Abundance, population dynamics and impact of the leucaena psyllid Heteropsylla cubana Crawford in a maize-leucaena agroforestry system in Kenya
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Date
1997-06
Authors
Ogol, C.K.P.O.
Spence, J. R.
Journal Title
Journal ISSN
Volume Title
Publisher
Cambridge University Press
Abstract
We monitored abundance, population dynamics and damage impacts of the leucaena psyllid Heteropsylla cubana Crawford (Homoptera: Psyllidae) in a maize-leucaena agroforestry system. The abundance of local ladybird beetle predator populations were also evaluated. The studies were conducted between June 1993 and November 1995 at Mtwapa and Amoyo in coastal and western Kenya respectively. Alley-cropping leucaena with maize had no effect on the abundance of the leucaena psyllid or its coccinellid predators. Therefore, neither the ‘resource concentration’ hypothesis nor the ‘enemies’ hypothesis corroborated for the psyllid-leucaena system within the spatial scale of this study. Psyllid populations were generally much higher at Mtwapa than at Amoyo, suggesting possible environmental effects on population growth. Psyllid populations were influenced by weather (mainly rainfall) and availability of suitable shoots. New growth of young shoots following rainfall encouraged psyllid abundance as long as weather conditions were not extreme. Though population of the generalist ladybird beetles was correlated with that of its psyllid prey, beetles did not appear to have significant effect on prey populations
Description
DOI: http://dx.doi.org/10.1017/S1742758400016350
Keywords
Leucaena leucocephala, maize, agroforestry, leucaena psyllid, Heteropsylla cubana, population dynamics, ladybird beetles, resource concentration hypothesis, enemies hypothesis, Kenya
Citation
International Journal of Tropical Insect Science / Volume 17 / Issue 02 / June 1997, pp 183-192