Changes in physiological traits in Kinnow mandarin at various stages of fruit maturity

The changes in respiratory pattern, ethylene production, chlorophyll and carotenoids content of Kinnow mandarin at various stages of fruit maturity were studied in ten-year old plants, budded on rough lemon rootstock The respiration rate decreased significantly with advancement of fruit maturitiy. The fruits harvested at green stage had higher rate of respiration than those of mature fruits. Whereas, trend was reverse in ethylene production. The fruits harvested at mature stage produced relatively higher amount of ethylene than those harvested at green stage. However, continuous chlorophyll degradation and carotenoids synthesis appears to be exhibited by fruits with the advancement of fruit maturity. The appearance of orange colour was the result of enzymatic degradation of chlorophyll pigments. However, most of the changes in physiological traits had occurred in the fruits harvested between fully developed green and colour break stage indicating that this stage may be explored for further physiological advancement. The Kinnow mandarin fruits behaved as non-climacteric fruit because their response to respiration rate and ethylene production were different.