Biocontrol of cowpea aphid aphis craccivora(koch) using entomopathogenic fungi (Record no. 27860)

000 -LEADER
fixed length control field 03617nam a2200193Ia 4500
003 - CONTROL NUMBER IDENTIFIER
control field OSt
005 - DATE AND TIME OF LATEST TRANSACTION
control field 20220323142320.0
008 - FIXED-LENGTH DATA ELEMENTS--GENERAL INFORMATION
fixed length control field 140128s9999 xx 000 0 und d
082 ## - DEWEY DECIMAL CLASSIFICATION NUMBER
Classification number 632.6
Item number SAR/BI PG
100 ## - MAIN ENTRY--PERSONAL NAME
Personal name saranya s
245 ## - TITLE STATEMENT
Title Biocontrol of cowpea aphid aphis craccivora(koch) using entomopathogenic fungi
260 ## - PUBLICATION, DISTRIBUTION, ETC. (IMPRINT)
Place of publication, distribution, etc. Vellanikkara
Name of publisher, distributor, etc. Department of Agricultural Entomology, College of horticulture
Date of publication, distribution, etc. 2009
300 ## - PHYSICAL DESCRIPTION
Extent 60
502 ## - DISSERTATION NOTE
Degree type MSc
520 3# - SUMMARY, ETC.
Summary, etc. The present study entitled “Biocontrol of cowpea aphid, Aphis craccivora (Koch) using entomopathogenic fungi” was undertaken to identify the effective local isolates of entomopathogenic fungi (EPF) and to evaluate the pathogenicity of pure cultures and commercial formulations of Beauveria bassiana, Metarhizium anisopliae, Verticillium lecanii, Hirsutella thompsonii and local isolate on cowpea aphid, Aphis craccivora.

A survey was conducted at four locations of Thrissur district. During the survey, five fungal isolates were collected. Among the five isolates one pathogenic fungus, obtained from the Vellanikkara locality was identified as Cladosporium oxysporum. It is the first report from Kerala.

Laboratory bioassay studies were carried out with six different concentrations of B. bassiana, M. anisopliae, V. lecanii, H. thompsonii and C. oxysporum against the adults of A. craccivora. Among the five isolates tested, V. lecanii and H. thompsonii caused cent per cent mortality followed by B. bassiana with 96.66 per cent. It was revealed that V. lecanii and H. thompsonii showed higher virulence with the lowest LC50 value of 2.5x104 spores ml-1. At the highest concentration of 108 spores ml-1, the LT50 values ranged from 3.63 to 5.96 days in the different fungal isolates which was found increasing along with the decreasing concentrations.

The survival rate of nymphs was considerably reduced with in 24 hours after treatment. At the highest concentration (108 spores ml-1), all the isolates recorded less survival per cent of nymphs which ranged between 2.49 to 18.33 per cent. But even in the lower concentration (103 spores ml-1), H. thompsonii and B. bassiana exhibited low nymphal survivability (34.75 to 37.61%) as compared to other isolates.

Based on the bioassay studies a pot culture experiment was conducted to evaluate the efficacy of different fungal isolates against A. craccivora under field conditions. Among the different treatments, B. bassiana and V. lecanii @ 108 spores ml-1 and F. pallidoroseum @ 7x 106 spores ml-1 gave cent per cent mortality on 14th day after treatment. This was followed by the commercial formulations, Biopower and Biocatch (0.2%) and the chemical insecticide Malathion (0.05%) which recorded more than 90 per cent mortality.

The highest yield was obtained in plants treated with F. pallidoroseum @ 7x106 spores ml-1 which recorded the maximum number and weight of pods followed by V. lecanii and B. bassiana @ 108 spores ml-1. These treatments were statistically on par and were considerably increasing the yields upto 47.84, 47.14 and 45.10 per cent respectively.

From the study it is revealed that B. bassiana and V. lecanii @ 108 spores ml-1 were found to be as effective as the standard F. pallidoroseum @ 7x106 spores ml-1. These entomopathogenic fungi were found to be even more superior to the chemical insecticide, malathion based on the cumulative bioefficacy.

700 ## - ADDED ENTRY--PERSONAL NAME
Personal name Ushakumari R (Guide)
856 ## - ELECTRONIC LOCATION AND ACCESS
Uniform Resource Identifier http://krishikosh.egranth.ac.in/handle/1/5810044293
942 ## - ADDED ENTRY ELEMENTS (KOHA)
Source of classification or shelving scheme
Koha item type Theses
Holdings
Withdrawn status Lost status Source of classification or shelving scheme Damaged status Not for loan Permanent Location Current Location Shelving location Date acquired Full call number Barcode Date last seen Price effective from Koha item type
          KAU Central Library, Thrissur KAU Central Library, Thrissur Theses 2014-03-18 632.6 SAR/BI PG 172920 2014-03-18 2014-03-18 Theses
Kerala Agricultural University Central Library
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E-mail: librarian@kau.in
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