Introduction The whitefly Bemisia tabaci Genn. (Homoptera:Aleyrodidae) has caused millions of dollars worth of crop losses in tropical and subtropical agricultural regions in the five continents of the world (Brown, 1994). Besides the direct damage caused by B. tabaci (plant nutrient loss; physiological disorders; honey dew excretions, etc), the sweet potato or cotton whitefly is an efficient v...

At maturity, the endoparasitoid larvae of several subfamilies of the Braconidae have to emerge from inside of the host to pupate. Although the hosts hormonal milieu and the timing of larval parasitoid emergence have been studied, no report has yet focused on the physiological state of the host in connection with the emergence behavior of endoparasitoids. We investigated the mechanism of larval ...

The relationships between plant viruses, their herbivore vectors and host plants can be beneficial, neutral, or antagonistic, depending on the species involved. This variation in relationships may affect the process of biological invasion and the displacement of indigenous species by invaders when the invasive and indigenous organisms occur with niche overlap but differ in the interactions. The...

The effects of biotic and abiotic factors on stem borer parasitoid diversity, abundance, and parasitism were studied in cultivated and natural habitats in four agroecological zones in Kenya. Comparing habitat types, we found partial support for the "natural enemy" hypothesis, whereby, across all localities, parasitoid diversity was higher in more diverse host plant communities in natural habita...

Parasitism can influence many aspects of the host’s behaviour and physiology, which in turn can have a profound impact on their population and evolutionary ecology. In many host parasite interactions there is often a time lag between infection and the death of the host, yet little is known, experimentally or theoretically, about the effects that intra-class competition between parasitised and u...

Whitefly vector insects can spread the Pepper yellow leaf curl Indonesia virus (PYLCIV) that causes Begomovirus disease. One whitefly transmit virus, which belongs to genus. It is suspected more whitefly, higher incidence and severity of The increased disease affect chili yields. This study aimed assess relationship between population level, disease's intensity, production peppers. research met...

Natural parasitoid systems exhibit considerable variation in their life history properties yet little is known about the effects of development time on parasitoid fitness or of the conditions that might select for rapid development at the expense of reduced parasitoid growth. In this study the techniques of adaptive dynamics are applied to a discrete time host-parasitoid model to examine the ev...

The whitefly, Bemisia tabaci biotype B, has been shown to cause pathogenesis-related (PR) proteins to accumulate in plants as a result of direct feeding, but their specific role in plant defensive systems is unclear. Our objective was to compare accumulation of tomato PR proteins (beta-1,3-glucanase, chitinase, peroxidase, P2 and P4) in response to whitefly, with or without tomato mottle virus ...