Nutrient requirement and postharvest studies on bush jasmine (Jasminum sambac Ait)

Abstract

The experiment was conducted at the Department of Horticulture, College of Agriculture, Vellayani during 1998-1999 with the objective to standardise the nutrient requirement in bush jasmine and its post harvest studies. The results of experiment I revealed that the growth characters like length of main shoot, number of primary branches, length of primary and secondary branches, spread of plant in East-West and North-South direction performed well at the highest dose of major nutrients applied viz., 600 kg N, 600 kg P20S and 600 kg K20 ha'. The maximum number of secondary branches was obtained at 450 kg ha! of K20 and P20S' The yield of flowers was highest at lower doses of major nutrients applied viz., 300 kg N, 300 kg P20S and 450 kg K20 ha ". Regarding monthly yield pattern lower levels of nutrients (N and P) gave better yield in general, potassium was effective at 450 kg K20 ha". During the growth period the effect of nutrients applied was significant initially then declined in between and finally the yield increased in tune with the season. The 100 bud weight of flower buds was maximum at 300 kg ha' and 300 kg P20S ha ": The time taken for flower opening delayed at 600 kg P20S ha".

2 Foliar nitrogen was maximum at highest levels of major nutrients applied. The leaf phosphorus content was maximum at 450 and 600 kg N ha:", 600 kg ha' of P205 and K20. Content of leaf potassium was highest at 450 kg ha! of Nand P205 and 600 kg K20 ha:". Foliar magnesium was high when nitrogen was applied at 600 kg N ha:", phosphorus at 300 kg ha ". Foliar zinc content was recorded the highest when 450 kg ha! of nitrogen and potassium was applied. Phosphorus applied at 450 and 600 kg P205 ha! increased the foliar zinc content. Lowest dose of nitrogen (300 kg ha') increased the carbohydrate content of flowering shoot. Uptake of nitrogen and phosphorus was found effective at 600 kg N : 600 kg P205 : 600 kg K20 ha'": But uptake of potassium was maximum at 600 kg N : 450 kg P205 : 450 kg K20 ha". The uptake of magnesium recorded highest value at 600 kg N : 300 kg P205 : 300 kg K20 ha! and 450 kg K20 ha". Zinc uptake was maximum with highest dose of nitrogen and phosphorus applied and 300 and 450 kg K20 ha! applied. The essential oil content was maximum at nl and ra. levels. The available soil N, P, K content was maximum at the highest dose of nutrient applied (600 kg N : 600 kg P205 : 600 kg K20 hal ). The experiment II on post harvest studies on bush jasmine proved significant effects between the treatments. For the treatment V oEoSo time taken for flower opening was delayed and the time taken for retention

3 of colour and turgidity was maximum at lowest dose of Nand K (300 kg ha:") and highest dose of P applied (600 kg P20S ha'). The buds given ethylene absorbant treatment (VoE I So) along with major nutrients applied delayed the time taken for flower opening, retained colour at 450 kg ha! Nand 600 kg P20S ha". Time taken to retain turgidity was influenced by nitrogen at n2, phosphorus at P3 and potassium at k2 and k3 levels. Post harvest treatment of buds with ethylene absorbants and newspaper lining (V 1 EISa) along with major nutrients applied increased shelf life. The time taken for flower opening (n'), p-., k,,) and the colour _ .J .J of flowers was retained longer at n2 and P3 levels. In general the shelf life of flowers was extended by the vanous post harvest treatments compared to control. The time taken for flower opening was delayed maximum by ethylene absorbant treated buds. Low temperature treatment was best to increase the longevity of buds by retaining colour and turgidity,. The present study revealed that lowest dose of fertilizer application (300 kg N : 300 kg P20S : 450 kg K20 ha") favoured the floral characters, whereas highest dosage increased vegetative growth. The shelf life of flowers can be enhanced by post harvest treatmens (ethylene absorbants and low temperature) along with fertilizer application.