基于平衡施肥的水肥耦合对油茶果实产量及品质的作用机理

Camellia oleifera Abel is a unique edible oil woody plant in the southern of China, and the management of irrigation and fertilization is very important to its high yield, however the research of international relation between the water and fertilization management and productivity is not enough. Take the water regime of the forest land based on the soil testing and formulated fertilization into consideration, to research the water and fertilizer coupling effect to the Camellia oleifera Abel's yield and quality, and study the mechanism of action based on its morphology and physiology, in this thesis. Study the rhizosphere soil nutrient dynamics, efficiency of soil water and nutrient usage, photosynthetic physiology, biomass accumulation dynamic in the flower and fruit, fruit growth and oil transformation process, under the condition of water and fertilizer coupling, according different fertilizing amount and water amount, and analyzing the water and fertilizer coupling effect to its yield and quality's mechanism of action. The research result provides scientific evidence for the nutrient intensive management, and promotes production growth, and is very important to promote the development of the Camellia oleifera Abel industry.

油茶是我国南方重点发展的木本食用油料树种，实现油茶高产必须进行集约高效的水肥管理，而水肥与油茶生产力之间的内在关系缺乏系统研究。本项目在测土配方施肥的基础上综合考虑油茶林地水分状况，研究水肥耦合对油茶果实产量和品质的影响，并从形态和生理上探讨其作用机理。项目通过设置不同施肥量和灌水量，深入研究水肥耦合条件下，油茶根际土壤养分动态，油茶林地水分和养分利用效率、油茶叶片光合生理、叶和果干物质积累动态、花和果数量动态、果实生长及油脂转化进程；并结合油茶产量和品质特征，探求水肥耦合对油茶果实产量和品质的作用机理。研究结果可为油茶林地依据土壤水分状况进行集约养分管理提供科学依据，对促进我国油茶增产增效，推动油茶产业发展具有十分重要的意义。

项目以高产无性系油茶为试验对象，在测定试验样地土壤的养分和调查样地油茶生长情况的基础上，采用二次通用旋转组合设计，针对氮肥（N）、磷肥（P2O5）、钾肥（K2O）和灌水（H2O）四个影响油茶生长发育的主要影响因子，设置了水肥组合试验。通过定期测定油茶林地土壤和树体中的养分含量、叶片光合效率等指标，调查油茶树体的水分动态及油茶果实生长、油脂转化进程，并根据调查测定结果分析了油茶产量、品质与诸多形态、生理因子之间的关系，探讨了水肥耦合对油茶果实产量和品质的作用机理。通过研究确定了获得最高油茶产量的水肥组合：全年每株油茶施有效养分即全年每株油茶增施有效养分N 181.8 g、P2O5 87.3 g、K2O 275.4 g，灌水29.5 kg，采用该方案，油茶鲜果产量可达3167 g/株，种仁含油率可达到54.45%，单株可产油388 g。探明了水肥耦合促进油茶果实生长和油脂转化的机理：水肥耦合条件下，油茶果实含油率、产量与叶片和果实的养分含量、叶片的光合生理指标、春梢的生长情况密切相关，水肥的合理施用促进了油茶春梢生长和其上叶片、果实对养分的积累，增强了叶片了光合效能，从而提高了油茶果实产量和含油量。研究结果为油茶林精准水肥管理提供了科学依据，对促进油茶高产，推动油茶产业发展具有重要的意义。