Zinc and Boron on growth of grapes cv. Muscat

摘要

Micronutrient deficiency has become a serious problem in many parts of India and it is one of the major factors limiting the growth of grapes in Tamil Nadu. Grapes contribute fifty per cent of the total production of fruits in the world. In Tamil Nadu it is grown in an area of 2475 ha, with an annual production of 47420 tonnes. The climatic conditions are favourable in parts of Tamil Nadu and so that five crops are taken in two years by staggered pruning techniques. As the cultivation of grapes isfast expanding it is being taken up on a wide range of soils and agroclimatic situations, especially in Madurai, Theni, Dindigul, Dharmapurl and Coimbatore districts of Tamil Nadu state. Muscat is the most ideal cultivar in TamilNadu. Many workers have reported positive effects of Zn and B on growth and quality of grapes. Application of Zn and B increased the growth (Volschenk et al. 1999 and Mahorker and Patil, 1987) in Thomson seedless. Information regarding the effect of Zn and B nutrition on growthof grape is lacking under local conditions for Muscat. Hence the present study was undertaken at TamilNadu Agricultural University, Coimbatore, to study the effect of Zn and B nutrition on the growth of grapes and to suggest a suitable method for Zn andB application. The present study was undertaken at a farmer's field at Mathampatti during the year 1999-2000 on fully grown six-year-old Muscat grape vines. The sandy loam soil contained pH 8.1, organic carbon 0.52 percent, DTPA Zn 1.05 ppm and hotwatersoluble B 0.23 ppm. The experiment was laid out in a randomized block design having 12 treatments each replicated three times. ZnSO_4 at two levels (10g and 20g vine~(-1)), borax at two levels (4g and 8g vine~(-1)) and combination of these two nutrientswere applied in soil after pruning. Foliar application of ZnSO_4 0.5 percent, borax 0.2 percent and combination of these nutrients done at vegetative (20 days after pruning) and full bloom stages and they considered as separate treatments. The doses weresupplemented with recommended doses of NPK 250,160 and 600g vine~(-1) respectively. Growth observations were recorded in three stages,30, 60 and 90 days after pruning. Shoot length, number of intenodes and number of leaves shoot~(-1) were recorded. Forthat five shoots in each treatment were selected at random and the measurements on shoot length were recorded during 30, 60 and 90 days after pruning and expressed in centimeters.