Effects of Different Climates and Soil Environments in the Yanshan Production Area on the Growth and Quality of Chestnuts

[Objectives] This study conducted investigations on the climate and soil nutrients of different chestnut orchards in the Yanshan region, selected key ecological factors affecting the growth and fruit quality of chestnuts, and provided a theoretical basis for the cultivation, introduction, and scientific planting of high-quality chestnuts. [Methods] The ‘Yanshanzaofeng’ chestnuts in four orchards located in Qianxi, Qianan, Funing, and Qinglong of Hebei Science and Technology Normal University were selected. The climate and soil nutrient conditions of the four orchards were investigated. Growth indicators such as branch length and diameter, nut weight, and internal quality indicators such as starch, fat, and protein content were analyzed. Principal component analysis was conducted on nine climate factors and twelve soil factors in the four chestnut orchards to identify the most closely related ecological factors influencing chestnut growth and quality. [Results] (i) Different orchards had varying climate conditions, with Qianan orchard having higher rainfall than the others, Funing orchard having the highest number of sunshine hours in the growing season, and Qinglong orchard experiencing the greatest temperature difference during the growing season. (ii) Significant differences were found in soil nutrient content among the orchards, with the coefficient of variation for organic matter and mineral elements ranging from 19.1% (S) to 80.3% (available phosphorus). (iii) The main ecological factor influencing chestnut growth was the photosynthetic factor, while fruit quality was influenced by a combination of climatic factors, photosynthetic factors, and nutrient factors. Key ecological factor indicators included: annual precipitation, annual sunshine hours, growing season precipitation, growing season sunshine hours, soil organic matter, available phosphorus, available potassium, alkali nitrogen, copper, zinc, available boron, and sulfur. Soluble solids were significantly positively correlated with growing season sunshine hours, and fat was significantly positively correlated with available potassium and alkali nitrogen, and significantly positively correlated with available phosphorus. [Conclusions] Orchards with high growing season precipitation, long sunshine hours, and high organic matter and nitrogen-phosphorus-potassium content in the soil are more conducive to promoting the growth of ‘Yanshanzaofeng’ chestnuts and improving fruit quality.

Prediction of Apple Fruit Quality by Soil Nutrient Content and Artificial Neural Network

The effect of soil nutrient content on fruit yield and fruit quality is very important.To explore the effect of soil nutrients on apple quality we investigated 200 fruit samples from 40 orchards in Feng County,Jiangsu Province.Soil mineral elements and fruit quality were measured.The effect of soil nutrient content on fruit quality was analyzed by artificial neural network(ANN)model.The results showed that the prediction accuracy was highest(R2=0.851,0.847,0.885,0.678 and 0.746)in mass per fruit(MPF),hardness(HB),soluble solids concentrations(SSC),titratable acid concentration(TA)and solid-acid ratio(SSC/TA),respectively.The sensitivity analysis of the prediction model showed that soil available P,K,Ca and Mg contents had the greatest impact on the quality of apple fruit.Response surface method(RSM)was performed to determine the optimum range of the available P,K,Ca,and Mg contents in orchards In Feng County,which were 10∼20 mg⋅kg^(−1),170∼200 mg⋅kg^(−1),1000∼1500 mg⋅kg^(−1),and 80∼200 mg⋅kg^(−1),respectively.The research also concluded that improving the content of available P and available Ca in orchard soil was crucial to improve apple fruit quality in Feng County,Jiangsu Province.

Effects of water and fertilizer deficit regulation with drip irrigation at different growth stages on fruit quality improvement of kiwifruit in seasonal arid areas of Southwest China

For a long time,seasonal drought occurs frequently in Southwest China,and the management of water and fertilizer in kiwifruit orchards has no quantitative standards,which seriously affects the yield and quality of kiwifruit.Therefore,the effects of water and fertilizer deficit regulation with drip irrigation(WFDRDI)on the quality of kiwifruit at different growth stages were explored to achieve water and fertilizer saving,and green and efficient production of kiwifruit.We select‘Jin Yan'kiwifruit and set two water deficit levels(W_(D20%)and W_(D40%))and three fertilizer deficit levels(F_(D15%),F_(D30%)and F_(D45%))at bud burst to leafing stage(stageⅠ),flowering to fruit set stage(stageⅡ),fruit expansion stage(stageⅢ)and fruit maturation stage(stageⅣ),respectively,with a full irrigation and fertilization as the control treatment(CK)in 2017and 2018.Results showed that the WFDRDI at stageⅡandⅢhad significant effect on fruit physical quality of kiwifruit,specifically,theⅢ-WD40%F_(D30%)andⅢ-W_(D20%)F_(D45%)treatments significantly increased fruit firmness by 13.62 and 15.59%(P<0.05),respectively;theⅡ-W_(D40%)F_(D15%)andⅢ-W_(D40%)F_(D15%)treatments significantly increased dry matter by 8.19 and 6.47%(P<0.05),respectively;theⅢ-W_(D20%)F_(D15%)treatment significantly increased single fruit weight and fruit volume by 9.33 and 12.65%(P<0.05),respectively;theⅡ-W_(D20%)F_(D15%)treatment significantly increased fruit water content by 1.99%(P<0.05).The WFDRDI had an obvious effect on fruit chemical quality of kiwifruit.TheⅢ-W_(D20%)F_(D45%),Ⅳ-W_(D40%)F_(D15%)andⅣ-W_(D20%)F_(D30%)treatments significantly increased vitamin C(Vc)content by 69.96,36.96 and 34.31%(P<0.05),respectively;theⅢ-W_(D40%)F_(D15%)andⅣ-W_(D40%)F_(D15%)treatments significantly increased total soluble solid(TSS)content by 3.79 and 17.05%(P<0.05),respectively,and significantly increased soluble sugar content by 28.61 and 34.79%(P<0.05),respectively;the contents of fructose,glucose and sucrose also had a significantly increasing trend,which was increased significantly by 5.58–19.63%,40.55–60.36%and 54.03–54.92%in theⅢ-WD40%F_(D15%)andⅣ-W_(D40%)F_(D15%)treatments(P<0.05),respectively;sugar–acid ratio was increased significantly in theⅣ-W_(D40%)F_(D15%)treatment by 64.65%(P<0.05).The degree and duration of water and fertilizer deficit had a comprehensive effect on fruit quality of kiwifruit.The WFDRDI at stageⅡandⅢcontribute to improving fruit physical quality,and the threshold of water and fertilizer deficit were 20 and 15%,respectively;stageⅢandⅣare the critical periods for improving fruit chemical quality by water and fertilizer coupling effect,and the threshold of water and fertilizer deficit were 40 and 15%,respectively.Therefore,aiming at precise water and fertilizer saving,theⅠ-W_(D20%)F_(D30%),Ⅱ-W_(D40%)F_(D15%),Ⅲ-W_(D40%)F_(D15%)andⅣ-W_(D40%)F_(D15%)treatments under WFDRDI during the whole growth period of kiwifruit were the best mode to improve quality and production of kiwifruit.

Integrated Use of Organic and Bio-fertilizers to Improve Yield and Fruit Quality of Olives Grown in Low Fertility Sandy Soil in an Arid Environment

Olive productivity should be improved through stimulating nutrition,particularly under poor fertility soils.Consequently,the objective of this study was to assess the efficacy of applying organic and bio-fertilizers on the physiological growth,yield and fruit quality of olive trees under newly reclaimed poor-fertility sandy soil in an arid environment.During a field experiment carried out at El-Qantara,North Sinai,Egypt over two consecutive seasons(2019-2020 and 2020-2021),olive Kalamata trees were evaluated under three organic fertilizer treatments alone or in combination with three bio-fertilizers treatments.Organic fertilizer was applied as goat manure(16.8 kg/tree/year),or olive pomace(8.5 kg/tree/year)in mid-December of each season vs.untreated trees.The bio-fertilizers were applied as N-fixing bacteria(150 g/tree)was inculated in early March of each season,or amino acid mixture(1.5%)was applied three times,at 70%of full bloom,21 days after full bloom,and a month later in comparison to a non-fertilized trees(control).The cultivar used was Kalamata,a dual-purpose cultivar for oil and table olives whose value increases when processed as table olives.The results indicated that the goat manure followed by olive pomace significantly enhanced photosynthetic pigments(chlorophyll a,b,and carotenoids),leaf mineral contents(N,P,K,Ca,Mg and Fe),tree canopy volume,number of flowers per inflorescence,number of inflorescences per shoot,initial fruit set,fruit retention.For fruit quality,fruit length and width,fruit weight,and total fruit yield was increased compared to the non-fertilized control.Likewise,The bio-fertilizer N-fixing bacteria followed by the amino acid mixture significantly improved all of the aforementioned parameters.Accordingly,it is recommended,both environmentally and economically to utilize organic and bio-fertizers,particularly goat manure combined with N-fixing bacteria,in low-fertility soil to sustain olive production as well as reducing mineral fertilization.

The Physiological and Molecular Responses of Exogenous Selenium to Selenium Content and Fruit Quality in Walnut

To study the effect of exogenous selenium on fruit quality in walnut(Juglans regia L.),8-year-old walnut(Qingxiang)was taken as the research object.In the fruit expansion stage,300 mg/L of sodium selenate,yeast selenium and sodium selenite solutions were applied on the leaf of walnut,and the selenium levels in leaves,pericarp and kernel were determined at the ripening stage.The fruit quality,mineral nutrient content,antioxidant enzyme activity,and related genes’expression were analyzed.The results showed that the three exogenous selenium increased the selenium levels in leaves,pericarp and kernel of walnut.They also significantly increased fruit and kernel weights,and kernel linoleic acid,but markedly decreased kernel crude fat and saturated fatty acid.Selenium spraying promoted the absorption of mineral nutrients such as potassium and zinc,but inhibited the absorption of calcium,and had no significant effect on iron and magnesium in the kernel.Three exogenous selenium increased the activities of superoxide dismutase(SOD),peroxidase(POD),ascorbate peroxidase(APX),and catalase(CAT)significantly in the kernel.Except for sodium selenate treatment significantly reduced malondialdehyde(MDA)content in the kernel,the other two selenium sources treatments had no significant effect on MDA and hydrogen peroxide(H2O2)levels.They also increased the expression of JrCu/Zn-SOD,Jr2-Cys POD,JrCyt-APX and JrCAT in kernel,to different extents.These implies that,in the walnut fruit enlargement period,the foliar spraying selenium could increase the selenium content of walnut,affect the mineral nutrient absorption,improve the antioxidant capacity and related genes’expression,and reduce the degree of peroxide,and then improve the quality of fruit.Furthermore,yeast selenium showed the comprehensive effect of the best.

Differential Expression of Genes Related to Fruit Development and Capsaicinoids Synthesis in Habanero Pepper Plants Grown in Contrasting Soil Types

Habanero pepper(Capsicum chinense Jacq.)is a crop of economic relevance in the Peninsula of Yucatan.Its fruits have a high level of capsaicinoids compared to peppers grown in other regions of the world,which gives them industrial importance.Soil is an important factor that affects pepper development,nutritional quality,and capsaicinoid content.However,the effect of soil type on fruit development and capsaicinoid metabolism has been little understood.This work aimed to compare the effect of soils with contrasting characteristics,black soil(BS)and red soil(RS),on the expression of genes related to the development of fruits,and capsaicinoid synthesis using a transcriptomic analysis of the habanero pepper fruits.Plants growing in RS had bigger fruits and higher expression of genes related to floral development,fruit abscission,and softening which suggests that RS stimulates fruit development from early stages until maturation stages.Fruits from plants growing in BS had enrichment in metabolic pathways related to growth,sugars,and photosynthesis.Besides,these fruits had higher capsaicinoid accumulation at 25 days post-anthesis,and higher expression of genes related to the branched-chain amino acids metabolism(ketol-acid reductisomerase KARI),pentose phosphate pathway and production of NADPH(glucose-6-phosphate-1-dehydrogenase G6PDH),and proteasome and vesicular traffic in cells(26S proteasome regulatory subunit T4 RPT4),which suggest that BS is better in the early stimulation of pathways related to the nutritional quality and capsaicinoid metabolism in the fruits.

Response of yield,quality,water and nitrogen use efficiency of tomato to different levels of water and nitrogen under drip irrigation in Northwestern China

The objective of this study was to investigate the effects of applying different amounts of water and nitrogen on yield, fruit quality, water use efficiency(WUE), irrigation water use efficiency(IWUE) and nitrogen use efficiency(NUE) of drip-irrigated greenhouse tomatoes in northwestern China. The plants were irrigated every seven days at various proportions of 20-cm pan evaporation(E_p). The experiment consisted of three irrigation levels(I1, 50% E_p; I2, 75% E_p; and I3, 100% E_p) and three N application levels(N1, 150 kg N ha^(–1); N2, 250 kg N ha^(–1); and N3, 350 kg N ha^(–1)). Tomato yield increased with the amount of applied irrigation water in I2 and then decreased in I3. WUE and IWUE were the highest in I1. WUE was 16.5% lower in I2 than that in I1, but yield was 26.6% higher in I2 than that in I1. Tomato yield, WUE, and IWUE were significantly higher in N2 than that in N1 and N3. NUE decreased with increasing N levels but NUE increased with increase the amount of water applied. Increasing both water and N levels increased the foliar net photosynthetic rate. I1 and I2 treatments significantly increased the contents of total soluble solids(TSS), vitamin C(VC), lycopene, soluble sugars(SS), and organic acids(OA) and the sugar:acid ratio in the fruit and decreased the nitrate content. TSS, VC, lycopene, and SS contents were the highest in N2. The harvest index(HI) was the highest in I2N2. I2N2 provided the optimal combination of tomato yield, fruit quality, and WUE. The irrigation and fertilisation regime of 75% E_p and 250 kg N ha^(–1) was the best strategy of water and N management for the production of drip-irrigated greenhouse tomato.

Advances in Genomic,Transcriptomic,and Metabolomic Analyses of Fruit Quality in Fruit Crops

Fruit quality is the main factor determining market competitiveness;it represents the combination of fruit flavor,color,size,and the contents of aromatic and bioactive substances.Research on the genetic basis of fruit quality can provide new information about fruit biology,promote genomic-assisted breeding,and provide technological support for the regulation of fruit quality via habitat selection and/or the control of environmental conditions.High-throughput sequencing is a powerful research method for studying fruit quality traits,and reference genome sequences for many important fruit crops have provided vast amounts of genomic data.To study fruit quality,it is important to select appropriate omics strategies and to analyze omics data meaningfully.Here,we summarize genomic mechanisms of fruit quality formation:gene duplication,transposable element insertion,structural variations and genome methylation in functional genes.We review the genomic,transcriptomic,and metabolomic strategies that have been used to study the genetic basis of fruit quality traits.We also describe some of the genes associated with fruit traits;these genes are a valuable resource for genomics-assisted breeding and are useful models for deciphering the mechanisms of agronomic traits,such as fruit color,size,hardness,aroma components,sugar and acid content.Finally,to maximize the application of omics information,we propose some further directions for research using omics strategies.

Peach yield and fruit quality is maintained under mild deficit irrigation in semi-arid China

We conducted a two-year study of deficit irrigation impact on peach yield and quality in semi-arid northwest China. Over two years, four-year-old peach trees were irrigated at 100, 75, 50 and 25% of peach evapotranspiration(ET_c), here, ET_c= Coefficient(Kc)×Local reference evapotranspiration(ET_o). During the April-July fruit production season we measured root zone soil water depletion, sap flow velocity, net photosynthetic rate(P_n), transpiration rate(T_r), stomatal conductance(G_s), water use efficiency(WUE=P_n/T_r), fruit quality, and yield under a mobile rain-out shelter. Increased soil water depletion reasonably mirrored decreasing irrigation rates both years, causing progressively greater water stress. Progressive water stress lowered G_s, which in turn translated into lower T_r as measured by sap flow. However, mild deficit irrigation(75% ET_c) constricted T_r more than P_n. P_n was not different between 100 and 75% ET_c treatments in both years, and it decreased only 5–8% in June with higher temperature than that in May with cooler temperature. Concurrently under 75% ET_c treatment, T_r was reduced, and WUE was up to 13% higher than that under 100% ET_c treatment. While total fruit yield was not different under the two treatments, because 75% ET_c treatment had fewer but larger fruit than 100% ET_c trees, suggesting mild water stress thinned fruit load. By contrast, sharply decreased T_r and P_n of the driest treatments(50 and 25% ET_c) increased WUE, but less carbon uptake impacted total fruit yield, resulting 13 and 33% lower yield compared to that of 100% ET_c treatment. Irrigation rates affected fruit quality, particularly between the 100 and 75% ET_c trees. Fewer but larger fruit in the mildly water stressed trees(75% ET_c) resulted in more soluble solids and vitamin C, firmer fruit, and improved sugar:acid ratio and fruit color compared to the 100% ET_c treatment. Overall, trees deficit irrigated at 75% ET_c maintained yield while improving fruit quality and using less water.

Harvest and Postharvest Factors Affecting Bruise Damage of Fresh Fruits

Fresh fruits are susceptible to bruising, a common type of mechanical damage during harvest and at all stages of postharvest handling. In quest of developing and adoption of strategies to reduce bruise damage, it is of utmost importance to understand major factors influencing bruise susceptibility of fresh produce at these stages. This review presents a critical discussion of factors affecting bruising during harvest and postharvest handling of fresh fruits. Excessive compression forces during harvesting by handpicking or machines, and a series of impacts during harvesting, transport and packhouse operations can cause severe bruise damage. The review has further revealed that bruising is dependent on a number of other factors such as produce maturity, ripening, harvest time(during the day or season) and time lapse after harvest. The susceptibility to bruising is partly dependent on how these factors alter the produce physiological and biochemical properties, and the environmental conditions such as temperature, humidity and several other postharvest treatments. Hence, the successful applications of harvesting techniques by use of trained personnel and proper harvesting equipment are essential to reduce both the incidence and severity of bruising.Furthermore, the careful selection of postharvest handling temperature and other treatments can increase resistance of fresh produce to bruise damage.

Effect of Pre-Harvest Application of Gibberellic Acid on Fruit Quality and Shelf Life of Mandarin (Citrus reticulata Blanco)

Mandarin (Citrus reticulata Blanco) is a promising fruit crop gaining popularity for its human nutrition and economic importance in Nepal. The qualitative losses during pre-harvest stage hinder the productivity and subsequently shorten the on-tree storability. An experiment was conducted to assess the effect of gibberellic acid on quality and shelf life of the mandarin fruit. GA3 at 10, 20, and 30 ppm as against of control were evaluated. Observations on fruit weight (g), fruit firmness (kg/cm2), rind colour (1 - 5 index), juice recovery (%), TSS/acid ratio, PLW (%), decay loss (%), and ascorbic acid (mg/100 ml) were recorded at three harvesting dates i.e. 20 Nov, 5 Dec, and 20 Dec and storage condition. It has been revealed that the fruits treated with GA3 at 20 ppm retained higher fruit weight (128.6 g), more firmness (3.54 kg/cm2), better juice recovery (57.75%), and greater TSS/acid ratio (21.24) at the end of study (20 December). The PLW was found less with GA3 at 30 ppm in both ambient (5.17%) and cellar (6.69%) condition as against untreated fruits (9.52% and 11.76%). Similarly, the decay loss was minimum in the fruits treated with GA3 at 30 ppm both with ambient (1.02%) and cellar condition (8.21%) as against control with ambient (5.54%) and cellar (21.58%).

Influences of open-central canopy on photosynthetic parameters and fruit quality of apples(Malus×domestica)in the Loess Plateau of China

Although open-central canopy(OCC)is popular in apple(Malus×domestica)orchards in Loess Plateau of China,its relevant photosynthetic mechanisms have not been elucidated.In this study,changes in photosynthetically active radiation(PAR),gas exchange,chlorophyll fluorescence quenching and fruit quality in apple trees were measured in OCC and compared with those in the conventional condensed round and large canopy(RLC).Results showed that light intercepted at different orientations was 44%higher by OCC than that by RLC.The improved light environment within OCC remarkably increased leaf maximum net photosynthetic rate(Pnmax)and significantly decreased stomatal limitation.Under high light,the ratio of photorespiratory rate to gross photosynthetic rate(Pr/Pg)in OCC was higher than that in RLC.Moreover,reversible component in non-photochemical quenching(r(qE))was increased,while irreversible component(r(qI))was decreased in OCC than in RLC.As a result,the fruit quality in OCC was greatly boosted as evidenced by the significantly increased single fruit weight,fruit flesh firmness and fruit soluble solid contents and the sharply decreased fruit titratable acid contents.PAR intercepted by the canopy and the fruit soluble solid contents,leaf Pnmaxor single fruit weight were positively correlated,while PAR or Pnmaxwas negatively correlated with the fruit titratable acid contents.Accordingly,the improved crown light environment and the enhanced leaf photosynthetic performance and photoprotective capacity in OCC led to the boosted fruit quality.

Response of Tomato Sugar and Acid Metabolism and Fruit Quality under Different High Temperature and Relative Humidity Conditions

The combined stress of high temperature and high relative air humidity is one of the most serious agrometeorological disasters that restricts the production capacity of protected agriculture.However,there is little information about the precise interaction between them on tomato fruit quality.The objectives of this study were to explore the effects of the combined stress of high temperature and relative humidity on the sugar and acid metabolism and fruit quality of tomato fruits,and to determine the best relative air humidity for fruit quality under high temperature environments.Four temperature treatments(32℃,35℃,38℃,41℃),three relative air humidity(50%,70%,90%)and four duration(3,6,9,12 d)orthogonal experiments were conducted,with 28℃,50%as control.The results showed that under high temperature and relative air humidity,the activity of sucrose metabolizing enzymes in young tomato fruits changed,which reduced fruits soluble sugar content;in addition,enzyme activities involved phosphopyruvate carboxylase(PEPC),mitochondria aconitase(MDH)and citrate synthetase(CS)increased which increased the content of organic acids(especially malic acid).Eventually,vitamin C,total sugar and sugar-acid ratio decreased significantly,while the titratable acid increased,resulting in a decrease in fruit flavor quality and nutritional quality in ripe fruit.Specifically,a temperature of 32℃and a relative air humidity of 70%were the best cultivation conditions for tomato reproductive growth period under high temperature.Our results indicating that fruit quality reduced under high temperature at the flowering stage,while increasing the relative air humidity to 70%could alleviate this negative effect.Our results are benefit to better understand the interaction between microclimate parameters under specific climatic conditions in the greenhouse environment and their impact on tomato flavor quality.

Application of two forms of silicon and their impact on the postharvest and the content of bioactive compounds in cucumber(Cucumis sativus L.)fruits

The metabolic activity of the fruits continues even after harvest,which results in the loss of bioactive compounds,a decrease in the quality of the fruits,softening and browning,among other negative effects.The use of certain elements such as silicon can improve postharvest quality,since it is involved in the metabolic,physiological and structural activity of plants,moreover can increase the quality of the fruits.In addition,nanotechnology has had a positive impact on crop yield,nutritional value,fruit quality and can improve antioxidant activity.For these reasons,the use of beneficial elements such as silicon in the form of nanoparticles can be a viable option to improve the characteristics of the fruits.In the present study was evaluated the application of potassium silicate(125,250 and 500 mg L^(−1))and SiO_(2) nanoparticles(125,250 and 500 mg L^(−1))during the development of the crop.The results showed that the application of silicon(potassium silicate and silicon nanoparticles)increased the content of total soluble solids(up to 15.6%higher than control),titratable acidity(up to 38.8%higher than control),vitamin C(up to 78.2%higher than control),phenols(up to 22%higher than control),flavonoids(up to 64.6%higher than control),and antioxidant activity in lipophilic compounds(up to 56.2%higher than control).This study suggests that the use of silicon can be a good option to increase the content of bioactive compounds in cucumber fruits when they are applied during the development of the crop.

Effect of Different Pollination Varieties on Qingxiang Pear Fruit Quality

With Qingxiang pear as test material,we study the effect of different pollination varieties on Qingxiang pear fruit quality. The results show that Xinshiji,Xizilu,Cuiguan and Yuanhuang as the pollination varieties for Qingxiang pear can create the best comprehensive quality,and these varieties can be chosen in production as the pollination varieties for Qingxiang pear,followed by Cuilu and Xishui.

Effects of Different Density-reducing Methods on Canopy Microenvironment, Tree Growth and Fruit Quality in Closed Apple Orchard

In order to optimize and transform closed mature apple orchards with standard rootstocks and improve the quality of fruit,taking a closed Red Fuji apple orchard as the test object,the effects of different density-reducing methods(deinterlacing,removing every other plant in each row,removing every other plant every other row)on the canopy microenvironment,tree structure,leaf photosynthesis and fruit quality were studied.The results showed that different density-reducing methods significantly reduced the orchard coverage and increased the crown transmittance.Among them,the deinterlacing treatment was the best in improving the population structure of the closed orchard,as it reduced the orchard coverage rate by 55.68 percentage points and the canopy transmittance by 82.38 percentage points,compared with the control(CK).Different density-reducing methods all could significantly reduce the branch amount in the closed orchard and optimized the branch composition.The three density-reducing methods decreased the number of branches per plant by 18.96%,12.41%and 19.58%,respectively,compared with the CK.And compared with the CK,the proportion of short branches and leafy branches to the total branches was increased by 17.13%,14.27%and 7.37%,respectively,and the proportion of long branches and developmental branches to the total branches was decreased by 24.47%,18.04%and 10.79%,respectively.The effects of the different density-reducing methods on the temperature,relative light intensity,SPAD and leaf photosynthetic rate in canopies all followed an order of deinterlacing>removing every other plant in each row>removing every other plant every other row>CK,while those on the relative humidity showed an order of deinterlacing>removing every other plant in each row>removing every other plant every other row>CK,while those on the relative humidity showed an order of deinterlacing<removing every other plant in each row<removing every other plant every other row<CK.The average single fruit weight(238.3 g),coloring index(89.2),smoothness index(83.2),soluble solid content(15.1%)and high quality fruit rate(82.4%)of the deinterlacing treatment were higher than those of other treatments,and the values were 18.2%,11.4%,5.85%,26.9%and 25.2%higher than the CK,respectively.The use of dein￣terlacing to reduce density is the best for improving the microenvironment of closed apple orchards and improving the photosynthetic efficiency and fruit quality.

Effects of Short-cut Flowering Branches on Harvest Time,Yield and Quality of Guire No.82 Mango

[Objectives]To further study the technology of short-cut flowering branches for Guire No.82 Mango,adjust its harvest time,increase yield and improve fruit quality,and increase the economic benefits of mango production.[Methods]The experiment of short-cut flowering branches was carried out for Guire No.82 Mango.[Results]At the initial flowering stage and full flowering stage of the primary inflorescence,with short-cut flowering branches and corresponding cultivation techniques,Guire No.82 Mango was easy to extract regenerated inflorescences.Compared with the control group,the flowering period of the regenerated inflorescences was delayed by 30-35 d and 40-50 d,respectively;the harvest time was delayed by 30 and 40 d,respectively;the yield significantly increased by 1.63 times and 2.25 times,respectively;compared with the control group,the number of fruits with embryo increased significantly,which were 1.39 and 2.25 times of the control,respectively;there was no significant difference in the fruit quality at the harvest time.[Conclusions]Short-cut flowering branches at the initial flowering stage and full flowering stage of the primary inflorescence is an effective measure to delay the marketing time of Guire No.82 Mango.

Effect of Postharvest Treatments on Quality and Shelf Life of Mandarin (Citrus reticulata Blanco)

Nepal produces large quantity of mandarin (Citrus reticulata Blanco) annually but faces big losses due to improper postharvest treatments. The experiment was carried out during 2012-2013 with the objective of assessing the effect of different postharvest treatments on quality and shelf life of mandarin. The postharvest treatments were: wax emulsion at 10%, bavistin at 0.1%, wax at 10% with bavistin at 0.1%, calcium chloride at 1%, Jeevatu at 5% along with untreated fruits as a control. The experiment was conducted for four weeks of storage at ambient condition in Nepal Agricultural Research Council, Khumaltar, Kathmandu. Wax in combination with bavistin was found as the most effective in reducing the physiological loss in weight, whereas bavistin proved to reduce decay loss up to four weeks of storage. The fruits treated with wax alone and with combination of bavistin retained maximum firmness, juice percentage, vitamin C and palatability rating during the storage. The minimum total soluble solid and maximum titrable acidity were recorded in the fruits treated with wax plus bavistin. The present findings indicate that mandarin can be stored up to four weeks when treated with wax as well as wax with bavistin in the condition with 14&deg;C - 18&deg;C temperature and 45% - 73% relative humidity.

Comparison of Fruit Quality Characteristics of Berries

Fruits including berries are one of the most important sources of our daily nutrition due to their major aspect from point of view of consumers. The fruit quality includes the internal and external properties. The internal quality mainly is determined by aroma, flavor, taste, texture, nutritional quality (soluble sugar content, starch, organic acids, soluble solids content, and carotenoids, total flavonoids, total phenolic, antioxidant activity), flesh firmness, diseases, and chemical residues, while the external quality mainly concerns the appearance, size and colour and bruises. How to measure berry fruit quality has always been one of the most attractive research hotspots in the food industry. For the present, most of the available investigative methods are still destructive, labor and time-consuming;besides, several methods require sample preparation, costly instruments and chemicals, which cannot be used for large-scale sample evaluation. With the increasing demands of real-time detection of fruit quality, non-destructive fruit evaluation methods have been greatly developed. However, problems like low detection accuracy and poor model adaptability remain in the non-destructive detection system. Thus, it is necessary to develop non-destructive, high-efficient, simple, accurate and low-labor-cost techniques for fruit quality determination. In this paper, a comparison of different and advanced analytical methods for assessing the fruit quality characteristics of berries was discussed.

采后果实表皮蜡质结构、功能及其调控——综述与展望

表皮蜡质在植物果实生长和贮藏中发挥着重要作用。蜡质是覆盖在果实表皮细胞最外层不溶于水的物质,主要包括超长链脂肪酸(VLCFA)及其衍生物(酯、初级醇、次级醇、醛、酮等)和三萜。这种复杂的脂类化合物在大多数植物表皮细胞中合成并转运至细胞表面。蜡质不仅有利于果实免受微生物侵染,还能减少果实的机械损伤,从而保持果实的商品价值。迄今为止,关于果实蜡质的研究多集中于采前果实蜡质的变化、功能和调控,而忽略了果实采后贮藏过程中蜡质变化及生物学功能。本文对果实表皮蜡质组成、结构及其代谢调控进行综述。重点阐述影响蜡质组成的采后因素,如贮藏温度、相对湿度(RH)、气体环境、外源激素等,以及蜡质对果实采后品质的影响,包括水分散失、果实软化、生理失调、抗病性等。这些总结可能有助于更好地了解采后果实表皮蜡质变化及其在果实品质保持中的作用。