青岛莱西地区草莓根腐病菌鉴定及其拮抗木霉的筛选

Identification of Pathogens Causing Root Rot on Strawberry in Qingdao Laixi and Screening of Their Antibiotic Trichoderma spp.

于2018—2019年从青岛莱西地区10个草莓种植基地的30个采样点共采集90份草莓根腐病病样,利用组织分离法对病原菌进行了分离,结合形态学和分子生物学鉴定以及致病性测定,以确定引起该地区草莓根腐病的病原菌种类,同时初步测试了4株木霉对病原菌的抑菌效果及抑菌机理。结果表明,共分离到6种真菌,分别为胶孢炭疽菌(Colletotrichum gloeosporioides)、尖孢镰刀菌(Fusarium oxysporum)、新棒状拟盘多毛孢(Neopestalotiopsis clavispora)、枝状枝孢(Cladosporium cladosporioides)、菌核生枝顶孢(Acremonium sclerotigenum)和土曲霉(Aspergillus terreus)。前三者为草莓根腐病菌,胶孢炭疽菌和尖孢镰刀菌的分离频度分别为45.8%和32.1%,是优势病原菌,新棒状拟盘多毛孢分离频度为8.4%。4株木霉通过竞争作用、产生非挥发性菌代谢产物抑制3种病原菌生长。培养3 d时,4株木霉代谢产物对3种病原菌的抑菌率为100%;培养7 d时下降,其中Ta1和Th2抑菌效果最好,前者对胶孢炭疽菌、尖孢镰刀菌和新棒状拟盘多毛孢的抑菌率分别为74.1%、62.5%和75.0%,后者分别为74.1%、73.8%和75.9%。二者对草莓根腐病具有一定生防潜力。

Ninety samples were collected from 30 plots in 10 strawberry planting bases in Qingdao Laixi from 2018 to 2019,and isolated by tissue isolating method, combined with morphology, molecular biological technology and pathogenic test, the species causing root rot of strawberries were identified, meanwhile, antibiotic effects and mechanisms of 4 Trichoderma spp. to the pathogens were studied. The results indicated that 6 fungal species were isolated from rotten tissues of strawberries, including Colletotrichum gloeosporioides, Fusarium oxysporum, Neopestalotiopsis clavispora, Cladosporium cladosporioides, Acremonium sclerotigenum and Aspergillus terreus. Among them, the first three was the pathogens causing root rot of strawberries, the document frequency(DF) of C. gloeosporioides and F. oxysporum was 45.8% and 32.1%, respectively, while that of N. clavispora was 8.4%. Four Trichoderma spp. inhibited the above pathogens by competition and production of non-volatile compounds. After three days of inoculation, the inhibition percentage of the 4 Trichoderma spp. to the three pathogens were 100%, however, seven days after inoculation, the inhibition percentage decreased, the inhibition percentage of trichoderma Ta1 and Th2 were the highest, those of Ta1 to C. gloeosporioides, F. oxysporum and N. clavispora were 74.1%, 62.5% and 75.0%, respectively;those of Th1 were 74.1%, 73.8% and 75.9%, respectively. Therefore, Ta1 and Th2 had the best antibiotic effects and biocontrol potentials against root rot of strawberries.