Abstract

This study was conducted throughout 2012 and 2013 seasons on leaves ofAlphonso, Balady, Bullock's Heart, Helmand, Hindy Besennara, Mabrouka, Mestekawy, Nabeeh, Ewais, Spates, Taimour and Zebdamango cultivars to evaluate their ability of mango cultivars to acquire cold injury during exposure to low temperature (storage of mango leaves at 5^?C and 10^?C). The changes in relative water content (RWC), membrane stability index (MSI),electrolytes leakage (EC%) and total free amino acids in relation to exposure to low temperature degrees were studied.TheRWC, MSI and TFAA were decreased by reducingtemperature degree from 10^?C to 5^?C. On contrast, EC%was increased. On the other hand, as the period of exposure to low temperature lengthened the values of RWC and MSI were decreased. On contrast,EC%andTFAA were increased. This was true when leaves exposed to 5°C or 10°C between the five periods of exposure (2, 4, 6, 8 or 10 days). It is clear that exposed leaves for 10 days had more effective in decreasing RWC, MSI and TFAA than other days of exposure. On the other side, the effect of low temperature exposure wassignificantlydiffered from cultivar to anotherunder the temperature of 5^°Cand 10^°C.

Keywords

mango (Mangifera indica L.), cultivars, cold tolerance, biochemical changes, subtropical plants to cold stress, plant material, physiological and biochemical studies, electrical conductivity, surface-adhered electrolytes, physical and metabolic changes, respiratory consumption, cryoprotective sugars, dehydration tissues, membrane-bond enzymes