Tropical and Subtropical Agroecosystems (Jun 2020)
FOLIAR BIOCHEMICAL PROFILES OF NEWLY INTRODUCED YELLOW MANGO CULTIVARS IN MEXICO
Abstract
Background: mango is cultivated in most tropical and subtropical regions of the world, it is estimated that there are more than a thousand cultivars, so its regional characterization represents a priority in countries such as Mexico, which holds the first place for export. Objective: the objective of the present study was to identify biochemical characteristics (photosynthetic pigments, type and proportion of carbohydrates) of eight recently introduced cultivars and two new selections in Mexico. Methodology: by spectrophotometric analysis, the concentrations of total sugars, reducing sugars and starches were evaluated, as well as the content of chlorophylls a, b and carotenoids of the cultivars 'Nam Doc Mai', 'Rosygold', 'Mallika', 'Ivory', 'Alphonse', 'Neelum', 'Fairchild', 'Kesar', 'Ataúlfo Diamante' and 'Ataúlfo Zafiro'. Results: in the case of total and reducing sugars, the cultivars ‘Kesar’, ‘Nam Doc Mai’, ‘Ivory’, ‘Mallika’ and ‘A. Zafiro' (0.42, 0.34, 0.34, 0.33, and 0.32 mg*g-1 pf-1) presented the highest values (respectively), the starch content was very heterogeneous and 'Rosygold' (0.36 mg*g-1 pf-1) was identified as cultivar with higher levels. The results showed ‘Ivory’ (0.64, 0.59, 0.27 mg*g-1 pf-1) as the cultivar with the highest concentration of chlorophyll a, b and carotenoid photosynthetic pigments respectively. Based on the correlation analysis (r), a certain dependence could be observed between total and reducing sugars (r= 0.70), total sugars and starches (r= 0.76), reducing sugars and starches (r = 0.79). In the case of photosynthetic pigments, a close relationship between chlorophylls a, b and carotenoids was identified (r= 0.99); In the photosynthetic carbohydrate / pigment interaction, a significant correlation was observed between total sugars and chlorophylls a (r= -0.80), b (r= -0.80) and carotenoids (r= 0.82). The close relationship found between reducing sugars and chlorophyll a (r= 0.60), chlorophyll b (r= 0.99) and carotenoids (r= 0.99) stood out. Implications: it is necessary to continue the study in floral and fruiting stages to have a complete profile of the cultivars. Conclusion: these results will contribute in future agronomic studies of these varieties in the region in order to analyze their relationship with parameters such as yield and nutritional content of fruits.