Abstract:To reveal the effects of shoot pinching on the growth, sucrose and starch metabolism in ‘Kyoho’ grape (Vitis vinifera×V. labrusca) and its mechanism, the phenotype of leaves and stems, accumulation characteristics of soluble solids, sucrose and starch in fruits, and expression of genes related to sucrose and starch metabolism were studied by different ways of shoot pinching. The results showed that shoot pinching inhibited leaf growth and stem enlargement of ‘Kyoho’, but promoted the rapid growth of inflorescence in early stage, and increasing fruit weight, ear weight, plant yield and soluble solid content. The contents of sucrose in leaves, sucrose and starch in stems increased in late stage under 2-leaf pinching, and the expression of SPS, NI and CWI in sucrose metabolism enhanced, while that of AMY in starch metabolism inhibited. Therefore, it was suggested that 2-leaf pinching could regulate the expression of SPS, NI, CWI and AMY genes, and promoted sucrose synthesis and starch accumulation, laying a nutritional foundation for fruit ripening, germination and flowering.
