Abstract

                                Grain yield in pea, as in other crops, is a complex character and is dependent on a number of component characters. Direct selection for this complex character is, therefore, often misleading. Hence some indirect methods such as determining the association between other less variable plant characters and yield are adapted. Selection pressure may then be exerted more easily on any of the characters which show close association with yield. Moreover, when a character is influenced by a series of other variables which are variously associated with one another, the estimation of simple correlation coefficients between any two of these does not give a true relationship between them. This suggests the necessity of working out partial correlation co- efficients. Previously. total correlations in pea were studied by Singh and Pratap (1968). In the present investigation, the same material was carried forward and partial correlation coefficients were obtained. Further, multiple correlation coefficients between grain yield per plant and the five important independent variables were worked out in order to ascertain the relative importance of these components in grain yield. Partial and multiple correla tions have also been studied by Bhatt et al. (1968) in soyabeans and by Sangha and by Sandhu (1970) in groundnut.

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