Pollination efficacy of honey bees (Apis mellifera L.) on field-grown triploid watermelon.

摘要

During the 1997, 1998, and 1999 growing seasons in South Carolina, studies were conducted to determine if the density of diploid watermelon plants in a commercial field of triploid watermelon has an affect on the quantity and quality of triploid fruit production, and to determine if the number of honey bee visits required to set fruit differ between triploid and diploid pistillate flowers.;For 1997, two extreme densities of diploid plants were tested in field-grown triploid watermelons. The ratios by row were 2:1 and 1:4 diploid to triploid plants, but the actual ratios by plants were 5:1 and 1:1.6 diploid to triploid plants. The experiment plots containing the 1:1.6 ratio of plants produced a significantly higher number of fruit per plant than did the 5:1 ratio of plants.;For 1998 and 1999, two pollen densities (1:2 and 1:3 ratios of diploid to triploid plants) were studied to determine what effect they would have on the total number of triploid fruit harvested, the number of triploid fruit produced per plant, the triploid fruit's weight, length, diameter, solid sugar content, and rind thickness. A total of 493 triploid fruit was harvested within sample areas within plots for both 1998 and 1999 from both experiment plots at the two locations. There was no significant difference between the 230 triploid fruit collected from the 1:3 ratio plots as compared to the 263 triploid fruit collected from the 1:2 ratio plots. Moreover, there was no significant difference between the grand means of the two treatments (1:2 vs. 1:3 ratio of diploid to triploid) for triploid fruit per plant and their weight, length, solid sugar content, and rind thickness.;During the summers of 1997, 1998, and 1999 a study was conducted to determine the minimum number of honey bee visits that are required to set fruit in a pistillate flower of triploid watermelon. Also, observations were made to document honey bee foraging activity and behavior on flowers of triploid watermelon. Over the course of this study, none of the observed 464 triploid pistillate flowers set fruit. Therefore, the required minimum number of honey bee visits necessary to produce fruit in a pistillate flower of triploid watermelon was not determined.