A field experiment was conducted during the rabi season of 2022–23 at the Research Farm, Division of Agronomy, Sher-e-Kashmir University of Agricultural Sciences and Technology of Jammu, to evaluate the effect of sowing dates, wheat (Triticum aestivum L.) varieties and plant growth regulators (PGRs) on yield and heat stress indices under sub-tropical conditions. The study involved three sowing dates, two wheat varieties and three PGR treatments in a split-split plot design. Results showed that sowing on 25 November recorded the highest canopy temperature depression (CTD), while 15 December sowing achieved the highest yield stability index (YSI). The variety DBW 303, particularly when treated with paclobutrazol, performed best in mitigating heat stress and achieving higher yields. Late sowing increased heat stress intensity and susceptibility, especially for variety JAUW 672 and untreated plots. It is concluded that, under the sub-tropical conditions of Jammu, sowing DBW 303 on 25 November with paclobutrazol application can enhance productivity and reduce the negative effects of heat stress.
S. Sidhant, K. Manpreet, S. B. Harsimran et al.· Plant Science Today· 0 citations
A field experiment was conducted during rabi 2022−23 at the Research Farm, Division of Agronomy, Sher-e-Kashmir University of Agricultural Sciences and Technology of Jammu. The soil of the experimental site was sandy clay loam, slightly alkaline with low organic carbon and available nitrogen (N), medium available phosphorus (P) and potassium (K). The experiment consisted of three sowing dates (viz., D1 : 25th November, D2: 15th December and D3: 5th January) in main plot, two wheat varieties (viz., V1: JAUW 672 and V2: DBW 303) in sub plot and two plant growth regulators (viz., T1: Control, T2: Bacillus subtilis at 5 g/kg seed + paclobutrazol at 50 ppm at 30 and 60 DAS and T3: B. subtilis at 5 g/kg seed + kinetin at 10 ppm applied at 30 and 60 DAS) in sub-sub plot replicated thrice in split-split plot design. The experimental results revealed that among different treatments 25th November sowing dates, variety DBW 303 and plant growth regulators paclobutrazol at 50 ppm along with B. subtilis at 5 g/kg seed, recorded significantly higher leaf area index (LAI) (3.91, 3.61 and 3.63), soil plant analysis development (SPAD) (42.48, 39.68 and 39.74), dry matter (1056.42 g/m2, 941.94 g/m2 and 949 g/m2), yield attributes {number of effective tillers/m2 (316.98, 298.72 and 291.50), number of grains/spike (42.58, 41.10 and 41.74), yield (4793.23 kg/ha, 4133.58 23 kg/ha and 4177.7923 kg/ha), net returns (121919.67 ₹/ha, 877203.52 ₹/ha and 102681.10 ₹/ha) and B:C ratio (3.93, 3.44 and 3.15)}. Also, the interaction has been found significant in the case of dates of sowing and varieties for the number of effective tillers per square metre, grain yield and straw yield. Hence, under sub-tropical conditions of Jammu, the wheat crop variety DBW 303 can be sown on 25th November along with the application of B. subtilis at 5 g/kg seed + paclobutrazol at 50 ppm for higher productivity and profitability.
S. Sidhant, K. Manpreet, T. Vipin et al.· Plant Science Today· 0 citations
