Agro meteorological indices influenced by different sowing dates, irrigation and fertilizer levels under late sown Indian mustard in western Haryana, India

A field experiments was carried out during 2018-19 and 2019-20 at Agronomy Research Farm, CCS HAU, Hisar. To compute the temperature based agrometeorological indices for Indian mustard sown under different growing environments along with Split plot design. Two sowing environments imposed through different sowing dates (2nd week of November and 4th week of November) and two irrigation levels (One irrigation at flowering stage and No post-sown irrigation) in main plots and four fertilizer levels (87.5%, 100%, 112.5% and 125% RDF) in subplots and replicated thrice. Crop sown during 2nd week of November had significantly higher agrometeorological indices (GDD, HTU, Tphoto, Tnycto and TIDR) values over 4th week of November sowing. Among irrigation levels, one irrigation performed better with respect to agrometeorological indices. Among fertilizer levels, application of 125% RDF exhibited significantly higher agrometeorological indices followed by 112.5%, 100% and 87.5% RDF. The seed yield and biological yield were highly significantly co-related with the accumulated GDD (0.95** and 0.95**), HTU (**0.83 and 0.83**) Tphoto (**0.96 and 0.96**), Tnycto (**0.953 and 0.951**) and TIDR (0.970** and 0.970**) clearly suggesting thereby the significant effect of these indices on the mustard crop. These indices can therefore very well used as indicators of crop performance, once these relationships are quantified and tested.