Planting geometry and growth stage linked fertigation patterns: Impact on yield, nutrient uptake and water productivity of Chilli pepper in hot and sub-humid climate

Abstract

Optimal plant spacing and fertigation are the two management factors that influence yield, nutrient use efficiency and water productivity (WP) of any crop. In this context, a two year field experiment was conducted to standardize the planting geometry and fertigation practices for drip irrigated chilli in the hot-sub humid region of India. The study evaluated the effects of four planting geometries (sub-plots) with spacing of 75 × 50 (S1), 70 × 40 (S2), 50 × 40 (S3) and 30 × 40 (S4) cm in combination with three fertigation patterns having varying fertigation dose with increasing weeks after transplant (WAT) (main-plots), viz. uniform dose (FP1), higher dose during early reproductive stage (8th–13th WAT) (FP2) and higher dose during late reproductive stage (12th–18th WAT) (FP3) on chilli growth, yield and WP. Fertigation patterns and planting arrangements significantly influenced the number of fruits per plant, nitrogen recovery and nitrogen use efficiency (NUE). The fertigation pattern FP2 in combination with denser planting geometries (S3 and S4) had highest N recovery of 69.2 and 68.6%; NUE of 132.6 and 141.3 kg kg−1 N, respectively. The highest N, P and K uptake by chilli pepper was 105.9, 15.3 and 124 kg ha−1 in the denser plant populations (S4) with the treatment combinations of FP2-S4, FP3-S4 and FP3-S4, respectively. The chilli yield per plant decreased, while chilli yield per unit area increased gradually with increase in plant population. Highest chilli yield (14.5 t ha−1) and WP (31.1 kg ha−1 mm−1) was obtained when higher fertilizer dose was applied during early reproductive stage under S4 geometry (FP2-S4). Planting at 40 × 30 cm in triangular geometry (S4) with application of higher fertigation dose (FP2) during early reproductive stage is recommended for drip fertigation of chilli pepper in hot and sub-humid climate.