Primary Study On Papaya Greenhouse Cultivation In Hangzhou

Papaya or pawpaw (Carica papaya L.) is a perennial woody plant species and is a tropical or subtropical evergreen plant. Papaya is an excellent fruit due to its high nutritional value. It contains large quantities of vitamins, papaya alkali, papaya alcohol, diverse amino acids and papain, therefore, it was called 'king of fruits'.Papaya was originated in south America and was transferred to China in the 17^th century. It has a long history of cultivation for more than 300 years and now is a common fruit in south China. Traditionally, papaya was scarcely cultivated. However, since 1990's the large scale production of papaya has come into being and major production districts are Taiwan, Hainan, Guangdong, Guangxi, Yunnan and Fujian.The successful cultivation of papaya is readily to achieve in areas south to Fujian. The plants could survive in the north areas, however, the fruits could not become fully ripen due to inadequate temperature accumulation. After comparison of the cultivation modes in different areas and taking account of the climate characteristics of Hangzhou, we adopted the annual cultivation model. Sowing and nursing in autumn, keeping a constant temperature of nursery bed in winter and transferring the seedlings to protected field in spring of next year, the(?) measures would accelerate flowing of papaya and ripping of the fruits and the plants complete the full life cycle. In addition, the regulation of vegetative and reproductive growth by reducing the number of flower and fruits contribute to the final fruits production. And in the later phase of development cutting the tip of plant is not influence on fruits production. The comparison experiment was carried out between four cultivars, Tainong #2, Hawaii, Sunrising and Suizhonghong. The results demonstrated that Tainong #2 could acclimate to the low temperature especially in the later phase of development and has remarkable advantages such as high production and quality. This is a variety worth promotion in Hangzhou market by virtue of the traits mentioned above.