Fruit Flesh Firmness Research Articles

Effects of light availability and training systems on apple fruit quality

The correlation of light availability and fruit quality traits for apple fruits (Malus × domestica Borkh.) within the canopy in two training systems, Slender Spindle and Bi-axis, were tested on nine-year-old trees of 'Gala' grafted on M9 rootstock. Three trees were chosen for each training system and twelve fruits from each tree were selected in different canopy positions and labeled after fruit set. The light availability for each fruit was measured using a digital camera equipped with a fisheye lens. At harvest, fruit size, over color and quality traits were assessed for each monitored fruit. The results indicated a large variability of fruit light availability within the canopy depending on fruit position. The upper and outer fruit positions for both training systems resulted in significantly higher light compared to the lower and inner positions. The percentage of fruit skin color and the soluble solids content (SSC) were influenced by the canopy layers. Fruits in the upper tree positions had a higher percentage of over color and higher SSC, while no differences were found in the inner and outer positions. Fruit position didn't affect fruit size, ripening stage, and flesh firmness. The two training systems resulted in no differences for light availability or fruit quality traits.

Using absorption and reduced scattering coefficients for non-destructive analyses of fruit flesh firmness and soluble solids content in pear (Pyrus communis ‘Conference’)—An update when using diffusion theory

Quality attributes of fruit determine its acceptability by the retailer and consumer. The objective of this work was to investigate the potential of absorption (μa) and reduced scattering (μs’) coefficients of European pear to analyze its fruit flesh firmness and soluble solids content (SSC). The absolute reference values, μa* (cm−1) and μs’* (cm−1), of pear were invasively measured, employing multi-spectral photon density wave (PDW) spectroscopy at preselected wavelengths of 515, 690, and 940nm considering two batches of unripe and overripe fruit. On eight measuring dates during fruit development, μa and μs’ were analyzed non-destructively by means of laser light backscattering imaging (LLBI) at similar wavelengths of 532, 660, and 830nm by means of fitting according to Farrell’s diffusion theory, using fix reference values of either μa* or μs’*. Both, the μa* and the μa as well as μs’* and μs’ showed similar trends. Considering the non-destructively measured data during fruit development, μa at 660nm decreased 91 till 141days after full bloom (dafb) from 1.49cm−1 to 0.74cm−1 due to chlorophyll degradation. At 830nm, μa only slightly decreased from 0.41cm−1 to 0.35cm−1. The μs’ at all wavelengths revealed a decreasing trend as the fruit developed. The difference measured at 532nm was most pronounced decreasing from 24cm−1 to 10cm−1, while at 660nm and 830nm values decreased from 15cm−1 to 13cm−1 and from 10cm−1 to 8cm−1, respectively. When building calibration models with partial least-squares regression analysis on the optical properties for non-destructive analysis of the fruit SSC, μa at 532nm and 830nm resulted in a correlation coefficient of R=0.66, however, showing high measuring uncertainty. The combination of all three wavelengths gave an enhanced, encouraging R=0.89 for firmness analysis using μs’ in the freshly picked fruit.

Proposed descriptors for the evaluation of skin color, flesh firmness and juiciness, and sugar composition in Japanese persimmon breeding

Descriptors to evaluate fruit skin color, flesh firmness, flesh juiciness, and sugar composition using pollination constant non-astringent (PCNA)-type cultivars and selections of Japanese persimmon were proposed. A highly positive correlation was observed between the hue angle and color chart, and the skin color was classified as yellowish, hue angle ≥60°; orangish, hue angle between 51° and 59°; and reddish, hue angle ≤50°. Flesh firmness varied from 1.2 to 2.4 kg, and was classified as firm, ≥2.0 kg; medium, 1.4–1.9 kg; and soft, ≤1.3 kg. Flesh juiciness ranged from 0.18 to 0.39 mL g−1 FW, and was classified into very juicy, ≥0.30 mL g−1 FW; juicy, 0.21–0.29 mL g−1 FW; and slightly juicy, ≤0.20 mL g−1 FW. The analysis of variance for the flesh firmness, flesh juiciness, and sugar composition showed that the effect of genotype was large, while the effects of year, genotype × year interaction, among trees within genotype, and tree × year interaction were small or negligible. High varietal differences in sugar composition were found, ranging from 11.6 to 61.5% of the sucrose percentage. Furthermore, the sucrose to hexose (SH) ratio would be a useful descriptor for improving the palatability, especially sweetness, of PCNA-type persimmon fruits. The SH ratio ranged from 0.14 to 1.57, and was classified as very sweet, ≥1.00; sweet, 0.31–0.99; and less sweet, ≤0.30.

Response of Yield, Growth and Iron Deficiency Chlorosis of 'Santa Maria' Pear Trees on Four Rootstocks

This study was conducted on the 'Santa Maria' pear (Pyrus communis L.) budded on various rootstocks [pear seedling (Pyrus communis L.) and quince (Cydonia oblonga Mill.) (BA 29, QA and QC) rootstocks] under calcareous soil and semi-arid conditions during 2004-2012. The results showed that the highest cumulative yield per ha (53.1 t ha-1), fruit weight (304.1 g), fruit volume (337.2 cm³), fruit flesh firmness (22.3 lb.) and titratable acidity (0.21%) was obtained from trees on BA 29 rootstock. The highest SSC (15.8 %), cumulative yield per tree (78.08 kg tree-1), TCSA (79.03 cm²) and the lowest titratable acidity (0.18 %) were obtained from pear seedling. The most vigorous trees were grown on pear seedling, followed by 'BA 29', 'QA' and 'QC' rootstocks. The 'Santa Maria' pear variety's leaf chlorophyll content on all rootstocks fell during the study period up to 60 DAFB compared with 30 DAFB. It was found that leaf chlorophyll and Fe contents were higher in trees on pear seedling and BA 29 rootstocks and lower in those on 'QA'.

Accumulation of nutrients and agronomic performance of grafted seedless watermelon

ABSTRACT Chemical fertilizing is one of the main inputs that increase watermelon production costs. Watermelon grafting with compatible rootstocks and a vigorous root system may increase the efficiency of nutrients absorption. This study aimed at determining the accumulation of dry matter and nutrients, as well as the agronomic performance of grafted watermelon. The triploid 'Precious Petite' watermelon was used as graft and the Line BGCIA941 (Citrullus lanatus var. citroides) as rootstock. The experimental design consisted of randomized blocks, in a split-plot, with six replicates. The 'Precious Petite' grafted onto Line BGCIA941, ungrafted 'Precious Petite' and ungrafted Line BGCIA941 were evaluated in the plot, while the subplot corresponded to the sampling time (0, 10, 20, 30, 40, 50, 60 and 70 days after transplanting). 'Precious Petite' grafted onto Line BGCIA 941 accumulated more macro and micronutrients than the ungrafted plants, increasing fruit yield, flesh firmness and rind thickness, but it did not affect the soluble solids contents. The decreasing order for nutrient accumulation in the grafted plants was N > K > Ca > Mg > P > S > Fe > Mn > Zn > B > Cu, whereas for ungrafted 'Precious Petite' it corresponded to N > K > Ca > Mg > P > S > Mn > Fe > B > Zn > Cu.

Preliminary studies of genom-wide association mapping for some selected morphological characters of watermelons

Developing more efficient tools for watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai) breeding programs may greatly contribute to genetic improvement. The aims of this study were to investigate genome-wide association analysis (GWAS), and to develop regression models for some important watermelon traits such as yield, fruit weight, flesh color, total soluble solid, seed coat color, seed length and flowering time using 96 lines selected from 258 pure lines. An initial analysis was conducted to reduce sample size to 96 in order to avoid identical, highly similar and distant relatives causing low level of polymorphism and rare alleles. These 96 lines were morphologically and genetically characterized for several morphological characters under the eastern Mediterranean conditions, Adana, Turkey and PCR-based molecular markers. Associated markers were estimated by TASSEL program based on general linear model and a regression model because each trait was established through backward regression procedure nested in the SAS program. Levels of variation explained by regression models were 41% with 6 markers for flesh color, 22% with 2 markers for fruit weight, 48% with 5 markers for total soluble solids, 21% with 6 markers for seed size, 9% with 4 markers for fruit flesh firmness, 39% with 6 markers for 50% flowering time. This first report of GWAS for the selected characteristics of watermelon indicated a great potential to increase the efficiency of breeding programs.

YAPRAKTAN ÜRE UYGULAMASININ FARKLI ARMUT (PYRUS COMMUNIS L.) ÇEŞİTLERİNDE VERİM, MEYVE KALİTESİ VE BİOAKTİF BİLEŞİKLER ÜZERİNE ETKİSİ

The effects of foliar urea treatment on yield, fruit quality and bioactive compounds of three different pear cultivars (Akca, Santa Maria and Deveci) were investigated in this study. Whole trees were sprayed twice with an aqueous solution containing urea (0% and 0.1% CH 4 N 2 O) 30 and 60 days after the full bloom for each cultivar separately. The per tree yield, fruit weight and geometric mean diameter were significantly increased with urea treatment according to control. The color characteristics, soluble solids content, pH and titratable acidity didn’t change with the urea treatment. The urea treatment significantly reduced fruit flesh firmness. Urea treatment significantly reduced total phenolic content of Santa Maria. Total antioxidant activity of all varieties significantly reduced with the urea treatment. Urea treatment significantly increased naringenin content of Akca and Santa Maria, and rutin content of Deveci pear. The nitrogen content of the pear varieties was significantly increased with urea treatment. Additionally, urea treatment significantly increased zinc content of Deveci, and potassium, calcium and magnesium content of Santa Maria pear. Keywords: Pear, urea, phenolic, mineral nutrient, yield

The effect of different concentrations of pre-harvest gibberellic acid on the quality and durability of ‘Obilnaja’ and ‘Black Star’ plum varieties

The research work aimed at investigating the effect of pre-harvest gibberellic acid (GA3) treatment on the quality of ‘Obilnaja’ and ‘Black Star’ Japanese plum varieties. GA3 was sprayed onto the trees during the fruit color break at 0, 25, 50, 75, and 100 ppm concentrations. After pre-cooling, the plums were placed in modified atmosphere packages and exposed to the following conditions as follows: short storage-transportation (ST) [20 days at 2 °C and 90% relative humidity (RH)]; distribution center (DC) (5 days at 6 °C and 80% RH), and shelf life conditions (SL) (2 days at 20 °C and 70% RH). Pre-harvest GA3 treatments increased the fruit weight and size. Treatment of GA3 at 50, 75, and 100 ppm increased the fruit flesh firmness and total soluble substances (TSS) values in both the plum varieties during storage, transport, and marketing; it also limited the weight loss during the marketing process. Treatment of GA3 had no significant effects on the color, titratable acidity (TA), and the total phenolic and antioxidant activity values of plums. Pre-harvest GA3 treatment at 50 ppm GA3 can be thus recommended for both the plum varieties due to its effect on the fruit quality.

Preharvest boron application and its relation with the quality of 'Galaxy' apples after harvest and controlled atmosphere storage

ABSTRACT: The aim of this research was to evaluate the effect of preharvest boron application on the physical and chemical quality of 'Galaxy' apples after harvest and in controlled atmosphere storage during eight months, plus seven days of shelf life at 20°C. The experiment was performed with two treatments applied on the field: [1] Control (fruit without boron application) and [2] Foliar application of boron (four applications of 1.5kg ha-1). Findings showed that the boron application promoted a higher ethylene production and respiratory rate and it application also reduced the flesh firmness in relation to the fruits without it. A similar result was obtained after eight months of storage plus seven days of shelf life. The preharvest application of boron makes it possible to harvest apples earlier due to the fact that it accelerates the fruit metabolism. However, the fruits end up presenting a lower storage potential as a result of the higher ethylene production, respiration rate, decay incidence, mealiness and a reduction of the healthy fruit percentage and flesh firmness after CA storage.

The effect of preharvest gibberellic acid applications on fruit quality of ʽAngelinoʼ plums during storage

High-performance preharvest treatments can ensure maintenance of quality during storage. In this study, gibberellic acid (GA3) was applied on the trees in the preharvest stage to study its effects on the storage potential of the ʽAngelinoʼ plums. The treatment was applied at 50 and 75mg/L concentrations, on the 8th, 10th, 12th and 14th ʽweek after anthesisʼ (WAA). The results of the GA3 applications on the ʽAngelinoʼ plum quality after 90 days of storage and an additional 2 days of shelf life showed a decrease in weight loss, with a corresponding increase in fruit flesh firmness, total soluble solids and titratable acidity with the treatment. The fruit skin hue values were higher in the GA3 treated plums, whereas no change was observed in the total antioxidant activity and total phenol contents. Overall, the effect of the preharvest GA3 application on the ʽAngelinoʼ plum quality during storage at 0±0.5°C and 90–95% relative humidity for 90 days was positive.

Changes of backscattering imaging parameter during plum fruit development on the tree and during storage

Laser light backscattering imaging (LLBI) as a novel approach appears to be a promising technique for monitoring quality of horticultural products. The aim of this research was to investigate the feasibility of the non-destructive LLBI technique for the evaluation of plums quality indices during fruit development on tree and during storage. Plums of two cultivars were harvested four times during fruit development. At commercial harvest, fruit were stored at 2±0.5°C (90±2% RH) for 28 days and 2 days at 20°C with five measuring dates during storage. Experimental methods involved conventional measurements, i.e. fruit firmness, skin color, soluble solids content, dry matter content, and normalized anthocyanin index (NAI), and non-destructive LLBI at two wavelengths: 532 and 785nm. The obtained backscattering images were characterized by variation of brightness of the backscattered light. As an objective measure full width at half maximum (FWHM) was calculated from these radial backscattering profiles. The reduction in FWHM532 was strongly correlated with the increase in anthocyanin content as indicated by NAI during fruit development. Furthermore, the increase in FWHM785 was strongly correlated with the decrease in fruit flesh firmness during fruit development on the tree and during storage. In conclusion, results suggest that the LLBI using appropriate wavelengths can be feasible for non-destructive prediction of NAI and firmness in plum fruit.

Quantitative evaluation of cucumber fruit texture and shape traits reveals extensive diversity and differentiation

For many years, cucumber (Cucumis sativus L.) has been genetically improved by breeders to meet consumer demands. A wide variety of cucumber cultivars, differing in fruit qualities such as texture and shape, are grown around the world, and several major cucumber types have been developed in different regions. We used several computer-aided evaluation methods to assess the diversity in fruit texture and shape traits among a wide variety of world cucumber cultivars. Firmness of fruit skin, placenta and flesh and crispness of flesh were evaluated quantitatively and objectively by analysis of puncture-test data (force-deformation curves). Fruit shape was also evaluated quantitatively and objectively by using elliptic Fourier descriptors (EFDs) and principal component analysis (PCA). Fruit firmness and crispness clearly differed among cultivars and growth stages. Flesh crispness scores were significantly higher in Japanese F1 hybrid cultivars, which maintained relatively high crispness even at maturity; in contrast, the crispness of the other type cultivars remained low at all stages. PCA of EFDs detected three major components of fruit shape variation: the ratio of length to diameter, the amount of swelling at the fruit ends and the shape of the stem end. Significant differences were detected in these shape components among cultivars and cucumber types. These results indicate that quantitative differentiation has occurred in the fruit texture and shape traits of cucumber during domestication and subsequent breeding.

Combined effects of oxalic acid treatment and modified atmosphere packaging on postharvest quality of loquats during storage

Effectiveness of two different (3 mM and 6 mM) concentrations of oxalic acid (OA) application in combination with modified atmosphere packaging (MAP) on skin browning, fruit skin color (L*, a*, b*) values, fruit flesh firmness, total soluble solids (TSS), titratable acidity (TA), ratio of TSS/TA, pH total phenolic content (TPC), total flavonoid content (TFC), organic acids and soluble sugars, and percentage of O2/CO2 change in Hafif Cukurgobek loquats stored at 5 °C for 30 days were evaluated. Findings indicated that skin browning was reduced by pre-storage OA application in loquats. Furthermore, OA treatment produced the promising effects of inhibiting increases in fruit firmness and maintaining higher levels of organic acids, TPC, and TFC. The results showed that higher (6 mM) concentrations of OA significantly limited both development of skin browning and increasing firmness, and it maintained quality and extended the life of loquat fruit postharvest.

Biochemical and pomological assessment of European pear accessions from Bosnia and Herzegovina

The research on 10 old and indigenous pear cultivars was conducted during 2012 and 2013 in Bosnia and Herzegovina. The following characteristics were determined: fruit weight, fruit length and width, stalk length and width, fruit flesh firmness; soluble solids content and total dry matter content of the fruit juice; pH, titratable acidity, vitamin C, total phenolics, total flavonoids and antioxidant activity of the fruit cell juice. On the basis of the Principal Component Analysis (PCA) of pomological fruit characteristics the studied cultivars were divided into four main groups. Based on the PCA of biochemical traits the studied cultivars can be divided into three groups. Extremely high phenolic content in the cvs Mioljnjača, Žutica, Poljakinja, Karamut and Gradišćanka recommends them for their inclusion in a breeding programme. The cvs Mioljnjača and Poljakinja are also characterised by large and firm fruit and since the antioxidant capacity affects the duration of fruit storage, it is expected that these traditionally grown varieties can survive longer and keep their valuable nutritional ingredients longer.

Exogenous glycine betaine treatment enhances chilling tolerance of peach fruit during cold storage

The effect of exogenous glycine betaine (GB) treatment on chilling injury (CI), energy status, endogenous GB, γ-aminobutyric acid (GABA) and proline content in cold-stored peach fruit was investigated. The results showed that GB treatment significantly prevented CI and maintained low flesh firmness and high extractable juice in peach fruit during cold storage. The accumulation of endogenous GB, GABA and proline contents in peaches was enhanced by GB treatment resulting from increasing activities of metabolism enzymes, including betaine aldehyde hydrogenase (BADH), glutamate decarboxylase (GAD), Δ1-pyrroline-5-carboxylate synthetase (P5CS) and ornithine δ-aminotransferase (OAT). Moreover, high level of energy status in GB-treated peach fruit was found. These results indicated that GB treatment enhanced chilling tolerance in peaches due to induction of energy status, endogenous GB, GABA and proline contents, which prevented membrane damage. Thus, exogenous GB treatment could be a useful method to reduce CI in peach fruit during cold storage.

Effects of 1-methylcyclopropene (1-MCP) and modified atmosphere packaging on postharvest storage quality of nectarine fruit

The goal of this study was to compare the effects of modified atmosphere packaging (MAP), which is commonly used for the storage of nectarine fruit, and treatment with 1-methylcyclopropene (1-MCP: 0.5 or 1μLL−1 for 24h at 0°C), an ethylene inhibitor, on the quality of nectarines cv. ‘Maria Aurelia’. After harvest, nectarine fruits were subjected to 1-MCP or MAP treatments. Following the treatments, the fruits were then kept at 0°C for 40 days and at 20°C for an additional 2 days to simulate its shelf life. Fruit flesh firmness significantly decreased during storage and shelf life, for all treated fruits. Both 1-MCP doses and MAP maintained firmness better than control fruits. Chilling injury (CI) was first observed after 20 days at 0°C+2 days at 20°C and then further increased during cold storage and shelf life period for all treatments. Compared with control fruits, MCP treated or MAP-stored nectarines showed significantly reduced incidence of CI and polyphenol oxidase (PPO), polygalacturonase (PG) and pectin methyl esterase (PEM) activities as well as lower hue angles (h°), total soluble solid (TSS) contents and respiration rates. These results showed that both methods maintained the post-harvest quality of nectarine fruit and provided longer storage and shelf life.

Interaction of Crop Load and Irrigation on Yield, Fruit Size, Color and Stem-end Splitting Ratio of Apple c.v. ‘Gala, Galaxy’

In this study, the interaction between crop load and irrigation level on yield, fruit size, skin color and stem-end splitting fruit ratio in the apple cultivar ‘Gala, Galaxy’ grafted on rootstock M9 were investigated. Six irrigation programs were applied during the whole growth season: deficit irrigation (rates of 0.25 kc, 0.50 kc, 0.75 kc), full irrigation (rate of 1.00 kc), excess irrigation (rate of 1.25 kc) and non-irrigation (rates of 0.00 kc of “Class A” pan evaporation coefficient). Four crop loads in each irrigation application were performed by hand thinning after the June drop as a- a low crop load (3 fruits cm−2 TCA), b- a medium crop load (5 fruits cm−2 TCA), c- a heavy crop load (7 fruits cm−2 TCA), and d- an un-thinned crop load (> 7 fruits cm−2 TCA). The total tree yield increased with crop load and irrigation levels. Fruit size was significantly increased by the low crop load. Irrigation increased the fruit size compared to non-irrigation treatment. Further 0.75 kc, 1.00 kc and 1.25 kc irrigation treatments significantly increased the fruit length. Irrigation reduced the fruit flesh firmness. While the low crop load increased the skin red color, it decreased the fruit skin brightness. The yellowness of skin decreased with increasing in the irrigation amount. Irrigation reduced the skin brightness and yellowness, but it increased red color. Crop load and irrigation significantly affected the stem-end splitting fruit ratio. While the splitting fruit ratio increased with a decrease in the crop load, it decreased with an increase in irrigation amount, relatively. Consequently, the low and medium crop load treatments would be beneficial to increase the ratio of marketable fruits without any significant losses in yield for ‘Gala’ apple, especially under 0.75 kc deficit irrigation treatment.

Quality of cv. 'Gala Brookfield' and ‘Fuji Kiku 8' apples grown under and outside hail net

Anti-hail nets for the production of apples has become a normally action for a new or update an old apple orchard. In 2007 and 2008, the development of quality and maturity parameters of cv. 'Gala Brookfield' and ‘Fuji Kiku 8' apples grafted on M9 were studied in the Fruit growing centre Maribor-Gačnik as a factor of being grown under a blackhail net. The results showed that when grown under the black hail net fruit of both cultivars reach a higher mean mass, lower soluble solids content (0.6 to 1 ° Brix), and lower starch index, while no effect of the black hail net was detected on fruit flesh firmness and yield.

Phisico-Chemical Response of Seven Irrigated and Non-Irrigated Apple Fruit Varieties to Different Storage Conditions

Apple fruits are among the most consumed fruits in the world, an increased demand of good quality fruits being observed also during the winter and spring period, therefore the storage performance of apple fruits is a very important aspect for a good crop valorization. Fruit flesh firmness, fruit sugar content and its weight loss during storage are very important factors in assessing the quality of fruits, as well as their storage performance. The irrigation regime and the storage conditions are also very important aspects to fruit growers, as they can influence the yield, the quality and also the price for fresh fruits. Therefore, the interactions of these factors are studied, in order to observe the effects they have on the evolution of the three parameters for fruit quality, during the storage period.

A Spectroscopy-Based Approach for Automated Nondestructive Maturity Grading of Peach Fruits

This paper presents an automated approach for peach fruit maturity grading that, by exploiting fiber-optic spectroscopy-based sensors and multivariate processing techniques, minimizes the operator intervention while reducing discharge and waste. The use of a spectroscopic sensor complies with the so-called nondestructive measurement method, which enables fast repeated measurements to be performed at the single fruit level while avoiding fruit damage and loss. Maturity grading is accomplished by retrieving estimates of the fruit flesh firmness by means of multivariate retrieval techniques applied to the reflectance spectra acquired with the spectrometer and by processing the retrieved values within the framework of a maturity fuzzy classifier. A decision support system is developed to provide the user with maturity category decision and associated reliability. Experimental results show that the approach is effective for automated maturity grading of peach fruits affected by a high degree of variability. This paper lays the foundations for the realization of easy-to-use sustainable automated maturity grading systems.