Effects of Grafting, Organic Fertilization, and Plant-growth-promoting Rhizobacteria on Specialty MelonProduction

摘要

Grafting with selected rootstocks and the use of plant-growth-promoting rhizobacteria (PGPR) have been shown to improve plant resistance/tolerance to biotic and abiotic stresses and enhance plant growth and development. The objective of this study wasto examine the effects of the application of grafting and PGPR on fruit yield and root-knot nematode infestation in specialty melon production under organic and conventional fertilization. 'Tasty Bites' musk- _ melon (Cucumis melo), a commercial hybridcultivar developed from the cross between Charentais and Ananas melons was grafted onto 'Super Shintosa' (Cucurbita maxima x C. moschata), an interspecific hybrid squash rootstock. The field experiment was arranged in a split-plot design with four replications. The whole plot treatments included the four combinations of PGPR (with and without) and fertilization methods (organic and conventional), while the subplot treatments included the grafted 'Tasty Bites' and the non-grafted melon plants as the control. Grafting and PGPR application did not affect marketable fruit yield per plant, whereas organic fertilization significantly reduced marketable fruit yield, primarily due to the decrease in average fruit weight. Grafting resulted in fewer marketable fruit per plant but greater average fruit weight. At the final harvest, grafted plants led to significantly higher root galling ratings and root-knot nematode population densities in the soil as compared with the non-grafted control. Interestingly, the root galling severity in grafted plants was reduced by the use of PGPR.