| Since the pollution became an increasingly serious problem in our planet, green and pollution-free technologies are imperious demands with the development of modern agriculture. Microbial Pesticides, as a main force, is becoming more and more important in the area of biological pest control. In this area, plant endophytic fungi provide a novel mind and enlarge this field with its special habitat and ecology which contained many potential microbial resources. In this study, one strain expressing agglutinin were constructed by gene engineering and made it to have a high resistance to pest. And the results are shown as follows:1. Nine strains of endophytic fungi were isolated from rape. Then through morphological observation of spores and sequence analysis of 18SrRNA gene, six of them were identified as species of Alternaria alternate; one of them were identified as species of Chaetomium globosum; and two left strains were species of Fusarium and Xylariales respectively.2. From these nine strains, one strain of C. globosum (YY-11) was selected as it has strong antifungal bioactivity. The results of plate confronting test showed that this endophytic fungi strain had different inhibiting effects to Rhizoctonia solani, Botiytis cinerea, Sclerotinia sclerotiorum and Fusarium graminearum etc. The mechanism of antagonism between C.globosum (YY-11) and R.solani was studied in the way of confrontation on slide. It is found that C.globosum has apparent process of mycoparasitism which including the ways of intruding, winding around and attaching to inhibit the growth of such pathogenic fungi.3. The result of re-inoculation test showed that this strain has a wide range of host-plants. YY-11 could infect and colonize in many important crops such as rape, wheat, rice, cotton, radish and maize. The colonizing time is long as it could be isolated from host seedling after three months. The result of observation to the process of infect and colonize showed that the mycelium of YY-11 can intrude and habitat in the intercellular space of the rape root. 4. The two expression vectors which containing Arisaema heterophyllum agglutinin (AHA) or Pinellia ternata agglutinin (PTA) gene was constructed and transformed respec-tively into the ascospores of YY-11 mediated by Agrobacterium tumefaciens, and the pos-itive transformant (T2, Te and P6) was selected and verified by Hygromycin resistance, PCR, SDS-PAGE and western blot assay.5. The result of anti-aphid activity of recombinant C. globosum (YY-11) in rape seedlings showed that these seedlings inoculated with recombinant YY-11 could significantly inhibit the growth and reproduction of aphid. The aphid number in these groups were significantly lower P<0.01 than that in control group from day 5, which condition could maintained stably for a long time only have some slightly fluctuations. Moreover, seedlings inoculated with recombinant C. globosum could also effectively resist S. sclerotiorum.The strain of endophytic C. globosum could colonize stably in many plants and have strong anti-septic activity; while the recombinant strain could have effective aphid resistance. Our results indicated that endophytic fungi could be used as a living vector for expressing anti-pest toxic proteins to develop biological control agents with double effects for controlling both plant diseases and pests.
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