球孢白僵菌与哈茨木霉对玉米苗期促生抗逆的影响

Effects of Beauveria bassiana and Trichoderma harzianum on Growth Promotion and Stress Resistance of Maize Seedlings

为探明真菌内生特性对玉米苗期的促生抗逆效果,本研究以球孢白僵菌(Beauveria basssiana)和哈茨木霉(Trichoderma harzianum)为研究对象,设置4个处理,包括CK(无菌水施用土壤)、BB(球孢白僵菌孢悬液施用土壤)、TH(哈茨木霉孢悬液施用土壤)和BB+TH(球孢白僵菌与哈茨木霉孢悬液联合施用土壤),分析不同处理对玉米苗期生长指标和生理生化特性的影响。结果表明,接种后10 d,BB+TH处理玉米叶、茎中的菌定殖率显著提高,分别达到39.80%和75.60%;而根部的定殖率仅次于TH处理,达82.40%,二者差异不显著。接种后20 d,BB+TH处理茎和根中的菌定殖率最高。接种后30 d,BB+TH处理叶、茎和根中的菌定殖率均最高。接种后10、20、30 d,BB+TH处理的地上部干重、根干重和总生物量在不同采样期均最高,且均显著高于CK。BB、TH和BB+TH处理的株高、茎粗、最大叶长和叶宽、叶片SPAD值在不同采样期均高于CK,且均以BB+TH处理最高。接种后3 d和7 d,BB+TH处理的叶绿素a和叶绿素a+b含量均显著高于CK,叶绿素b和类胡萝卜素含量在接种后7 d显著高于CK。接种后3 d,各处理叶片净光合速率和气孔导度间无显著差异;接种后7 d,BB和BB+TH处理叶片净光合速率显著高于CK,BB+TH处理叶片气孔导度显著高于CK。BB+TH处理叶片过氧化氢酶(CAT)、超氧化物歧化酶(SOD)和过氧化物酶(POD)活性均显著高于CK。综上,本试验条件下球孢白僵菌和哈茨木霉均有促进玉米生长和提高抗逆性的作用,且以两种真菌联合施用效果更优。这为球孢白僵菌和哈茨木霉在农业生产实际中的联合施用提供了理论参考。

In this study,Beauveria basssiana and Trichoderma harzianum were selected as subjects to ex-plore the effects of fungal endophytic characteristics on growth promotion and stress resistance of maize at seed-ling stage.Four treatments were set as CK(soil applied with sterile water),BB(soil applied with spore sus-pension of B.bassiana),TH(soil applied with spore suspension of T.harzianum)and BB+TH(soil applied with the spore suspension of B.bassiana and T.harzianum).The effects of different treatments on the growth indexes and physiological and biochemical characteristics of maize seedlings were analyzed.The results showed that at 10 days after inoculation,the colonization rate of the fungi in leaves and stems of maize under BB+TH treatment increased significantly,reaching 39.80%and 75.60%,respectively.The colonization rate in roots under BB+TH treatment reached 82.40%,second only to TH treatment,and their difference was not signifi-cant.At 20 days after inoculation,the colonization rate of the in stems fungi and roots was the highest under BB+TH treatment.At 30 days after inoculation,the colonization rates of the fungi in leaves,stems and roots under BB+TH treatment were the highest.At 10,20 and 30 days after inoculation,the aboveground dry weight,root dry weight and total biomass under BB+TH treatment were the highest in different sampling peri-ods,and were significantly higher than those of CK.The plant height,stem diameter,maximum leaf length and width,and leaf SPAD value under BB,TH and BB+TH treatments were all higher compared to CK in dif-ferent sampling periods,and those under BB+TH treatment were the highest.At 3 and 7 days after inocula-tion,the contents of the chlorophyll a and chlorophyll a+b in BB+TH treatment were significantly higher than those in CK,and that of chlorophyll b and carotenoid were significantly higher than those in CK at 7 days after inoculation.There were no significant differences in photosynthetic rate and stomatal conductance among all treatments at 3 days after inoculation.The net photosynthetic rate of BB and BB+TH treated leaves was signifi-cantly higher than that of CK at 7 days after inoculation,and the stomatal conductance of BB+TH treated leav-es was significantly higher than that of CK.The activity of catalase(CAT),superoxide dismutase(SOD)and peroxidase(POD)in BB+TH treated leaves were significantly higher than those in CK.In conclusion,both B.bassiana and T.harzianum had the effects of promoting maize growth and improving stress tolerance under the experimental conditions,and the combined application of the two fungi was better.This study could provide theoretical references for the combined application of B.bassiana and T.harzianum in agricultural production practice.