Refinement of management practices for jasmine (jasminum sambac L) in humid tropics

Abstract

Studies were conducted at the Department of Pomology and Floriculture, College of Horticulture Vellanikkara, to find out the effect of month of pruning and fertilisers on vegetative and floral characters of J. sambac as well as post harvest trials on extending the keeping quality of flowers. Out of different months of pruning, plants pruned in October showed maximum plant height while those pruned in July showed maximum plant spread. Number of primary and secondary branches were highest in April pruned plants which was on par with July pruned plants. There was no significant difference in the number of productive shoots. Yield was highest for January pruned plants. Hundred flower bud weight and flower bud length were also maximum for these plants. The manurial trial included organic manures, inorganic fertilizers and biofertilisers. Plant height was maximum for treatment containing Azospirillum, phosphobacteria and AMF along with NPK 120:240:240.g/plant per year in the initial months but in later months treatments containing neem cake, groundnut cake and poultry manure showed maximum plant height. Plant spread was highest in treatment containing neem cake 100g, FYM 100g and ground nut cake 100g given at monthly intervals. Productive shoots were also maximum in treatments containing neem cake, groundnut cake and poultry manure. Flower yield was also maximum in treatment containing neem cake, groundnut cake and poultry manure. This was significantly superior to all other treatments. Nutrient analysis revealed that the treatment containing chemical fertilizers had maximum amount of available nitrogen and the treatment containing organic manures had maximum amount of phosphorous in soil. Potassium content was maximum for treatment containing Azospirillum and phosphobacteria. In vegetative stage leaf nitrogen, phosphorous and potassium contents were maximum in treatment containing neem cake, ground nut cake and poultry manure. In flowering stage there was no significant difference among the treatments in the case of nitrogen. Treatment containing neem cake, ground nut cake and poultry manure showed maximum value in the case of phosphorous and potassium. Under post harvest studies packaging treatments containing polythene cover with four per cent perforation showed minimum physiological loss of weight followed by the flowers packed in polythene bag without perforation. Flower buds packed in polythene bag remained fresh up to 36 hours. In chemical treatments aluminium sulphate 25ppm delayed wilting by 42hours in both seasons. This was significantly superior to all other treatments. In chilling treatments time taken to wilt was maximum for flower buds kept at temperature of 200C followed by flower buds kept at temperature of 150C.