Light penetration,growth, and fruit productivity in ‘Fuji’ apple trees trained to four growing systems

The study was conducted to document the range in soil nutrients, trunk and shoot growth, leaf characteristics and nutrient content, flower bud characteristics, yield, fruit quality, disease occurrence, light penetration, and shoot bark color in a 15-year-old ‘Fuji’ apple (Malus × domestica Borkh.) orchard on M.26 rootstocks trained to four growing systems. SS trees naturally growing had greater width and volume than the LT lightly heading, MLT heavily heading, and S trees thinning and bending. LT trees had more upward terminal shoots at old branches, large numbers of lateral shoots, and longer total shoot length. Leaf [N], [P], and [K] were the lowest for the MLT trees. SS and S trees had greater flower bud density and fruit yield, but LT trees had poor fruit color and less soluble solids and firmness. Percent light penetration into the canopy was the highest with the S system but not different from MLT or SS. The lowest was for the LT system, however, it was not statistically different from MLT or SS.     

Postharvest changes in pigment concentrations in ‘Fuji’ apples with ‘Fuji’ stain

’Fuji’ apples (Malus domestica Borkh cv. ‘Fuji’) sometimes develop a discolouration in the peel during cold storage, typically in the periphery of sunburned peel. We refer to this particular postharvest disorder as ‘Fuji’ stain as we have not observed it in any cultivar other than ‘Fuji’ and the discolouration looks like a stain on the peel. Because peel discolouration occurs, peel pigments are thought to be involved. Hence the concentrations of anthocyanins, epicatechin, quercetin glycosides, chlorogenic acid, chlorophylls, and carotenoids in peel disks taken from areas exhibiting ‘Fuji’ stain were compared to concentrations observed in peel disks not exhibiting ‘Fuji’ stain. In 2005, peel from sunburned apples exhibiting ‘Fuji’ stain was compared to peel from three areas of sunburned apples not exhibiting stain [i.e. sunburned peel, the area around the sunburned peel (halo), and the area around the halo (OH)]. Additionally, stained peel was compared to the sun-exposed side of non-stained non-sunburned apples (NSNB). The second year, 2006, we compared stained peel to NSNB peel and the area outside the stained area (OS) on those fruit with stain. The concentrations of idaein, epicatechin, and quercetin glycosides were consistently low in the stained peel both years. This is in contrast to our earlier studies in which sunburned ‘Fuji’ apples had high concentrations of quercetin glycosides and epicatechin and low concentrations of idaein, and non-sunburned apples had low concentrations of quercetin glycosides and epicatechin and high concentrations of idaein. The consistent and unique characteristic of stained peel reported here indicates an association of these compounds with the incidence of stain. In 2005, chlorogenic acid concentrations in the stain peel were lower than other peel types, but in 2006 they were higher. Differences in chlorophyll and carotenoid concentrations were observed among many of the peel types. However, there is not a clear association between stain development and changes in chlorophyll and carotenoid concentrations due to significant differences not being observed in both years. While our research provides insight into pigment changes associated with ‘Fuji’ stain formation, more work is needed to help clarify the inconsistencies observed between the 2 years.     

The effect of reflective foil and hail nets on the lighting,color and anthocyanins of ‘Fuji’ apple

We studied the influence of covering the orchard floor with reflective foil on photosynthetic active radiation (PAR) both under and outside hail nets, and the possibility that the reflective foil under the hail net compensates for light reduction in last month before harvest time. On the lower side of fruit in the canopy, the reflective foil increased PAR. The chromaticity value a^* showed a difference in the intensity of red coloration in the reflective foil and hail net treatments. Amounts of individual cyanidins were detected by using HPLC–MS. The accumulation of five individual anthocyanins (cyanidin-galactoside, three cyanidin-pentoses and cyanidin) was investigated during last month before harvest time. Concentrations of the main, cyanidin-galactoside in ‘Fuji’ apple increased before harvest time, and at harvest time the reflective foil caused an increase in all identified anthocyanins.     

Differences in fruit colour development,anthocyanin content,fruit quality and consumer acceptability of eight ‘Gala’ apple strains

The effect of strain on fruit colour development, chromaticity values and anthocyanin content, fruit quality and consumer acceptance was evaluated on eight ‘Gala’ apple strains (Malus domestica Borkh.) at the IRTA (Spain), during a period from 4 weeks before to 1 week after commercial harvest. Based on fruit colour, measured with a Minolta CR-200 portable tristimulus colorimeter, and anthocyanin content, the most coloured strains were ‘Royal Beaut’, ‘Buckeye Gala’ (both semistriped) and ‘Ruby Gala’ (blushed). ‘Brookfield’ and ‘Schniga’ (both striped) provided an intermediate level of colour, while ‘Galaxy’ and ‘Mondial Gala’ (both striped) were the least coloured ones. The most important increase in colour development was recorded from 2 weeks before the commercial harvest and continued also increasing after harvest. Highly coloured strains developed a red colour on both fruit sides with greater average of fruit surface coloured, while the less coloured strains exhibited different colouration between sides, more bicolour fruits and lower average of fruit coloured.     

Delayed harvest improves red blush development and quality of ‘Cripps Pink’ apple

The poor red blush development on ‘Cripps Pink’ (Malus x domestica Borkh.) apple fruit at commercial maturity (CM) reduces the economic return to apple growers in warmer regions of the world. The effects of delayed harvest maturity up to 6 weeks following CM on the development of red blush and fruit quality of ‘Cripps Pink’ apple were investigated at two locations in Western Australia during 2003 and 2004. The red blush, export-grade fruit, total anthocyanin, cyanidin 3-galactoside, chlorogenic acid, catechin, and epicatechin of apple fruit skin tissues increased with advancement of harvest maturity at both locations in both years, whereas hue angle, concentration of phloridzin, fruit firmness, and titratable acidity (TA) of apple fruit tissues decreased with delayed harvest. The internal ethylene concentration was elevated with the delayed harvest. The concentrations of quercetin 3-galactoside, quercetin 3-arabinoside, quercetin 3-rutinoside, quercetin 3-rhamnoside, and quercetin 3-glucoside increased up to 2 weeks following CM, and then declined in 2003 at both locations and at Perth Hills in 2004. Delayed harvest resulted in improved development of red blush on the fruit surface, accumulation of total anthocyanin, cyanidin 3-galactoside, chlorogenic acid, catechin, epicatechin, and quercetin glycosides in fruit skin, SSC:TA ratio and reduced fruit firmness possibly due to the increased ethylene production.     

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.     

Influence of nine dwarfing apple rootstocks on vigour and productivity of apple cultivar ‘Granny Smith’

The influence of nine dwarf apple rootstocks (M.9 T 984, M.9 T 337, Jork 9, Mark 9, Budagowski 9, M.9 EMLA, Pajam 1, Pajam 2, and Supporter 4) on the vegetative characteristics, yield and yield efficiency, was evaluated on ‘Granny Smith’ apple variety (Malus domestica Borkh.).     

Fruit quality in ‘Cripp's Pink’ apple,especially colour,as affected by preharvest sprays of aminoethoxyvinylglycine and ethephon

‘Cripp's Pink’ apple grown in Western Australia often develops poor colour at commercial harvest resulting in economic losses. To determine if fruit colour could be improved without advancing ripening, ‘Cripp's Pink’ apple fruit on trees were sprayed with aminoethoxyvinylglycine (AVG) alone, ethephon alone, or AVG followed by ethephon. The experiments were conducted at two different locations in Western Australia in 2002 and 2003. Fruit sprayed with AVG alone had retarded colour development at harvest. However, ethephon applied after AVG enhanced percent red blush, anthocyanin concentration and reduced chlorophyll concentration in the fruit skin in both locations. These fruit had similar colour to those treated with ethephon alone. Internal ethylene concentration and fruit firmness were unaffected by the different treatments in 2002. However, in 2003 AVG with or without ethephon reduced internal ethylene concentration and maintained firmness compared to ethephon alone. In conclusion, AVG treatment alone delayed colour development and ripening of ‘Cripp's Pink’, while AVG application 5 weeks before harvest followed by an ethephon application 2 weeks later enhanced red colour at commercial harvest. This is, therefore, an effective tool for improving colour of ‘Cripp's Pink’ apples at commercial harvest without adversely affecting other fruit quality attributes.     

苹果果皮颜色性状的SSR标记

以24个苹果品种以及来自3个不同杂交组合的60个F1代结果单株为试材,对与苹果果皮颜色性状相关的DNA分子标记进行了研究。通过采用集群分类法(Bulked Segregant Analysis,BSA)对当前定位于苹果基因组图谱LG9上的所有SSR引物的分析,筛选到了一个与苹果果皮红色/非红色性状相关的SSR标记CN444542-156,该标记在红色表型上表现为隐性,在非红色表型上表现为显性。进一步分析表明,该标记对F1代单株性状预测的正确率为93.3%。     

Reflective materials under hailnet improve orchard light utilisation,fruit quality and particularly fruit colouration

The increase in hailstorms, possibly due to climate change, has led to installation of hailnets in fruit orchards worldwide. This is associated with poorer fruit quality, particularly fruit colouration, which is determined by the light conditions viz diminishing light intensities and shorter day length in the autumn. To overcome these adverse effects of hailnets, five materials were examined as possible ground covers as to their light reflection and the subsequent effect on fruit quality including fruit colouration, using a 9-year-old apple orchard cv. ‘Gala Mondial’ on M9 under black hailnet near Bonn. The ground covers included the woven white plastic Extenday^R/Daybright™, the kaolin-coated, bio-degradable paper UniSet O™ and the aluminium-coated plastic Mylar™ and Svensson ILS Alu™; the latter is a white plastic interwoven with aluminium strips used as energy saving screen in greenhouses. The ground covers were spread in the alleyways 4–5 weeks before anticipated harvest; adjacent uncovered grass strips under the hailnet served as control. Light reflection, measured perpendicular at 1 m height in the alleyways at the time of fruit colouration, was 79–80% by Extenday^R/Daybright™, 75% by UniSet O™, 68% by Mylar™ and 58% by Svensson Alu ILS™. Apple fruit with any of the reflective ground covers ripened 2–3 days earlier without affecting internal fruit quality and sugar as indicative of taste. The reflective ground covers under black hailnet improved the proportion of well-coloured class I fruit relative to the control (uncovered grass) by an averaged 9%. Economic analysis showed that Extenday^R, with an expected lifetime of ten years (based on 4–6 weeks spread time per year) under hail nets in North-Western Europe, scored best based on 45 t ha⁻¹ yield in cv. ‘Gala Mondial’ and 0.40 € kg⁻¹ farm-gate price, resulting in 200 € ha⁻¹ net return. Manual labour for spreading and retrieving the ground covers had the major share of the overall gross cost and offers scope for improvement by mechanisation.     

Fractal characteristics of two-dimensional images of ‘Fuji’ apple trees trained to two tree configurations after their winter pruning

The structural diagrams of apple trees are the comprehensive reflection of the effects of their training and pruning as well as their physiological and ecological characteristics and yield. However, there have been few research reports on the characteristics of the structural diagrams of apple trees. The study investigated the fractal dimension numbers and fractal characteristics of the two-dimensional images of 5-year-old and 10-year-old ‘Fuji’ apple trees trained to the tall spindle configuration and the open-center configuration employing box-counting in combination with the image processing technology of the Photoshop. The two-dimensional images of apple trees with the different configurations differed and varied with their ages. The fractal dimension numbers of the two-dimensional images of the 10-year-old apple trees with the tall spindle configuration and with the open-center configuration were 1.6625 and 1.6531 respectively while the fractal dimension numbers of the two-dimensional images of the 5-year-old apple trees with the tall spindle configuration and with the open-center configuration were 1.6429 and 1.6377 respectively. As the age of the apple trees increased, the spatial quantities and distributions of trunks and branches got slightly intensified, and the fractal dimension numbers of their two-dimensional images and the apple yield increased correspondingly. The comparison of the fractal characteristics of the apple trees with the same age, which were trained to the different configurations, revealed that under the same age, the branch quantities and the apple yield of the apple trees with the tall spindle configuration were higher than those with the open-center configuration, so that under the same age the fractal dimension numbers with the tall spindle configuration were higher than those with the open-center configuration. These results showed that the fractal dimension number of the two-dimensional images of apple trees depended upon their trunk and bough distribution and at the same time it increased with their apple yield as well. Therefore, the fractal dimension numbers of the two-dimensional images of apple trees could be employed as an indicator for assessing training and pruning effects on apple trees and their fruit yield.     

套袋对苹果果皮花青苷合成及着色的影响

套袋是提高苹果果实着色的主要技术措施之一,也是研究苹果果皮花青苷合成和基因表达的重要手段。苹果果皮花青苷的合成经由苯丙烷类代谢途径,编码苹果花青苷合成酶类的基因已得到克隆。套袋后果皮花青苷合成酶类的基因表达受到抑制,因而抑制了花青苷合成;摘袋后果皮花青苷迅速合成,与套袋后果皮光受体浓度增加和叶绿素含量降低从而提高对光的敏感度、迅速启动花青苷合成酶类的基因协同表达有关。果皮色素特别是花青苷和叶绿素的含量、比例和分布决定果实的着色状况,套袋促进果皮花青苷合成的同时大大降低了叶绿素含量,从而使果实着色鲜艳。     

金冠苹果树冠内光质构成及其与果实品质的相关性

应用CI-700AB/HR2000光纤光谱仪,研究了田间自然光照条件下金冠苹果树冠内的光质分布及其与果实品质的相关性。结果表明,UV-A、可见光、总辐射、紫光和蓝光,在树冠内分布从上到下、由外到内依次减弱,并与果肉总糖、抗坏血酸、果皮花青苷和类胡萝卜素的分布呈极显著正相关,与果肉可滴定酸和果皮叶绿素呈极显著负相关;UV-B与此相近,但与抗坏血酸呈不显著负相关;红外线则与可见光相反。     

Temperature affects color and quality characteristics of ‘Pink’ wax apple fruit discs

Red color plays a very important role when wax apple fruits are purchased. Temperature is one of the key factors among those influencing red color development. We evaluated the effects of temperature on color formation and other quality characteristics of ‘Pink’ wax apple fruit discs by using constant, slow-increase, fast-increase, transient shifting to high temperature, shifting to high temperature for different length of time and different day/night temperature regimes. The results show temperature has pronounced effects on quality attributes of wax apple fruit discs. Anthocyanin and total soluble solid (TSS) were greatest in the 20 °C treated discs under constant temperatures. In the slow-increase and fast-increase treatments, quality attributes in disc were better in treatments with a final temperature of 25 °C than of 30 °C. The concentration of soluble sugars (SS), starch, total phenolic compounds (TPC), free amino acids (FAA) and soluble protein (SP) all decreased with increasing temperature. Transient shifting to high temperature of 30 °C for 1-day had no effect on pigmentation but treatment periods from 3- to 5-days had a substantial adverse effect. At 30 °C for 5-days, exposed discs had the lightest weight and shortest diameter as well. Both SS and TPC decreased in the 3- and 5-day treatments. When temperature was shifted from 20 to 30 °C for 2 to 11 days, the widest and heaviest discs were found in the 5-day treatment. Anthocyanin and TSS concentration decreased following increased length of exposure to high temperature. Pigmentation of discs exposed to high temperature treatment was worse than in uncultured controls. Both protein and FAA concentrations decreased after culture. Among the 5 different day/night temperature combinations, discs under 25/20 °C had the highest anthocyanin and TSS concentrations, while those under 30/15 °C had the worst.     

渭北3种不同类型苹果园冠层特征及光照特性

渭北果区正在推广的旨在提高果园通风透光条件的“大改形”技术已进行几年,为对其效果进行观察,应用WinsCanopy2004a冠层分析仪对陕西渭北3种不同类型苹果园冠层及光照的有关参数进行了测定。结果表明,3类果园的平均冠下总辐射偏大(透光率高),每666.7m2留枝量偏低,说明改形对改善树体的光照条件效果明显,但是改形偏重;中冠园果树的透光率最高,小冠园最低;大冠园果树的叶面积指数最大,当年生枝量与主枝数的比例最大。     

主干形桃树对光截获能力和果实产量品质的影响

以6a生八月脆桃为试材,在果实成熟期观测分析了2种树形(主干形和开心形)对光截获能力和果实产量及品质的影响。结果表明,2种树形同一层次的平均单果质量、着色指数、光洁度差异不显著;果实硬度和可溶性固形物有显著差异,果实硬度表现为主干形﹥开心形,可溶性固形物则表现为开心形﹥主干形。对光截获能力的影响表现为主干形>开心形;叶面积指数、果实产量指标均表现为主干形高于开心形;果实产量是开心形的2.11倍。桃树主干形是高光效、高产树形。     

Effect of fruit load on 9,10-ketol-octadecadienoic acid (KODA), GA and jasmonic acid concentrations in apple buds

The relationship between 9,10-ketol-octadecadienoic acid (KODA), GAs and jasmonic acid (JA) and flower bud formation influenced by fruit load in apples (Malus domestica Borkh.) was investigated. The endogenous KODA and JA concentrations in apical buds in plants subjected to flower thinning treatment (FTT), under which all flowers were removed were higher than those in plants subjected to heavy crop treatment (HCT), under which the number of leaves per fruit was adjusted to 20 from 60 to 120 days after full bloom (DAFB). In contrast, the gibberellic acid concentrations [total of gibberellin A₁ (GA₁) and gibberellin A₄ (GA₄)] in FTT plants were low compared with those in HCT plants. The result suggests that KODA and JA in contrast to GAs may have opposite effects on flower bud formation which is significantly influenced by fruit load in apples and that KODA and JA may also be associated with flower bud formation in apples.     

Effects of temperature on fruit thinning with ethephon in ‘Golden Delicious’ apples

The effect of temperature on the ability of 2-chloroethylphosphonic acid (ethephon), when applied at 20 mm stage of fruit development, to induce ethylene evolution of fruit and leaves and abscission of fruit and leaves was determined using 9-year-old root-bagged ‘Golden Delicious’/M.27 apple (Malus domestica Borkh.) trees in environment-controlled growth rooms. Ethephon at 400 μL L⁻¹ effectively thinned apples, and its thinning effect was not affected by increasing day/night temperature from 21.1/10 to 32.2/21.1 °C. Fruit ethylene evolution was enhanced by application of ethephon. Peak fruit ethylene evolution occurred 1 day after application of ethephon when day/night temperature was 32.2/21.1 °C whereas it occurred 2 days after application of ethephon at a day/night temperature of 21.1/10 or 26.7/15.6 °C. Ethephon increased leaf ethylene evolution drastically but it did not induce leaf abscission regardless of temperature.