Effect of pruning, paclobutrazol and chemicals on the induction of flowering on new laterals in mango (Mangifera indica L.) cv. Baneshan.
Kumar M. R., Reddy Y. N., Chandrasekhar R., Srihari D.
Author Affiliation: Department of Horticulture, College of Agriculture, Rajendranagar, Hyderabad, India.
Journal of Research ANGRAU 35 : 22-26
Abstract : A field experiment was conducted on an 8-year-old mango (cv. Baneshan) orchard in Nalgonda district, Andhra Pradesh, India, during June 2000 to July 2002. Selected shoots on mango trees were pruned back by 10 cm during the last week of June after harvesting and the cut ends were treated with 0.3% copper oxychloride paste. Urea solution at 2% was sprayed twice to all shoots irrespective of pruning at an interval of 6 days. Paclobutrazol, a growth retardant, was drenched to the selected mango trees at 1 g/m1 diameter of tree canopy during the first week of October. It was dissolved in 15 l of water and applied in a circular ring of 15-20 cm wide and 15 cm deep at 1.5 m distance in the soil around the drip zone of the tree. The chemicals, i.e. potassium dihydrogen orthophosphate (KH2PO4) at 1.0%, dipotassium hydrogen orthophosphate (K2HPO4) at 0.5% and orthophosphoric acid (H3PO4) at 0.5%, were sprayed twice as per the treatments at 30 days interval starting from the 2nd fortnight of October when the night temperatures started decreasing. Application of H3PO4, followed by KH2PO4, resulted in the highest percentage of new laterals flowered both in pruned and unpruned trees with and without paclobutrazol. The time taken from pruning to panicle initiation and panicle initiation to harvest was minimum in H3PO4, followed by KH2PO4, in pruned trees with paclobutrazol whereas there were no significant differences among the treatments in unpruned trees. Pruning significantly increased the number of laterals while paclobutrazol helped in early cessation of vegetative growth and in combination with phosphorus-potassium chemicals resulted in the minimum time taken for panicle initiation, ultimately leading to early maturity.