Association studies in linseed (Linum usitatissimum L.) under different production systems over locations

The present experiment was conducted to determine the important yield components and their association with one another and with yield. The experiment was laid out under two production systems over four different locations in the mid-hills of the North-western Himalayas. Correlation studies indicated a strong positive correlation for seed yield with harvest index (EI 0.668**; EII 0.472**) and biological yield (EI 0.362; EII 0.532) in both the production systems. Whereas, a non-significant positive correlation was observed for the number of primary branches (EI 0.103; EII 0.122) and the number of secondary branches (EI 0.033; EII 0.160) in both production systems. Whereas, among other traits highly significant correlation was observed for days to 50% flowering with days to 75% maturity in both production systems (EI 0.837**; EII 0.781**) followed by plant height (EI- 0.626**; EII- 0.562**) and technical plant height (EI 0.617**; EII 0.598**). Path coefficient analysis indicated that only biological yield (EI 0.70348; EII 0.60597) and harvest index (EI 0.90210; EII 0.53283) showed a highly significant direct effect with seed yield in both production systems. This showed that selection for biological yield and harvest index would have a direct positive effect in the improvement of grain yield and are the most important determinants of yield in linseed. However, traits such as number of primary branches, number of secondary branches and 1000 seed weight should also be given significant importance since these traits also showed a positive correlation with seed yield but with indirect effects via biological yield and harvest index in EI and EII, respectively.