玉米-茅苍术间套作系统种间根际效应增加茅苍术生产力的机理研究

There are differences between the cultivation environments and the wild natural habitats of some Traditional Chinese Medicines(TCM). and the biodiversity of the cultivation environment is reduced, resulting in problems such as high incidence of diseases and insect pests, failure of medicinal ingredients, and so on. Atractylodes lancea is a typical representative. Previous studies have shown that intercropping maize-Atractylodes lancea can improve the survival rate, yield, and sesquiterpene volatile oil content of Atractylodes lancea, but the mechanism is not clear. "rhizosphere interaction mechanism of intercropping between Chinese medicinal materials" as a study of typical scientific issues,need further study.. The field-in-place experiment and the laboratory root box test were used to study : ① The difference of root exudates, soil physicochemical factors, soil enzymes, and microorganisms between intercropping and monocropping ; ②The physiological ecology mechanisms of the inter-rhizosphere effects on the yield of Atractylodes lancea ; ③The molecular mechanisms of the inter-rhizosphere effects on the signal substances of sesquiterpene volatile oil synthesis, expression of key enzyme genes, and regulation of end product accumulation in Atractylodes lancea. An attempt was made to find the mechanism by which the rhizosphere effects of intercropping systems in the maize-Atractylosa intercropping system increased the productivity of Atractylodes lancea.. This study has practical significance for the green and efficient production of Atractylodes lancea. At the same time, it provides theoretical basis and technical decisions for the interplanting, imitation of wild cultivation, and various ecological planting patterns of partial shade and shade cultivation of Traditional Chinese Medicines.

中药材人工栽培环境与野生环境存在差异，生物多样性降低，导致出现病虫害高发、药材成分不达标等问题，茅苍术是典型代表。前期研究表明玉米-茅苍术间套作可以提高茅苍术的存活率、产量和倍半萜类挥发油含量，但其影响机理不清楚。将其作为研究“中药材间套作种间根际作用机理”科学问题的典型代表，有必要进行深入研究。. 本文通过田间原位试验和实验室根箱试验研究: ①间套作与单作根系分泌物、土壤理化因子、土壤酶和微生物的差异；②种间根际效应对茅苍术产量影响的生理生态机制；③种间根际效应对茅苍术倍半萜类挥发油生物合成过程的信号物质、关键酶基因表达、终产物积累影响的分子机制。试图找到玉米-茅苍术间套作系统种间根际效应增加茅苍术生产力的机理。. 本研究对茅苍术的绿色高效生产具有实际意义，同时为部分阴生和耐阴药用植物栽培中的间套作、仿野生栽培、各种生态种植模式提供理论依据和技术决策。

前期研究发现，苍术与玉米间作能增加苍术的存活率，促进苍术挥发油含量的积累以及产量的提高，对苍术单作和苍术-玉米间作系统进行比较，存苗率分别为50±5.1%、60±1.6%，亩产量分别为78.8±62.1和126.9±63.2kg/亩，投入产出比分别为0.88、0.38，并且苍术醇、β-桉叶醇、苍术酮、苍术素四种挥发油含量之和分别为2.12±0.22%、3.43±0.28%。另外，前期研究表明适当的遮荫（20%-25%的遮荫度）和红蓝光9：1亦可促进苍术倍半萜类挥发油的积累。因此，苍术-玉米间作是通过哪种途径提高苍术生产力的机理值得我们深入探索。本试验设置苍术单作、苍术-玉米间作无障碍、间作隔塑料膜以及间作隔尼龙膜田间试验，进一步探索苍术-玉米间作根际效应提高苍术生产力的机理。通过测定苍术生物量、化学成分、土壤理化因子、根系分泌物和根际微生物等，初步探索出苍术玉米间作根际效应的途径。与苍术单作相比，间作中玉米根系总是趋向苍术根系生长，并在苍术根系中发现大量种间对话介质（总共1000多种，初步鉴定出18种差异化合物，其中黄酮类9种，酯类、有机酸类各2种，萜类、苯乙醇苷类、甾体、酚类、酮类各1种）。并且，苍术的根际环境会被玉米酸化（隔塑料膜苍术根际pH值4.65±0.08a，玉米间套作苍术根际pH值4.4±0.07b），这提高了苍术根际微生物的多样性，并促进苍术根际酸性微生物和根际促生菌的富集。后期回施验证试验表明，筛选到种间对话介质中的三种黄酮类根系分泌物对苍术挥发油有显著提高作用。总之，玉米能通过根系分泌物改善苍术根际土壤微生态环境，使苍术根际富集大量根际促生菌，从而促进苍术的生长和挥发油含量的积累。苍术-玉米间套作能够借助生物多样性的健康环境，提高药材品质，增加经济效益，生态、社会效益高度统一，可以为“天地人药合一”的中药生态种植提供典型范例。