The Effect of Different Covering Times With Plastic on Yield and Quality of Some Table Grape Cultivars

摘要

Table grapes are usually grown under plastic cover or sheets for early production. In this work, effectiveness of plastic sheet covered at two different times on the earliness and quality characteristics of some table grape cultivars were searched. Grapevines trained on a bilateral cordon trellis were grown under 2.5 m height and 3.0 m wide tunnel covered with UV+IR (Ultra violet+Infra red) type of polyethylene (PE). In result, average cluster, berry weight and their size were decreased under PE. However, uniformity in berry size and color and total shoot length and growth did not differ among applications. PE was found efficient to enhance the maturation of berries about 17 and 14 days when the tunnel covered at 16th of February and 9th of March respectively. In addition to these, it was found that the protected cultivation was more economic than open field growing.