Detection and Management Strategies of Guava Wilt Pathogen

Guava (Psidium guajava Linn.) is a popular fruit crop grown commercially around the world. In India, it is grown almost in all the states. Guava wilt is extremely severe and soil borne disease, i.e., difficult to control once the symptoms appear on the plant foliage. This disease can better be called as guava wilt complex because several pathogens viz., Fusarium oxysporum f. sp. psidii, F. solani, F. proliferatum, F. chlamydosporum, Macrophomina phaseoli, Rhizoctonia bataticola, Cephalosporium sp. Gliocladium vermoesenii, G. roseum, Verticillium albo-atrum, Acremonium sp. and Nalanthamala psidii are involved to cause guava wilt. Traditional culturing methods take a long time for identification of pathogenic isolates. A protocol has been developed for the detection of Fusarium from soil samples in the early stage of infection. The present chapter emphasize on various molecular detection techniques used to facilitate the rapid detection of pathogen from infected soil samples collected from rhizospheric zone of guava. The disease is soil-borne and is difficult to control. Numerous approaches are used to manage this disease which cause major financial loss have been proposed, including cultural, physical, biological and chemical treatment including host plant resistance. In this context, this chapter is also critically based on the different control measures of guava wilt that have been used in laboratory studies as well as in the guava fields.