Vol. 9, Issue 7, Part T (2025)

A field experiment was conducted during the rabi seasons of 2020-21 and 2021-22 at Punjab Agricultural University, Ludhiana, to evaluate the phenological development and growth dynamics of Indian mustard (Brassica juncea L.) genotypes under different sowing environments in a poplar-based agroforestry system. A split-plot design was employed with three replications, comprising two cropping systems (poplar+Indian mustard and Indian mustard sole crop) and four sowing times (1^st and 15^th October, 1^st and 15^th November) as main plots, and three Indian mustard genotypes (RCH 1, PHR 126, and PBR 357) as sub-plots. Results revealed that phenological stages and growth parameters were significantly influenced by sowing time and cropping system, while genotypic differences were more pronounced at later stages. Early sowing (1^st and 15^th October) resulted in faster emergence, earlier flowering, and a longer crop duration, leading to increased plant height, dry matter accumulation, and branching. In contrast, delayed sowing (especially on 15^th November) caused delayed development due to sub-optimal temperatures during early growth and excessive heat during reproductive stages. Mustard grown in open fields outperformed that grown in poplar alleys due to better light availability and favorable temperature conditions. Shading under poplar trees delayed phenological progression and reduced biomass accumulation. Among the genotypes, PBR 357 consistently exhibited superior growth performance. The findings suggest that early sowing, combined with the use of PBR 357 genotype, plays a pivotal role in enhancing the performance of mustard under poplar-based agroforestry system.