Heritability, correlation and path coefficient of downy mildew, yield and yield components in cucumber

Abstract

The relativity of the Downy Mildew (45 and 60 days after transplanting) for 109 lines in both yield and yield components of cucumber from July 2012 to March 2013 was studied at Agricultural Technology Research Institute of Rajamangala University of Technology, Lanna Lampang. It is discovered that the correlation coefficient of downy mildew levels at 45 and 60 days after transplanting correlated well at 0.78 (r = 0.73). Furthermore, it is also found out that the correlation coefficient of downy mildew levels at 60 days after transplanting was negatively correlated with fresh yield per rai at 0.58 (r = -0.58). When considering from the path coefficient, it is found that the number of fruits per plant had high total effects and direct influence on yields per rai (0.84 and 0.70, respectively). Whereas the downy mildew levels at 60 days after transplanting had negative total effects at -0.58 indirectly with number of fruits per plant at -0.27. Thus the cucumber with high downy mildew at 60 days after transplanting will lead to 58 percent of yield reduction that it will reduce the number of fruits per plant which caused yields reduction.