Genetic analysis of growth, morphology and pathogenicity in the F(1) progeny of an interspecific cross between Fusarium circinatum and Fusarium subglutinans.

Fusarium circinatum and Fusarium subglutinans are two distinct species in the Gibberella fujikuroi species complex. A genetic linkage map produced from an interspecific cross between these species was used to identify quantitative trait loci (QTLs) associated with variation in mycelial growth and morphology of colony margins (CMs) in the 94 F(1) progeny. Mycelial growth was assessed by measuring culture size at 25°C and 30°C, while CM morphology was characterized in the parents and assessed in their F(1) progeny. In order to test the pathogenicity of the progeny, Pinus patula seedlings were inoculated and lesion lengths were measured after 3weeks. Seven putative QTLs were associated with mycelial growth, three for growth at 25°C and four at 30°C. One highly significant QTL (P<0.001) was present at both growth temperatures. For CM morphology, a QTL was identified at the same position (P<0.001) as the QTL responsible for growth at the two temperatures. The putative QTLs accounted for 45 and 41% of the total mycelial growth variation at 25°C and 30°C, respectively, and for 21% of the variation in CM morphology. Only one of the 94 F(1) progeny was pathogenic on P. patula seedlings. This observation could be explained by the genetic constitution of this F(1) isolate, namely that ∼96% of its genome originated from the F. circinatum parent. This F(1) individual also grew significantly faster at 25°C than the F. circinatum parent (P<0.05), as well as more rapidly than the average growth for the remaining 93 F(1) progeny (P<0.05). However, no association was found between mycelial growth and pathogenicity at 25°C. The highly significant QTL associated with growth at two temperatures, suggests that this is a principal genomic region involved in mycelial growth at both temperatures, and that the same region is also responsible for CM morphology.

De Vos L ，van der Nest MA ，van der Merwe NA ，Myburg AA ，Wingfield MJ ，Wingfield BD ... -  《Fungal Biology》

Complete genetic linkage maps from an interspecific cross between Fusarium circinatum and Fusarium subglutinans.

De Vos L ，Myburg AA ，Wingfield MJ ，Desjardins AE ，Gordon TR ，Wingfield BD ... -  《FUNGAL GENETICS AND BIOLOGY》

The influence of environmental factors on growth and interactions between Embellisia allii and Fusarium oxysporum f. sp. cepae isolated from garlic.

Embellisia allii results in the formation of a bulb canker and black soot on the surface of different alliums and it has been frequently detected on garlic bulbs together with the spoilage fungus, Fusarium oxysporum f. sp. cepae, which causes bulb basal plate rot. In this study, the influence of water activity (a(w)) and temperature on mycelial growth of E. allii and F. oxysporum f. sp. cepae, conidial size and sporulation of E. allii, interactions between E. allii and F. oxysporum f. sp. cepae, Index of Dominance (I(D)), and in situ virulence on garlic were examined. Mycelial growth of E. allii was optimal (5.97 mm/day) at 0.995 a(w) and 25 degrees C, slower at 30 degrees C. However, almost no growth occurred at 0.937 a(w)/30 degrees C. F. oxysporum f. sp. cepae grew faster than E. allii, (6.3-7.4mm/day) at 30 degrees C. Interactions between E. allii and F. oxysporum f. sp. cepae were influenced by a(w) and temperature. Sporulation of E. allii was more abundant on PDA than on MEA, especially at high a(w) (0.995) and low temperature (20 degrees C), but almost no sporulation occurred at 30 degrees C regardless of nutritional medium or a(w) level. The spore length of E. allii was longer on PDA than MEA, and was significantly influenced by water availability. F. oxysporum f. sp. cepae was competitive against E. allii and had a higher I(D) value in comparison with E. allii especially at a higher temperature (30 degrees C). In situ virulence tests showed that E. allii was weakly virulent on the garlic bulb cloves while that of F. oxysporum f. sp. cepae was highly dependent on a(w).

Lee HB ，Magan N 《-》

Genetic linkage between growth rate and the intersterility genes S and P in the basidiomycete Heterobasidion annosum s.lat.

Olson A 《mycological research》

Characterization of Fusarium circinatum from Pinus spp. in northern Spain.

Pérez-Sierra A ，Landeras E ，León M ，Berbegal M ，García-Jiménez J ，Armengol J ... -  《mycological research》