Abstract:

The experiments were continuously conducted under protected condition in 2009 and 2010, in order to elucidate the effects of different compound fertilizing levels on fruit quality, leaf petiole nutrient absorption, and leaf net photosynthetic rate of ‘Jumeigui’ grape at the stage of fruit cell rapid elongation. NPK compound fertilizer of six levels was top-dressed to ‘Jumeigui’ grape trees. The related characteristics of fruit quality, nitrogen (N), phosphate (P), and potassium (K) content of leaf petiole, leaf net photosynthetic rate (Pn), were investigated and compared. The results showed that, when the fertilizer level exceeded 300 kg/hm2, there were no significant differences of average berry weight, total soluble solid content (TSS), titrate-acid (TA), and fruit firmness among the treatments. The leaf petiole N, P, K had not changed significantly among different fertilizing level. Moreover, although fertilizing increased the leaf Pn compared to the control, it was not significantly affected by different fertilizing levels. Therefore, integrating these results, we concluded that, under the protected condition of ‘Jumeigui’ grape, the feasible fertilizing amount may be about 300 kg/hm2.