| Verticillium lecanii (Zimmerman) Viegas is worldwide entomogenous fungus, mainly infesting whitefly and aphis, Homoptera. It has been used in greenhouse pest control. For developing this fungus, the fermentation biology, fermentation conditions and application of this strain CA0319 of Verticillium lecanii from China were investigated. The nutrition requirement of this fungus had been made clear in this research. The test results, especially about the amino acid, could be used in industry fermentation. It was economical significant to industry production of this fungus.With comparing and screening tests, some new media prescriptions for high sporulation in liquid and solid cultivation were got. The fermentation characteristic and kinetics of this strain were revealed. A liquid fermentation technology was established that raised the fermenting level to a new high level. The details are as follows:Fermentation Biology: Tests showed that the conidia of this strain could germinate and grow quickly and sporulate highly. The best ratio of C/N was 20:1. The best concentration of C was Imol/L. Among the common sugar materials, the best for growth and sporulation was sucrose, starch soluble and maltose. Among some representative sugar, the D-Cellobiose and D-Trehalose were best for growth and absorption. It showed this strain was strong to digest diose. Among N nutrition resource, the best for sporulation was bean peptone and beef extract peptone. Among the common amino acids the best for sporulation was L-Phenylalanine followed by glutamic acid, glycine, threonine.Absence of the macroelements ( K,P,S,Mg,Fe) could cause a high reducing percentage to sporulation. The reducing percentage of K,P,S was over 99%. The reducing percentage of Mg and Fe are 89% and 50% respectively. In the solid culture the sequence of reducing sporulation was P>K>Mg>S>Fe. The scale of reducing sporulation was from 17% to 97%.Microelement Zn at a concentration of l-100ug/mL could increase the sporulation significantly. Higher concentration than that could suppress the growth and sporulation. Microelement Al at 1-50g/mL could increase thegrowth and sporulation. Microelement Mn at a concentration of 1-150 g/mL could increase the mycelial growth and sporulation. The best concentration is 50 g/mL. Microelement Mn at the concentration of lppm-150g/mL also could increase the strain growth. The best concentration is 50 g/mL. Microelement Ag suppresses the fungus growth. Microelement Ni at 1 g/mL had the role of increasing. The higher concentration than that had significant suppressing role. Microelement Mo at the concentration of 1-25 g/mL could increase the growth. The best concentration was 25 g/mL. The higher concentration than that could cause a suppressing impact. Nicotinic acid at a concentration of 10 g/mL could cause a increase of 33.6%. Vitamin B6 could cause an increase of 20.2%.Characteristic and technology of fermentation: In the shaker cultivation, referring to the results of orthogonal test, synthetically designing new cultivation conditions, under the conditions of initial sugar concentration of medium of 15-30g/L, flask loading capacity 12%,seeding volume 10%, temperature 25 C in first 24h,23 C in late 24-60h, shaking speed 250rpm, the experimemt result showed that the delayed period of fungus growth was be shortened, and the best fermenting termination was moved backward, and the yield of sporulation was increased 2.5 times.Fermentor cultivation: In 5L fermentor(NBS), under the conditions of sugar concentration 2.5%, seeding volume 8%,temperature 25-23 C, DO above 15%, it resulted in a similar yield of 2.2 + 109 /mL to last test with seeding volume 1%. The best fermenting process only spent 33 hours, being shortened 20 hours.In 16L fermentor, the test showed that lack of oxygen could affect the mycelial growth in the first period of fermentation, and affected the sporulation in the late period. The DO should keep above 40%. The pH should be raised when it dropped to 2.8. The fermentation period with seeding bla...
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