The present investigation was undertaken to study the change, if any, in the pattern of character association in grain yield and nine other characters over four different height groups and in the main group. For this purpose, 300 wheat genotypes of wheat constituted the main group in the present study. Genotypes in the main group, varied in-plant height from 38.80 cm to 133.40 cm. Based on certain range of plant height, four height groups were constructed involving 300 genotypes. It was observed that change in plant height affected the pattern of association between many traits relative to that in the main group. In many cases, the characters which showed significant associations in main group (e.g. 12 combinations of different traits: plant height and biological yield, plant height and 100-grain weight, flag leaf area and peduncle length, flag leaf area and tillers/plant, flag leaf area and grain yield, flag leaf area and grain weight/ear, peduncle length and 100-grain weight, biological yield and grain weight/plant, peduncle length and 100-grain weight, biological yield and grain weight/ear, grains/ear and flag leaf area, and 100-grain weight and harvest index) did show significant associations in one or two groups only, or non significant associations in all the four height groups (e.g.) plant height and flag leafarea, plant height and tillers/plant, plant height and grain yield, plant height and harvest index, peduncle length and tillers/plant, and peduncle length and grain weight/ear. In addition, several character combinations which exhibited non significant associations in main group (e.g. tillers/plant and 100-grain weight, and biological yield and harvest index), showed significant association between some characters in wheat as observed in main group cannot be regarded as of common occurrence, instead it depends on a certain plant height. For several combinations of characters, (such as tillers/plant and biological yield, tillers/plant and grain yield, biological yield and grain yield, grains/ear and grain weight/ear, grain weight/ear and 100-grain weight, and grain yield and harvest index) it was found that nature of association remains consistent over all the groups. Such consistent pattern suggests that change in plant height does not alter the ‘existence’ and ‘direction’ of correlation between some specific characters. Such associations may be regarded as of "common occurrence" in wheat crop are not dependent on plant height.
Wheat, quantitative traits, correlation, height groups
