2019 Volume 18 Issue 3 Pages 207-213
Differences in productivity, dry matter production, and phenotypes among eight cultivars of Japanese sweet pepper (Capsicum annuum L.) were examined to clarify factors that contribute to productivity under non-pinching cultivation with two main stems. Based on the fruit fresh weight, ‘Tosa P red’ and ‘Tosahime’ were classified as high-yield cultivars, and ‘Sarara’ and ‘Green 800 gou’ were classified as low-yield cultivars. The high-yield cultivars showed no difference or an increase in the number of fruits, and a mean fruit weight intermediate between the two low-yield cultivars. There was no significant difference in the ratio of dry matter partitioning to fruits among the cultivars, and the partitioning ratio was not significantly correlated with the fruit yield in terms of fresh or dry weights. On the other hand, the total dry matter production (fruits, stems, leaves and pruned shoot) of the high-yield cultivars was significantly (p < 0.05) larger than that of the low-yield cultivars, and there was a significant correlation between the total dry matter production and fruit yield in terms of fresh (p < 0.01) and dry (p < 0.01) weights. The phenotypic analysis indicated that the main axis diameter and main stem node number at 81, 123 and 158 days after sowing (the end of cultivation) were not significantly correlated with the total fruit fresh weight, but showed a high positive correlation with the total dry matter production at the end of cultivation. These results indicate that the fruit yield can be raised by increasing the total dry matter production more effectively than the ratio of dry matter partitioning to fruits.
