地下穴贮滴灌对干旱区葡萄根系形态发育及光合同化物积累分配的影响

Currently, drip irrigation technology has been widely applied to forest and fruit production in the arid regions in Xinjiang, but as is discovered in production, since surface drip irrigation shallows fruit tree roots and aggravates secondary salinization, the sustainable development of forestry and fruit farming in Xinjiang has been impacted. This study will take self-designed “water-fertilizer-air” integration technology based on subsurface drip irrigation with tank as the research characteristics and proceed along a route from different irrigation quantity and aerated irrigation periods based on subsurface dip irrigation with tank to the temporal and spatial variation of root-zone soil moisture, the distribution and physiological functions of grape roots, and the difference of photoassimilates in accumulation and distribution. Then, we will investigate the influence of different irrigation quantity and aerated irrigation periods based on subsurface dip irrigation with tank on water movement in grape roots, root morphology, microstructure, physiological function, as well as the accumulation and distribution of photoassimilates by in-situ root monitoring, hydrogen and oxygen isotope labeling, carbon tracer labeling, and conventional physiological and biochemical technologies. Our study aims to explore how to optimize structure and physiological function of root by controlling supply of water and air in grape root zone to adjust aerial part growth. Also, an optimal irrigation quantity and aerated irrigation periods proper for grape growth and development in arid regions will be determined for subsurface dip irrigation with tank, providing a theoretical basis for the popularization and application of advanced water saving technologies.

目前滴灌技术已在新疆干旱区林果生产上进行了较大规模推广应用，但生产中发现地表滴灌导致果树根系上浮、次生盐渍化加剧，影响新疆林果产业的可持续发展。本研究以自主设计的地下穴贮滴灌“水肥气”一体化技术为切入点，以“地下穴贮滴灌不同灌水量及加气灌溉—根区土壤水分时空变化—葡萄根系分布及生理功能—光合同化物积累分配差异”为研究路线。通过根系原位监测、氢氧同位素、碳示踪标记及常规生理生化技术相结合的方法，探讨地下穴贮滴灌不同灌水量、加气灌溉时期对葡萄根区水分运移、根系形态、微观结构、生理功能及光合同化物积累分配的影响，探索出通过调控葡萄根区水、气供应状况实现局部根系结构及生理功能优化进而调节地上部生长，明确基于地下穴贮滴灌适宜干旱区葡萄生长发育的较佳灌水量及加气灌溉时期，为先进节水技术的推广和应用提供一定理论依据。

本项目针对在新疆干旱区林果生产上进行了较大规模推广应用的地表滴灌导致果树根系上浮、次生盐渍化加剧的问题。利用根系原位监测、扫描电镜、碳氮同位素示踪标记和理生化技术相结合的方法重点开展了（1）加气灌溉对葡萄生长和不同形态氮素的吸收利用、根际土壤化学特性及细菌群落结构的影响（2）根际加气对 葡萄幼苗生长及其对15N的吸收、分布和利用影响（3）果树穴贮滴灌增施有机肥和减施化肥对葡萄生长、品质、养分、葡萄微生物群落和果实品质的影响（4）果树穴贮砖的制作与优化，探讨不同滴灌方式对葡萄生长发育、根系形态及氮素吸收的影响。通过项目的实施，研制出地下穴贮滴灌“水肥气”一体化设备，通过碳同位素示踪标记技术研究了加气灌溉对葡萄光合同化物分配、根际二氧化碳呼吸及土壤关键酶活性的影响。结果表明细根、新枝、粗根注气处理分别比未注气处理高118.04%、163.38%、54.23%，表明加气灌溉促进光合碳同化产物向细根、新枝、粗根的分配，暗示通过注气可以促进光合产物向根系积累；通过氮同位素示踪标记表明，地下穴贮滴灌条件下无论是否注气，葡萄新生部位对硝态氮的征调能力、吸收利用效率均显著高于铵态氮，表明注气或不注气条件下葡萄根系均对硝态氮具有偏好性，当尿素作为氮素使用时，不适合进行加气灌溉；基于旱区果园葡萄品质主要受PH、电导率、有机质及微生物多样性的影响较强结论，开展了果树穴贮砖的制作及验证试验，明确了果树穴贮滴灌条件下果树穴贮砖材料的适宜配方和相关机理。本项目通过室内内在机理、田间试验验证研究探索出了通过优化滴灌方式、加气灌溉时期使光合同化物向生殖器官分配的有效途径和量化指标，可为先进节水技术在干旱区的推广和应用提供一定理论支持。本研究发表SCI/EI刊物8篇，授权实用新型专利4项，申请发明专利2项，培养博士研究生1名，硕士研究生3名。