Osmotic regulation in mango (Mangifera indica L.) cultivars at different phenological stages of flowering and fruiting.
Pooja Saxena, Singh V. K., Neelam Pathak
Author Affiliation: Central Institute for Subtropical Horticulture, Rehmankhera, Lucknow, Uttar Pradesh, India.
International Journal of Agricultural Science and Research (IJASR) 4 : 1-7
Abstract : Water stress in mango has been presumed to provide the stimulus for flowering, and is known as a successful signal for floral induction. Relative water content (RWC) and water potential (?w) are the most appropriate measure of plant water status in terms of the physiological consequence of cellular water deficit. The ?w and RWC were evaluated in the leaves of 'Amrapali' (regular bearer) and 'Langra' (biennial bearer) cultivars under normal soil moisture condition (50-68%) of orchard (upto 60 cm depth) in order to know their osmotic adjustment capacity at critical stage of flowering and fruit growth. In the field condition ?w and RWC in Amrapali was -6.0 MPa & 78.0%, -7.29 MPa & 74.9% and -8.7 MPa & 61.85% at pre flower bud differentiation, flower bud differentiation and panicle elongation stage respectively whereas these values were -5.11 MPa & 75.41%, -7.32 MPa & 70.20% and -7.94 MPa & 55.23% in the corresponding stages of Langra cultivar. The osmotic adjustment calculated on the basis of difference of ??morning (7:00-7:30 am) and ??hour (11:00-11:30 am) indicates that the Amrapali had higher osmotic adjustment capacity (11-31%) than Langra (10-30%) during critical stage of flowering. Relation of fruit drop and osmotic adjustment was also worked and Langra has more fruit drop (35-40%) counted at marble stage of fruit growth than the Amrapali (10-15%). These studies showed that Amrapali has more efficient mechanism for avoiding water loss than Langra cultivar.