Exploring blackgram (Vigna mungo (L.) Hepper) growth potential: insights from germplasm evaluation and TFL1 gene expression profiling

Blackgram exhibits diverse growth habits influenced by both genetics and environment, ranging from determinate to indeterminate. Indeterminate growth offers yield advantages but presents challenges for mechanized harvesting. Our study focused on evaluating yield attributes, stem growth habit, and flowering duration in blackgram germplasm to understand genetic influences and optimize cultivation strategies, particularly addressing mechanized harvesting challenges. Additionally, we examined the expression of the TFL1 gene in selected genotypes. We assessed 100 blackgram genotypes across two consecutive spring sessions at different geographical locations, analysing 16 phenotypic traits. Most traits showed high broad-sense heritability and significant variability (P < 0.001) among the germplasm, with significant genotype-by-environment interactions observed. The GGE biplot pattern identified genotype IC530625 as less stable in maturity parameters, whereas genotype IC569464 consistently performed well across environments. Similarly, for yield attributes, four genotypes excelled in pods per plant and two in yield per plant, thus demonstrating stability and broad adaptability. These genotypes hold promise for genetic enhancement efforts in blackgram due to their adaptability and performance. Furthermore, expression research in indeterminate genotypes revealed increased TFL1 gene expression, suggesting its role in continuous floral initiation. This study underscores the potential of the TFL1 gene in modifying blackgram stem growth habits.