Exocyst subunit BcSec3 regulates growth, development and pathogenicity in Botrytis cinerea

  • PDF / 8,075,109 Bytes
  • 12 Pages / 595.276 x 790.866 pts Page_size
  • 27 Downloads / 176 Views

DOWNLOAD

REPORT


Ó Indian Academy of Sciences (0123456789().,-volV) (0123456789().,-volV)

Exocyst subunit BcSec3 regulates growth, development and pathogenicity in Botrytis cinerea ZHIWEI MA1, ZHIXIONG CHEN1, WEIXIA WANG2, KUN WANG1* and TINGHENG ZHU1* 1

2

College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, Zhejiang, China

State Key Lab of Rice Biology, China National Rice Research Institute, Hangzhou, Zhejiang, China *Corresponding authors (Emails, [email protected]; [email protected]) MS received 2 May 2020; accepted 16 September 2020

Botrytis cinerea is a saprophytic plant pathogenic fungus that can infect a variety of crops and cause gray mold, which leads to huge losses worldwide. The role of exocyst in fungal pathogenicity is being revealed. In this study, homologous recombination technology was used to knock out the exocyst subunit BcSec3 of B. cinerea, and it was found that the BcSec3 subunit plays a crucial role in the growth and pathogenicity of B. cinerea. Compared with the wild-type strain B05.10, the mycelial growth ability of the BcSec3 deletion strain was reduced by up to 49.8%, the conidia production capacity of the deletion strain was severely lost, and no sclerotia was formed. The polygalacturonase, is one of plant cell wall hydrolases, whose activity in BcSec3 deletion strain was significantly reduced. In the tomato leaves infection assay in vitro, the lesion area caused by the BcSec3 deletion strain was only 20% of the wild type after 5 days of infection. Observation by light microscope showed that the morphology of BcSec3 deletion strain mycelium was significantly changed, the mycelium became thinner and deformed, and the polarity growth was not obvious. Further observation with laser confocal microscopy and transmission electron microscopy was conducted. It was found that compared with the wild type, the number of vesicles in BcSec3 deleted cells reduced and localization and distribution of vesicles changed. In mutant cell, vesicles relatively concentrated in the cytoplasm, while in wild-type cell mainly concentrated inside the cell membrane. These evidences indicate that the exocyst subunit BcSec3 plays an important role in the growth, development and pathogenicity of B. cinerea. Keywords.

Botrytis cinerea; BcSec3; growth; pathogenicity

1. Introduction Botrytis cinerea is a saprophytic phytopathogenic fungus that occurs worldwide and causes gray mold in more than 1400 host plants, including solanaceous vegetables, cucurbits, strawberries and ornamentals (Elad et al. 2016; Dean et al. 2012). B. cinerea not only affects the growth period of the plant, but also its storage (Katiyar et al. 2015). The economic losses caused by B. cinerea are huge, reaching up to 10 billion US dollars per year worldwide (Patel et al. 2015). As a typical saprophytic plant pathogenic fungus, B. cinerea uses toxic secondary metabolites as molecular weapons to induce plant cell death and feed on dead http://www.ias.ac.in/jbiosci

organisms (Antoine et al. 2019). B. cinerea is difficult to cont