Development of Pathogenicity and AFLP to Characterize Fusarium oxysporum f.sp. momordicae Isolates from Bitter Gourd in China

Abstract

Bitter gourd (Momordica charantia L.) cultivated in China is regarded as an important vegetable crop and is of considerable economic importance. However, it is susceptible to fusarium wilt, which causes heavy economic losses. Forty‐eight isolates were isolated from diseased bitter gourd plants that displayed typical fusarium wilt symptoms. Based on the morphological features, the rDNA internal transcribed space (ITS) sequences, pathogenicity and host biotypes, all of the isolates tested were pathogenic to the susceptible bitter gourd plants species (cv. ‘Guinongke No. 2’) and were identified as Fusarium oxysporum f. sp. momordicae (FOM). Our results classified different isolates as slightly, moderately or highly virulent. Among the isolates tested, 43 isolates slightly infected bottle gourd (Lagenaria siceraria var. clavata), whereas they did not infect other species from the family Cucurbitaceae. Genetic diversity among 48 isolates was characterized using amplified fragment length polymorphism (AFLP) analysis. The number of bands amplified by each primer pairs ranged from 41 to 66, with sizes ranging from 200 to 500 bp. A total of 366 bands were observed, out of which 363 were polymorphic (99.14%). The Nei's genetic identity of the six geographical populations varied from 0.7362 to 0.9707. The mean Nei's gene diversity index (H = 0.2644) and the mean Shannon's information index (I = 0.4071) at species level were higher than ones at populations level, indicated that the variation within populations was greater than that among populations. The Nei's GST (0.5103) and gene flow (Nm = 0.4923) revealed that genetic differentiation was mainly among populations and few gene exchanges. The dendrogram obtained from AFLP marker showed that there was a good correlation between isolates from different geographical locations and their pathogenicity. The AFLP marker effectively distinguished the high virulent isolates from the less virulent isolates. The highly virulent isolates were distinctly separated in different clusters, which indicated a significantly high correlation with the geographical origin in the AFLP dendrogram. The pathogenicity and molecular marker analysis confirmed the presence of variation in virulence as well as genetic diversity among the FOM isolates studied.

Pathogenicity and Genetic Diversity of Fusarium oxysporum Causing Soybean Root Rot in Northeast China

“…In studies on F. oxysporum from other crops analyzed by AFLP, genetic groups were found to be associated with aggressiveness of F. oxysporum f. sp. momordicae isolates (Chen et al, 2014) or vegetative compatibility group of F. oxysporum f. sp. radicis-cucumerinum isolates (Tok & Kurt, 2010).…”

“…In a study on Fusarium wilt of bitter gourd caused by F. oxysporum f. sp. momordicae, AFLP analysis differentiated isolates with high virulence from those with low virulence, and pathogenicity of the 48 pathogen isolates was correlated with geographical locations of isolation of the isolates (Chen et al, 2014). In another study on F. oxysporum f. sp.…”

“…Genomic fingerprinting techniques have been widely used to study genetic variability, population structure, and species phylogeny of F. oxysporum (Silva et al, 2013;Chen et al, 2014;Zimmermann et al, 2015). Among the techniques, amplified fragment length polymorphism (AFLP) is well recognized which has great discriminatory power (Vos et al, 1995;Mueller & Wolfenbarger, 1999;Silva et al, 2013).…”

Determination of metrafenone in bitter gourd and soil by GC with ECD

“…Bitter gourd (Momordica charantia L.) belongs to the family Cucurbitaceae, is an important vegetable crop in tropical countries, including China, Taiwan and India (Chen, Huang, Li, Wen, & Yuan, 2014;Misal, Nizakat, Amal, & Muhammad, 2005;Tusar, Ambika, Anand, & Jack, 2008;Wu, Hu, Ge, Zhao, & Wang, 2010). It contains substances with antidiabetic properties such as charantin, vicine, polypeptide-pand other unspecific bioactive components such as antioxidants (Michael & Gudrun, 2006).…”

Genetic diversity analyses ofLasiodiplodia theobromaeonMorus albaandAgave sisalanabased on RAPD and ISSR molecular markers

“…The molecular markers such as random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) have been extensively used to investigate the genetic diversity of plant pathogens at strain and population level (Wu et al 2000; Liu et al 2014; Chen et al 2015). Genetic cluster dendrogram based on the results of molecular markers often keeps a relationship with the geographical region, host, pathogenicity, vegetative compatibility group and other aspects of the tested isolates, and the genetic diversity and difference of intra- and inter-species from different sources could be understood by analysing the dendrogram (Shafagh et al 2008; Baysal et al 2010).…”