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The lychee tree (Litchi chinensis Sonn.) still needs adequate nutritional management and fertilization recommendations in Brazil. An adequate supply of nutrients for the lychee tree is the main requirement contributing to higher-quality fruit production. This work aimed to evaluate nutrient leaf contents in the phenological stages of the "Bengal" lychee tree. The experiment was conducted with the "Bengal" cultivar in the period corresponding to the years 2019–2022 at the São Manuel Experimental Farm of the Faculty of Agricultural Sciences (FCA), Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP). The investigation collected leaf samples the plant's four phenological stages. It evaluated the contents of nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, boron, copper, iron, manganese, and zinc. The design was completely randomized, conducted in split plots (4 × 3), stage × cycle, with 10 repetitions. The plots represented phenological stages: full flowering (FF), fruit maturity (FM), 40 days after harvest (PC), and vegetative phase (VP). The subplots represented the evaluation cycles: cycle 1 (2019/2020 harvest), cycle 2 (2020/2021 harvest), and cycle 3 (2021/2022 harvest). There were climatic differences between the three evaluation cycles (years); the most significant water deficit was in 2020. There was a difference in nutrient content between production cycles and lychee tree phenological stages. The average contents in the leaves, at the different sampling times, followed the macronutrient order N > K>Mg > Ca > P>S, and Mn > Fe > B>Zn > Cu for the micronutrients. [ABSTRACT FROM AUTHOR]

Litchi has been cultivated in Italy for about two decades without showing symptoms caused by most of the phytophagous pests associated with this plant worldwide. The first record of the tiny eriophyid mite Aceria litchii in Italy and Europe is here reported, with a brief review on the knowledge on this species. [ABSTRACT FROM AUTHOR]

Accurate and reliable predictive models are necessary to estimate above and below ground biomass of plant and biomass carbon stock non-destructively. Different growth models namely viz, Linear, Allometric, Logistic, Gompertz, Richard’s, Negative exponential, Monomolecular, Mitcherlich and Weibull were fitted to the relationship between dry biomass of litchi tree components with collar diameter. Richard’s model outperformed the others and fulfilled the validation criterions to the best possible extent with lowest Akaike information criteria (AICc) of 90.47 and root mean square error (RMSE) of 1.79. The value of adjusted R2 ranged from 0.947 to 0.971 for the Richard’s models fitted on various biomass components and the ‘t’ values for all the components was found non-significant (p > 0.05) indicating the validation of the model. The estimated total dry biomass varied from 0.50 Mg ha−1 in two year to 5.71 Mg ha−1 in 10 year old litchi orchards. The estimated stored biomass carbon stock in litchi orchards (branches, bole and roots) varied from 0.10 Mg ha−1 in two year to 1.85 Mg ha−1 in 10 year orchards with CO2 sequestration potential from 0.19-4.63 Mg ha−1. [ABSTRACT FROM AUTHOR]

Lychee (Litchi chinensis) seeds, a by-product from the canned lychee processing, were hydrolyzed using various concentrations of proteases (Alcalase, Flavourzyme, and Neutrase). The protein hydrolysate produced with Neutrase at a concentration of 50 mg/mL exhibited the highest free radical scavenging activity. After ultrafiltration, the fraction containing peptides of less than 650 Da was purified by using gel filtration chromatography into G1-G3. The G1 fraction exhibited the highest activity and was further purified by reversed phase high performance liquid chromatography (RP-HPLC). Four fractions (H1-H4) were isolated and exhibited efficient nitric oxide (NO) scavenging activity. The G1 fraction inhibited NO production in lipopolysaccharide (LPS) stimulated RAW 264.7 cells with down-regulation of inducible nitric oxide synthase (iNOS) and interleukin-6 (IL-6). The results showed that lychee seed peptide hydrolysates exhibited potent anti-inflammatory activities, suggesting the peptides may be useful as additives to health products such as functional foods and/or pharmaceuticals. [ABSTRACT FROM AUTHOR]

India is one of the leading litchi (Litchi chinensisSonn.) producing countries in the world. A leaf blight on litchi was observed in April 2012 on nursery plants at Muzaffarpur, Bihar, India. Light to dark brown necrosis starting from leaf tips resulted in complete drying of leaves. Blighting of panicles and fruits were also noticed during April–June, 2014. Panicles dried out as a result of necrosis, while necrosis of pedicels led to complete drying of the rind of developing fruits. Infected tissues collected from different sites in diseased fields were cultured on potato dextrose agar (PDA), and the pathogen was identified asAlternaria alternata(Fr.) Keissler on the basis of morphological and cultural characteristics. The fungus produced greyish-black colonies on PDA with obclavate or obpyriform conidia in chains. Conidia had 1–4 transverse and 0–3 longitudinal septa, and measured 16–40 × 4–13 μm. Morphological identification was confirmed by sequencing the internal transcribed spacer (ITS) region of rDNA using ITS1 and ITS4 primers. Pathogenicity tests indicated thatA. alternatainfected and caused blights of the leaves, panicles and fruit of litchi.Alternaria alternatahas been reported to cause post-harvest decay of litchi fruit, but this is the first report ofA. alternatacausing blights of leaves, panicles and fruit in the field. : L’Inde est une des plus grosses productrices de litchis (Litchi chinensisSonn.) au monde. En avril 2012, on a observé de la brûlure des feuilles sur les plants de litchis d’une pépinière à Muzaffarpur, Bihar, en Inde. Une nécrose brun pâle à brun foncé, apparaissant à la pointe des feuilles, provoquait le dessèchement complet de celles-ci. D’avril à juin 2014, on a également remarqué la brûlure des panicules et des fruits. À la suite de cette nécrose, les panicules se sont desséchés, tandis que la nécrose des pédicelles a engendré le dessèchement complet de la peau des fruits en cours de développement. Des tissus infectés collectés dans des champs atteints à différents sites ont été mis en culture sur de la gélose dextrosée à la pomme de terre (GDPT) et, en se basant sur les caractéristiques morphologiques et culturales, l’agent pathogène a été identifié en tant qu’Alternaria alternata(Fr.) Keissler. Sur la GDPT, le champignon produisait des colonies gris-noir avec des chaînes de conidies obclavées ou obpiriformes. Les conidies possédaient de 1 à 4 cloisons transversales et de 0 à 3 cloisons longitudinales, et mesuraient 16 à 40 × 4 à 13 μm. L’identification morphologique a été confirmée par le séquençage de la région de l’espaceur transcrit interne (ITS) de l’ADNr en utilisant les amorces ITS1 et ITS4. Les tests de pathogénicité ont indiqué qu’A. alternataavait infecté les plants de litchis et avait causé la brûlure des feuilles, des panicules et des fruits. On a déjà rapporté qu’Alternaria alternataa causé du pourrissement chez les fruits après la récolte, mais il s’agit de la première mention d’A. alternatacausant la brûlure des feuilles, des panicules et des fruits dans les champs. [ABSTRACT FROM AUTHOR]

Dietary supplements derived from plants gaining importance in recent years for development of antimicrobial agents due to their lesser side effects and easy availability. The present study consists of comparative study of essential oil components and their antimicrobial activity against human pathogenic bacteria collected from three different geographical areas of India: Baddi (Himachal Pradesh), Lucknow (Uttar Pradesh), and Bangalore (Karnataka), coded as LC-1, LC-2, and LC-3, respectively. Evaluation of chemical constituents of essential oil by gas chromatography-mass spectrometry (GC-MS) were performed. We identified seventeen compounds, representing 85.19-88.52% of the oil under study. The identified sesquiterpene hydrocarbons are in essential oil, with 63.92-70.18%, oxygenated sesquiterpens with 15.68-22.93%, fatty acid with 0.01-0.51% and aldehyde with 0.01-0.02% of the total percentage identified. The major constituents were sesquiterpene hydrocarbon (70.18%) found in essential oil collected from Lucknow, (India). Remarkable difference in content of essential oil and their antimicrobial activity were noticed collected from three different locations of India. Antibacterial activity of the tested oil revealed the highest antibacterial porential was produced by Litchi chinensis oil collected from Lucknow (30±0.01) on S. pyrogens. [ABSTRACT FROM AUTHOR]

A novel starch was isolated from litchi kernel and compared with mango kernel starch. The properties studies were physicochemical, morphological, pasting, rheological, X-ray diffraction, and morphological. Litchi kernel starch had significantly (p< 0.05) higher amylose content and solubility, whereas its swelling power and paste clarity were lower than mango kernel starch. Peak viscosity and breakdown viscosity of litchi kernel starch were lower than mango kernel starch; however, it showed higher setback viscosity. The scanning electron microscopy revealed the presence of starch granules varying in size and shape from small to large and oval to elliptical, respectively, in litchi kernel starch. The mean length of small and large litchi starch granules was 9.52 and 50 µm, respectively, while the mean breadth of small and large litchi starch granules was 7.14 and 35.7 µm, respectively. X-ray diffractions of both litchi and mango kernel starches showed typical A-type patterns. During heating, litchi kernel starch showed higher peak G’ (storage modulus), G’’ (loss modulus), and breakdown in G’ in comparison to mango kernel starch. The peak tan δ of litchi and mango kernel starch was <1, which indicated that both litchi and mango kernel starches were more elastic than viscous. [ABSTRACT FROM AUTHOR]

A new and very occasional pest of lychee trees (Litchi chinensis) was recently identified from New Caledonia—the endemic weevil Acanthopygus griseus Montrouzier, 1861 (Coleoptera: Anthribidae). This is the first report of an anthribid weevil causing significant damage to living trees. [ABSTRACT FROM PUBLISHER]

Context: The study was carried out to evaluate the effect of the aqueous fruit pericarp extract ofLitchi chinensis(APLC) on parameters which leads to diabetic cataractogenesis and retinopathy in the streptozotocin-induced diabetic rats. Objective:The objective of the study is to evaluate the APLC forin vivoantioxidant activity and its role in inhibiting the polyol pathway and formation of advanced glycation end products (AGEs). Materials and methods: The diabetic animals were treated withL. chinensisfor a period of 12 weeks. At the end of 12 weeks, the animals were killed and the biochemical pathways involved in the pathogenesis of cataract such as oxidative stress by protein content, superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), and polyolpathway by aldose reductase (AR) in lens homogenates, alterations in protein carbonyl content (PCO) and AGEs in both serum and lens the APLC-treated diabetic rats were compared against diabetic control rats. Cataract progression due to hyperglycemia was monitored by slit lamp bio microscope and classified into four stages. Fundoscope test and retinal histopathology were done for assessing retinopathy. Results: Statistically significant reduction in glucose, and elevation of protein content, SOD, CAT, and GSH levels and decreased levels of AR and PCO in lens homogenate and significant reduction in AGEs serum and lens homogenate were observed. Slit lamp examination, fundoscope, and histopathology showed improvement in retinal changes in APLC-treated rats compared to diabetic control animals. Conclusion: The treatment with APLC found to delay the progression of diabetic cataractogenesis and retinopathy, which might be due to its antioxidant activity, because of the presence of active phytochemicals in APLC. [ABSTRACT FROM PUBLISHER]

The available components in the flesh of litchi seem insufficient to interpret its wide and significant physiological effects. Some unusual compounds, including myo-inositol, inositol methyl derivatives and γ-aminobutyric acid (GABA) were identified as main constituents in the flesh of litchi. Their concentrations varied among cultivars but remain relatively constant during development. Litchi flesh was shown to contain moderate myo-inositol (0.28–0.78 mg g−1FW), ascorbic acid (0.08–0.39 mg g−1FW) and phenolics (0.47–1.60 mg g−1FW), but abundantl-quebrachitol (1.6–6.4 mg g−1FW) and GABA (1.7–3.5 mg g−1FW). The concentration of GABA in the flesh of litchi was about 100 times higher than in other fruits. Andl-quebrachitol is not a common component in fruits. The biological and physiological activities of inositols, inositol derivatives and GABA have been extensively documented. These compounds are probably important compositional characteristic contributing to the widely shown health benefits of litchi. [ABSTRACT FROM PUBLISHER]

Silver nanoparticles are synthesized by an eco-friendly protocol usingLitchi chinensisfruit juice as a reducing and capping agent. UV-vis spectroscopy (SPR band around 447 nm), XRD (crystallinity), HRTEM (size and morphology), EDS (elemental composition) and FTIR (surface functionalities) were used to characterize silver nanoparticles. They are highly dispersed, mostly spherical with an average size of 10 nm. The prepared nanoparticles exhibited rapid reduction of 4-nitro phenol to 4-amino phenol (K= 0.09/min) and photodegradation of methylene blue (K= 0.0335/min) under visible light. The prepared nanoparticles could be an excellent candidate for the separation of hazardous materials. [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 pericarp browning is a widespread problem caused by a wide range of factors, such as polyphenolsoxidase and peroxidase, disease, desiccation, chilling, senescence, decay, micro-cracks, and heat injury. To overcome these problems, the litchi industry commercially uses SO2, but it leaves undesirable residues. Furthermore, chemical controls of browning have been threatened by consumer preferences and regulatory issues concerning pesticide residues in fruits. Thus, there is a necessity to develop alternatives to maintain the overall quality. Several alternatives to SO2fumigation, such as hot water brushing, modified/controlled atmosphere storage, bio-control agents, surface coating, cold storage, and irradiation, have been proposed. [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]

The present research was carried out to investigate the allelopathic activity ofLitchi chinensisSonn., an important exotic fruit plant of subtropical to tropical areas. The aqueous methanol extract ofL. chinensisleaves at four different concentrations was examined against the germination of lettuce (Lactuca sativaL.) and barnyard grass (Echinochloa crus-galliL. Beauv.), and the seedling growth of cress (Lepidum sativumL.), lettuce, alfalfa (Medicago sativaL.), timothy (Phleum pratenseL.), Italian ryegrass (Lolium multiflorumLam.) and barnyard grass. The hypocotyl/coleoptile and root growth of all test plants were significantly inhibited by the extracts at concentrations ≥0.01 g dry weight equivalent (dry wt. eq.) extract mL−1. The inhibitory activities of the extracts were proportional to the extract concentrations. At concentration 0.1 g dry wt. eq. extract mL−1, the extracts completely inhibited the hypocotyls of cress, lettuce and alfalfa, and the root growth of all test plant species. At the same concentration, a complete inhibition of lettuce seed germination and a significant delay of germination on barnyard grass were also observed. TheI50values for the hypocotyl/coleoptile and root growth of test plants range from 0.002 to 0.079 g dry wt. eq. extract mL−1. These results suggest thatL. chinensisleaf extracts possess allelopathic properties and contain allelopathic substances. Therefore, the plant could be used as a candidate for isolation and identification of those active substances, which may explore the interactions ofL. chinensiswith other neighbouring plants under natural settings. Further, the leaf extracts and/or their residue could be directly used as bioherbicides, or the active substances isolated from this plant may possibly be used as herbicide or templates for new natural, biodegradable herbicide for alternatives of cruel synthetic herbicides in most sustainable manner. To the best of our knowledge this is the first report about the allelopathic activity ofL. chinensis. [ABSTRACT FROM PUBLISHER]

Context: Litchi chinensis Sonn. (Spindaceae) is an important economic fruit of Thailand. Therapeutic effects of the fruits are contributed by anti-inflammatory phenolics. Objective: To extract the litchi fruit pericarp in order to identify biologically actives substances with potential for cosmetic application. Materials and methods: The litchi pericarp was macerated by 70% ethanol (EtOH) and partitioned using n-hexane and ethyl acetate (EtOAc). In vitro antioxidant activities were assessed by 1, 1-diphenyl-2-picrylhydrazyl (DPPH), ABTS and ferric reducing ability of plasma (FRAP) assays including tyrosinase inhibitory effect. Cellular radical scavenging capacity was monitored in a normal human fibroblast cell culture (NHF). Total phenolic content was determined and characterized by HPLC. Results: The EtOAc fraction was a significant antioxidant, stronger than ascorbic acid ( p < 0.01), as assessed by ABTS (IC50 = 7.137 ± 0.021 μg/mL), DPPH (IC50 = 2.288 ± 0.063 μg/mL) and FRAP (EC1mMFeSO4 = 8013.183 ± 58.804 μg/mL) assays. It demonstrated an antityrosinase effect (IC50 = 197.860 ± 1.230 μg/mL) and showed no cytotoxic activity toward Vero and NHF cells, at a maximum tested concentration (50 μg/mL), with cellular antioxidant activity. Total phenolic content was highest in the most potent antioxidant fraction. Quercetin, rosmarinic and gallic acids were found. Total phenolic content is highly related to FRAP, antityrosinase, and ABTS activities. Discussion and conclusion: Pericarp from litchi fruit can be obtained abundantly from agricultural waste, and the strong antioxidant activity demonstrated in this report may have application in topical cosmetic products. This ecological antioxidant can be prepared using a feasible method resulting in less waste and increased agro-industrial profitability. [ABSTRACT FROM AUTHOR]

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]

The equilibrium moisture contents of litchi (Litchi Chinensis Sonn.) were experimentally determined using the dynamic method at temperatures of 30, 40, and 50°C over a range of relative humidity values of 12 to 95%. Five models were tested to fit the experimental isotherm data of litchi. The GAB model fitted the best to experimental isotherm data. The agreement between experimental and predicted values of this model is excellent (RMSE 1.8 to 3.4%). The isosteric heats of sorption water were also determined from the equilibrium data using the Clausius-Clapeyron equation and it was found to be a function of equilibrium moisture content. [ABSTRACT FROM AUTHOR]

The molecular structures of the binding between human immunodeficiency virus-1 protease (HIV-1PR) and various inhibitors including existing extensive natural products extracts have been investigated for anti-HIV drug development. In this study, the binding of HIV-1PR and a terpenoid from Litchi chinensis extracts (3-oxotrirucalla-7,24-dien-21-oic acid) was investigated in order to clarify the inhibition effectiveness of this compound. Molecular dynamics (MD) simulations of HIV-1PR complex with 3-oxotrirucalla-7,24-dien-21-oic acid were performed including water molecules. The MD simulation results indicated the formation of hydrogen bonds between the oxygen atoms of the inhibitor and the catalytic aspartates, which are commonly found in inhibitors-protease complexes. On the other hand, no hydrogen bonding of this particular inhibitor to the flap region was found. In addition, the radial distribution function of water oxygens around the catalytic carboxylate nitrogens of Asp29 and Asp30 suggests that at least one or two water molecules are in the active site region whereas direct interaction of the inhibitor was found for catalytic carboxylate oxygen of Asp25. The results of this simulation, in comparison with the structures of other HIV-PR inhibitor complexes, could lead to a better understanding of the activity of 3-oxotrirucalla-7,24-dien-21-oic acid. [ABSTRACT FROM AUTHOR]

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]

Changes in structural calcium and galacturonan concentrations, the degree of methylesterification of pectins, the activities of pectin methylesterase (PME) and soluble and wall-bound peroxidases (POD), and amino acid compositions of structural proteins in the fruit pericarp (skin) were studied in cracking-resistant 'Huaizhi' and cracking-susceptible 'Nuomici' litchi. Structural calcium concentrations were higher in 'Huaizhi' than in 'Nuomici' and decreased from 22 d to 52 d after anthesis (DAA), then increased. Galacturonan concentrations increased over time and were higher in 'Huaizhi'. Methylesterification of pectins increased from 50% at 22 DAA, to 55% at 78 DAA in 'Huaizhi', but fluctuated around 48% in 'Nuomici'. PME activity was significantly higher in 'Nuomici' than in 'Huaizhi' in the later stages of fruit development (>50 DAA). The activities of soluble (SPOD) and ionically wall-bound POD (IWBPOD) increased with fruit development. Maximum SPOD activity was similar in both cultivars, whereas the peak activity of IWBPOD was higher in 'Nuomici' than in 'Huaizhi'. Total concentrations of SDS-soluble amino acids were similar in the two cultivars. Total structural proteins (SDS-insoluble amino acids) decreased with fruit development. Among the SDS-insoluble amino acids, hydroxyproline was the only one that increased over time. The results suggest that higher levels of structural calcium and galacturonans may contribute to cracking resistance in 'Huaizhi', while a higher activity of IWBPOD, which catalyses the formation of phenolic cross-linkages and an irreversible increase in the rigidity of cell walls, may be associated with cracking susceptibility in 'Nuomici'. Structural proteins may not be involved in resistance to cracking in litchi cultivars. [ABSTRACT FROM AUTHOR]

The effects of the synthetic cytokinin N-(2-chloro-4-pyridyl);N′-phenylurea (CPPU) on fruit development and the storage-life of litchi (Litchi chinensis Sonn.) cv. ‘Mauritius’ were examined in Israel over 5 years, CPPU at 5 – 10 mg l-1, applied to green or slightly red fruitlets (25 or 30 mm in diameter), delayed harvesting by 2–3 weeks compared with control trees. At harvest, CPPU-treated fruit that attained a red colour comparable to that of earlier harvested control fruit, were 20–25% larger with total soluable solid contents:titratable acidity (SSC:TA) ratios more than 50% higher than the controls. Despite their high SSC:TA ratios, CPPU-fruit stored well for 6 weeks at 1°C due to reduced browning, lower decay development and less aril discolouration, and maintained an acceptable flavour. These results suggest that CPPU can be used to extend the harvest season for litchi fruit. [ABSTRACT FROM AUTHOR]

Quantitative and qualitative changes in sugars and organic acids were investigated in two litchi (Litchi chinensis Sonn.) cultivars, ‘Feizixiao’ and ‘Nuomici’, during aril development, and their levels measured in another six cultivars (‘Guiwei’, ‘Sanyuehong’, ‘Jizuili’, ‘Xuehuaizi’, ‘Dahongli’ and ‘Yuhebao’) at maturity. Glucose, fructose and sucrose were the predominant sugars. Litchi cultivars could be classified into three types based on their sugar composition: 1) monosaccharide-prevalent types including cvs. ‘Feizixiao’, ‘Xuehuaizi’ and ‘Yuhebao’; 2) disaccharide-prevalent types including cvs. ‘Guiwei’, ‘Jizuili’ and ‘Nuomici’; and 3) intermediate types including cvs. ‘Sanyuehong’ and ‘Dahongli’. Differences in sugar compositions between cultivars were associated with differences in the activities of certain key enzymes. Succinic acid, which was previously reported to be one of the major organic acids in litchi arils, was found to be absent in all cultivars tested in this study. The major organic acid in the litchi aril was malic acid; others included tartaric, citric and ascorbic acids. Malic acid levels increased during the early stages of aril development, followed by a dramatic decrease as the fruit approached maturity. The ratio of malic acid to tartaric acid varied from 2.6–5.7 between cultivars. The concentration of ascorbic acid decreased with fruit development until 2 weeks before harvest, when it started to increase slightly as the fruit approached full maturity. Ascorbic acid levels varied considerably among the eight cultivars tested. Monosaccharide-prevalent cultivars contained more ascorbic acid than disaccharide- prevalent cultivars. [ABSTRACT FROM AUTHOR]

Variations in the concentrations of cytokinins (CTKs) and abscisic acid (ABA) were studied in the pericarp of litchi (Litchi chinensis Sonn.) fruit using the large-fruited cv. 'Erdanli' (55.3 g per fruit) and the small-fruited cv. 'Huaizhi' (20.9 g per fruit), as well as large fruit (32.4 g) from early blooms and small (20.8 g) fruit from late blooms on the same inflorescences of cv. 'Feizixiao' from the same commercial orchard in Guangdong, China in 2000. 'Erdanli' had higher concentrations of CTKs than cv. 'Huaizhi' on three out of six sampling dates during fruit development, and Lower concentrations of abscisic acid (ABA) from 40 d after anthesis. In cv. 'Feizixiao', fruit from early blooms had higher concentration of CTKs than fruit from late blooms at all sampling dates, and lower concentrations of ABA on three out of five sampling dates. Therefore, the former had a higher CTK:ABA ratio. These data suggest that a high CTK:ABA ratio favours fruit growth in litchi. [ABSTRACT FROM AUTHOR]

Freshly-harvested litchi (Litchi chinensis Sonn., L) fruit, of the cultivar `Mauritius', were subjected to 5 mm post-harvest dip treatments in aqueous solutions of: potassium metabisulphite, or Vapogard®, or Chitosan or combined treatments of: potassium metabisulphite + Vapogard®, or Chitosan + potassium metabisulphite, or Anolyte® + Triton X-100 + Chitosan, or ammonia + Carnauba wax. Standard commercial sulphur dioxide fumigation was included as a comparative control. After treatment, fruit were held at 1°C, 95% RH for 21 d to simulate refrigerated sea shipment conditions, then held at 18°C, 80% RH for 2 d. Several parameters were used to evaluate fruit quality. Combined post- harvest dip treatment with potassium metabisulphite + Vapogard® retained fruit marketability most effectively, preventing severe browning post-harvest diseases, and retaining fruit firmness. Potassium metabisulphite + Vapogard® dip treatment also revealed superior eating quality, with a 19.5% soluble solids concentration, 0.2% titratable acidity and a decline in anthocyanin concentration. Fruit fumigated with sulphur dioxide showed increased weight loss with intensified micro-cracks on the pericarp. Chitosan was most effective in reducing the total microbial fructoplane population compared to other treatments. Penicillium expansum Link. and Cladosporium spp. were identified as the predominant fungi on litchi fruit used in this trial. [ABSTRACT FROM AUTHOR]

A novel complete mitochondrial genome (mitogenome) of whitefly species, collected from Litchi chinensis at Fujian province of China (hereafter whitefly_Litchi chinensis _China) (GenBank accession number: MH999477), was described in this study. The mitogenome of whitefly_Litchi chinensis _China is 15,360 bp in length and contains 13 protein-coding genes, 21 transfer RNAs, 2 ribosomal RNAs and a non-coding AT-rich region (D-loop). The arrangement of mitochondrial genes of whitefly_Litchi chinensis_China are identical with Aleurochiton aceris, but remarkably different from the mitogenomes of the other whitefly genus. Most protein-coding genes (PCGs) start with ATN, except for nad2, cox2 and atp6 genes starting with TTG, GTG, and TTG, respectively; 10 of the 13 PCGs use the typical stop codon TAN, whereas cox1, and cox2 stop with a single T. Phylogenetic analyses based on 13 PCGs support the close relationship of the sample with Aleurochiton aceris, which would provide us further insights on the taxonomy and phylogeny of Aleyrodidae. [ABSTRACT FROM AUTHOR]

This is the first record of the coconut bugPseudotheraptus wayion litchis in South Africa. Although damage on immature fruit was often in excess of 50%, chemical control ofP. wayidid not necessarily increase yields. Litchi trees flower profusely and are probably able to compensate for damage which occurs early in the production season. Because litchis have a strong tendency towards biennial bearing, it was speculated thatP. wayicould have a detrimental effect in orchards producing below-average yields. SinceP. wayidamaged approximately 50% of the immature fruit in the Nelspruit region, it is safe to assume that litchi is a good alternative host for this insect. Producers of other subtropical fruit should take cognizance of this observation and adapt control programmes for hemipterans in adjoining orchards if necessary. [ABSTRACT FROM PUBLISHER]

Diabetes is one of the major risk factors for cataract. Aldose reductase has been reported to play an important role in sugar-induced cataract. In this study, we conducted pharmacological investigations upon experimental rat lenses using extracts of the fruits of Litchi chinensis (Sapindaceae). Of the extracts and organic fractions of L. chinensis tested, a MeOH extract and an EtOAc fraction were found to be potent inhibitors of rat lens aldose reductase (RLAR) in vitro — their IC50 values being 3.6 and 0.3 μg/mL, respectively. From the active EtOAc fraction, four minor compounds with diverse structural moieties were isolated and identified as -mannitol ( 1), 2,5-dihydroxybenzoic acid ( 2), delphinidin 3- O-β-galactopyranoside-39,59-di- O-β-glucopyranoside ( 3), and delphinidin 3- O-β- galactopyranoside-39- O-β-glucopyranoside ( 4). Among these, 4 was found to be the most potent RLAR inhibitor (IC50 = 0.23 μg/mL), and may be useful in the prevention and/or treatment of diabetic complications. [ABSTRACT FROM AUTHOR]