Effects of Colored Shade Nets on Grapes and Leaves of Shine Muscat Grown under Greenhouse Conditions

Greenhouse grapes are often ripened at very high temperatures in the south of China, however, high temperatures are detrimental to their ripening. To moderate the strong light and high temperature conditions of the growing environment, different colored shade nets (green, blue, and black) were used to cover Shine Muscat (Vitis labruscana L.H. Bailey × Vitis vinifera L.) grapes during the ripening period. Differences in the cooling effect, fruit appearance and taste, and leaf photosynthetic performance were analyzed. It was found that the shading treatment exerted a significant cooling effect, and the light transmittance of blue and green shade nets was significantly higher than that of the black shade net. Shine Muscat grapes grown under shading treatment conditions were found to have more consistent total soluble solids content and coloring. Shading was found to affect the aroma of grapes, but the effect of the green shade net treatment was lower. The shading treatments slightly alleviated the senescence of old leaves. The shading treatments were found to improve the consistency of Shine Muscat grape berries. Of the shading treatments, the green and blue shade nets were found to be most effective and can be used to cultivate high quality grapes.