Diversity of Aphidophagous Natural Enemy Guild in Maize
Loading...
Date
2014
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
MPUAT, Udaipur
Abstract
The present investigation on, “Diversity of aphidophagous natural enemy guild in
maize” was carried out at the Instructional Farm, Rajasthan College of Agriculture,
Udaipur during summer (zaid) (April to July, 2013) and kharif (July to October, 2013)
seasons with the objectives to study the diversity of aphids of maize and their natural
enemies and evaluate the predation potential of major insect groups of the aphidophagous
guild in the field and laboratory. The major aphid recorded on maize was Rhopalosiphum
maidis (Fitch) and on cowpea (as an intercrop) was Aphis craccivora (Koch). Among the
aphidophagous natural enemy guild, the major insect groups included coccinellids (C.
septempunctata, Cheilomenes sexmaculatus, B. suturalis and I. cincta: Coccinellidae,
Coleoptera); lygaeid bug (Geocoris sp.: Lygaeidae, Hemiptera,); rove beetle [Paederus
fuscipes Curtis: Staphylindae, Coleoptera] and syrphid flies (Ischiodon sp.: Syrphidae,
Diptera; being dominant). The seasonal mean population of aphids was higher during
kharif season crop (369.09/plant) than during the summer season (291.26/plant).
Likewise, the seasonal mean population of the natural enemy guild per plant was
relatively more during kharif season being 8.56 (coccinellids), 3.76 (Geocoris sp.), 3.14
(P. fuscipes) and 2.41 (syrphid flies); whereas, in summer (jhaid) season the
corresponding values were 7.78 (coccinellids), 3.60 (Geocoris sp.), 2.87 (P. fuscipes) and
1.89 (syrphid flies). Exclusion of the ground dwelling aphidophagous predators resulted
into significantly more aphid predation (99.75%) than when aerial aphidophagous
predators were excluded from access to aphid prey (89.38%). In the no exclusion
treatment, where both types of predators (aerial and ground dwelling) had equal access to
aphid prey, the decrease in aphid numbers was the maximum (100%). All the three
coccinellid grubs and adult beetles consumed relatively more aphids at lower aphid
densities (25, 50 and 75), significantly being the maximum at a prey density of 75. At
higher aphid densities (100, 125 and 150) the consumption rates declined. The feeding
behavior of coccinellids showed a sharp decline in percentage feeding with an increase in
prey density for both adults and grubs.
Description
Diversity of Aphidophagous Natural Enemy Guild in
Maize
Keywords
null
Citation
Meena and Swaminathan, 2014