Harnessing stress-tolerant wild bananas for crop improvement

Abstract

Climate change impacts crop production through the imposition of different abiotic and biotic stresses, and by altering the prevalence of pests and diseases. The wild relatives of crop plants exhibit enhanced tolerance to environmental stresses due to reduced severity of selection of agriculturally important traits. Wild bananas represent a largely untapped wealth of genetic diversity. Although some wild relatives of the banana crop have been screened for their tolerance to different biotic and abiotic stresses, many remain to be explored. The wild bananas show more hardiness and higher resilience to different stressors in comparison to their cultivated counterparts. They have been harnessed in banana improvement programmes to enhance stress tolerance and productivity. To utilise wild bananas for crop improvement, they need to be readily available to breeders. This warrants devising conservation strategies and the development and maintenance of centres from which different accessions can be procured. In this article, we have discussed some important biotic and abiotic stresses including banana wilt disease, Black Sigatoka disease, viral diseases, salt stress and drought stress where wild bananas are used for imparting tolerance. The conservation of wild bananas, related challenges and contemporary limitations related to their use for crop improvement has also been outlined. Bananas being most important food crop in the world and generally understudied, here, we present a comprehensive review of the use of wild relatives of banana and their related germplasm for the improvement of biotic and abiotic stress tolerance.