EFFECTS OF PLANT GROWTH REGULATORS AND DATES PLANTING ON SPRING MAIZE PRODUCTION UNDER AGRO-CLIMATIC CONDITIONS OF FAISALABAD, PAKISTAN
Keywords:heat stress, maize, plant growth regulators, sowing dates
Maize is a widely grown cereal crop worldwide, butthe heat stress and delayed sowing of maize are major constraints that result in declining the maize productivity.Therefore, the current study was designed to investigate the growth promoting effect of different growth regulators i.e., salicylic acid, methyl jasmonate, and humic acid at multiple sowing times in spring maize. Experiment was laid out in randomized complete block design having split-plot arrangement with three replications having plot size of 6m × 2.25m.The yield contributing agronomic parameters were recorded and analyzed statistically by using Fisher’s analysis of variance technique and treatment means were contrasted by Least significance difference having 5% probability test. Results revealed that early and delayed sowing of maize tended to decline the maize productivity and grain yield. Maximum yield and yield contributing traits were observed in S1 (recommended sowing, i.e., 20-02-2017). The plant growth regulators significantly influenced the productivity of maize and minimized heat stress. The interaction between sowing dates and plant growth regulators were also significant. Among plant growth regulators, the foliar application of methyl jasmonate resulted to produce maximum biological, grain yield, 1000-grain weight, and harvest index, which were 23.04, 36.12, 14.06 and 7.87%, respectively higher than the control.The study reported that delayed sowing of maize declined the production of maize due to the gradual rise of temperature in March and plant growth regulators had the potential to minimize the heat stress and productivity of maize.