Effects of carbon concentration and carbon to nitrogen ratio on the growth and sporulation of several biocontrol fungi.

Key Laboratory of Systematic Mycology and Lichenology, Institute of Microbiology, Chinese Academy of Sciences, PO Box 2714, Beijing 100080, PR China.
Mycological Research (Impact Factor: 2.81). 02/2007; 111(Pt 1):87-92. DOI: 10.1016/j.mycres.2006.07.019
Source: PubMed

ABSTRACT Effects of carbon concentration and carbon to nitrogen (C:N) ratio on six biocontrol fungal strains are reported in this paper. All fungal strains had extensive growth on the media supplemented with 6-12 gl(-1) carbon and C:N ratios from 10:1 to 80:1, and differed in nutrient requirements for sporulation. Except for the two strains of Paecilomyces lilacinus, all selected fungi attained the highest spore yields at a C:N ratio of 160:1 when the carbon concentration was 12 gl(-1) for Metarhizium anisopliae SQZ-1-21, 6 gl(-1) for M. anisopliae RS-4-1 and Trichoderma viride TV-1, and 8 gl(-1) for Lecanicillium lecanii CA-1-G. The optimal conditions for P. lilacinus sporulation were 8 gl(-1) carbon with a C:N ratio of 10:1 for M-14 and 12 gl(-1) carbon with a C:N ratio of 20:1 for IPC-P, respectively. The results indicated that the influence of carbon concentration and C:N ratio on fungal growth and sporulation is strain dependent; therefore, consideration for the complexity of nutrient requirements is essential for improving yields of fungal biocontrol agents.

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