important staple meal for more than half of the world’s population. The conventional method of rice production uses a lot of water, requires a lot of labor and has a negative impact on soil and environmental health. Besides, unbalanced nutrient supply leads to low growth and development of plant, soil deterioration and poor environmental health. Methods: The field experiment was conducted with rice variety PR-121 using 4 establishment methods (transplanting, system of rice intensification, direct seeded rice and wet-direct seeded rice) and 5 nutrient management practices (100% RDF, 75% RDF+FYM (equiv. to 25% N), 150% RDF, RDF (LCC based N application) and RDF+5 t FYM) in split plot design with three replication. Result: Results revealed that the highest value of plant height was recorded under transplanting method while the maximum value of number of tillers m-2, dry matter accumulation crop and relative growth rate was found under direct seeded method of rice establishment over other establishment methods at all the stages of crop growth during both the years of study. Application of 150% RDF recorded the highest value of plant height, number of tillers m-2, dry matter accumulation, crop growth rate and relative growth rate on most of the crop growth stages during both the years of study compared to remaining nutrient management practices but found statistically on par with application of RDF+5 t FYM.