COMPARATIVE EVALUATION OF SOME BOTANICALS AGAINST KHAPRA BEETLE TROGODERMA GRANARIUM EVERTS (COLEOPTERA: DERMESTIDAE) ON STORED GROUNDNUTS
COMPARATIVE EVALUATION OF SOME BOTANICALS AGAINST KHAPRA BEETLE TROGODERMA GRANARIUM EVERTS (COLEOPTERA: DERMESTIDAE) ON STORED GROUNDNUTS
No Thumbnail Available
Date
2007-02
Authors
MUSA, ABDULRASAK KANNIKE
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Khapra beetle, Trogoderma granarium Everts, is a serious storage insect pest
of cereals and legumes in the tropical and sub-tropical regions of the world.
The study was carried out in the laboratory at prevailing temperature
(25±50C) and relative humidity (65±5%). Six improved groundnut varieties,
which include SAMNUT 14, SAMNUT 17, SAMNUT 18, SAMNUT 21,
SAMNUT 22 and SAMNUT 23 were examined for their susceptibility to T.
granarium. Susceptibility of these varieties to the dermestid was determined
with respect to kernel damage assessment, mean kernel weight loss and total
larvae population. The food preference of the T. granarium larvae for the
groundnut varieties after six months storage period was also investigated.
SAMNUT 22 variety was the most susceptible while the least susceptible
was SAMNUT 17. Further preliminary laboratory experiments involved
screening of nine indigenous plant powders (leaves/seeds) against T.
granarium larvae. Methanol extracts of five promising plant powders of
Ricinus communis Linnaeus, Hyptis suaveolens Poit., Annona senegalensis Pers.,
Xylopia aethiopica Dunal and Khaya senegalensis Desr. were assayed for their
effects on adult mortality and larval survival of T. granarium. Adult
mortality and survival of larvae of T. granarium were significantly (P<0.05)
different with increased all doses of crude extracts compared with the
control. Adult mortality increased with the concentration of crude extracts
and the duration of exposure of the insects on the treated groundnut kernels.
The crude extracts were almost similar in their effectiveness. However, the
potency of these extracts decreased rapidly due to volatilization. The five
botanicals have good potentials as post harvest insect control agents, killing
89.0% of the insect three days after treatment at 3.0 ml per 50 grams kernels.
R. communis crude extract has detectable harm on the kernels in causing
discolouration and wrinkle. The most preferred of the treatment was the
groundnut kernel coated with X. senegalensis crude extract. These results
showed that the crude extracts of these plants may be exploited for
Trogoderma control in stored products. Chemical analysis including infrared
spectroscopy revealed the presence of amines, amides, aldehydes and
ketone as the organic components in the test plants. Flavonoid was
identified as a constituent of all the test plants except K. senegalensis. The
results confirmed that X. aethiopica, in addition contained saponins, tannins,
polyphenols,, steroids, glycosides and alkaloids. All the test plants contained
polyphenols. In addition, alkaloids were detected in H. suaveolens. The
chemical components detected in K. senegalensis include saponins. These
components may be toxic to T. granarium. The results suggested that
powders and crude extracts of the test plants could be used to suppress the
menace of T. granarium.
Description
A DISSERTATION SUBMITTED TO THE
POSTGRADUATE SCHOOL,
AHMADU BELLO UNIVERSITY, ZARIA
NIGERIA
IN PARTIAL FULFILLMENT OF THE REQUIREMENTS
FOR THE AWARD OF
DOCTOR OF PHILOSOPHY IN
CROP PROTECTION
DEPARTMENT OF CROP PROTECTION
AHMADU BELLO UNIVERSITY, ZARIA
NIGERIA.
Keywords
COMPARATIVE,, EVALUATION,, BOTANICALS,, KHAPRA BEETLE,, TROGODERMA,, GRANARIUM EVERTS,, COLEOPTERA,, DERMESTIDAE,, STORED,, GROUNDNUTS