Influence of Mineral Nutrients on Growth, Yield, Berry Quality, and Petiole Mineral Nutrient Concentrations of Table Grape

ABSTRACT

The effect of various combination of macro (N, Mg, and K) and micronutrients (Fe and Zn) on yield, fruit quality, and tissue mineral concentrations of an important commercial table grape cultivar (Vitis vinifera cv. Bidaneh Qermez) was studied over three growing seasons of 1999–2001. Yield, fruit set, cluster weight, cluster number, berry size and quality attributes (soluble solid concentrations, pH, K-skin) were influenced by N, K, Mg, Fe, and Zn applications. Potassium application increased cluster number and weight, which resulted in a significant increase in the yield. Potassium influenced berry quality attributes more than other applied mineral elements. Yield was positively correlated to the soil total N at 30–60 cm depth. Nitrogen application increased growth of the main and lateral canes. Soil N did not correlate strongly with tissue N status.

Keywords:

• Cluster weight
• juice pH
• reproductive growth
• vegetative growth

ACKNOWLEDGMENT

This research project has been supported by grant number NRCI 5383 of National Research Project and with the support of National Research Council of I. R. of Iran. Special thanks to the University of Zanjan and the Agricultural and Industrial Co. of Khoramdareh, Iran, for their support in various parts of this project. Also, cooperation of the University of Idaho Pomology Program, USA in this project is greatly appreciated.

Notes

∗Each value is average over three years (1999–2001). Mean separation within columns by Duncan's multiple range test at P = 0.05.

∗∗Crop load efficiency is yield per vine/vine pruning weight.