Abstract
Extremely early cultivars of turnip, Brassica rapa L., with a rapid growth in younger stages to allow harvesting about 50 days after sowing, are in great demand in Jpan. A diallel-cross experiment was conducted to find to what extend the heterosis could participate in the early growth of turni, ps. Seven varieties differing from each other with regard to root size were used to yield 42 cross-combinations including reciprocals. Those forty-two F1 hybrids and seven parental lines were planted in randomized blocks with two replications, and a diallel-cross analysis was performed. Plants were harvested 50 days after sowing, and measurement was made on diameter and length of plump root, diameter of tap root, and leaf length. The diameter of plump root at 50 days is taken as an indicator of the degree of earliness.
