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Oxidative damage leading to loss of nutritional quality and pericarp discoloration of harvested litchi fruits drastically limits consumer acceptance and marketability. In the present investigation, the impact of postharvest melatonin application at different concentrations, i.e., 0.1 mM, 0.25 mM, and 0.5 mM, on fruit quality and shelf life of litchi fruits under cold storage conditions was studied. The results revealed the positive effect of melatonin application at all concentrations on fruit quality and shelf life. However, treatment with 0.5 mM concentration of melatonin resulted in minimum weight loss, decay loss, pericarp discoloration, and also retained higher levels of TSS, acidity, total sugar, ascorbic acid, anthocyanin, antioxidant, and phenolics content during cold storage. Melatonin administration also restricted the enzymatic activity of the polyphenol oxidase (PPO) and peroxidase (POD) enzymes in the fruit pericarp and maintained freshness of the fruits up to 30 days in cold storage. At the molecular level, a similar reduction in the expression of browning-associated genes, LcPPO, LcPOD, and Laccase, was detected in preserved litchi fruits treated with melatonin. Anthocyanin biosynthetic genes, LcUFGT and LcDFR, on the other hand showed enhanced expression in melatonin treated fruits compared to untreated fruits. Melatonin, owing to its antioxidant properties, when applied to harvested litchi fruits retained taste, nutritional quality and red color pericarp up till 30 days in cold storage. [ABSTRACT FROM AUTHOR]

The pericarp browning and postharvest microbiological decay of litchi fruit (Litchi chinensis Sonn cv Kwai Mai) significantly reduce its commercial potential in the fresh market. In this study, different combinations of modified atmosphere packaging (MAP) were applied at 5 ± 1 °C based on the use of natural gases that are innocuous to human health and an alternative to commercially adopted sulfur dioxide (SO2) treatment. The results showed that control fruits, after 6 days of storage, begin to show the first symptoms of decay, revealed by the appearance of lesions and microbial infections determined by total mesophilic microorganisms and molds. This is not the case in the MAP-treated fruits and the MAP 3-treated (5% O2 + 20% CO2 + 75% N2) fruits that show the best results. The control fruits, moreover, turned completely brown by the end of the storage period. The MAP 3 treatment was the most effective in preventing browning and the loss of the red pericarp color and vitamin content and in maintaining acceptable SSC/TA levels and flavor. In addition, a microbiological analysis revealed that all the MAP-treated litchi fruits did not harbor undesirable microorganisms during the entire cold storage period. In conclusion, the MAP 3 conditions delayed pericarp browning and maintained the better organoleptic quality of litchi fruits. [ABSTRACT FROM AUTHOR]

‘Yu Her Pau’ litchi (Litchi chinensis) has excellent fruit quality. However, its production on Taiwan is limited by low productivity despite being regarded as a high-quality fruit. It is known that litchi’s leaves play a critical role in floral induction under low temperature. Thus, we hypothesized that the flower intensity in spring could be manipulated by altering the leaf quality in winter, thereby increasing crop load. In this pilot study, ‘Yu Her Pau’ trees were pruned in mid-December [early pruning (EP)], one of the common cultural practices carried out by growers in the region, as control or mid-January [late pruning (LP)]. This resulted in 50% and 100% canopy foliage for EP and LP trees, respectively, between mid-December and mid-January. At the peak blooming time in March, LP trees produced significantly more female flowers than EP trees (95.8 and 56.1/panicle, respectively) with no negative effects on initial fruit set number, fruitlet abscission, or fruit quality at harvest. Our results suggest additional mature leaves present on trees in mid-December onward may benefit litchi flower formation without affecting fruit retention. Thus, preserving leaves with delayed pruning might potentially mitigate the negative impacts of warmer winters due to climate change on litchi flowering. [ABSTRACT FROM AUTHOR]

The pericarp browning and postharvest microbiological decay of litchi fruit (Litchi chinensis Sonn cv Kwai Mai) significantly reduce its commercial potential in the fresh market. In this study, different combinations of modified atmosphere packaging (MAP) were applied at 5 ± 1 °C based on the use of natural gases that are innocuous to human health and an alternative to commercially adopted sulfur dioxide (SO2) treatment. The results showed that control fruits, after 6 days of storage, begin to show the first symptoms of decay, revealed by the appearance of lesions and microbial infections determined by total mesophilic microorganisms and molds. This is not the case in the MAP-treated fruits and the MAP 3-treated (5% O2 + 20% CO2 + 75% N2) fruits that show the best results. The control fruits, moreover, turned completely brown by the end of the storage period. The MAP 3 treatment was the most effective in preventing browning and the loss of the red pericarp color and vitamin content and in maintaining acceptable SSC/TA levels and flavor. In addition, a microbiological analysis revealed that all the MAP-treated litchi fruits did not harbor undesirable microorganisms during the entire cold storage period. In conclusion, the MAP 3 conditions delayed pericarp browning and maintained the better organoleptic quality of litchi fruits.

The residual sulfite caused by sulfur fumigation (SF) is a hazard to health and influenced the export trade of litchi. Desulfurization (DS) is a valid chemical method to reduce the residual sulfite. However, the effect of DS on fumigated litchi has not been studied at physiological and molecular level. This study was aimed to evaluate the effect of DS (SF plus 3% desulfurizer) on the postharvest quality, sulfite residue, and the sulfite metabolism in sulfitated "Feizixiao" litchi during the 4°C storage. Results indicated that the DS promoted the color recovery of sulfitated litchi and achieved an effect similar to SF on controlling rot and browning. DS recovered the water content and respiration rate of sulfitated litchi pericarp. Thus, DS improves commodity properties of sulfitated litchi. Moreover, DS greatly reduced sulfite residue especially in pulp and ensured the edible safety of sulfitated litchi. The activities of sulfite oxidase, sulfite reductase, serine acetyltransferase, and O‐acetylserine(thiol) lyase in pulp increased after SF but fell down after DS while the expressions of their encoding genes decreased after SF but then rallied after DS. These results indicated the key role of these enzymes in sulfite metabolism after SF and DS changed the sulfite metabolism at both enzymatic and transcriptional level. It could be concluded that DS used in this study was an effective method for improving the color recovery and ensuring the edible safety of sulfitated litchi by not only chemical reaction but also both of enzymatic and transcriptional regulation. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine whether the total number and percentage of female flowers and fruit yield were influenced by the type of inflorescence, i.e., leafless or leafy inflorescences in 'Yu Her Pau' litchi (Litchi chinensis Sonn.). Four 10- year-old field-grown plants in Chunghua, Taiwan, were assessed between March and June 2013. In total, 24 inflorescences comprising 12 each of leafless and leafy in- florescences were investigated. Leaves of the leafy inflorescence, defined as the fourth successive flush, attained maturity before female flower anthesis on 16 Mar. 2013. Shoot diameter and leaf number on the flowering (fruiting) shoot, total number of flowers, and total and percentage of female flowers were recorded. Fruit number, fruit set rate, cluster yield, and fruit quality were also determined at harvest between the two inflorescence types. The two inflorescence types had similar shoot diameters and total leaf number on a flowering shoot. The total number of flowers, female flowers, and the percentage female flowers in leafless inflorescences were 3741, 563, and 16.2%, respectively; these values were 1.3- to 1.7-fold higher (P £ 0.05) than those in leafy inflorescences, which were 2779, 326, and 12.2%, respectively. Leafless inflorescences had significantly higher fruit numbers and fruit yield per cluster at harvest (10.2 and 321.5 g, respectively), although there was no difference (P > 0.05) in fruit set rate between the two inflorescence types. No fruit quality trait, such as fruit, pericarp, aril, seed weight, aril proportion, and total soluble solid concentration of aril, was significant (P > 0.05) between the two inflorescence types. We concluded that leafless and leafy inflorescences of 'Yu Her Pau' had similar carbon assimilation supply potential; however, leafless inflorescence had greater performance in terms of female flower number and thus fruit yield, presumably due to the absence of assimilate competition brought by synchronous development of lateral inflorescence and immature leaves of panicle. [ABSTRACT FROM AUTHOR]

• Exogenous melatonin suppressed enzymatic activities linked to oxidative browning. • Melatonin down regulated expression of LcPPO, LcPOD and laccase genes. • Melatonin minimised the weight loss, decay, pericarp browning index and maintained biochemical attributes. Litchi fruit is valued for its characteristic flavor and attractive color. However, oxidative pericarp browning soon after harvest limits its shelf-life and availability. Melatonin has been reported to mitigate several abiotic stresses in plant and plant based products. In this investigation, the effects of postharvest application of melatonin (0.1, 0.25, and 0.5 mM) on pericarp browning, shelf-life, and overall quality (weight and decay loss, TSS, ascorbic acid, total phenolic, flavonoid content, antioxidant activity, browning enzymes) of litchi fruit were determined during ambient storage. Fruits underwent to 0.5 mM melatonin treatment recorded reduced activities of PPO and POD thereby resulting in delayed oxidative browning in pericarp. This was coupled with reduced weight loss with higher retention of antioxidant compounds and potential in treated fruits during storage. The gene expression analyses revealed that postharvest melatonin application down-regulated expression of genes such as LcPOD and LcPPO and up-regulated anthocyanin related genes, such as LcUFGT and LcDFR those were linked to pericarp browning. In sum, results showed that exogenous melatonin (0.5 mM) could effectively preserve the postharvest fruit quality of litchi. [ABSTRACT FROM AUTHOR]

Phonological period and fruit quality of Jingganghongnuo (JGHN) grafted on the rootstocks of Feizixiao (FZX), Heiye (HY) and Huaizhi (HZ) respectively were recorded and comparatively studied from 2015 to 2017. The results showed that the whitish miilets and flowering stage of JGHN grafted on FZX and HY rootstocks were respectively 3 - 1 7 days and 1 - 3 days earlier than those on HZ. While the fruit maturation stage was 5 - 7 days ahead of in the same comparative situation. Compared to fruits grafted on HZ, mean fruit weight of JGHN grafted on HY and FZX were 38.18 and 35. 8 8 bigger respectively than that on HZ. In addition, more closely heart-shaped and brighter pericarp color of JGHN fruit were observed with rootstock of HZ than that with other two kinds of rootstocks. In terms of aborted-seed rates of JGHN, average value with rootstock FZX was 81.78, which was 58. 0 8 higher than that with HY, and 2.49 times of those with HZ. Vc content of JGHN grafted on HY and FZX were 30.47 and 25. 86 mg/100 g respectively, signiicantly higher than that grafted on HZ. TSS and TA of JGHN grafted on HZ were 17.88 and 0.148, both were obviously higher than that grafted on FZX and HY. [ABSTRACT FROM AUTHOR]

Litchi (Litchi chinensis Sonn.) is a commercially important fruit but its production and quality are restricted by litchi downy blight, caused by the oomycete pathogen Peronophythora litchii Chen. Volatile substances produced by a biocontrol antinomycetes Streptomyces fimicarius BWL-H1 could inhibited P. litchii growth and development both in vitro and in detached litchi leaf and fruit infection assay. Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) analyses indicated that volatile organic compounds (VOCs) from BWL-H1 resulted in severe damage to the endomembrane system and cell wall of P. litchii cells in vitro and abnormal morphology of appressoria, as well as deformed new hyphae in infection process. VOCs could suppress mycelial growth, sporulation, while with no obvious effect on sporangia germination. Based on gas chromatography-mass spectrophotometric analyses, 32 VOCs were identified from S. fimicarius BWL-H1, the most abundant of which was phenylethyl alcohol. Eight VOCs, including phenylethyl alcohol, ethyl phenylacetate, methyl anthranilate, α-copaene, caryophyllene, humulene, methyl salicylate and 4-ethylphenol, that are commercially available, were purchased and their bioactivity was tested individually. Except for humulene, the other seven tested volatile compounds shown strong inhibitory activity against mycelial growth, sporulation, sporangia germination and germ-tube growth of P. litchii. Especially, 4-ethylphenol showed the highest inhibitory effect on sporulation at a very low concentration of 2 µL/L. Overall, our results provided a better understanding of the mode of action of volatiles from BWL-H1 on P. litchii, and showed that volatiles from BWL-H1 have the potential for control of postharvest litchi downy blight. [ABSTRACT FROM AUTHOR]

This study aimed at investigating the effect of vacuum drying temperature on drying kinetics, drying rates, effective moisture diffusivity and quality parameters of litchi fruits. Peeled litchi quarters were dried at 50-70 °C at an absolute pressure of 8 kPa. Results show that the vacuum drying occurred in the falling rate period. Drying rates increased with drying temperature. The Page model provided the best fit to the drying kinetics. Effective moisture diffusivity ranged between 1.997 × 10−9 and 5.012 × 10−9 m2/s. The temperature dependence of the effective moisture diffusivity was well described by an Arrhenius-type equation. The activation energy for moisture diffusion was 41.81 kJ/mol. Drying temperature did not significantly affect product sensory acceptance, density, shrinkage and rehydration. The products dried at 50 and 70 °C presented slightly superior texture and flavor, while the product dried at 60 °C presented significantly higher lightness and lower water activity. Practical Applications This work provides valuable information on the vacuum drying of litchi fruits, which are appreciated in many countries due to their pleasant sensory characteristics. Vacuum drying is not a costly drying method. At the same time, vacuum drying produces dried foods of relatively good quality. This study could be used as a reference by small and medium scale food processors interested in producing dried litchi of good quality with relatively low investment in equipment. The understanding of the influence of drying temperature on quality parameters is useful for deciding which temperature is more appropriate depending on the desired quality aspects, while the calculation of engineering parameters is important for designing the drying process. [ABSTRACT FROM AUTHOR]

An experiment was conducted at Regional Research Station (Horticulture), Buria in district Yamunanagar of Haryana state during 2014-15 on 23-year old trees of litchi cultivar Early Large Red to improve the growth, yield and quality by foliar application of nutrients i. e. calcium, zinc and boron with different concentrations. Tree growth characters like tree height, diameter and girth were not affected by any of the treatments. Borax application at 0.80% spray resulted in highest number of fruits per branch (196.1), fruit weight (21.97 g), fruit length (3.69 cm) and fruit yield (70.33 kg/plant). Also, the quality parameters including TSS content, sugar : acid ratio, reducing and non-reducing sugar and yield of quality fruits were observed with borax at 0.80% spray treatment, while highest fruit breadth (3.15 cm) was recorded with borax at 1.0% spray. [ABSTRACT FROM AUTHOR]

The production of quality seedlings is important for the crop cycle and the main propagation type is by the air layering technique, which can be enhanced by using different substrates and plant growth regulators. Therefore, the objective of this study was to evaluate the use of a biostimulant and substrate types in the propagation of litchi tree by air layering. The experiment was installed in a commercial area in the city of Mogi Mirim, SP, Brazil and conducted in a randomized block design with a 5×2 factorial with four replications. The treatments consisted of five Stimulate® biostimulant concentrations (0, 3, 6, 9, and 12 ml L-1) and two substrate types (Plantmax® and earthworm humus). After 120 days, the root length (cm), number of roots, calloused and rooted layers percentage (%), root fresh and dry mass (g) and root volume (cm3) were evaluated. Based on the results, it was found that the concentrations of 6.1 and 6.9 ml L-1 promoted greater success in litchi tree propagation and that the layers can be produced on both evaluated substrates. [ABSTRACT FROM AUTHOR]

During May and June of 2012 and 2013, a study was conducted to assess losses at the farm, wholesale and retail levels in the supply chain of litchi in India. Changes in fruit quality parameters after harvest and the effectiveness of an improved corrugated fibre board (CFB) box versus conventional wooden box packaging to minimize postharvest losses were also studied. Farm-level samples were collected immediately after harvest from farmers' orchards in the Muzaffarpur district of Bihar state. Wholesale market samples were procured from the Delhi market, and retail samples from the Muzaffarpur and Delhi market. Real-time data on losses and quality parameters of fruits were recorded by transporting litchi from Muzaffarpur to Delhi (distance 1000 km) by truck. Studies indicated that the average loss (fruits discarded at sorting) apparent at the farm level during 2012 and 2013 was 30.4% and 25.8%, respectively. The average loss at the wholesale market level in Delhi was 15.8% and 12.4% during 2012 and 2013, respectively. The highest mean loss (up to 20.5%) was observed at the retail level. The mean fruit weight loss during transport to Delhi was 9.42% and 7.07% during 2012 and 2013, respectively. The mean total loss in the supply chain of litchi ranged from 35.3% to 43.8%. The total soluble solids, respiration and ethylene evolution in litchi fruits were found to increase after transport, whereas acidity and colour parameters ( L *, a * and b * values) significantly decreased over time. The predominant pathogen associated with fruit decay was Alternaria alternata (Fr.) Keissler. CFB packaging significantly reduced various losses, thus indicating its effectiveness in its current use in non-refrigerated trucks for transport. [ABSTRACT FROM AUTHOR]

Litchi chinensis Sonn. cv. ‘Feizixiao’ is commonly cultivated in orchards in Hainan Island of tropical China; however, its commodity value was reduced due to the non-synchronized pericarp coloration and low aril nutritional quality. 5-Aminolevulinic acid (5-ALA), a key precursor in the biosynthesis of porphyrin compounds, is known to be an effective plant growth regulator for improving fruit coloration and nutritive quality. In this study, 5-ALA solution was exogenously sprayed at concentrations of 80, 100, 120, 140, and 160 mg L −1 on the fruit peel of ‘Feizixiao’ litchi at 45 days after full bloom. Fruit growth, coloration and nutritive quality were determined. The treatment with 5-ALA at 80 mg L −1 maintained the vitamin C content of the aril at a higher level than that of the control. The application of 5-ALA significantly increased fruit length and diameter compared with that of the control, but there was no significant effect on the titratable acid content. At 20 days after 5-ALA treatment, anthocyanin contents of the pericarp were significantly higher and the hue angle (h°) was significantly lower than those of the control. Redundancy analysis showed that 5-ALA improved the skin color of ‘Feizixiao’ litchi by promoting anthocyanin accumulation, but not chlorophyll degradation, in the pericarp during the time of harvest. This study showed that 5-ALA significantly improved the skin color at harvest time and fruit quality by promoting the growth of fruit, delaying the degradation of soluble solids, increasing the edible rate, and shortening the interval of aril development and skin coloration. [ABSTRACT FROM AUTHOR]

Four different drying methods, namely, air drying (AD), microwave-assisted vacuum drying (MWVD), coupled microwave–hot air drying (MWAD), and freeze drying (FD), were studied, in terms of drying time, color, reducing sugar content, shrinkage, microstructure, and sensory evaluation. The drying rate of MWVD and MWAD were notably faster than that of AD and FD. The highest reducing sugar content was observed in MWAD, followed by MWVD. No significant differences were observed in reducing sugar between air-dried and freeze-dried products. FD had the best color and shrinkage among the other drying methods. The color and shrinkage of MWVD drying is close to the fresh litchis and much better than hot air and MWAD. Scanning electron microscopy (SEM) images showed that the MWVD and FD litchis have a porous structure, whereas AD and MWAD litchis have a compact structure. The sensory evaluation suggests that peeled litchis dried by the four studied drying methods are of a quality that is accepted by consumers. [ABSTRACT FROM PUBLISHER]

Litchi is known for its delicious taste and reddish pericarp colour. However, pericarp browning limits the postharvest life of litchi fruit with reduced fruit quality. Therefore, present study was conducted to investigate the influence of harvest location (Lahore and Haripur) as well as cultivar ('Gola' and 'Serai') on pericarp browning, changes in the biochemical quality attributes and enzymatic activities in litchi fruit. Fruit harvested from Lahore exhibited significantly higher pericarp browning index (3.99), weight loss (12.7%), ascorbic acid contents (48.9 mg 100 g-1) and activities of enzymes responsible for browning (peroxidase and polyphenol oxidase) as compared to Haripur. Moreover, fruit harvested from Lahore exhibited less SSC: TA ratio (105.3), total phenolic contents (187.35 mg GAE 100 g-1), total antioxidants (45.27%) and activity of superoxide dismutase enzyme (40.86 U mg-1 protein) than that of Haripur. On the other hand, 'Serai' fruit exhibited higher weight loss (12.86%), SSC (19.58oBrix), TA (0.24%), activities of peroxidase (35.81 U mg-1 protein) and polyphenol oxidase (25.22 U mg-1 protein) enzymes. Moreover, lower level of TPC (202.9 mg GAE 100 g-1), total antioxidants (50.2%), activities of superoxide dismutase (39.85 U mg-1 protein) and catalase (22.32 U mg-1 protein) enzymes were observed in 'Serai' than 'Gola' fruit. Results suggested that fruit harvested from Haripur exhibited better fruit quality characteristics and browning index than fruit harvested from Lahore. Cultivar 'Gola' showed better quality with less pericarp browning than 'Serai'. [ABSTRACT FROM AUTHOR]

• A combination of D. hansenii and B. atrophaeus improved quality of stored litchi. • The combined treatment enhanced defense-related enzyme activity in litchi fruit. • The combined treatment modulated plant-pathogen response. • The combined treatment up-regulated defene-related gene expression in litchi fruit. Postharvest disease and peel browning are critical problems in the storage and transportation of litchi fruit. Our previous studies demonstrated that either Debaryomyces hansenii (Y-1) or Bacillus atrophaeus (TE-7) used individually significantly reduced postharvest diseases in mango fruit. The combined postharvest use of Y-1 and TE-7 on litchi fruit (Litchi chinensis), however, has not been investigated. In the present study, the effect of the combined use of Y-1 and TE-7 on the disease index, physicochemical attributes, defense-related enzyme activity, and the transcriptomic profile of litchi fruit stored at 25 ℃ were investigated. Results demonstrated that the combined use of Y-1 and TE-7 (Y-TE) lowered the browning index (BI) and disease index (DI), inhibited weight loss (WL), reduced electrolyte leakage (EL) and the level of malondialdehyde (MDA) in stored litchi fruit. Y-TE-treated fruit maintained a significantly higher level of total soluble solids (TSS), titratable acidity (TA), and vitamin C (Vc), compared to untreated, control fruit, and also enhanced peroxidase (POD) and superoxide dismutase (SOD) activity. In addition, RNA-seq analysis of the transcriptome of treated and untreated fruit revealed that the Y-TE treatment modulated several metabolic pathways, including those involved in plant-hormone signal transduction and plant-pathogen interaction. RT-qPCR analysis indicated that the expression level of LcAUX28 , LcAUX1 , LcARF1 , LcRD19A, and LcWRKY1 were significantly up-regulated in stored litchi fruit by the Y-TE treatment. Collectively, these findings provide a greater understanding of how Y-TE prevents disease and maintains the quality of stored litchi fruit. The combined use of these biocontrol agents represents a new strategy for managing postharvest diseases and preserving the postharvest quality of litchi fruit during storage and transportation. [ABSTRACT FROM AUTHOR]

‘Calcuttia’ litchi fruits harvested at the full red color stage were pre-cooled and exposed to different treatments: hot water treatment (HWT) at 55°C for 20 seconds (T1), HWT + 1M hydrochloric acid (HCl) dip for 2 minutes (T2), sulphur dioxide (SO2) fumigation at 0.6 g/kg of fruits for 15 minutes (T3), SO2fumigation at 0.6 g/kg of fruits for 15 minutes + 1M HCl dip for 2 minutes (T4), and the control without any treatment (T5). After treatment, the fruits were removed from the bunch and packed in plastic crates, lined with low density polyethylene (LDPE) (100 gauge thickness), and stored in a walk-in cold room maintained at 2–3°C and 90–95% relative humidity (RH). The fruits were analyzed for various quality parameters, such as physiological weight loss, firmness, total soluble solids, titratable acidity, total anthocyanin content, SO2content, browning index, and sensory quality at weekly intervals for 4 weeks. The data revealed that fruits treated with SO2fumigation + 1M HCl dip for 2 minutes (T4) proved to be the most promising treatment for maintaining the red color of the pericarp, minimizing weight and firmness loss, and retaining eating quality of litchi fruits for up to 3 weeks. The control fruits, on the other hand, turned brown after 1 week of storage. [ABSTRACT FROM PUBLISHER]

Abstract: India and China account for 91% of the world''s litchi (Litchi chinensis) production. Although India is the second largest producer of litchi, its contribution to export is insignificant. Litchi being non-climacteric fruit possesses poor shelf life and fruit quality declines rapidly after harvest. Present investigation was an attempt to enhance shelf life of litchi fruit var. rose scented with integrated treatments of 1% NaCl solution, 2% wax solution and gamma radiation. Out of all, 1% NaCl coated+irradiated samples, proved out to be the best with enhanced shelf life of 24 days at 4°C (shelf life at ambient temperature without any treatment being 3–4 days). Various biochemical parameters were tested and organoleptic evaluation was done to judge the acceptability of the stored litchi samples. TSS, vitamin C, total & reducing sugar content was found in range of 14.17–15.42°Bx; 35.67–57.88mg/100gm pulp weight, 12.44–14.06% and 9.41–11.91%. Organoleptic evaluation for different parameters ranged from 5.92 to 7.72 (fair–good) at 24th day of storage. Radiation dose of 1kGy was found to be the only effective dose in which enhanced shelf life was achieved without any deterioration of various quality attributes. [Copyright &y& Elsevier]

Investigations were undertaken to develop a better understanding of assimilate partitioning behavior in litchi, with respect to the role of stored assimilates translocated from other sources in the plant during the fruiting season. The first experiment examined the fruit growth pattern in the litchi 'Shahi'. The second experiment focused on the limitation of assimilate supply to litchi fruits by leaf removal and girdling. The third experiment was aimed at fulfilling the assimilate requirement of growing litchi bunches through current photosynthesis by foliar application of a photosynthesis enhancer (triacontanol). The fruits exhibited a sigmoidal growth pattern with a phase of rapid growth 40 to 60 days after fruit set. Irrespective of method or distance of source limitation, the maximum percent of fruit drop was observed when the source limitation treatments were imposed 30 days after fruit set. Source limitation at all the distances resulted in significant increases in percent of fruit drop over those with no source limitations. With respect to different treatments, all forms of source limitation resulted in significant increase in fruit drop over the control. The results suggest that a contribution of carbohydrate from current photosynthesis for partial fulfillment of total carbon demand of growing fruits is necessary. Only no limitation of current photosynthesis contributed towards 0% loss in fruit weight while a limitation of carbohydrate translocation (girdling) contributed towards an 8.5% loss in fruit weight. However, under the condition of limited carbohydrate translocation, restriction on current photosynthesis caused a 19.1% loss in average fruit weight. Studies on foliar application of photosynthesis enhancers (triacontanol) on fruit drop in litchi under restricted (girdled) and unrestricted translocation of assimilate from other parts of the plant were conducted. These indicated a reduction in the rate of fruit drop with an increase in the concentration of triacontanol in case of unrestricted translocation of assimilate. However, under restricted assimilate translocation, increasing concentrations of triacontanol did not result in reducing the percent of fruit drop. Hence, the study clearly indicated the major role of translocated assimilates from other plant parts in fulfilling the assimilate demand of growing fruits in litchi where current photosynthesis contributes partially towards assimilate demand. [ABSTRACT FROM AUTHOR]

Abstract: The impact of picking maturity on eating quality and shelf-life of cold-stored litchi fruit was evaluated for the Thai cultivars ‘Hong Huey’ and ‘Chacapat’. Pericarp colour at harvest was specified by a litchi maturity index (LMI) and subsequent pericarp browning by a postharvest litchi colour index (PLCI), both being application-oriented indices deduced from the CIELab colour space. Fruit lots harvested within 15–20 days were distinguished as to their physiological maturity at harvest by means of principal component analysis (PCA). Irrespective of cultivars, titratable acids (TA), LMI, and fruit size contributed most to the specification of harvest maturity among seven ripeness attributes. Fruit quality was evaluated throughout cold storage (5°C, 21 or 30 days) based on 13 attributes representing aril, pericarp and fruit properties, including the contents of acids and ethanol, activities of browning enzymes, and respiration rates. Rapid loss of pericarp moisture and high enzyme activities, mainly of peroxidase, accompanied visually perceivable pericarp browning within 3–5 days irrespective of harvest maturity. Subsequently, shelf-life was chiefly limited by increasing ethanol contents. According to the overall quality differences detected by PCA, there was an impact of harvest time on fruit quality throughout. As revealed by partial least squares regression (PLS) for both key factors, quality of ‘Hong Huey’ and ‘Chacapat’ fruit was determined by picking maturity at 42% and 27% and storage time at 17% and 25%. Most important, pink to red-shelled ‘Hong Huey’ and pink-shelled ‘Chacapat’ fruit, as specified by TA, LMI and size ranges at harvest, provided optimum eating quality and were superior to green-red-shelled breaker fruit in long supply chains. [Copyright &y& Elsevier]

Litchi (Litchi chinensis Sonn.) 'Mauritius' is a popular export cultivar due to its attractive red color and excellent fruit quality. Three orchards were selected based on planting distance and routine pruning practices followed by each growing season. Orchards A and B are essentially similar regarding these production practices, whereas orchard C had overlapping canopies due to lack of routine pruning practices after each growing season and short planting distance. Canonical variate analysis was used as a statistical tool to compare fruit quality attributes from different orchards (A, B, and C) in terms of physical, chemical and sensory parameters and correlating to leaf nutrient status. The correlations and plot of loadings of the variates indicated that skin color (visual), color values (chroma and hue angle, h°), fruit weight, firmness, and consumer acceptability were the main factors that discriminated orchard C from the other two orchards. The soluble solids concentrations, titratable acidity and fruit taste were the quality attributes discriminating orchard A from orchard B. The relationship between the leaf nutrients and fruit quality attributes showed positive relationships between leaf potassium (K) and anthocyanin content and titratable acidity (TA); leaf phosphorus (P) and pericarp h°, leaf nitrogen (N) and fruit weight; leaf calcium (Ca) and fruit firmness. [ABSTRACT FROM AUTHOR]