Selection of Yield-Associated Morphological and Biochemical Traits Using Correlation and Path Coefficient Analysis in Potato (Solanum tuberosum L.) in the Foothills of North-Western Himalayas

Abstract

The objective of the study was to assess the direct and indirect effects of 13 important morphological and biochemical traits on yield enhancement in 28 advanced breeding lines of potato (Solanum tuberosum L.) in the foothills of north-western Himalayas. Tuber yield was positively correlated with number of tubers per plant (r = 0.76), number of stems per plant (r = 0.53), number of leaves per plant (r = 0.43) and tuber weight (r = 0.37). Furthermore, tuber yield exhibited a significant negative correlation with days to maturity (r = − 0.39). Days to 50% emergence had a significant negative correlation with protein content (r = − 0.42). Path analysis revealed that the components of yield, number of tubers per plant and tuber weight, had high positive direct effects (0.876 and 0.618, respectively) on tuber yield, whereas the effects of other traits were low (≤ 0.128). Furthermore, tuber weight had an indirect negative effect on tuber yield through the number of tubers. Tuber size had a low correlation (0.19) with tuber yield because a positive indirect effect (0.451) through tuber weight was balanced by a negative indirect effect (− 0.254) through tuber number. The number of stems and number of leaves had positive indirect effects (0.377 and 0.377, respectively) on tuber yield through tuber numbers, whereas days to maturity had a negative indirect effect (− 0.298) through tuber numbers. There were virtually no indirect effects through the biochemical traits. The implications for potato breeding are discussed.