长期连作对大豆根际真菌主要类群的影响

Effect of Soybean Long Term Continual Cropping on Main Groups of Rhizosphere Fungi

在大豆长期定位试验区,取生育期内大豆连作16a、轮作、米豆迎茬和大豆连作1a根际土壤,调查真菌总数及其主要类群数量,探讨长期连作对大豆根际真菌主要类群的影响。试验结果表明,不同轮作系统大豆根际真菌总数从高到低依次为大豆连作1a>米豆迎茬>轮作>大豆连作16a;青霉数量从高到低依次为大豆连作1a>轮作>米豆迎茬>大豆连作16a;木霉数量在整个生育期内变化规律相差较大,木霉数量由高到低依次为米豆迎茬>连作16a>连作1a>轮作;连作16a在苗期(V3)时镰孢菌数量最高,以后均低于轮作处理,鼓粒期(R5)和成熟期(R8)轮作镰孢菌数量最高。

On the long- term experiment in situ, soybean rhizosphere soils in different growth stages of soybean continual cropping for 16 years （S - S... S）, wheat - corn - soybean （W - C - S... W - C - S）, corn - soybean （ C - S... C - S） and corn - soybean - soybean （ C - S - S... C - S - S） were sampled for the investigation of soil fungi and the main groups, to study the effect of soybean long term continual cropping on the fungi main groups change of soybean rhizosphere. The results show that： the total CFU/g dry soil of fungi descending order in different soybean rotation systems was C - S - S... C - S - S 〉 C - S... C - S 〉 W - C - S... W - C - S 〉 S - S... S; the quantity of Penicillium spp. in different soybean rotations from high to low was C - S - S... C - S - S 〉 W - C - S... W - C - S 〉 C - S... C - S 〉 S - S... S; in all the soybean ~rowth stages, the quantity dynamic of Trichoderma spp. in different soybean rotation systems varied, and the descending order of Trichoderma spp. quantity was C - S... C - S 〉 S - S... S 〉 C - S - S... C - S - S 〉 W - C - S... W - C - S; the quantity of Fusarium spp. was highest in S - S... S, and all lower than W - C - S... W - C - S after V5, the quantity of Fusarium spp. was higher at R5 and R8 in W- C - S... W- C - S than others.