Energy dynamics and multicollinearity analysis of Brassica napus under different scenarios of crop establishment

Present investigation was conducted during 2023-24 and 2024-25 for energy budgeting and multicollinearity analysis of Brassica napus under different scenarios of crop establishment. The investigation included 5 scenarios of crop establishment viz., Scenario 1- sowing of crop by broadcasting of seed, Scenario 2- line sowing without thinning and gap filling (R-R: 45 cm), Scenario 3- line sowing including gap filling and thinning (R-R: 45 cm; P-P: 10 cm), Scenario 4- transplanting of 30 days old nursery (R-R: 45 cm; P-P: 10 cm) Scenario 5- sowing on 120 cm broad beds (90 cm top and 30 cm furrow) with pneumatic planter with 2 rows per bed with 4 replications. The results of the study showed significantly lesser number of primary and secondary branches in broadcasting technique as compared to rest of the scenarios. Scenario 3, scenario 4 and scenario 5 registered significantly higher number of siliquae per plant, seeds per siliqua, 1000 grain weight and grain yield of Brassica napus than broadcasting technique (scenario 1). Minimum energy input was recorded in pneumatic planting which was statistically at par with scenario 1 but significantly higher than rest of the treatments. Highest energy output (54168.75 MJ/ha) was registered by pneumatic planting which was statistically at par with transplanting technique (49475 MJ/ha) but significantly higher than line sowing and broadcasting technique. Highest energy use efficiency, specific energy and water productivity was observed in pneumatic planting. Pneumatic planting of mustard required minimum renewable energy input while non-renewable energy input was recorded in broadcasting technique (10573.77 MJ/ha) followed by pneumatic planting (11098.24 MJ/ha). Number of primary branches, secondary branches, number of siliquae per plant, seeds per siliqua, 1000 grain weight, energy use efficiency and energy productivity revealed a highly significant positive correlation with grain yield. Better grain yield, lesser energy requirement per unit of grain produced, less water energy input, high water productivity and high energy use efficiency in pneumatic planting makes this technology more sustainable and ecofriendly. Seed rate showed a negative direct effect and positive indirect effect on the grain yield. Number of siliquae and seeds per siliqua per plant depicted negative direct effect and strongly positive indirect effect on the grain yield. Energy use efficiency also had negative direct effect but strong positive indirect effect through number of secondary branches (1.204) and energy productivity (1.042). Energy productivity depicted a strong positive direct effect (1.032) on the grain yield.