Abstract

SUMMARY Aphis craccivora, Aphis gossypii and Longiunguis sacchari were trapped at 3 ft above ground more often over widely‐spaced than over close‐spaced groundnuts. At crop height A. craccivora and A. gossypii showed a similar but greater response to plant spacing. Numbers of Rhopalosiphum maidis and Tetraneura nigriabdominalis caught were not affected by groundnut spacing differences. All aphid species studied except T. nigriabdominalis responded to yellow, but their sensitivity to colour was less during the dry season. It is suggested that the effect of plant spacing on numbers caught was not due to colour alone, but perhaps also to the contrast of plants and soil in widely spaced groundnuts. At crop height, an alighting response was shown only by those species that feed on groundnuts. The control of rosette disease of groundnuts by early planting and close spacing appears to be due to the inhibition of the landing response in A. craccivora by the continuous ground cover resulting from these treatments.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.