Prospects of classical cross protection technique against Citrus tristeza closterovirus in Pakistan: A review

In Pakistan citrus groves in general are facing a serious problem of decline that is attributed to different causes. The major cause, however, is the prevalence of citrus virus and virus-like diseases; Citrus tristeza virus (CTV) is of utmost concern. Although CTV has been identified and characterized on the basis of serological and physical proper - ties, no information is available on the strains of CTV in Pakistan. The identification of CTV strains will be helpful in developing strategies to control the decline of citrus trees to a great extent. Many citrus growing countries have success- fully used the technique of cross protection to minimize the drastic effect of severe CTV strains. By pre-immunization of the citrus tree with mild strains, the decline can be controlled to increase the life span of the citrus tree. In this study we focus on the possibility of establishing a cross protection technique in Pakistan against the CTV strains.