Grape response to different soil moisture regimes

Proper irrigation management, that is, optimizing the time of application and the quantity of water required by plants, plays an important role in fruit yield and quality. The present study was conducted to find out the best scheduling irrigation for peykani grape (Vitis vinifera). The prime objectives were to improve yield and quality of this crop. A field experiment was carried out using six irrigation treatments based on different phenological stages of grape and soil moisture contents, with 4 replications. This experiment was conducted using Randomized Complete Block Design in Kashmar region during 1997-2000. Grapes were harvested when the amount of soluble solids reached the value of 20-21%. Then, physical features were examined including: yield, length, and weight of grape. Chemical tests were conducted to measure the soluble solids, titrable acid, percent of moisture and pH. The results showed that different irrigation schedules had a significant effect on fruit yield and quality. Maximum yield recorded (30.1 ton/ha) was obtained with the following treatment: one irrigation at winter followed by another one before blooming; the next irrigation was on 23(rd) of may after flowering followed by 20 day intervals irrigation periods applied until harvesting time. The irrigation treatments had a significant effect on physical and chemical tests at alpha=5% and maximum values of berry length, weight and soluble solids were obtained with the treatment mentioned above.