Quantitative and qualitative traits of sunflower genotypes as influenced by nitrogen application through fertigation

Fertigation is the application of dissolved fertilizer especially nitrogen through irrigation for correcting nutrient deficiencies of plants. A field study was conducted in Tandojam for two consecutive years in autumn 2018 and 2019. The experiment was replicated thrice in randomized complete block design. Different doses of nitrogen as broadcasting and fertigation (0, 75, 100, 125 kg N ha-1 in two and three equal splits given at sowing time, 1st, 2nd and 3rd irrigations, respectively) were applied to two sunflower genotypes (HO-1 and Hysun-39). Data analysis revealed nitrogen fertigation, genotypes and their interaction substantially (P≤0.05) affected growth and yield traits of sunflower. Greater seed yield (kg ha-1) and the oil content (%) were documented in N 10= 125 kg N ha-1: three splits (⅓ broadcasting at sowing time + fertigation- ⅓ at 1stand ⅓ at 3rd irrigation), followed by N8 = 125 kg N ha-1: two splits (½ broadcasting at sowing time + ½ as fertigation at 2nd irrigation). In between genotypes, higher seed yield (kg ha-1) and oil content (%) were recorded in HO-1 as compared to Hysun-39. As regards interactions, enhanced seed yield (kg ha-1) and oil content (%) were registered in the interaction of N 10 = 125 kg N ha-1: three splits (⅓ broadcast at sowing time + fertigation- ⅓ at 1st and ⅓ at 3rd irrigation) × HO-1. It was concluded from the results that nitrogen dose should be divided into three splits and applied at sowing time through broadcasting and fertigated at 1st and 2nd irrigation, respectively. Variety HO-1 should be preferred to obtain enhanced sunflower seed yield under Tandojam climatic conditions. (author)