Site and fruit maturity influence on the quality of European plum in organic production

Information available on the role of site and fruit maturity in the quality of European plums in organic production has not been studied to date. European plum cv. ‘Green Gage’ grown in organic production was harvested in order to study the effect of site and fruit maturity on fruit quality. At harvest, significant differences were found in fruit weight, colour, firmness and TSS between harvest dates, whereas significant differences were found in fruit weight, colour, firmness and fruit Ca content between sites. Differences remained during storage. Fruit weight loss during storage was affected by site. Fruit with high Ca content showed higher firmness both at harvest and during storage. Harvest moment should not be chosen according to date, since differences between sites at the same date have been found. Firmness and colour parameters a* and h° would be useful to distinguish maturity at harvest between different sites and harvest dates. Linear regression between h° and firmness at harvest would allow the use of the h° colour parameter as a non-destructive measurement to distinguish maturity. Organic orchards should keep a minimum level of Ca in order to assure a slower fruit softening during storage.     

Yield and fruit quality of ‘Gala’ and ‘Fuji’ apple trees protected by white anti-hail net

Covering apple orchards with nets protects them from hailstorms but this changes the amount and quality of the light supplied to the trees. This study was carried out to assess the effects of shade provided by white protection net on yield and fruit quality of apple orchards in Southern Brazil, along three growing seasons (2002/2003, 2003/2004, and 2004/2005). ‘Gala’ and ‘Fuji’ apple trees (on MM111 rootstock, raised as slender spindles, with a spacing of 5.5 m × 3 m) were left uncovered (control trees) or covered with white net. The white net reduced the photosynthetically active radiation (λ = 400–700 nm) accumulated over the trees’ canopy along a day by 18.4%, leading to a higher leaf chlorophyll content in both cultivars, and a higher specific leaf area in ‘Gala’. The shade provided by the net did not affect yield and increased fruit average weight in both cultivars. At harvest, the number of seeds per fruit and severity of russet were not affected by netting in both cultivars, as well as the incidence of watercore in ‘Fuji’. The main beneficial effects of the white net were the reduced incidence of sunburn on ‘Gala’, reduced incidence of bitter pit during cold storage in both cultivars, and reduced incidence of apple scab at harvest and of decay after cold storage in ‘Fuji’. Fruit fly damage in ‘Gala’ (assessed in one season) was reduced by netting. However, netting affected negatively some fruit quality attributes. ‘Gala’ and ‘Fuji’ apples from trees protected by the net had a poor skin color (pale blush and a more intense green background color) at harvest. The net reduced flesh firmness and SSC, and increased the starch index of ‘Gala’ apples at harvest, and reduced flesh firmness and SSC, assessed after cold storage and shelf life, in fruits of both cultivars.     

Optimising quality-parameters of apple cv. ‘Pigeon’ by adjustment of nitrogen

To improve the productivity and quality of the apple cultivar ‘Pigeon’ the influence of 5 fertigation levels (14, 42, 70, 112, 224 mg N/l) and 3 widths of herbicide strip (0.2, 0.5, 1.0 m) were investigated on growth, yield and post-harvest quality/colour development of fruit. ‘Pigeon’ apples are picked when ca. 20% of the fruit skin has turned red, the fruit are then exposed to a sunning period on the orchard floor of 2–3 weeks to enhance red colour development (80% red skin); however the internal quality deteriorates during this period. Fruit drop occurs if fruit are left on the tree to develop colour. This study focused on how to reduce the length of the post-harvest sunning period to maximise both colour development and fruit quality. It was demonstrated that 14 mg N/l resulted in a low yield, small fruit, low vegetative growth, and low N content in leaf dry matter, but good fruit colour development. Excessive N fertigation (224 mg N/l) did not produce the significantly highest yield or the largest fruit, but it did enhance vegetative growth and resulted in less fruit colouration. N fertigation influenced optimal picking date; higher N fertigation delayed the time of picking, and increased the incidence of green fruit. Fruit from the high-N treatments required more days of post-harvest sunning to obtain the comparable red skin colour than fruit from the lower N-treatments. However, when all treatments were picked at ca. 20% fruit coloration it was not possible to reduce the length of post-harvest sunning period by N-supply. Most of the post-harvest colour development occurred within the first 6–9 days following harvest; colour developed on both sides but was enhanced on the shade side of the fruit. The shade side of the fruit had a greater potential for better red colour development than the blush side of the fruit.     

Responses of pepper to deficit irrigation for paprika production

Pepper (Capsicum annuum L.) production is normally carried out under irrigation as the crop is very susceptible to water shortage. Deficit irrigation strategies in pepper for paprika could increase production and facilitate mechanical harvest and, at the same time, save water. We conducted a field experiment that imposed water deficits, either during ripening (T1) or throughout the season (T2), and compared them to a fully irrigated control (T3). Stem water potential varied from −0.6 MPa in T3, early in the season to −1.5 MPa in T2 prior to harvest. Applied irrigation water for T1, T2, and T3 was 456, 346 and 480 mm, respectively. Water deficits depress leaf area and biomass production but did not affect the proportion of flowers that set fruit. Dry fruit weight in T2 at harvest was 66% of T3, but did not differ significantly between T1 and T3. However, commercial yield (based on colour production) was significantly higher in T3 than in the other two treatments, as the late water deficits imposed in T1 delayed harvest. We concluded that water deficits, either sustained or applied at fruit ripening, required for mechanical harvest do not hasten ripening and are detrimental to commercial yields and that pepper plants should be well supplied with water until harvest for maximum paprika production.     

Sensitive stages of fruit and seed development of chili pepper (Capsicum annuum L. var. Shishito) exposed to high-temperature stress

The sensitivity of developmental stages to high temperature was investigated in chili pepper (Capsicum annuum L. var. Shishito). Plants were subjected to heat stress (38/30 °C day/night) immediately after anthesis for 5 or 10 days, or from 10 to 30 days after anthesis (DAA), from 30 DAA until harvest of the seeds, or immediately after anthesis until harvest of the seeds. Control plants were grown at 30/22 °C (day/night). Exposure to high temperature (heat stress) during different periods of development after anthesis adversely affected fruit growth, seed yield, and seed quality in chili pepper. Heat stress for the whole period after anthesis, and from 30 DAA until harvest reduced the growth period of chili fruits by 15 and 10 days, respectively. Heat stress from 10 to 30 DAA reduced fruit width and fruit weight. The early stage of seed development from anthesis until 10 DAA was sensitive to high temperature, which affected fruit length, fruit weight and seed set. Applying high temperatures to plants for 10 DAA increased the proportion of abnormal seeds per fruit. High temperatures from 10 DAA until 30 DAA inhibited carbohydrate accumulation and adversely affected seed germinability and vigor. These results suggest that the stage of development at which chili peppers are exposed to high temperatures is an important factor in fruit and seed growth and in seed quality.     

Preharvest aminoethoxyvinylglycine treatments reduce internal browning and prolong the shelf-life of early ripening pears

The effect of aminoethoxyvinylglycine (AVG) on internal browning (IB) and keeping quality of early maturing European pears cv ‘Camusina di Genova’ and ‘Camusina di Bonarcado’ was examined over 10 days of storage at 18 °C. AVG was applied at 125 or 250 mg/L 2 weeks before harvest. At harvest fruit treated with AVG was less ripe than control fruit, being significantly firmer and experiencing lower values of maturity stage (based on ground color), maturity index (calculated value) and IB, depending on the AVG dose and cultivar. During storage, there was no treatment-dependent difference in titratable acidity and total soluble solids of juice, while both treatments reduced ethylene and respiration rates, delayed the ripening process and lowered the incidence of IB and the loss of firmness, especially when applied at 250 mg/L. In addition, AVG treatment significantly reduced decay development in both cultivars, mainly when it was applied at 250 mg/L. This effect was related to the delay of ripen and to possible inhibition of ethylene production by the pathogens and/or infected tissues.     

Effect of organic treatments with calcium carbonate and bio-activator on quality of ‘Reinette’ apple cultivars

‘Reinette du Canada’ (RC) and ‘Reinette Grise du Canada’ (RG) apple (Malus × domestica Borkh) cultivars declared throughout the Community as Protected Designation of Origin ‘Manzana Reineta del Bierzo’ are severely affected by bitter-pit during storage. Pre-harvest treatments with calcium carbonate, authorized in organic production, and bio-activator Harpin protein were used to assess the effect on quality at harvest and during cold storage in both apple cultivars during 2007 and 2008. Bitter-pit at the end of storage was higher in ‘RC’ than in ‘RG’, due to the fact that K/Ca ratio in fruit was higher in ‘RC’. Harpin protein did not improve the quality of ‘Reinette’ apple cultivars. Calcium carbonate pre-harvest treatments were useful to decrease external and internal bitter-pit incidence of ‘Reinette’ apple cultivars after 90 days of storage, but differences at the end of storage were not significant. Therefore, calcium carbonate would be a useful product in organic production in order to decrease bitter-pit incidence in ‘Reinette’ apple cultivars during medium term storage.     

Grafting effects on postharvest ripening and quality of 1-methylcyclopropene-treated muskmelon fruit

In addition to managing soil-borne diseases in muskmelon (Cucumis melo L.) production, grafting with resistant rootstocks may impact fruit quality. The ethylene antagonist 1-methylcyclopropene (1-MCP) has been shown to extend shelf life of fresh muskmelon fruit. Postharvest characteristics of 1-MCP-treated melon fruit as affected by grafting, however, have not been well examined. This study was conducted to explore the influence of grafting with different rootstocks on ripening and quality attributes of 1-MCP-treated muskmelon fruit during postharvest storage. Grafted ‘Athena’ muskmelon with two commercial squash interspecific hybrid rootstocks including ‘Strong Tosa’ and ‘Tetsukabuto’ as well as non-grafted and self-grafted ‘Athena’ were grown in replicated field plots at the University of Florida Plant Science Research and Education Unit (Citra, FL, USA) during April–June 2010. Half-slip fruit from two harvests were treated with 1.0 μL L⁻¹ 1-MCP (18 h, 20 °C) and analyzed during storage at 13 °C. For fruit from the 27 May harvest, whole fruit and mesocarp firmness, titratable acidity, soluble solids, and ascorbic acid content were measured, while production of ethylene and CO₂ was determined on fruit from the 29 June harvest. Grafting did not show a significant impact on fruit yield but affected the fruit shelf life significantly. Fruit from non-grafted ‘Athena’ and ‘Athena’ grafted onto ‘Strong Tosa’ demonstrated a shelf life of 31 d for the first harvest and 22 d for the second harvest. Shelf life of fruit from self-grafted ‘Athena’ and ‘Athena’ grafted onto ‘Tetsukabuto’ declined by 6 d and 3 d for the first and second harvest, respectively. Whole fruit firmness decreased by approximately 15.5% on average from 13 to 31 d except day 19 as a result of grafting, but to a lesser extent with ‘Strong Tosa’ rootstock. Mesocarp firmness of grafted melon was reduced by about 30.2% at days 13 and 19 compared to non-grafted ‘Athena’ fruit. In contrast, titratable acidity, soluble solid content, and ascorbic acid concentration were less affected by grafting. All the measurements except for ethylene and CO₂ production declined during storage regardless of the grafting treatment. Compared with ‘Strong Tosa’ rootstock, ‘Tetsukabuto’ resulted in a more rapid ripening under 1-MCP application, as reflected by earlier increase in ethylene production and higher respiratory rate. The study demonstrates that grafting effects on postharvest ripening and quality of ‘Athena’ muskmelon can vary markedly with rootstocks used.     

Partial rootzone drying maintains fruit quality of ‘Golden Delicious’ apples at harvest and postharvest

Partial rootzone drying (PRD) has been evaluated at harvest, but its effects on apple fruit postharvest life is little known for apples grown in semi-arid regions. The objective of this study was to test the hypothesis that water savings via PRD may affect fruit quality at harvest and postharvest-life of ‘Golden Delicious’ apples grown in a semi-arid region. The experiment was conducted from 2005 to 2007. The irrigation treatments were commercial irrigation as control (CI) and PRD. After 3 years of evaluation, fruit quality at harvest, measured as fruit weight, flesh firmness, and total soluble solids concentration, was similar between CI fruit and PRD fruit. Dry matter concentration (DMC) was higher in PRD fruit than in CI fruit in 2005. The fruit quality after 18 days storage at room temperature (13–18 °C and 51–56% relative humidity) was similar between CI fruit and PRD fruit. The DMC was the highest in PRD fruit in the 2005 and 2007 growing seasons, and tended to be higher in PRD fruit than in CI fruit in 2006. Total soluble solids concentration was ≈8.7% higher in PRD fruit than in CI fruit in 2007. Fruit weight loss was similar between treatments. This study suggests that water deficit via PRD did not damage fruit quality at harvest or after storage at room temperature. Additionally, PRD irrigation saved about 3240 m³ of water per hectare. Therefore, PRD can be recommended for commercial use in semi-arid regions and to those growers interested in either long-term storage or distant markets.     

Harvest and post-harvest apple fruit quality following applications of kaolin particle film in South African orchards

Sunburn on apples in the Western Cape region of South Africa can result in yield losses of up to 50%. Application of kaolin-based particle film (Surround^® WP) increases leaf and fruit surface reflectivity, thus potentially reducing heat load and sunburn. Trials were performed during 2002/2003 and 2003/2004 to assess the effectiveness of kaolin particle film in controlling sunburn on ‘Granny Smith’, ‘Braeburn’, ‘Fuji’, ‘Royal Gala’ and ‘Cripps’ Pink’ apples. Fruit quality and ripening were monitored following 1–4 months in regular atmosphere cold storage at −0.5 °C. Sunburn on exposed fruit was significantly reduced in ‘Granny Smith’ and ‘Fuji’. Kaolin treatment improved fruit colour of ‘Granny Smith’ and ‘Royal Gala’, and delayed starch conversion in ‘Granny Smith’ at harvest and during the early storage period but not thereafter. Incidence of watercore at harvest was significantly reduced by kaolin treatment, but this disorder disappeared during cold storage in both treatments. There were no effects on skin anthocyanin or phenolic concentrations in any cultivar compared to unsprayed fruit.     

Fruit thinning in ‘Conference’ pear grown under deficit irrigation: Implications for fruit quality at harvest and after cold storage

Fruit thinning in pear is feasible for mitigation of water stress effects. However, it is not well known how fruit quality at harvest and after cold storage is affected by pre-harvest water stress. Even less is known about the effects of fruit thinning on quality under these circumstances. To elucidate these, we applied deficit irrigation (DI) and fruit thinning treatments to ‘Conference’ pear over the growing seasons of 2008 and 2009. At the onset of Stage II (80 and 67 days before harvest in 2008 and 2009, respectively), two irrigation treatments were applied: full irrigation (FI) and DI. FI trees received 100% of crop evapotranspiration (ETc). DI trees received no irrigation during the first three weeks of Stage II to induce water stress, but then received 20% of ETc to ensure tree survival. From bud-break until the onset of Stage II and during post-harvest, FI and DI trees received 100% of ETc. Each irrigation treatment received two thinning levels: no thinning leaving commercial crop load (∼180 fruits tree⁻¹), and hand-thinning at the onset of Stage II leaving a light crop load (∼85 fruits tree⁻¹). Under commercial crop loads, DI trees were moderately water-stressed and this had some positive effects on fruit quality. DI increased fruit firmness (FF), soluble solids concentrations (SSC) and acidity at harvest while no changes were observed in fruit maturity (based on ethylene production). Differences in FF and acidity at harvest between FI and DI fruit were maintained during cold storage. DI also reduced fruit weight loss during storage. But fruit size was reduced under DI. Fruit thinning under DI resulted in better fruit composition with no detrimental effect on fresh-market yield compared to un-thinned fruit. Fruit size at harvest and SSC values after five months of cold storage were higher in fruit from thinned trees than fruit from un-thinned trees. Fruit thinning increased fruit ethylene production, indicating advanced maturity. This may lead to earlier harvest which is desirable in years with impending drought. Fruit thinning is therefore a useful technique to enhance pear marketability under water shortage.     

Influence of harvest time and after-ripening on the seed quality of eggplant

Eggplant cv. Emi and Tsakoniki were cultivated for seed in an unheated greenhouse and fruits were harvested at 25–65 days after anthesis (DAA) in order to determine the optimum harvest time. In addition, the effect of after-ripening on seed quality (i.e. seed size and germination) was examined by storing harvested fruit at 25 °C for 20 days prior to seed extraction. From the results, it was concluded that the optimum time of harvest for seed production is 55 DAA. Seeds extracted from fruits that were harvested at 25–35 DAA did not germinate, but when fruits harvested at the same age were stored for 20 days at 25 °C prior to seed extraction (i.e. seeds were after-ripened) germination was induced. Seeds extracted from fruits harvested at 45 DAA showed a high percent germination, which decreased after storage at 25 °C for 3 months. This decrease, however, was reduced by after-ripening prior to extraction. It is concluded that although eggplant is a non-climacteric species and fruit do not ripen after harvest, nevertheless seeds within the fruit continue to fill and mature after harvest; hence storage of prematurely harvested fruit prior to seed extraction permits the seeds of these fruits to after-ripen in situ and thereby increases seed size and germination. The implication of this result for eggplant seed production is discussed.     

Cropping effects on the loss of apple fruit firmness during storage: The relationship between texture retention and fruit dry matter concentration

Firmness is a primary measure of apple fruit texture, the key determinant of eating quality of apples. Despite the well developed understanding of the process of firmness loss in storage, there is very limited information concerning pre-harvest and at-harvest causes of the variation in fruit quality in the marketplace. The objective of the present study was to investigate the respective roles that the factors of time and intensity of crop thinning, fruit size and fruit dry matter concentration (DMC) each may have in determining fruit firmness of ‘Royal Gala’ apple at harvest and during storage. Loss of firmness during storage of all thinning treatments and of fruit size and DMC categories was described by a bilinear equation. Time of thinning did not influence any aspect of fruit softening during air storage at 0.5 °C. Comparing the crop loads, a lower crop load (100 fruit per tree) resulted in firmer fruit at harvest. The loss of firmness during storage associated with crop load occurred because fruit from the lowest crop load softened more rapidly during the second slow phase of softening. Fruit firmness was positively correlated with fruit size where larger fruit were slightly firmer than smaller fruit at harvest but not after storage. The softening profiles of different sized fruit were similar except for a class of extremely small fruit, which appeared to soften more rapidly during the second slow softening phase of storage. Both at-harvest and post-harvest fruit firmness were influenced by fruit DMC. Fruit firmness at harvest increased significantly as fruit DMC increased from 13% to above 16%. Despite having significantly different initial firmness, all fruit classes with DMC higher than 13% softened at a similar rate during both the initial rapid and second slow softening phases and the transition between the two phases occurred after the same time in storage. In contrast, fruit with very low DMC, less than 13%, had a greater rate of softening in the second phase. These results indicate that variation in fruit firmness at harvest and after storage is influenced by processes that affect and alter fruit DMC during fruit development. In this respect crop load control, which is used to improve fruit size, was also an important factor in altering fruit DMC, thereby affecting firmness at harvest and after storage. Furthermore, the effects of DMC on fruit firmness were independent of fruit size.     

The effects of pre-harvest dehydration on the composition of once-over harvested sweet paprika

When paprika fruits (Capsicum annuum L.) were allowed to dry in the sun, on the plant itself, before harvest, there was a considerable increase in the dry matter content of the subsequently harvested fruit, along with a decrease in the total fresh yield. The dry matter yield did not vary during the drying period, but the colour intensity of the fruit increased continuously. Early cessation of irrigation accelerated the drying rate and intensified fruit colour, but lowered the total dry matter yield.Removal of seeds, placenta parts and stalk after harvest increased fruit colour intensity but lowered yields.Leaving fruit to dry in the sun before harvest resulted in a considerable saving in transport and storage volume, as well in the amount of energy required otherwise to dry the fruit in the dehydration plant. It also opens up possibilities of once-over mechanized harvesting of high quality fruit.     

Improvement of quality and storability of apple cv. Aroma by adjustment of some pre-harvest conditions

To improve the quality of the important Swedish apple cultivar Aroma and increase its resistance to bruising and storage decay, three studies were conducted at Kivik research station during the period 1998–2003. The effects of tree age, pruning time and nitrogen fertilization were investigated. Fruits from young trees (younger than 6 years) had a lower resistance to bruising and Pezicula malicorticis decay, while fruits from trees older than 20 years seemed to show a quality and storability decline. Choosing a suitable summer pruning time was an effective factor for fruit storage potential. Thinning cut during August (5–6 weeks before harvesting) improved fruit colour and decreased decay without negatively influencing tree yield. Applying fertigation according to fruit development phase and soil nitrogen content had a very important influence on fruit quality and storability. Appropriate nutrition supply produced more deeply coloured fruit that maintained their quality after storage for 4 months. The bruising sensitivity of cv. Aroma apples was correlated with their N and K/Ca content. More coloured fruits showed less sensitivity to bruising.     

Evaluating variability of root size system and its constitutive traits in hot pepper (Capsicum annum L.) under water stress

The importance of root size system has long been recognized as crucial to cope with drought conditions. This investigation was conducted to: (i) evaluate the variability in root size system of hot pepper at maturity; (ii) estimate the effect of root size system on yield under drought conditions; and (iii) effect of water stress on xylem vessel development and total xylem cross-sectional area in roots of hot pepper cultivars. Twelve diverse hot pepper cultivars were grown in wooden boxes with two different water treatments, normal and in 50% water application as water deficit condition. Mean primary root length (PRL) showed a significant positive correlation with final fruit yield at normal as well as stressed condition. Total dry mass of fruit was reduced by 34.7% in drought treatments (DI) compared to full watered treatment (FI). At harvest, water-stressed plants had 21% lower root dry weight mass but higher root:shoot ratio other than FI. PRL, lateral root density, total xylem area per root cross-section showed a significant positive relationship with fruit yield. Also, lateral root density was higher in cultivars with higher xylem density, particularly in tolerant cultivars. Lateral root density (r = 0.847, P < 0.001) and total xylem cross-sectional area in root (r = 0.926, P < 0.001) were tightly related with total biomass production. The importance of root traits contributing to withstand drought in hot pepper is discussed.     

Cucumber fruit quality at harvest affected by soilless system,crop age and preharvest climatic conditions during two consecutive seasons

Cucumber fruits (Cucumis sativus L., cv. Trópico F1) grown on perlite substrate and NFT (Nutrient Film Technique) were harvested during two seasons (winter and spring) to monitor the effects of climatic conditions and hydroponic growth systems on fruit quality at harvest. The best fruit quality at harvest, as measured by lightness and hue angle parameters, was obtained during the 3 weeks following the first winter picking. When values of a parameter of preharvest climate value called G^* were lower than 0.4 MJ m⁻² °C day⁻¹ interval⁻¹, the cucumber achieved its optimum quality at harvest, as measured by the dark green color of the skin. NFT-grown fruits showed darker and greener skin color (higher hue angle and lower lightness) compared with perlite-grown fruit, irrespective of the season considered. During the winter season, the plant transpiration rate was 30% higher in perlite than in NFT culture, which correlates with higher differences in G^* and 40% additional yield in perlite. However, in spring G^* was not sensitive enough to discriminate between the two hydroponic systems. In general, fruit quality at harvest in spring was lower than during the winter, due to flesh whitening, higher longitudinal and equatorial calibers, and slightly higher pH, as well as worse epidermal color coordinates (ranging from the dark and dull green color typical of winter fruit to light and a vivid green-yellow color). During the spring season, NFT-grown fruit were less acid than perlite-grown fruit with no apparent correlation with the climatic conditions or fruit nutrition.     

Yield,blossom-end rot incidence,and fruit quality in pepper plants under moderate salinity are affected by K and Ca fertilization

One of the most important factors limiting agricultural expansion and production is the restricted supply of good quality water. The present study examines the effects of K⁺ and Ca²⁺ fertilization on sweet pepper production, blossom-end rot (BER) incidence and fruit quality of pepper plants (Capsicum annuum L.) grown under moderate saline conditions. Pepper plants were grown in a controlled-environment greenhouse under hydroponic conditions with different nutrient solutions obtained by modifying the Hoagland solution. The experiment consisted on four K⁺ treatments (0.2, 2, 7 and 14 mM) +30 mM NaCl, and four Ca²⁺ treatments (0.2, 2, 4 and 8 mM) +30 mM NaCl, having in common a control without salt with 7 mM K⁺/4 mM Ca²⁺. Salinity decreased total fruit yield and marketable fruit yield by 23% and 37%, respectively. The marketable fruit yield reduction by salt treatment was mainly due to the increase in the number of fruit affected by BER. This typical physiopathy of the pepper fruits occurred between 18 and 25 days after anthesis (DAA), when the highest fruit growth rate was reached. Fruit quality parameters were also affected by salt treatment where the fruit pulp thickness and firmness were decreased, and fructose, glucose and myo-inositol fruit concentrations increased with salinity relative to fruits from control treatment. Under saline conditions an increased supply of K⁺ reduced the fruit fresh weight, the percentage of BER and the marketable yield although promoted the vegetative growth. However, increasing Ca²⁺ concentration in the nutrient solution increased the fruit production, and the marketable yield as consequence of decreasing the percentage of fruit affected with BER. Fruit quality parameters also were affected by the K⁺ and Ca²⁺ treatments.     

The effect of fruit maturity on quality and colour shift of dried ‘Patterson’ apricot during eight months of cold storage

Summary

Fresh ‘Patterson’ apricot was harvested at three fruit maturity levels and characterized with measurements of flesh colour, Brix, acidity and levels of specific sugars. Fruit from the three maturity classes were sun-dried under uniform conditions. Dry fruit was again analysed for the content of specific sugars before cold storage. Stored fruit were sampled periodically for colour coordinates L*, C* and H° during an eight-month period. The study was repeated for two harvest seasons. In each season, significant differences (P≤0.05) were observed between the three fruit maturity classes for Brix, acidity, C* and H8. Levels of specific sugars varied significantly (P≤0.01) with regard to fruit maturity class, tissue type and fruit status. Regression analysis of colour coordinate changes during the storage period indicated significant (P≤0.05) differences in rate of colour shift of L*, C* and H8 relative to fruit maturity class. While dried fruit of the immature class was of substandard quality after the storage period, both medium and most mature dry fruit were of sufficient quality to warrant marketing even after eight months of cold storage.     

Effects of cultivar,orchard elevation,and storage on fruit quality characters of sweet cherry (Prunus avium L.)

Fruit quality characters were analysed in the sweet cherry cultivars, Burlat, Van, Tragana and Mpakirtzeika, harvested from low (39–59 m), medium (216 m) or high (490–546 m) elevation sites. The effects of storage for 2 or 4 days at 2 °C and 1 day at 20 °C on the fruit antioxidant contents were also evaluated. Tragana and Mpakirtzeika had greater fruit fresh weight (FW) and total soluble solid content compared to Van and Burlat, the latter being the most red colored. Tragana and Burlat had greater total phenolic content and total antioxidant capacity, measured by DPPH extinction, compared to Mpakirtzeika and Van (mean values 204.4 mg vs. 103.7 mg gallic acid equivalent 100 g⁻¹ FW, and 176.1 mg vs. 79.3 mg ascorbic acid equivalent 100 g⁻¹ FW, respectively). The geographic elevation had a marked influence on the cherry antioxidant content in all studied cultivars, apart from Van, with high elevation orchards producing cherries with greater contents of antioxidant compounds compared to lower elevation orchards. Changes in the antioxidant contents during storage were depended on the cultivar and some times on the orchard elevation. Total antioxidant capacity was significantly correlated with total phenolic content in Tragana, Burlat and Mpakirtzeika, but not in Van; nevertheless this was not the case during storage.