DROUGHT AVOIDANCE AS A MAIN STRATEGY OF CROP SURVIVAL IN ARID ENVIRONMENTS
Authors: I.S. Travlos
Abstract: In our days, due to the upcoming global climate change, more and more regions could be characterized as arid and semiarid. Especially in these marginal areas, several drought adapted crops and other plants might lead to the greater exploitation of land in danger of soil erosion and progressive degradation. Many of these plant species, which have a potential as agricultural crops, have either escaped attention or underestimated by modern science. Some of these plant species of arid and semi-arid environments are used to develop several strategies of drought adaptation with a particular emphasis in drought avoidance mechanisms. Tylosema esculentum (Burch.) A. Schreib, one of the most typical representatives of under-utilized plants of Africa with potential use, has some of these adaptive mechanisms which enable it to withstand or avoid water shortages. Indeed, this plant species manages drought and ensures its survival by using its tubers as water reservoirs, moving its leaflets, adapting its stomatal behaviour, etc. Consequently, it is not drought tolerant, but rather a drought avoiding species. Similarly, the careful observation of the adaptive mechanisms of many other wild or cultivated species could offer new choices in the exploitation of poor, arid regions and important alternatives toward the development of drought adaptive strategies. The subject of this study is to review the literature on some very interesting cases of drought adaptive mechanisms and to concisely present the strategy of drought avoidance.