ISOLATION AND CHARACTERIZATION OF ENTOMOPATHOGENIC ...

More documents

Recommendations

Info

2.8 COMPATIBILITY <strong>ENTOMOPATHOGENIC</strong> FUNGI WITH AGROCHEMICALS Compatibility of entomopathogenic fungi with pesticides used in commercial crop protection systems is critical, if these fungi are to be utilized for insect control. Since many fungicides have broad spectra of activity, the suppression of entomopathogenic fungi by fungicides is of particular concern. Though there are many methods of evaluating fungicidal activity, most studies of entomopathgenic fungi, have used inhibition of growth in liquid or on solid media as the primary criterion (Roberts and Campbell, 1977). Soper et al. (1974) tested the efficacy of fungicides on growth of several species of entomopathogens in agar media and found that all were inhibitory. Growth of B. bassiana, a member of the moniliales and pathogen of several insect pests was inhibited by fungicide in solid and in liquid media. Teddeur (1981) evaluated six fungicides against the entomopathogenic fungi Beauveria bassiana (Balsamo) Vuilemin and Metarhizium anisopliae, both of which attack the pecan weevil, Curulio caryae. Triphenyltin hydroxide was the most toxic fungicide to both pathogens, followed by benomyl, methyl-1-(butylcarbamoyl)-2-benzimidazolecarbamate, zineb, zince ethylenebis (dithiocarbamats) and dodine, n-dodecylaquanidine acetate. Sulphur and denocap were the least toxic. Four fungicides used commercially for control of foliar diseases of potato were evaluated in vitro and under field conditions of effects on survival of spores of Beauveria bassiana, a pathogen of the Colorado potato beetle, Leptinotarsa decemlineata. Mancozeb, the most detrimental of the fungicides, substantially reduced the survival under any of the conditions examined (Loria et al., 1983). Metarhizium anisopliae and Beauveria bassiana are both compatible with many commonly used pesticides and are not toxic to human beings (Burges, 1981). M. anisopliae is soil borne fungus and infects over 200 hosts indicating a need to evaluate compatibility with non-targets, with pesticides and natural enemies (Gardner et al., 1998). Most importantly, entomopathogenic V. lecanii strains have been found non-pathogenic to plants and humans (Burges, 1981). Recommended concentrations of insecticides viz., fenitrothion, monocrotophos and phosphomidon and the fungicides like ziram, foltaf, dithane Z-78, chlorothalonil, captan and wettable sulphur were found safe to the fungus N. rileyi. Silva et al. (1993) conducted experiments to evaluate the effect of endosulfan (175 g a.i.), prefenophos (100 g a.i.), trichlorfon (400 g a.i.) and permethrin (12.5 g a.i.), on sporulation in vitro on SMAY medium. Sporulation was totally inhibited by profenophos and endosulfan, while trichlorfon reduced the conidial production. There was no significant difference between permethrin and untreated control. Influence of nine insecticides on the natural infection of A. gemmatalis by N. rileyi were studied by Barbosa et al. (1997). The effects of trichlorfon and chlorpyriphos did not differ from the untreated control. Baculovirus anticarsia, diflebenzuron, endosulfan, methamidophos, monocrotophos, methyl parathion and thiodicarb showed similar performance and caused significant decrease in the percentage of mycosed larvae. Tang and Hou (1998) evaluated five fungicides, eight insecticides and nine herbicides commonly used in maize fields, for their inhibition to conidial germination of N. rileyi by paper disc method. Among them, maneb and propineb (fungicides) were highly inhibitory to the fungus while, insecticides and herbicides examined did not affect the conidial germination significantly. Carbendazim was found to be most detrimental to the fungus inhibiting 75.85 per cent growth, while endosulfan, chlorpyriphos, carbaryl, cypermethrin and neem based insecticides caused 60.81, 60.25, 37.23, 22.48 and 11.23 per cent growth inhibition, respectively (Kulkarni, 1999).
Gopalkrishnan and Mohan (2000) tested seven insecticides and seven fungicides which are commonly used for the control of pests and diseases of tomato for their inhibitory effect on germination of conidia of N. rilei at three (low, normal and high) concentrations in vitro. They concluded that, monocrotophos, phosphomedon and dimethoate were safe to the mycopathogen at all the three concentrations. While quinalphos, carbaryl, endosulfan and fenvalerate were highly detrimental to the fungus at higher concentration. Among the fungicides, captafol, zineb, chlorothalonil, fosetyl Al and ziram were safe to the fungus at all the concentrations evaluated. Captan and sulphur on the other hand, though allowed conidial germination at low and normal concentrations caused total inhibition at higher concentrations.
Page 1 and 2: ISOLATION AND CHARACTERIZATION OF E
Page 3 and 4: Chapter No. I INTRODUCTION C O N T
Page 5 and 6: Contd….. Table No. Title 14. Spor
Page 7 and 8: Contd….. Table No. Title 39. Per
Page 9 and 10: Plate No. LIST OF PLATES Title 1. M
Page 11 and 12: I.INTRODUCTION The increased use of
Page 13 and 14: II. REVIEW OF LITERATURE The variou
Page 15 and 16: The entomopathogenic fungi so far i
Page 17 and 18: Table 1. Contd….. Sl. No. Insect
Page 19 and 20: Milner et al. (2002) studied the ef
Page 21 and 22: 25°C for sporulation and biomass p
Page 23: Pathogencity of various strains/iso
Page 27 and 28: necessary serial dilutions under ph
Page 29 and 30: Sl. No. Table 2. Details of differe
Page 31 and 32: 3.9 EVALUATION OF DIFFERENT FORMULA
Page 33 and 34: Fig. 1. Mycopathogens of insect pes
Page 35 and 36: Table 5. Contd….. Month/s visited
Page 37 and 38: Table 5. Contd….. Month/s visited
Page 39 and 40: Table 5. Contd….. Mycosis noticed
Page 41 and 42: Totally eight isolates of N. rileyi
Page 43 and 44: Metarhizium anisopliae Vertucillium
Page 45 and 46: Ma 1 (Dharwad) Ma2 (Dharwad) Ma 3 (
Page 47 and 48: Table 8. Mortality caused by the is
Page 49 and 50: Helicoverpa armigera Dimond Black M
Page 51 and 52: Plate 5. The moratality of Hlelicov
Page 53 and 54: Table 11. Total biomass production
Page 55 and 56: Table 12. Total biomass production
Page 57 and 58: Table 14. Sporulation of Metarhiziu
Page 59 and 60: Mean spore yield x 10 8 /g 25 20 15
Page 61 and 62: Among the non-grain substrates, the
Page 63 and 64: Mean spore yield x 10 4 /g 35 30 25
Page 65 and 66: Sl. No. Table 19. Effect of fungici
Page 67 and 68: Per cent inhibition 100 90 80 70 60
Page 69 and 70: Sl. No. Table 21. Effect of insecti
Page 71 and 72: Out of nine insecticides, endosulfa
Page 73 and 74: Sl. No. Table 23. Effect of weedici
Page 75 and 76:
Days after storage Table 25. Persis
Page 77 and 78:
Table 26. Survival of Metarhizium a
Page 79 and 80:
Table 28. Survival of Metarhizium a
Page 81 and 82:
Sl. No. Table 29. Survival of Metar
Page 83 and 84:
Sl. No. Table 30. Survival of Metar
Page 85 and 86:
Per cent germination 90 80 70 60 50
Page 87 and 88:
Sl. No. Table 33. Survival of Verti
Page 89 and 90:
Page 91 and 92:
Page 93 and 94:
4.9 PATHOGENICITY OF Verticillium l
Page 95 and 96:
Sl. No. Table 39. Per cent mortalit
Page 97 and 98:
Culture grown on rice grains Harves
Page 99 and 100:
Tr. No. Table 41. Per cent reductio
Page 101 and 102:
Tr. No. Table 43. Per cent reductio
Page 103 and 104:
The fungal spray at higher dosage (
Page 105 and 106:
Table 46. Effect of wild types and
Page 107 and 108:
The hyphal and conidial characters
Page 109 and 110:
In an earlier experiment, bagasse w
Page 111 and 112:
M. anisopliae exhibited rapid reduc
Page 113 and 114:
higher mortality of aphids. The com
Page 115 and 116:
14. Oil formulations proved better
Page 117 and 118:
CHARNLEY, A.K. AND ST. LEGER, R.J.,
Page 119 and 120:
IGNOFFO, C.M., MARSTON, N.L., HOSTE
Page 121 and 122:
MULLER, E.J., 2000, Control of the
Page 123 and 124:
ST LEGER, R.J., BUTT, T.M., STAPLES
Page 125 and 126:
APPENDIX I Mean monthly weather dat
Page 127 and 128:
Maharashtra Association for the Cul
Page 129:
ISOLATION AND CHARACTERIZATION OF E
show all

ISOLATION AND CHARACTERIZATION OF ENTOMOPATHOGENIC ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?