The influence of two photoperiods (14L:10D and 24L:0D) and four wavelengths of light [white (control), blue (c. 475 ran), yellow (c. 570 nm) and red (c. 650nm)] on development and reproduction of the ladybird, Propylea dissecta (Mulsant), was investigated. The photoperiod of 14L:10D and the white-light wavelength recorded fastest development, maximum survival and reproduction. The developmental and reproductive Performance decreased in the order white > yellow > blue > red. The effect of the wavelength is probably due to the differential predatory response under different coloured arenas.

Cassava leaves damaged by green spider mite, Mononychellus tanajoa (Bondar) and undamaged leaves were analysed in the laboratory for chlorophyll content by spectrophotometry. Proximate analysis was also carried out on the leaves in the laboratory using the Association of Official Analytical Chemists methods.

More light was absorbed by the chlorophyll extract from the undamaged leaves than in the mite-damaged leaves. More light was also absorbed at the wavelength of 663 nm than at 645 nm. The concentrations of chlorophyll a and b were higher in the undamaged leaves than in the mite-damaged leaves. The concentration of chlorophyll a was higher than that of chlorophyll b both in the undamaged and mite-damaged leaves.

Mite-damaged leaves weighed less than the undamaged leaves, both when fresh and when dried. The proximate products values were less in the mite-damaged leaves than in the undamaged leaves.