Production of thermotolerant entomopathogenic fungal conidia on millet grain.
Thermotolerance of entomopathogenic (insect-killing) fungi should be seriously considered before industrialization. This work describes the feasibility of millet grain as a substrate for production of thermotolerant Beauveria bassiana (Bb) GHA and ERL1170 and Metarhizium anisopliae (Ma) ERL1171 and ERL1540 conidia. First, conidial suspensions of the Bb isolates, produced on millet grain in polyethylene bags, were exposed to five temperatures (43-47 °C) at 15-min intervals for up to 120 min (experiment I). Agar-based quarter-strength (¼) Sabouraud dextrose agar supplemented with yeast extract (SDAY) and whey permeate media served as controls. Millet-grain-based culture was superior in producing the most thermotolerant Bb conidia, followed by whey permeate agar and ¼SDAY-based cultures. Secondly, to compare the thermotolerance of conidia produced at the same conditions, the Bb isolates were then produced on agar-based millet powder medium, with ¼SDAY and whey permeate agar media as controls, and the two Ma isolates were added (experiment II). They were then exposed to the same temperatures as above. More thermotolerant Bb and Ma conidia were produced on millet powder agar than on whey permeate agar and ¼SDAY overall. These results suggest that millet grain can be used as a substrate to produce thermotolerant conidia in a mass production system.
Kim
Jae Su
JS
Entomology Research Laboratory, Plant and Soil Science, University of Vermont, 661 Spear Street, Burlington, Vermont 05405-0105, USA.
Kassa
Adane
A
Skinner
Margaret
M
Hata
Teri
T
Parker
Bruce L
BL
D000362:Agar; D052982:Beauveria / Q000502:physiology*; D003470:Culture Media; D002523:Edible Grain / Q000382:microbiology; D052981:Metarhizium / Q000502:physiology*; D050296:Microbial Viability; D008897:Panicum / Q000382:microbiology*; D013172:Spores, Fungal / Q000254:growth & development; D013696:Temperature
D003470:Culture Media; D000362:Agar
Microbiology (Reading). 1995 May;141 ( Pt 5):1109-1115
7773406
Microbiol Rev. 1995 Sep;59(3):506-31
7565416
Mol Cell. 1998 Apr;1(5):639-48
9660948
J Cell Biol. 1986 Aug;103(2):321-5
2426277
Mycol Res. 2008 May;112(Pt 5):583-91
18396025
J Invertebr Pathol. 2005 Mar;88(3):181-9
15955335
Plant Physiol. 1999 Sep;121(1):45-52
10482659
Mycol Res. 2005 Mar;109(Pt 3):319-25
15912949
Appl Environ Microbiol. 2005 Sep;71(9):5260-6
16151112
Microbiology (Reading). 2001 Aug;147(Pt 8):2255-2264
11496002
Can J Microbiol. 1997 Jun;43(6):569-76
9226876
Eukaryot Cell. 2003 Aug;2(4):690-8
12912888
Appl Environ Microbiol. 1996 Jul;62(7):2435-42
16535354
Trends Biotechnol. 2002 Oct;20(10):420-5
12220904
Lett Appl Microbiol. 2006 Sep;43(3):331-5
16910941
Appl Microbiol Biotechnol. 2005 Sep;68(4):481-8
15731900
Trends Biochem Sci. 1995 Jan;20(1):3-10
7878741
Microbiology (Reading). 2004 Apr;150(Pt 4):1095-1101
15073319
Mycol Res. 2008 Nov;112(Pt 11):1362-72
18938068
Mol Microbiol. 1997 May;24(4):687-95
9194697
Mycopathologia. 2011 Jan;171(1):67-75
20571913
FEBS Lett. 1997 Aug 4;412(3):615-20
9276477
EMBO J. 1992 Jun;11(6):2357-64
1600951
J Ind Microbiol Biotechnol. 2010 Apr;37(4):419-23
20157761
Mikrobiologiia. 2005 May-Jun;74(3):293-304
16119841
Biotechnol Prog. 2004 Jan-Feb;20(1):248-54
14763849
J Insect Sci. 2004;4:38
15861253
Biochemistry (Mosc). 2002 May;67(5):511-9
12059769
Appl Environ Microbiol. 2004 Jan;70(1):129-36
14711634
J Invertebr Pathol. 2008 May;98(1):69-78
18096184
Annu Rev Biochem. 1986;55:1151-91
2427013