EVALUATION OF MANUAL FRUIT HARVESTERS AND STORABILITY CHARACTERISTICS OF HARVESTED SWEET ORANGE UNDER ORDINARY ROOM STORAGE CONDITION

Abstract

Harvesting is considered as one of the crucial and critical activities in fruit production, handling and storage and market cycle. Traditional harvesting and post-harvest technique are responsible for deteriorating the fruit quality and shortening the postharvest shelf-life. Hand-picking by climbing tree, tree shaking and stick biting are most common practices for majority of the fruit orchards in Nepal that is risky, labour and time-intensive practices as well as affects market quality and nutritive value of the fruits. Therefore, there is a need for simple manual fruit harvesting tools suitable for smallholder farmers to replace the manual picking of citrus. Hence, a study was conducted to evaluate the performance of different available models of manual fruit harvester along with the evaluation of post-harvest quality (physiological loss of weight, fruit firmness, total soluble solids, acidity and rot incidence) and shelf-life assessment of those harvested fruits during storage under ordinary room condition for 26 days. Nine harvesting treatments were investigated as follows: a) Farmer practice-hand-picking (FPground), b) Farmer practice tree climbing (FPclimb), c) Hand-shaking of the tree branch (TS), d) Secateurs (SEground), e) Secateur + tree climb (SEClimb), f) Pole mounted cut and hold type picking shears (CH), g) Telescopic Long reach fruit picker (LRF), h) Fruit picker harvester with basket and cushion (PHB), i) Metal fruit picker with cotton bag (PC). The harvesting capacity of FPground, FPclimb, SEground, SEClimb, LRF, CH, PHB, PC and TS methods were 98.4±5.84, 57.52±12.43, 94.7±38.14, 49.05±5.73, 79.14±6.15, 75.08±12.44, 49.88±17.48, 52.27±11.47 and 63.12±22.27 kg/hr, respectively.. The harvesting output of CH and LRF type harvester was 29.03 (591 nos/hr) and 15.93% (531 nos/hr) higher than FPclimb practice (458 nos/hr) and that of PHB and PC method was 20.96 (362 nos/hr) and 6.11% (430 nos/hr) lower than FPclimb. Regarding storability characteristics, shelf-life was found better in SEground, SEClimb, CH, LRF than TS and FP practices.SE and CH method found effective in prolonging the average shelf-life and maintaining the quality of sweet orange compared to TS and FP. The button or calyx on the harvested fruit in SE, CH and LRF method help to control and delay the sap oozing, physiological loss of weight and lateral infection that maintain fruit firmness, prolong the shelf-life and minimize the fruit damage and rot incidence during ordinary storage. Based on our findings, hand-held secateur, cut and hold type harvester and long reach fruit picker (twist and turn) are recommended as appropriate harvesting tools for sweet orange fruit picking.