Adaptability And Demonstration Evaluation Of Citrus Superior Varieties In Southern Guizhou

The researches is this which supported by "Tenth five years" key technologies R & D programme: Industrialization development of high quality citrus in Karst and valley areas in Guizhou, mainly had investigated natural conditions (including topographic features, climatic conditions, soil situations and so on) of most citrus producing county, production status, adaptability of part improved varieties (phonophase, growth increment of tree body, growth dynamics of fruits, analysis of fruit quality and yield ) and production demonstration evaluation of superior citrus in the south of Guizhou. The result shows: south of Guizhou, where the mean annual temperature is between 18°C and 21°C, the mean annual effective accumulated temperature(≥10℃) is between 6000℃and 7000℃, the mean annual frost-free periods are between 320 and 365 days, the mean annual sunshine times are between 1350 hours and 1520 hours, the mean annual precipitation is between 1,200mm and 1,400mm, was the optimum area for Citrus planting. In the suitable regions, where high-quality and fresh fruits of citrus could be produced, was around 920 thousand mu. Navel oranges, such as Bonaza, Newhall and Harvest, could be the major varieties in Guizhou because of theirs high yield, high-quality and vigorous. In this area, fruit trees had the characteristics of early ripening by the special nature condition, so it provided board prospects for the construction of production base of fresh fruits. At the same time, The researches evaluated scientifically on the production and demonstration of citrus according to investigation of the favorable factors and unfavorable factors in the south of Guizhou. It thought that large-scale development of citrus must implement the brand strategy, devote great efforts to adjusting products structure and give priority to fresh fruits such as navel orange of high quality, Ponkan and Mandarin of premature. Because of superior in climate condition (warm winter and early spring etc.) in north-south of Panjiang, the Hongshui river valley zones with lower altitudes and tropical climate such as Luodian, Ceheng, Wangmo, Zhengfeng, Xingyi, which are favorable for flower bud differentiation and flowering and fruit bearing, orange grew quickly and fruit early. Production base for orange especially for navel orange should be established to form a local characteristic fruit industrial belt. What's more, traditional cultivation and management should be changed with development of science and technology, sod culture and dry weeds cover around tree bases should be carried out and non-polluted citrus production technology should be extended. By means of comprehensive controlling of diseases and pests and eco-agricultural model of pig-biogas-fruit, applying physical pest-killing technique, bio-control and bio-organic manure to reduce the cost of production and improve benefit of economy. Meanwhile, standardization production must be carried out to reflect the inherent properties and no pollution production of fruits.