In this paper we analyse the effects of various treatments on cotton aphids (Aphis gossypii). The standard analysis of count data on cotton aphids determines parameter values by assuming a deterministic growth model and combines these with the corresponding stochastic model to make predictions on population sizes, depending on treatment. Here, we use an integrated stochastic model to capture th...

functional response of the female ladybeetle, hippodamia variegata (goeze) (col., coccinellidae) to varying densities (5, 10, 20, 40, 60 and 80) of third instar nymphs of aphis gossypii glover was assessed in a growth chamber (25˚c, 65± ­5% rh and a photoperiod of 16l: 8d h), on the black eyed bean, vigna unguiculata (l.), in an open patch design. the logistic regression showed a type ii functi...

abstract the aphid parasitoids, aphidius colemnai viereck and a. matricariae (haliday) (hymenoptera: braconidae: aphidiinae) have high potential as the most effective biological control agents for controlling the cotton aphis aphis gossypii glover (hemiptera: aphididae). in this investigation, the effect of five constant temperatures (10, 15, 20, 25 and 30 °c) on the reproductive parameters was...

Naturally occurring parasitoids may provide sufficient control of aphid pests in fields undisturbed by insecticides. Yet the efficacy of these parasitoids may be strongly influenced by characteristics of their hosts and by the availability of alternative hosts in neighbouring crops. In the present study, parasitoid guild structure was compared in two aphid species, Brevicoryne brassicae and Lip...

China is one of the largest producers of cotton in the world. Insect pests such as cotton bollworm, cotton aphid, and mirids are the major factors that contribute to a decrease in cotton production. Transgenic cotton that expresses a gene derived from the bacterium Bacillus thuringiensis (Bt) has been deployed for combating cotton bollworm since 1997 in China, and expanded rapidly to 3.7 millio...

Phloem sap from cotton (Gossypium hirsutum L.) was collected from young and mature leaves by the aphid-stylet technique. Exudate was analyzed for carbohydrates by HPLC using sensitive pulsed amperometric detection. The predominant carbohydrate present (>90%) was identified as sucrose. A second, unidentified compound that was not one of the more commonly translocated sugars was detected in matur...

Hemipteran insects are the most devastating pest for different crops of high economic value. Colocasia esculenta tuber agglutinin (CEA), a mannose binding monocot lectin from araceae family was previously reported by the present group to be effective against some members of this class of pests. In the present study, efficacy of this potent lectin has been extended to cotton aphid (Aphis gossypi...