Effect of Wolbachia as biocontrol agent on fecundity and survival of cassava whitefly in northwest Nigeria

Abstract

Whitefly (Bemisia tabaci Genn.) is known to vectored Cassava mosaic virus (CMV) and Cassava brown streak virus (CBSV), these viruses caused major diseases of cassava in Africa. An experiment was conducted to determine the effect of Wolbachia as biocontrol agent on fecundity and survival of whitefly infesting cassava. Whiteflies infesting cassava were captured and reared using rearing cages. Wolbachia was isolated from infected cassava whiteflies, cultured and used for the inoculations. The experiment was conducted under control conditions using glass cages. Results of this research revealed that number of eggs lay by Bemisia tabaci inoculated with Wolbachia significantly (P = 0.05) reduced weeks after inoculation which significantly differ among the cassava genotypes. Number of eggs lay by B. tabaci free of Wolbachia was significantly higher (964.35) than those inoculated with Wolbachia (46.541) at 4 weeks after inoculation (4WAI). The genotype ‘Dan Aliero’ had the highest number (4WAI 82.33), while, ‘Farin rogo’ had the lowest number of eggs (4WAI 23.33). Number of whitefly nymphs and adults also significantly reduced when B. tabaci was inoculated with Wolbachia. ‘Dan Aliero’ had the highest number of whitefly nymphs and adults (4WAI = 59.00) and (4WAI = 51.00), respectively. ‘Farin rogo’ recorded the lowest number of whitefly nymphs (17.67) and adults (13.00) at 4WAI, respectively. For the first time, Wolbachia were evaluated for whiteflies management. From the finding of this study, Wolbachia can be used as biocontrol agent to suppress whiteflies infestation on cassava and other vegetable crops.