caa a22 4500 388105518 CHVBK 20180307125336.0 cr unu---uuuuu 161130e199903 xx s 000 0 eng 10.1017/S1742758400016532 doi S1742758400016532 pii (NATIONALLICENCE)cambridge-10.1017/S1742758400016532 Pattern and rate of within-field dispersal and bionomics of the cowpea aphid, Aphis craccivora (Aphididae), on selected cowpea cultivars [Elektronische Daten] Comparative field studies were conducted during the rainy and dry seasons at the Mbita Point Field Station of ICIPE in southwestern Kenya, to investigate the pattern and rate of dispersal of Aphis craccivora on aphid-resistant (ICV-12) and aphid-susceptible (ICV-1) cowpea cultivars in relation to key weather factors. The effects of the dispersal trends on crop performance and aphid population dynamics were analysed. Treatments consisted of initial aphid releases at the north, south, west, east and centre of test plots and uninfested controls maintained on plants for 22 days. Parameters recorded included: pattern (direction of spread of aphids) and rate (number of aphid-infested plants at a given time) in test plots; crop growth and yields and associated factors such as incidence of sooty mould and plant mortality, and aphid density and associated factors, including the incidence of natural enemy species, particularly coccinellids. Dispersal was fastest when releases were made in the west, north and centre of plots, and resulted in adveVse effects on ICV-1 growth and yields. Infestations of ICV-12 did not significantly affect crop performance. There was an apparent direct, positive relationship between wind direction and pattern of spread of aphid infestations, but this pattern was more apparent during the rainy season, when wind speeds were higher, than during the dry season. The incidence of natural enemy species correlated with the spread of aphid infestations, while the abundance of coccinellids correlated with aphid density. Copyright © ICIPE 1999 Aphis craccivora nationallicence wind direction nationallicence within-field dispersal nationallicence phenology nationallicence cowpea nationallicence Vigna unguiculata nationallicence aphid natural enemies nationallicence bionomics nationallicence Kenya nationallicence Aphis craccivora nationallicence direction du vent nationallicence dispersion à l'intérieur du champ nationallicence phénologie nationallicence niébé nationallicence Vigna unguiculata nationallicence ennemis naturels du puceron nationallicence bionomies nationallicence Kenya nationallicence Annan I. Billy E.I. du Pont de Nemours & Company, Agricultural Enterprise Stine-Haskell Labs, Elkton Road, P.O. Box 30, Newark, DE 19714-0030, USA Schaefers George A. Cornell University, Department of Entomology, New York State Agricultural Experiment Station, Barton Lab, Box 462, Geneva, NY 14456-0462, USA Tingey Ward M. Cornell University, Qepartment of Entomology, Insectary Building Tower Road, Ithaca, NY 14853-2604, USA Saxena Kailash N. International Centre of Insect Physiology and Ecology, Mbita Point Field Station P.O. Box 30, Mbita, Kenya International Journal of Tropical Insect Science Cambridge University Press 19/1(1999-03), 1-16 1742-7584 19:1<1 1999 19 JTI https://doi.org/10.1017/S1742758400016532 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1017/S1742758400016532 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Annan I. Billy E.I. du Pont de Nemours & Company, Agricultural Enterprise Stine-Haskell Labs, Elkton Road, P.O. Box 30, Newark, DE 19714-0030, USA NATIONALLICENCE 700 1- Schaefers George A. Cornell University, Department of Entomology, New York State Agricultural Experiment Station, Barton Lab, Box 462, Geneva, NY 14456-0462, USA NATIONALLICENCE 700 1- Tingey Ward M. Cornell University, Qepartment of Entomology, Insectary Building Tower Road, Ithaca, NY 14853-2604, USA NATIONALLICENCE 700 1- Saxena Kailash N. International Centre of Insect Physiology and Ecology, Mbita Point Field Station P.O. Box 30, Mbita, Kenya NATIONALLICENCE 773 0- International Journal of Tropical Insect Science Cambridge University Press 19/1(1999-03), 1-16 1742-7584 19:1<1 1999 19 JTI CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge