Fitness of Mango for Colonization in Low Fertility Soils and Dry Lands: Examination of Leaf Life-Span, Leaf Nutrient Resorption, and Nutrient Use Efficiency in Elite Mango Varieties

摘要

Mangoes are native to India. They are grown extensively in all agro-ecological regions of South and Southeast Asia. At present, several varieties of mango are under cultivation whose suitability to different agro-ecological regions differs with theirorigin. The present study aimed to investigate the suitability of mangoes for colonization in low fertility soils and dry-land areas by examining various plant traits, like leaf life-span (LLS), leaf chlorophyll, leaf mass, leaf nutrient resorption efficiency, nutrient proficiency, and nutrient use efficiency (NUE) in elite mango varieties originated from diverse environment, like humid coastal regions under nutrient-poor environment through semiarid tropics under moderate nutrient availability environment to subtropical regions under fairly nutrient-rich environment. The mean LLS varied between 2.663 and 3.901 years. The varieties coming from low fertility environment had long LLS indicating their adaptation to low nutrient availability. Besides, longLLS permitted longer utilization of nutrients in the leaf biomass thus contributing to the improvement of NUE. On the other hand, the varieties coming from lower nutrient habitats had lower nutrient resorption efficiencies compared to those from nutrient fertile environments. However, long LLS are also associated with other leaf traits that reduce instantaneous productivity, which might reduce the growth rate of leaf biomass and shorten the functional life of the leaf. Thus it is concluded that the varieties having longer LLS are more suitable for cultivation on low fertility soils and dry lands than those with shorter LLS.