Effect of nutrition, harvesting date and fruit canopy position on yield and quality of Kinnow mandarin (Citrus nobilis x Citrus deliciosa)

Abstract

Attractive peel colour and quality development in Kinnow (Citrus nobilis Lour x Citrus deliciosa Tenara) is a prime requisite for its fair market price. The objective of study was to find out the impact of canopy position, date of harvesting and nutrition on yield and quality of Kinnow mandarin. A field experiment was conducted in a four year old Kinnow orchard using factorial randomized block design with three replications. There were nine treatments comprised of various N, P, K levels and one control; two canopy positions (external and internal) and three harvesting dates (06.12.13, 26.12.13 and 16.01.14). Statistical analysis using SAS 9.3 software and Tukey's HSD test revealed the significance of various treatments, canopy positions and harvesting dates (P<0.01).The treatment comprising 400g+600g+240g (N+P2O5+K2O/plant) was found the best among other treatments with respect to yield (20.06 kg/tree) and other quality parameters (TSS, acidity, ascorbic acid and total carotenoids). Fruits which are present on external canopy of tree were superior in terms of quality (TSS, ascorbic acid, total carotenoids) as compared to fruits present on internal canopy of the tree.The Kinnow fruits harvested during the last week of December were found superior in terms of total carotenoids in juice and peel and ascorbic acid content. While the fruits harvested in second week of January were found superior in terms of TSS and acidity. Application of 400g, 600g and 240g of NPK respectively was found beneficial for quality fruit production of Kinnow. Quality of Kinnow fruits vary as per canopy position and date of harvesting, hence they should harvest at different times and also from different canopy positions according to purpose.

Unveiling biomarkers for postharvest resilience: the role of canopy position on quality and abscisic acid dynamics of ‘Nadorcott’ clementine mandarins

“…Regarding canopy position, this study showed that outside (sun-exposed) fruit had higher TSS but lower juice content and colour lightness than inside (shadowed) fruit. This is in agreement with the results reported by Thakre et al (2015) and Olarewaju et al (2018), who found that fruit from the external canopy had higher TSS and total carotenoids than fruit from the internal canopy. From all the positions studied, fruit on the lower inside canopy showed the highest juice content and ascorbic acid, and the lowest TSS, TA, and fructose and glucose content, while the upper outside fruit had the opposite results.…”

“…However, the results showed that the rind of fruit harvested in March was redder and there was less variability in colour hue within canopy positions. This confirms previous studies where 'Kinnow' mandarins harvested in India during the last week of December had higher ascorbic acid and total carotenoid content in the peel and juice than fruit harvested two weeks later (Thakre et al, 2015). Similarly, early maturing cultivars of satsumas ('Iwasaki', 'Okitsu', and 'Goku Wase') had higher absorption of carotenoids in the juice vesicles and advanced colour changes in the flavedo than latematuring (Sun et al, 2021).…”

“…The quality profile of citrus fruit is highly dependent on the horticultural maturity at harvest (Lado et al, 2018;Liu et al, 2021;Sun et al, 2021), and factors like fruit canopy position have been shown to affect the postharvest quality of citrus. Previous research has demonstrated the effect of these factors on the pre-and postharvest quality of different citrus cultivars like 'Kinnow' mandarins (Thakre et al, 2015), 'Nules' clementines (Cronje et al, 2011a(Cronje et al, , 2011bMagwaza et al, 2013;Ncama et al, 2018a, b), and 'Iwasaki', 'Okitsu', 'Goku Wase' satsumas (Sun et al, 2021) as well as 'Navel' and 'Valencia' oranges (Zacarıás-Garcıá et al, 2022). However, to the best of our knowledge, this is the first time that the effect of fruit canopy position on consumer acceptance of 'Nadorcott' clementines has been studied.…”

“…However, the horticultural maturity at which citrus is harvested can vary, depending on intended use and targeted markets. Hence, fruit harvested at different times during the season will exhibit varying quality categories (Thakre et al, 2015;Rokaya et al, 2016;Sun et al, 2021).…”