Wheat response to foliar application of salicylic acid at different sowing dates

ABSTRACT Temperature rise in March induces forced maturity in wheat (Triticum aestivum L.), which generally reduces the grain-filling period under North Indian conditions. A field experiment was conducted at the Punjab Agricultural University, Ludhiana, India, during 2015–16 and 2016–17 to evaluate the effect of salicylic acid on plant growth, physiological parameters, and grain yield of two wheat cultivars sown at different dates. A split-split-plot design was used, with sowing dates (November 5, November 20, and December 5) as main plots, wheat cultivars (WH1105, PBW677) as sub-plots, and salicylic acid foliar treatments (control, water spray, salicylic acid 75 and 100 mg l−1) as sub-sub plots. The highest tiller count, atLEAF-chlorophyll index, pollen viability, number of grains ear−1, 1000-grain weight, biological and grain yield were recorded for the November 5 sowing date. Salicylic acid foliar application at 75 and 100 mg l−1 increased the grain-filling period, improved the normalized difference vegetative index (NDVI), pollen viability, number of grains ear−1, proline content, 1000-grain weight, and grain yield. We concluded that wheat cultivars WH1105 and PBW677 can be grown successfully by sowing early (November 5) and that foliar application of salicylic acid at 75 mg l−1 can improve the wheat grain yield under north Indian conditions.