Morphology and mycelial growth rate of Pleurotus spp. strains from the Mexican mixtec region

Revista de microbiologia

Valencia del Toro, G.¹  Ramírez-Carrillo, R.²  Robles-Martínez, F.³  Guadarrama-Mendoza, P.C.⁴ 

[1] Instituto Politécnico Nacional, México D.F., México;Universidad Nacional Autónoma de México, México D.F., México;Universidad Nacional Autónoma de México, Tlalnepantla, México;Universidad Tecnológica de la Mixteca, Oaxaca, México

关键词: Pleurotus;    mycelial growth;    mycelial morphology;    hybrid strains;    monokaryotization.;   

DOI  :  10.1590/S1517-83822014000300016

学科分类：农业科学（综合）

来源: Sociedade Brasileira de Microbiologia / Brazilian Society for Microbiology

【 摘 要 】

Two native Pleurotus spp. strains (white LB-050 and pale pink LB-051) were isolated from rotten tree trunks of cazahuate (Ipomoea murucoides) from the Mexican Mixtec Region. Both strains were chemically dedikaryotized to obtain their symmetrical monokaryotic components (neohaplonts). This was achieved employing homogenization time periods from 60 to 65 s, and 3 day incubation at 28 °C in a peptone-glucose solution (PGS). Pairing of compatible neohaplonts resulted in 56 hybrid strains which were classified into the four following hybrid types: (R1-nxB1-n, R1-nxB2-1, R2-nxB1-n and R2-nxB2-1). The mycelial growth of Pleurotus spp. monokaryotic and dikaryotic strains showed differences in texture (cottony or floccose), growth (scarce, regular or abundant), density (high, regular or low), and pigmentation (off-white, white or pale pink). To determine the rate and the amount of mycelium growth in malt extract agar at 28 °C, the diameter of the colony was measured every 24 h until the Petri dish was completely colonized. A linear model had the best fit to the mycelial growth kinetics. A direct relationship between mycelial morphology and growth rate was observed. Cottony mycelium presented significantly higher growth rates (p < 0.01) in comparison with floccose mycelium. Thus, mycelial morphology can be used as criterion to select which pairs must be used for optimizing compatible-mating studies. Hybrids resulting from cottony neohaplonts maintained the characteristically high growth rates of their parental strains with the hybrid R1-nxB1-n being faster than the latter.

【 授权许可】

CC BY-NC