Maximizing Growth and Yield Of Black Seed (Nigella Sativa L) through Optimized Phosphorus and Boron Levels

Improper nutrient management cause yield reduction in black seed yield and quality. Therefore, a field trial was executed in the growing season 2022-23 at The University of Agriculture Peshawar to inspect the effects of different phosphorus (P) and boron (B) levels on black seed (Nigella sativa L.). The experiment used a randomized complete block design with a split-plot arrangement, replicated thrice. The study examined four P levels (0, 15, 30, and 45 kg/ha) and four B levels (0, 1, 2, and 3 mg/L) on various growth and yield parameters of black seed. Plots treated with 45 kg/ha of P exhibited the taller plants (37.00 cm), more branches (16.60), larger leaf area (128.30 cm²), longest roots (10.00 cm), highest levels of chlorophyll a, b and carotenoids (1.80, 1.30 and 1.10 mg/g) compared to control. 45 kg/ha P also produced maximum flowers/plant (23.10), capsules/plant (22.80), seeds/plant (1325.50), thousand-seed weight (2.80 g), and the maximum seed yield (255.30 kg/ha). Similarly, plants treated with 3 mg/L of B had the tallest plants (33.60 cm), more branches (15.90), leaf area (128.20 cm²), longest roots (8.70 cm), chlorophyll a, b and carotenoids (1.40, 1.20 and 1.00 mg/g), more flowers/plant (21.30), capsules/plant (20.70), seeds/capsule (58.70), seeds/plant (1193.60), the heaviest thousand-seed weight (2.70 g) and the maximum seed yield (255.30 kg/ha). Moreover, significant association was prominent between growth and yield components with seed yield of black seed under different treatments. Therefore, it was concluded that the best growth and yield for black seed were observed with fertilization of 45 kg/ha of P and 3 mg/L of B.