Reji G V
Management Of The American Serpentine Leaf Miner Liriomyza Trifolii (Burgess) Dietars On Cowpea,vigna Unguiculata(L.) Walp - Vellayani Department of Agricultural Entomology, College of Agriculture 2002
Survey conducted in Kailiyoor panchayat of Thiruvananthapuram
district revealed that Liriomyza trifol ii caused maximum damage to
cowpea at the reproductive phase of the crop III summer. Raising
susceptible varieties, applying high doses of nitrogen and frequent use of
insecticides were noted to intensify the pest incidence. The weeds,
Achyranthus aspera, Amaranthus viridis, Cleome viscosa, Cleome
monophylfa, Heliotropium indicum, Physalis minima and Desmodium
gyrans were identified as host plants of the pest. Seven larval parasitoids
were recorded of which Chrysonotomyia rexia and Asecodes sp. were
predominant.
Twenty accessions of ccwpea including trailing and bush types
were screened in the laboratory for resistance to L. trifolii. Accessions
of trailing type were more susceptible to the pest. VU-12 was least
susceptible among the trailing type while Sharika and Vyjayanthi were
highly susceptible. Among the bush type, VU-4, VU-6, VU-3 and Arka
Garima were less susceptible.
Four plant oils and four synthetic insecticides when evaluated in
the laboratory at two doses along with neem oil (2.5 per cent) and
dimethoate (0.05 per cent) showed no significant diffe. ence in efficacy
between the doses. Neem oil, marotti oil and ilIupai oil at 2.5 per cent
and abamectin, 0.003 per cent, thiamethoxam, 0.02 per cent and
profenophos, 0.025 per cent were found to be effective in controlling the
pest.
All the treatments reduced the pest infestation significantly in the
field. Abamectin, 0.003 per cent was significantly superior. Neem oil,
marotti oil and illupai oil 2.5 per cent also reduced pest infestation.
Considering the cost and safety to the natural enemies, the oils were
found more advantageous to the farmers.
Based on the results, cultivation of the tolerant accession VU -12
111 endemic areas, destruction of weed host plants, judicious application
of nitrogen and need based application of neem oil / marotti oil / illupai
oil at 2.5 per cent can be recommended for inclusion in rPM strategies of
L. trifolii.
632.6 / REJ/MA
Management Of The American Serpentine Leaf Miner Liriomyza Trifolii (Burgess) Dietars On Cowpea,vigna Unguiculata(L.) Walp - Vellayani Department of Agricultural Entomology, College of Agriculture 2002
Survey conducted in Kailiyoor panchayat of Thiruvananthapuram
district revealed that Liriomyza trifol ii caused maximum damage to
cowpea at the reproductive phase of the crop III summer. Raising
susceptible varieties, applying high doses of nitrogen and frequent use of
insecticides were noted to intensify the pest incidence. The weeds,
Achyranthus aspera, Amaranthus viridis, Cleome viscosa, Cleome
monophylfa, Heliotropium indicum, Physalis minima and Desmodium
gyrans were identified as host plants of the pest. Seven larval parasitoids
were recorded of which Chrysonotomyia rexia and Asecodes sp. were
predominant.
Twenty accessions of ccwpea including trailing and bush types
were screened in the laboratory for resistance to L. trifolii. Accessions
of trailing type were more susceptible to the pest. VU-12 was least
susceptible among the trailing type while Sharika and Vyjayanthi were
highly susceptible. Among the bush type, VU-4, VU-6, VU-3 and Arka
Garima were less susceptible.
Four plant oils and four synthetic insecticides when evaluated in
the laboratory at two doses along with neem oil (2.5 per cent) and
dimethoate (0.05 per cent) showed no significant diffe. ence in efficacy
between the doses. Neem oil, marotti oil and ilIupai oil at 2.5 per cent
and abamectin, 0.003 per cent, thiamethoxam, 0.02 per cent and
profenophos, 0.025 per cent were found to be effective in controlling the
pest.
All the treatments reduced the pest infestation significantly in the
field. Abamectin, 0.003 per cent was significantly superior. Neem oil,
marotti oil and illupai oil 2.5 per cent also reduced pest infestation.
Considering the cost and safety to the natural enemies, the oils were
found more advantageous to the farmers.
Based on the results, cultivation of the tolerant accession VU -12
111 endemic areas, destruction of weed host plants, judicious application
of nitrogen and need based application of neem oil / marotti oil / illupai
oil at 2.5 per cent can be recommended for inclusion in rPM strategies of
L. trifolii.
632.6 / REJ/MA