Importance of Different Pathways for Maize Kernel Infection by Fusarium moniliforme

Abstract

The relative importance of several infection pathways (silks, stalks, and seed) leading to kernel infection of maize hybrids by Fusarium moniliforme was investigated in field experiments in 1993 and 1994. Systemic movement of specific fungal strains within plants was detected by using vegetative compatibility as a marker. Transmission of F. moniliforme from inoculated seed to stalks and developing kernels was detected in two of three field experiments; the seed-inoculated strain was detected in kernels on approximately 10% of ears. The percentage of kernels infected with the seed-inoculated strain ranged from 0 to 70%, with a mean of 0 to 2.5% (0 to 8.3% of F. moniliforme-infected kernels). Other pathways to kernel infection were more effective than seed transmission and systemic infection. F. moniliforme strains inoculated into the crowns and stalks of plants were found throughout the stalks and in up to 95% of the kernels in individual plants. Infection through the silks was clearly the most effective pathway to kernel infection. This was the only inoculation method that significantly increased overall incidence of F. moniliforme infection in kernels; the silk-inoculated strain infected up to 100% of the kernels in individual ears, with a treatment mean as high as 83.7% of kernels. When plants were silk-inoculated, the percentage of kernels infected by other F. moniliforme strains from the seed or stalk was reduced, apparently due to competition among strains. This study provides evidence that systemic development of F. moniliforme from maize seed and stalk infections can contribute to kernel infection, but silk infection is a more important pathway for this fungus to reach the kernels.

Fumonisins in Maize: Can We Reduce Their Occurrence?

“…In many cases, its presence is ignored because it is not causing visible damage. Symptomless infection can exist throughout the plant, and seed-transmitted strains of the fungus can develop systemically to infect the kernels (20,35). By most definitions, this relationship can be referred to as endophytic (52).…”

“…F. moniliforme is seedborne and seedtransmitted (31). This phase of the disease cycle has been associated primarily with seedling disease; the role of seed transmission in stalk and kernel rot is not as clear, but strains from the seed can be found throughout the plant in some cases (20,35). Seed can be infected with no detrimental effects on the seedlings (21,31).…”

Impacto das Fumonisinas, Aflatoxinas e Ocratoxina A na Avicultura

“…Durante a colheita, o fungo BBR -Biochemistry and Biotechnology Reports Jan./Jun., v.2, n.1, p. 68-88, 2013 Review / Resenha pode ser encontrado tanto nas plantas como nos restos das culturas. Por outro lado, F. verticillioides pode também colonizar o milho de forma assintomática, e, neste caso, não causa doenças visíveis, relação esta denominada de endofítica (MUNKVOLD; DESJARDINS, 1997;McGEE;CARLTON, 1997;SIEGAL;LATCH;JOHNSON, 1987). A contaminação de milho por F. verticillioides ocorre principalmente por meio da infecção dos estigmas por conídios carreados pelo ar ou água.…”

“…A contaminação de milho por F. verticillioides ocorre principalmente por meio da infecção dos estigmas por conídios carreados pelo ar ou água. No entanto, a doença pode se estabelecer via contaminação da semente chegando à espiga e grãos por meio da circulação sistêmica caulinar; pela infecção da raiz atingindo os grãos através do colmo e espiga; e via ferimentos causados por insetos, os quais, também podem atuar como vetores de inóculo (MUNKVOLD; McGEE; CARLTON, 1997;DRAGACCI, 2004).…”

Influence of growing Bt maize on Fusarium infection and mycotoxins content - a review

“…can infect maize during emergence and after the plant has been damaged by birds (Reid 1999), and in some other cases during the vegetation period. Maize kernels can be infected by conidia growing through stigmata with styles which are very sensitive during the first six days after their emergence (Reid & Hamilton 1996;Munkvold et al 1997b). The infection via the stigmata is important for F. verticillioides and probably also for F. proliferatum and F. subglutinans (Munkvold et al 1997a).…”