A Study on the Effect of Cloprop on Crown Size and Quality of Pineapple cv. Giant Kew

Abstract

Aims: The present study was carried out to determine the effect of 2-(3- chlorophenoxy) propionic acid (3- CPA) on crown size, yield and quality of pineapple cv. Giant Kew.
 Study Design: Completely Randomised Design
 Place and Duration of Study: Department of Horticulture, School of Agriculture Sciences and Rural Development, Nagaland University, Medziphema campus.
 Methodology: Five treatments consisted of different concentrations of the growth regulator viz., C1 (Control), C2 (50 ppm), C3 (100 ppm), C4 (150 ppm) and C5 (200 ppm) were evaluated with four replications each. Treatment was applied as foliar spray on pineapple crowns when apical flowers were in final stage of dehiscence. Growth and yield attributes viz., length and circumference of crown, crown to fruit length ratio, length of fruit with and without crown, pulp weight, peel weight, pulp to peel ratio, core weight, days taken to mature and dry matter content were recorded. Furthermore, biochemical parameters viz., TSS, titratable acidity, TSS: acid ratio, ascorbic acid, total sugar, reducing sugar and non- reducing sugar were analyzed, along with shelf life and Physiological loss in weight (PLW). 
 Results: The experiment revealed C3 (100 ppm) as optimum concentration for reduction of crown size with minimum crown length (14.28 cm), circumference (49.72 cm) and crown to fruit ratio (0.83) and showed 48% reduction in crown length over control. Also, maximum values for length of fruit (17.22 cm), pulp weight (1080 g), peel weight (403 g), core weight (200 g), shelf life (19.33 days) and minimum PLW were observed in C3 (100 ppm). It was found that higher concentration of 3- CPA reduced TSS and increased titratable acidity. Incidence of burns on lower leaves of crown was observed in 150 and 200 ppm treatments.
 Conclusion: 2-(3- chlorophenoxy) propionic acid is effective in altering the plant physiological processes and from the present experiment, treatment with 100 ppm showed effective result in terms of crown attributes, quality and shelf life.