Response of cotton to various levels of nitrogen and water applied to normal and paired sown cotton under drip irrigation in relation to check-basin

Field experiments were conducted for 2 years to investigate the effects of various levels of nitrogen (N) and methods of cotton planting on yield, agronomic efficiency of N (AEN) and water use efficiency (WUE) in cotton irrigated through surface drip irrigation at Bathinda situated in semi-arid region of northwest India. Three levels of N (100, 75 and 50% of recommended N, 75 kg ha⁻¹) were tested under drip irrigation in comparison to 75 kg of N ha⁻¹ in check-basin. The three methods of planting tried were; normal sowing of cotton with row to row spacing of 67.5 cm (NS), normal paired row sowing with row to row spacing of 35 and 100 cm alternately (NP) and dense paired row sowing with row to row spacing of 35 and 55 cm alternately resulting in total number rows and plants to be 1.5 times (DP) than NS and NP. In NS there was one lateral along each row, but in paired sowings there was one lateral between each pair of rows. Consequently the number of laterals and quantity of water applied was 50 and 75% in NP and DP, respectively, as compared with NS in which irrigation water applied was equivalent to check-basin.Drip irrigation under NS resulted in an increase of 258 and 453 kg ha⁻¹ seed cotton yield than check-basin during first and second year, respectively, when same quantity of water and N was applied. Drip irrigation under dense paired sowing (DP) in which the quantity of irrigation water applied was 75% as compared with NS, further increased the yield by 84 and 101 kg ha⁻¹ than NS during first and second year, respectively. Drip irrigation under NP, in which the quantity of water applied and number of laterals used were 50% as compared with drip under NS, resulted in a reduction in seed cotton yield of 257 and 112 kg ha⁻¹ than NS during first and second year, respectively. However, the yield obtained in NP under drip irrigation was equivalent to yield obtained in NS under check-basin during first year but 341 kg ha⁻¹ higher yield was obtained during second year. The decrease in N applied, irrespective of methods of planting, caused a significant decline in seed cotton yield during both the years. Water use efficiency (WUE) under drip irrigation increased from 1.648 to 1.847 and from 0.983 to 1.615 kg ha⁻¹ mm⁻¹ during first and second year, respectively, when the same quantity of N and water was applied. The WUE further increased to 2.125 and 1.788 kg ha⁻¹ mm⁻¹ under DP during first and second year, respectively. The agronomic efficiency of nitrogen was higher in drip than check-basin during both the years when equal N was applied. The WUE decreased with decrease in the rate of N applied under fertigation but reverse was true for AEN. It is evident that DP under drip irrigation resulted in higher seed cotton yield, WUE and AEN than NS and also saved 25% irrigation water as well as cost of laterals.     

Effect of cumulus cells and sperm concentration on fertilization and development of pig oocytes

Effect of sperm concentrations and cumulus cells (CCs) on porcine IVF was re‐evaluated using current improved IVM and IVC system. Our results showed that both CCs and sperm concentration had significant effect on penetration rate, frequency of polyspermy and embryonic development. The best IVF results were obtained with oocytes with CCs fertilized with 0.5 × 10⁵ sperm/ml. Such an IVP system works on both sow and gilt oocytes.     

Crop establishment method and irrigation schedule effect on water productivity,quality, economics and energetics of aerobic direct-seeded rice (<Emphasis Type="Italic">Oryza sativa</Emphasis> L.)

Rice is cultivated through transplanting of seedling in submerged field which is a cumbersome, labour intensive and water-guzzling practice. A field experiment was conducted to study the effect of crop establishment methods and irrigation schedules on water productivity, economics and energetics of aerobic direct-seeded rice at Punjab Agricultural University, Ludhiana, India, during Kharif 2012–2013. The experiment was laid out in split plot design, keeping combinations of two tillage system (no-tillage and conventional tillage) and two methods of sowing (uni-directional and bi-directional) in main plots and four irrigation schedule [(30, 45, 60 and 75 mm CPE (cumulative pan evaporation)] in sub plots. Aerobic direct-seeded rice sown after conventional tillage gave significantly higher grain yield than no-till with 15.4 % higher water expense efficiency. The energy gain and net monetary returns were 13.2 and 21.2 % higher in conventional sown crop than no-till, respectively. Bi-directional sowing resulted in 26.5 % higher grain yield than uni-directional with no effect on quality traits of grains. The net energy gain and net monetary returns were 26.5 thousands MJ/ha and 125.3 $/ha higher from bi-directional sown crop than uni-directional sown crop. Crop irrigated at 30 mm CPE schedule resulted in significantly higher grain yield than that irrigated at 45, 60 and 75 mm CPE. The energy gain, energy use efficiency and net returns were also maximum at 30 CPE schedule than at 45, 60 or 75 CPE. However, brown, milled and head rice recoveries were statistically at par between irrigation scheduling at 30 and 45 mm CPE but significantly better than 60 and 75 mm CPE. Bi-directional sowing with conventional tillage and irrigation at 30 CPE is an energy efficient and economical viable technique for direct-seeded rice.