Impact of Boron Application Strategies on Broccoli ( Brassica Oleracea Var. italica ) Performance and Energy Budgeting in Boron Deficient Acid Soils of Indian Himalayas

Broccoli is a nutrient rich export-oriented vegetable. Boron (B) deficiency is one of the most limiting factors for achieving optimum broccoli agronomic productivity in acid soils. Therefore, in the present experiment we assessed the two-year productivity, micronutrients uptake, profitability and energy sustainability of broccoli crop grown on B deficient soils under different B application methods (foliar and soil + foliar), foliar application rates (0.1, 0.2, and 0.3% boric acid), and frequencies of foliar application (2 and 3 sprays of boric acid) along with control (without B application). The study was conducted for 2 years in a fixed-field plot using randomized complete block design with three replications. The results revealed that in comparison to control, the B application significantly enhanced the broccoli head yield and micronutrient uptake with better economic and energy efficiencies. Soil plus foliar B application produced 6.30% higher head yield compared to sole foliar application. The crop yield, economic indices, and energy dynamics were mainly influenced by foliar spray of boric acid at 0.3% applied at 30 & 45 DAT (days after transplanting) and head initiation growth stages. In general, the chemical fertilizers consumed the highest input energy (67.2%) followed by human labor (18.5%). Consequently, soil plus foliar method of B application and three foliar sprays of boric acid at 0.3% will be viable alternative to attain improved crop productivity and maximize the economic and energy efficiencies besides producing nutritionally (micronutrients) rich produce.