Bearing behaviour and correlation of fruit development stages with weather parameters in Kinnow mandarin under semi-arid irrigated conditions

Abstract

The present investigations were carried out with the objective to find the basic understanding of bearing behavior of Kinnow and correlation of fruit development stages with weather parameters. During four years of study, two years were observed as on years (high yield) and two years off years (low yield). There was 20-25 per cent yield reduction in off year. It was observed that during off years, flowering was delayed (19th March) with reduced flowering duration (12 days) and days to form flower (15 days) as compared to early flowering (11th and 14th March) with more flowering duration (15 and 14 days) and days to form flower (18) during on years. No much variation in flowering density was observed in on and off years. Among yield parameters June drop was higher (66.97% and 69.77%) which results in less fruit retention (16.96% and 14.78%) during off years in comparison to less June drop (53.60% and 59.50%) and more fruit retention (21.37% and 19.54%) during on years. Average fruit weight was also less in off years (153.44 and 162.18g) as compared to on years (174.12 and 178.14g). During off years’ leaf potassium content was found in deficient range. So, it may be concluded that delay in flowering, more June drop, less fruit weight and deficient leaf potassium content are responsible for low yield in Kinnow during off year. However, no significant involvement of peel content, juice content and residue content was observed. Temperature and pan evaporation were positively correlated with fruit growth parameters (diameter, fresh weight and dry weight) during early fruit growth stage (April-May) and a negetive correlation with mid (June-Sept.) and late fruit growth stages (Oct-Dec). Whereas, Temperature and pan evaporation showed significantly positive correlation with peel thickness during early and mid fruit growth stages and negative during later growth stages.