Fruit blemishes caused by abiotic and biotic factors in Kinnow mandarin

M.S. Mazhar, A.U. Malik, A. Jabbar, O.H. Malik, M.N. Khan
Rind blemishes are a major concern in consumers fresh produce evaluation. External fruit quality, in terms of cosmetic look, of Kinnow mandarin (Citrus nobilis L. × Citrus deliciosa T.), the top fresh fruit of Pakistan, has been adversely affected overtime by many abiotic and biotic factors, resulting in significant annual economic losses. An experiment was conducted at three management levels, based on orchard size (small, medium and large), and three canopy positions (top, centre and bottom) to investigate the interaction between different farm management levels, fruit position on tree canopy and fruit blemishes. A separate experiment was conducted to account the nature of blemishes in ready to export fruit consignments. The blemishes were distinguished on empirical basis. Statistical analysis revealed that fruit of small orchards had maximum fruit blemishes caused by peel splitting, wind, peel miner and fruit fly. In addition, blemishes originated from fungal pathogens and greening were found predominantly high in medium size orchards. The incidence of blemishes due to nutritional imbalance and citrus canker was found more in large size orchards. With respect to the fruit position in tree canopy, fruit with maximum wind born blemishes were observed at top position of tree. In addition, fruit blemishes produced from red scale and fungal pathogens were found higher at bottom position of trees. The blemishes due to greening were found more at middle position. Assessment of fruit packed for export destinations confirmed the presence of blemishes due to peel splitting, wind, oleocellosis, red scale, peel miner, fungus, citrus canker, and greening at varying levels. These findings supported the relationship between incidence of blemishes and orchard management practices along with fruit position in tree canopy as well as their prevalence in ready-to-export consignments. Effective strategies need to be developed to minimize skin blemishes through better tree management during process of fruit development 'on tree', and implementation of strict quality control during processing to assure that the fruit quality standards are met during fruit grading and packing 'in pack-house'.
Mazhar, M.S., Malik, A.U., Jabbar, A., Malik, O.H. and Khan, M.N. (2016). Fruit blemishes caused by abiotic and biotic factors in Kinnow mandarin. Acta Hortic. 1120, 483-490
DOI: 10.17660/ActaHortic.2016.1120.74
cosmetic quality, canopy location, orchard size, processing, export

Acta Horticulturae