Transformation of the endophytic fungus Acremonium implicatum with GFP and evaluation of its biocontrol effect against Meloidogyne incognita.
Acremonium implicatum is an endophytic fungus with biocontrol potential against Meloidogyne incognita based on its opportunistic egg-parasitic, hatching inhibition, and toxic properties. To understand its mode of plant endophytism and opportunistic egg parasitism, GFP-tagged A. implicatum was constructed by PEG-mediated protoplast transformation. By laser scanning confocal microscopy (LSCM), we evaluated the endophytism and opportunistic egg parasitism of a stable gfp transformant (Acr-1). Acr-1 could colonize epidermal tissue, cortical tissue, and xylem of roots and form a mutualistic symbiosis with tomato host plants. LSCM of Acr-1 infecting M. incognita eggs revealed that hyphae penetrated the shell and grew inside eggs to form trophic hyphae. A large number of hyphae enveloped parasitized eggs. In addition, the egg shell integrity was destroyed by fungal penetration. The percentage of egg parasitism was 33.8 %. There were no marked differences between the wild type and mutant in nematode second-stage juvenile mortality and egg hatching and in fungal control efficiency in a pot experiment. In conclusion, gfp-transformation did not change the nematicidal activity of A. implicatum and is a tool to examine the mode of plant endophytism and opportunistic egg parasitism of A. implicatum.
Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, South Street No. 12, Zhongguancun, Haidian, Beijing, 100081, People's Republic of China.
Yu-Rong
YR
Yao
Xue-Liang
XL
Tian
Bao-Ming
BM
Shen
Zhen-Chuan
ZC
Mao
Guo-Hua
GH
Chen
Bing-Yan
BY
Xie
D000164:Acremonium / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D000818:Animals; D000898:Antibiosis; D060026:Endophytes / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D025301:Hyphae / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D018551:Solanum lycopersicum / Q000469:parasitology*; D010572:Pest Control, Biological / Q000379:methods*; D010935:Plant Diseases / Q000469:parasitology*; D013559:Symbiosis; D014170:Transformation, Genetic; D014431:Tylenchoidea / Q000382:microbiology / Q000502:physiology*
D049452:Green Fluorescent Proteins