Guava Improvement in India and Future Needs

Guava (Psidium guajava L; Myrtaceae) is an important fruit crop of India. High heterozygosity and frequent cross pollination resulted in the present day variability in seedling populations from which promising genotypes have been selected. As of now, there are about 160 cultivars available in India, among which 'Allahabad Safeda' and 'Sardar' varieties are widely cultivated. Crop improvement work attempted in India resulted in release of several superior selections / hybrids. Also, interspecific hybrids resistant to guava wilt were developed at CISH, Lucknow which are graft compatible with commercial varieties of P. guajava. The use of new biotechnological tools like DNA fingerprinting to study the extent of genetic variation among cultivars, rapid multiplication through in vitro shoot-tip culture needs to be employed extensively. Attempts need to be made to spot genetic markers for wilt resistance to improve efficiency in developing wilt resistant clones and ischolar_mainstocks. Survey to identify superior genotypes with Allahabad Safeda traits and high density planting characters like early bearing, compact plant type, favourable response to pruning, good branch angle to minimize branch breakage even under heavy bearing, and, with a high fruit : shoot ratio need to be paid due attention. Work on aneuploidy breeding, development of autotetraploids and in vitro genetic manipulation of somatic cells needs to be intensified.