Female fertility and mating type distribution in a Philippine population ofFusarium verticillioides

Abstract

Fusarium verticillioides is a common causal agent of maize ear rot in the Philippines. Eighty isolates were collected from healthy and infected maize cobs from Laguna province. Fifty isolates crossed with one of the mating type A testers. The ratio of MATA-1:MATA-2 is 27:23, which follows a Mendelian ratio of 1:1. The effective population number, Ne, was determined by mating type and male/hermaphrodite polymorphisms. The effective population number for mating type, Ne mt, is 81% of the count (total population), and that for male/hermaphrodite status, Ne f, is 36-42% of the count (total population). Sexual reproduction in Philippine isolates of F. verticillioides does not occur frequently, compared to F. verticillioides in other regions of the world.

Mating behavior of a Northern Italian population of Fusarium verticillioides associated with maize

“…The F. verticillioides population associated with maize grown in Northern Italy therefore seemed to be characterized by a high tolerance to female sterility mutations, during asexual reproduction, at which female fertility was lost. The comparison between the N e(f) values obtained in the present study with those calculated by other Authors pointed out that the structure of the examined Italian population more closely resembles the relatively infertile Argentinean (Chulze et al 2000) and Philippine populations (Cumagun 2007). Agricultural practices, such as tillage, under which maize was grown in the examined fields, were not likely to provide opportunity for sexual recombination, as already pointed out by Reynoso et al (2006).…”

“…Moreover, N e is usually used to evaluate populations when mating is not randomly distributed and when individual members of the population do not contribute equally to the gene pool of the progeny (Caballero 1994). The mating behavior of F. verticillioides populations isolated mainly from cereals has been studied in several areas of the world (Chulze et al 2000;Cumagun 2007;Danielsen et al 1998;Leslie and Klein 1996;Mansuetus et al 1997;Reynoso et al 2006). To the best of our knowledge, no detailed information is currently available on the genetic structure of F. verticillioides populations in Italy as well as in other European maize growing areas, apart from the mating type assessment carried out by Moretti et al (2004) on 24 Italian strains, isolated from maize plants showing ear and stalk rot.…”

Genetic characteristics of Fusarium verticillioides from corn in the Philippines

“…Although the deviation of these results from the expected 1:1 ratio is of low significance, it is worthwhile to note that a larger population of 80 isolates of Fusarium from corn in the Philippines segregated at a Mendelian ratio of 1:1 (Cumagun 2008). Sexual reproduction is a major mechanism generating genotypic variation.…”

Mycotoxigenic Fungi and Mycotoxins in Agricultural Crop Commodities in the Philippines: A Review

“…Many of the regions that were surveyed by Pascual et al [25], including the Southern Mindanao—a hotspot for corn ear rot disease—were also at very high risk for fumonisin contamination according to the prediction made by Salvacion et al [12], particularly during the dry season [2]. Exacerbating the problem of fumonisin contamination is the occurrence of the sexual reproduction of F. verticillioides from the Philippines [34].…”