ANALYSIS OF FRUIT YIELD AND RELATED FACTORS IN A DIALLEL OF SEVEN INBRED STRAWBERRY CLONES

Abstract

A diallel of seven inbred clones of the domestic strawberry was evaluated for 5 variables and was compared with the standard cultivar Redcoat. For fruit yield, berry size, date of mid-harvest, and area covered by the clone, the Redcoat values were close to the mean of the diallel. Unexpectedly, all seedling crosses produced more than twice as many runners as did Redcoat.The additive component of variance was only 3.2 per cent for yield, but was 50.5, 83.0, 27.6, and 10.9 per cent for berry weight, mean date of harvest, runner number per clone, and area covered per clone respectively. Total fruit yield was significantly influenced by all of the other four variables, but the relationship was highly variable and did not present any consistent pattern. A cautious interpretation of results is required because of common parentage and inbreeding in the parental lines.The results of this study are in general agreement with similar studies at North Carolina and Ottawa, but all three of these studies gave quite different results from one in California using a parent-offspring regression method of analysis. It is suggested that the different methods of measuring genetic parameters may be as important in resolving this discrepancy as methods of culture, range of cultivars and climatic factors, which have been previously suggested.