Apfel oder Acai: Brasiliens Obstbau im ökonomischen und klimatischen Wandel

In times of recession with a 7–10% inflation rate, drop in consumption and loss in value of the Real currency, Brazil as the third largest fruit producer with 46 mil t fruit on 2.2 mil ha (2013), exports ca. 3% of its production worth ca. 765 mil (2013) – 807 (2014) US $, of which 80% is destined for Europe – the fruit export target for the future is 1 bil US $. Apple (cv. ‘Gala’ and ‘Fuji’) production under Southern hemisphere conditions (26–31°S) in Brazil rose from 0.6 mil t in 2002, peaked at 1.4 million t on 39,600?ha in 2011/12, declining in 2012/13 to 1.05 mil t due to orchard reductions in Fraiburgo as a result of lack of chilling, 1.16 mil t in both 20131/4 and 2014/15 and then 0.8 mil t in 2015/16 on 36,090?ha, resembling average apple yields in Germany on 31,400?ha.Apple orchards are essentially free of fire blight and codling moth, but with 1700?mm annual precipitation, they are affected by the scab and Glomorella fungi. Climate change affects apple production: Lack of chilling, caused by cold winters, induces vertical vegetative branches, flat speckled fruit with long pedicels (fruit stalks; cv. ‘Gala’), sunburn (cv. ‘Fuji’). Warm autumns result in a lack of fruit colouration in both varieties and prevent the cultivation of high chill apples, pears and plums.Three major fruit, orange (7.5?kg), banana (6.8?kg) and apple (cvs ‘Gala’ and ‘Fuji’; 4.2?kg apples/head/year; 2014) dominate the overall fruit consumption of 31.4?kg fruit/head/year compared with 36?kg beef, 34?kg pork and ca. 10?kg poultry resulting in ca. 80?kg meat/head/year in Brazil.In the last three years, a new range of storable apple varieties like ‘Venice’ and ’Daiane’ as well as ‘M 58/07’ and ‘M 10/09 – these latter two, still without a variety name – have been, like ’Eva’ added to the existing new breeds from EMBRAPA as very early variety (harvest in January; low chill; 150 CH) and to the summer varieties ‘Condessa’, ’Monalisa’ and ’Princesa’ (all 300–450 CH) without storability; red mutants of ‘Gala‘ (‘Gala, Maxi’ from RASIP) and of cv. ‘Fuji’ (‘Fuji Suprema’) both with 500–600 CH have been bred for growing in Brazil’s higher altitudes. The new cultivars provide medium-sized fruit, bright red peel colour and sweet taste with little acid and a sugar: acid ratio of 25–55:1, as required by Brazil’s domestic market, but so far lack market acceptance and a marketing concept.     

Ästhetische Premiumfrüchte trotz nasser Klimate – Obstbau in Südkorea

Horticulture Korea today earns 10 billion euros, to which fruit contributes 2.6 billion euros and vegetable production 6.7 billion euros. Apple, kaki, nashi, grape and Citrus contribute 100,000?ha to the overall fruit acreage of 188,000?ha. Koreas fruit industry stagnates and lacks trainees. The consolidation in the apple industry in the last ten years from 53,000?ha in 1995 to 26,000?ha today was due to over-sized aged trees on vigorous rootstocks and – by Asian standard – small-sized, sour, green and low-priced apple varieties like ‘Golden Delicious’. The new Korean cultivars ‘Hongro’ (12%) and ‘Kamhong’ (3%) supersede – apart from the major cv. ‘Fuji’ with a 65 % market share- late ripening and poorly coloured Japanese cv. ‘Tsugaru’ (8%) and ‘Kogetsu’ (5%). Apple harvest extends from August until mid November. The 200,000?t strawberries are from protected cultivation on 7,000?ha. Korea produces 2.3 million t fruit and is largely self-sufficient (84%) for fruit, except for bananas and Citrus, with 440,000?t imports and 33,000?t exports (Satsuma mandarins and Nashi to Taiwan and Japan) and 92% self-sufficiency for vegetables. Fruit consumption of 56?kg/head is half that in Germany with 120?kg/head and vegetable consumption with 170?kg/ha twice that in Germany of 90?kg/head. Apart from university research, the rural development agency (RDA) comprises a central horticultural research institute (NHRI) in Suwon with a dedicated apple (Gunwi, Daegu) and nashi (Naju) research station with extension service. Apples, peaches and nashi are bagged, particularly for export, to fulfil the fruit quality requirements. These comprise a cosmetic skin finish free of blemishes and lenticels, 250–400?g fruit mass, (dark) red colouration and sweet (13–18?° Brix) taste without acidity (0.3–0.4%), resulting in a sugar acid ratio of ca. 43?:?1 with farmgate prices of 2.4?€/kg and retail prices of 2.8–4.8?€/fruit. Historic, Japan inflicted, measures such as defoliating of fruit-bearing branches and bagging to protect the peel, which will be consequently removed with valuable nutrients, are now being questioned and re-considered. Overhead irrigation protects the orchards from frost and hence prevents alternate bearing. Korean apple orchards are devoid of apple scab (Venturia inaequalis), apple canker (Nectria galligena) and fire blight (Erwinia amylovora), despite large annual precipitation of 1,000–1,500?mm, and hence require few pesticides. With farm sizes of 0.8?ha, the 41,000 fruit farmers are not very mechanised; 3% of them subscribe to organic farming and a quarter to a voluntary IFP scheme. GAP is discussed, but QS-EUREP GAP quality schemes are not implemented given the large farm number and few fruit exports.     

Einfluss selektiver mechanischer Fruchtbehangsregulierung auf Ethylensynthese als Stressindikator sowie Ertrag und Fruchtqualität bei Kernobst

The overall objective of this work was to improve fruit quality, break alternate bearing and reduce hand thinning using fewer chemicals in fruit crops. A device was constructed for mechanical thinning, which consisted of three independent horizontal rotors with ropes and freely adjustable angles on a frame, mounted on a front three point hitch and powered by the tractor hydraulics. This can be adapted to any fruit tree trained as spindle, Solaxe, (tall) vertical axis or fruit wall (le mur fruitier) irrespective of rootstock employed. Rotor speed varied from 300 to 460?rpm at either 5 or 7.5?km/h tractor speed. Eight-year-old or twelve-old apple trees cvs. ‘Gala’ and ‘Golden Delicious’ were mechanically thinned in 2007 between pink bud and full bloom (flower bud stages 6–8 or F1–F2) near Bonn, Germany; non-thinned and hand-thinned apple trees of the same block and variety served as control. Mechanically thinned flowering branches showed a similar amount of ethylene efflux (0.4–0.6?ppm C₂H₄/branch) as non-thinned flower branches, preventing potentially unexpected subsequent fruit drop, except for those removed by the rotors. The impact of the horizontal rotors on the branches was from the upper side and removed excessive flowers right to the tree trunk viz. the centre of the tree canopy, where fruits of lesser quality are expected leaving 2–3 flowers per cluster. Leaf damage was less than??10%, even at the fast rotor speed of 420?rpm, which was associated with negligible wood injury. Mechanical thinning induced firmer and sweeter fruit, i.e. tastier apples with longer shelf life, relative to control fruit from non-thinned apple trees. The greatest efficacy in terms of final fruit quality in the grading/sorting was achieved by a rotor speed of 360?rpm at a tractor speed of 5?km/h: Fruit mass increased by up to 20?g and the proportion of fruit larger than 70–75?mm by 10–30% compared with the fruit from non-thinned trees. Mechanical thinning with this newly constructed device led to a 10–20% reduction in yield, but increased returns due to better fruit size and colouration in apple with the potential to overcome alternate bearing.     

Verfrühung von Süßkirschen im Folienhaus

Early ripening sweet cherry cvs ‘Burlat’, ‘Earlise’, ‘Samba’, ‘Souvenir des Charmes’ and clone M, which are all characterised by large fruit size and dark red fruit, on GiSelA 5 rootstock were forced – by closing a polytunnel from 24 March to 20 April 2006 – at Klein-Altendorf research station of Bonn University. A portable gas heater was used for automated frost protection in April. An adjacent uncovered planting at the same spacing of 3.8?m?×?1.75?m served as control. Forcing resulted in a 16–18 days earlier flowering in April relative to the 12–16 days earlier harvest at the beginning of June, resulting in a 2–4 days longer fruit development and retarded ripening. PAR was reduced in the polytunnel by 40% on sunny and 30% on overcast days with a concurrent drop in the humidity to 30% on sunny and 40% on overcast days and nearly 100% relative humidity at night. Polytunnel air temperatures on sunny days were increased – during ventilation – by up to 6?°C relative to the outside, e.g. 33?°C versus 27?°C outside. Forced cherries saved one spray application against aphids compared to those outside. Fully-grown cherry leaves contained 40–60?mg chlorophyll/g FM sufficient for photosynthesis with commensurate chlorophyll contents when grown in the polytunnel compared with those outside, and were deficient in calcium (0.5% DM) and magnesium (0.2% DM), but with a surplus in both nitrogen (3.5% DM) and phosphorus (0.42% DM). The surplus leaf nitrogen was due to excessive nitrogen mineralization in the rich soil under the higher temperatures in the polytunnel which caused the vigorous vegetative growth despite the dwarfing rootstock. Great fluctuations in fertilisation – despite strong flowering and sufficient pollination with honey bees – of between 4–71% may be due to the combination of S-alleles of the cherry varieties, infrequent water supply, nutrient imbalance and microclimate. Trees of cv. ‘Burlat’, ‘Earlise’ and clone M in their fourth leaf yielded an average of 2.5–7.5?kg fruit with 15?kg/tree in one case. Fruit of forced cvs. ‘Burlat’, ‘Souvenir’ and ‘Samba’ were larger compared with those of cv. ‘Earlise’ and clone M, which were smaller as a result of increased fruit load on the tree than those from uncovered control trees. For all five cvs tested, except forced cv. ‘Earlise’, a fruit mass of between 10?g (28?mm ) and 12?g (30?mm) and a sugar content of 12–17% with sugar:acid ratios of 20–37:1 made their fruit suitable for marketing as superior or premium fruit at higher farm-gate prices of 4.5–8?€/kg. Fruits were sufficiently dark red or black and firm for short distance transport and rapid sale. An economic evaluation showed financial gains, when yields exceed 8?kg fruit per tree per year at a farm-gate price of 4.50?€/kg.     

The role of Pre-harvest Aminoethoxyvinylglycine (AVG) Treatments on Total Phenolics,Antioxidant Capacity and Fruit Quality Attributes of Sweet Cherry Cultivars

The present study was conducted to investigate the effects of pre-harvest aminoethoxyvinylglycine (AVG) treatments on fruit quality parameters and bioactive compounds of sweet cherry fruits (Prunus avium L. cvs. ’0900 Ziraat’, ‘Regina’ and ’Sweetheart’). Whole trees were sprayed once with an aqueous solution containing AVG (0, 100 and 200?mg L^?1) three weeks before the anticipated commercial harvest. Measurements were performed a week before anticipated harvest date, at anticipated harvest date and a week after anticipated harvest date. AVG treatments significantly maintained flesh firmness of all three sweet cherry cultivars. Harvest was delayed at least for a week through the keeping of flesh firmness with AVG treatments. The treatments slowed down the red skin color development in all three cultivars. The measurements performed over fruits collected at different ripening stages revealed that AVG resulted in decreased total phenolics and total anthocyanin and ultimately decreased antioxidant capacity in sweet cherry fruits. AVG treatments also decreased soluble solids content and increased titratable acidity of the fruits. This study revealed that pre-harvest AVG treatments were more effective in delaying sweet cherry fruit softening. The main advantage is to maintain the firmness of late-harvested fruit by retaining fruit quality attributes of sweet cherry fruit.     

Comparison of Climate Change Effects on Pome And Stone Fruit Phenology Between Balkan Countries and Bonn/Germany

The objective of the joint project between the two universities of Bonn and Sarajevo was to study the effects of climate change associated with warmer winter and spring temperatures on fruit tree phenology. Changes in flowering date of apple and cherry were correlated with local weather data obtained concomitantly on-site at four locations in the Balkan countries Slovenia, Serbia, B & H and at Bonn, Germany.Phenological data of flower opening (F1; BBCH 61) of apple cv. ‘Golden Delicious’ originated from 55 years at Cacak (44?°N, Serbia) and at Klein-Altendorf, University of Bonn (50?°N), cv. ‘Bobovec’ from the University of Ljubljana (46?°N, Slovenia) and cherry cv. ‘Burlat’ (35 years at Klein-Altendorf, 50?°N) and 20–30 years at Tuzla (44?°N, B & H) and Mostar (43?°N, Bosnia & Herzegovina; B & H).The annual precipitation showed a negligible change in the last 55 years of ±5% in the Balkan countries (e.?g. Cacak, 699?mm), but only ±1.8% at Klein-Altendorf (605?mm) with a slight shift to more winter rainfall.Regression analysis showed an increase in mean temperature of 1.7?°C (annual) and 1.45?°C for the vegetation period at Klein-Altendorf (last 55 years), Germany. In the evaluated Balkan stations, the greatest increase in annual air temperature between two climate phases (until 1987 versus from 1988 until now) was at Ljubljana (1.4?°C) and Cacak (1.2?°C) in contrast to the least increase (0.3?°C) at Tuzla (annual average 10?°C) and an intermediate value (0.9?°C) in the warmer Mostar (annual average 14.5?°C).This recent temperature increase advanced flower opening by 10–14 days for apple such as cv. ‘Golden Delicious’ at Cacak and 7–10 days (last 55 years) at Bonn and 4–5 days (last 35 years) for the early cherry cv. ‘Burlat’ at Klein-Altendorf/Bonn; at Mostar and Tuzla, the effect of climate change was greater with the early cherry cv. ‘Burlat’ (26 days) compared with the difference of the late cherry cultivar (16 days). Before recent climate change (1973–1987), cherry flower was advanced by 10 days in the warmer med climate at Mostar but delayed by 16 days in the cooler Tuzla. The results, i.?e. the flower advancement in the Continental climate but flower delay in the med climate, are discussed with respect to the risk of late frost and countermeasures to combat climate change effects.     

Estimation of the Colour Properties of Apples Varieties Using Neural Network

The consumer acceptance and the quality standard of agricultural products such as apple are determined mostly by their colour. Colour is measured with a colorimeter and quantified using the C.I.E. L^*, a^*, b^* colour space system. It is used commonly by researchers for the classification and identification of apple fruit. To the best of our knowledge, the present study is the first study investigating the prediction of some colour properties of six apple varieties through artificial neural networks (ANN). The apple varieties are ‘Amasya’, ‘Starking’, ‘Granny Smith’, ‘Pink Lady’, ‘Golden Delicious’, ‘Arapk?z?’ and the colour properties are L^* (lightness), a^* (redness), b^* (yellowness), C^* (chroma), h^* (hue angle), CI (chroma index). General Regression Neural Networks (GRNN) and Adaptive Neuro Fuzzy Interface System (ANFIS) structures were employed to predict the colour properties. According to the experimental and simulation results, the proposed ANFIS predictor had a superior performance in prediction of these colour parameters.     

The Growth of Apple Central Fruits as Affected by Thinning with NAA,BA and Naphthenic Acids

Plant growth regulators such as α?naphthylacetic acid (NAA) or 6?benzyladenine (BA) are commonly used for thinning apple fruits. NAs exhibits an auxin- and gibberellin-type biological activity, stimulate the uptake and translocation of auxins in plant tissue, as well as IAA synthesis and act as surfactants. It was assumed that NAs applied at the stadium of early fruit growth might cause fruit abscission in apple, similarly to NAA. The goal of the research was to test the presumed thinning effect of naphthenic acids on apple cultivars ‘Golden Delicious’ and ‘Red Delicious’. Three treatments were applied on both apple cultivars including 16.5?μL L^?1 NAA, 200?μL L^?1?BA and 2.63?mg L^?1?potassium salts of NAs. Cortical cell size and the number of cell layers were measured in order to determine the contribution of cell size and cell division in early fruit growth, as affected by chemical thinning treatments. The effects of plant growth regulators NAA, BA and NAs on fruit set, fruit size and the anatomy of the fruit cortex highly depend on varietal differences. In ‘Golden Delicious’ fruit set reduction by chemical thinning increases both the number of cell layers and cell size of apple fruit, while in ‘Red Delicious’ NAA inhibits fruit growth, while BA is ineffective. Cell growth promoting activity of NAA and NAs, accompanied by the decrease in fruit set and reduced competition among fruits within the canopy, results in a significant fruit weight increase at harvest. The research confirms the auxinic properties of NAs, and their assumed thinning activity.     

Spezifisches Gewicht neuer Apfelsorten

At the Research Centre for Agriculture and Forestry Laimburg the specific weight of 121 apple varieties from the own variety collection was measured by a hydrostatic method (Archimedes principle) from 2007 to 2013. For this purpose samples of 10 apples per cultivar were collected mainly from the sites of Laimburg (220?m asl) and Laces (700 meters asl) and were examined annually at the same period with uniform fruits equal in size. The cultivars could be classified in specific weight classes from 0.75 to 0.91?g/cm³. 76% of the varieties were assigned to the middle classes since they had specific weights ranging from 0.80 to 0.86?g/cm³. ‘Golden Delicious’ was included within the specific “very light” varieties while ‘Braeburn’, ‘Nicoter Kanzi®’ and ‘Scifresh Jazz®’ were classified as “very heavy” varieties. The year and location do not significantly influence the specific weight, since this parameter depends rather on genetically caused factors such as the intercellular volume and the dry matter content of the fruit. The specific gravity can be an interesting complementary information to describe an apple variety.     

Storability of ‘Conference’ Pear Under Various Controlled Atmospheres

In two consecutive experimental seasons it was investigated the storage capacity of ‘Conference’ pear (Pyrus communis, L.) under regular air (RA) and various controlled atmosphere (CA) conditions during six months at 0?°C (±0.3). The occurrence flesh browning (FB), core browning (CB) and cavity formation (CF) was evaluated at each 2?months storage intervals and the ripening quality traits analyzed immediately at the end of storage period and after 7 days of shelf-life in air at 20?°C. The storage conditions were: RA; 0.5?kPa O₂?+?0.5?kPa CO₂; 1.5?kPa O₂?+?1.5?kPa CO₂, 2.0?kPa O₂?+?1.0?kPa CO₂; 3.0?kPa O₂?+?6.0?kPa CO₂ and 0.5?kPa O₂?+?6.0?kPa CO₂. After six months, ‘Conference’ pear was very susceptible to FB, CB and CF under CA-storage. The damages started to develop at the second month of storage, increasing continuously until end of storage period. At storage end, pear fruits kept under 0.5?kPa O₂?+?6.0?kPa CO₂ showed a dramatic high occurrence of FB, CB and CF with a severity index of 50.6, 45.3 and 27.1, respectively. The lowest incidences of FB, CB and CF were scored in fruits kept at 2.0?kPa O₂?+?1.0?kPa CO₂ with severity indexes of 1.1, 1.1 and 1.0, respectively. Flesh firmness, skin color, titratable acidity and total soluble solids were satisfactory under 2.0?kPa O₂?+?1.0?kPa CO₂. In conclusion, ‘Conference’ pear cannot be stored under O₂ partial pressure lower than 2.0?kPa and CO₂ higher than 0.5?kPa.     

Einfluss schwach wachsender Apfelunterlagen auf Wachstum,Ertrag und Fruchtgröße verschiedener Sorten – Teil IV: Abschließende Bewertung

From 2001 to 2005 the influence of the dwarfed apple rootstocks M?9 (clone: Burgmer 984), Fleuren 56, Supporter 1, P?16, P?22, J-TE-F, J-TE-E and M?27 on growth, yield and fruit size of the apple varieties ‘Elstar, Elshof’, ‘Boskoop, Herr’ and ‘Jonagored’ was investigated on the locations Auweiler, Dresden-Pillnitz, Osnabrück and Wurzen in Germany.All rootstocks induced a less vegetative growth as the rootstock M?9. In comparison with M?9 the crown volume of the trees ranged from 92% (Supporter 1) to 52% (M?27). The highest yield potential showed the rootstock P?16. Her specific yield (kg/m³) was 17% higher than the specific yield of M?9. All rootstocks produced a lower individual fruit size as M?9. J-TE-E and J-TE-F produced the lowest specific yield.     

Multi Criteria Assessment of Zero Residue Apple Production

During the 2008–2010 growing seasons, an alternative ‘zero residue apple production system’ was compared with integrated apple production with cvs ‘Idared’, ‘Golden Delicious’, ‘Jonagold’ and ‘Gala’ in commercial orchards at several locations throughout Slovenia, using data envelopment analysis (DEA), and multi criteria assessment by an analytical hierarchical process (AHP). The principle of the ‘zero residue apple production’ is a combination of integrated (IP) and organic apple production. During the first 3 months of the growing season (1 April–30 June), pesticides used in IP with rapid degradation (8–10 applications) were used to control pests and diseases. During the second part of the season from 1 July to harvest, organic products (6–12 applications) were employed compared with 19–25 applications overall in IP. The goal of the alternative system was to reduce the amount of applied conventional pesticides by 40 % and to minimize pesticide residues in fruits to below the limit of 0.5 % of the legal maximum residue level (MRL) or below the residue concentrations of 0.005–0.01 mg/kg and to retain the high long-term level of yield, fruit quality, and net income per hectare. The number of pesticide residues was reduced from 4.2–5.5 in IP to 1.8–3.4 in zero residue cultivation, while 3 year average yields (class 1 fruit) were 4–9 % lower than in IP. The break even prices ranged from € 0.31 for Idared in IP, € 0.34 for ‘Elstar’ of both production systems to € 0.35/kg for zero residue cultivated ‘Golden Delicious’. Overall, a price increase of just € 0.02/kg for residue free apples would make this new ‘zero residue apple production’ profitable then representing a realistic alternative to the standard integrated apple production system.     

三倍体梨新品种‘华香酥’

‘华香酥’是以‘沙01’与‘南果梨’杂交育成的三倍体梨新品种。树势强,树姿开张。平均单果质量180 g,果实倒卵形,果皮底色黄绿,阳面着淡红色;果肉乳白色,肉质松脆,较细,汁液多;可溶性固形物含量13.54%,可滴定酸含量0.13%,风味甜,微香,品质上等,耐贮性较强。在辽宁省兴城市9月中旬成熟,果实发育期140 d。盛果期产量39 000 kg ? hm-2。抗寒性较强,抗梨黑星病。     

Nicht-destruktive Erkennung von Berostung bei Birnen

The objective of the present study was to investigate possibilities of non-destructive examination of russet on pome fruit using a luster sensor (Mukhtar et al. 2014) including varietal, colour and positional influences. Therefore, pears of three varieties from the local market in December, were investigated by three means, visual observation of the type and spread of russet, 3D colour microscope and sensor technology.Visual oberservation showed that pears of cv. ‘Conference’ from Belgium exhibited the most severe russet, particularly in the spherical part of the fruit, but also with speckled russet at the elongated stalk end of the fruit. Pears of cv. ‘Alexander Lucas’ from Germany had the least russet localized at the calyx end of the fruit and those of cv: ‘Abate Fetel’ from Italy showed an intermediate level of russet at the calyx end.Three-dimensional colour microscopy at x200 magnification.showed that russet, i.?e. suberinisation of the fruit peel, on cv. ‘Conference’ caused a 2.5-fold increase in roughness of ca. 50 µm compared with ca. 20 µm on russet-devoid peel sections of cv: ‘Alexander Lucas’.Scarcely russeted peel of cv. ‘Alexander Lucas’ showed significantly larger luster levels and those of cv. ‘Abate Fetel’ the tendency of larger luster levels with a smaller variation than russet devoid fruit peel. Russet was more difficult to detect on the elongated part of the pear fruit next to the pedicel. These first results indicate that this sensor-based russet detection is based on a combination of peel roughness and colour; but require further investigations.The results of larger luster levels on russeted pears are in line with those on plums (Mukhtar et al. 2014) where polishing during harvest and postharvest handling doubled luster levels compared with the undisturbed natural amorphous fruit surface.     

Antimicrobial,Antioxidant, and Antimutagenic Activities of Five Turkish Pear Cultivars

The pear (Pyrus spp.) is one of the most important fruits consumed in daily life. The aim of this study was to determine the total phenolic and ascorbic acid contents, as well as the antimicrobial, antioxidant, and antimutagenic activities, of various pear cultivars. The fruits of five pear (Pyrus communis L.) cultivars (‘Deveci’, ‘Kizil’, ‘Egirsah’, ‘Gugum’, and ‘Banda’) were used in this study. It was determined that the peel and pulp of the ‘Kizil’ pear had the highest total phenolic content (402.5?mg/100?g and 215.2?mg/100?g, respectively), while those of the ‘Banda’ pear had the lowest total phenolic content (326?mg/100?g and 126.1?mg/100?g, respectively). Additionally, the ‘Kizil’ pear showed the highest antioxidant capacity in the 2,2’-azino-bis(3-ethylbenzothiazoline-6-6-sulphonic acid) (ABTS) and ferric-reducing ability assay (FRAP) (1.72 μmol TE/g FW and 161.25?μmol Fe II/g FW, respectively) and the highest ascorbic acid content (16.02?mg/100?g). The ‘Banda’ pear showed the highest antibacterial activity against the test bacteria. However, none of the pear extracts displayed antifungal activity. While all doses of the ‘Kizil’, ‘Gugum’, and ‘Banda’ pear extracts used in this study, except 80?μL/plate, exhibited antimutagenic activities, only the lowest dose (10?μL/plate) of the ‘Deveci’ pear extract showed the antimutagenic activity against induced mutagenesis in the Salmonella typhimurium TA 98 strain. Consequently, the five Turkish pear cultivars used in this study exhibited different levels of antimicrobial, antioxidant, and antimutagenic activities.     

Mechanische Fruchtbehangsregulierung verringerte den Junifruchtfall und verbesserte die Fruchtqualität und Fruchtgröße bei ‚Conference‘- und ‚Alexander Lucas‘-Birnen

In the absence of any chemicals approved for thinning pears but market demand for large particularly cv. ‘Conference’ fruit, the objective of the present study as part of a MSC thesis was to improve fruit quality i.e. achieve these fruit sizes by mechanical blossom thinning. Therefore, 18-year-old cv. ‘Conference’ pear trees, trained as super spindles, on quince A rootstock with a spacing of 4?×?0.4 m were used in Klein-Altendorf near Bonn, Germany; cv. ‘A. Lucas’ and un-thinned trees served as control. These pear trees with intense flowering were blossom-thinned on 15 April 2009 with rotor speeds of either 300 rpm or 400 rpm both at 5 km/h tractor speed with the new mechanical thinning device developed at the University of Bonn in 2004–2006. Therein, a vertical mast supports three horizontal rotors, whose vertically rotating tines remove excessive flowers; the device is mounted on the front three point hitch of the tractor. In 2009, a year with severe June drop, mechanical thinning reduced the intensity of the natural June drop with increasing rotor speed and was stronger reduced in cv. ‘A. Lucas’ (by ?38%) than in cv. ‘Conference’ (by ?27% relative to the control). In cv. ‘A. Lucas’, the natural June drop was as strong as mechanical thinning and resulted in large-sized 80 mm pear fruit in the control; mechanical thinning with 400 rpm further increased fruit mass by 16 g relative to the un-thinned control or 6 g larger than in the thinning with 300 rpm. In cv. ‘Conference’, fruit fell within the next larger fruit size class after the stronger mechanical thinning with 400 rpm at 5 km/h: the portion of pear fruit in the 75/80 mm size class was 2 fold and in the 80/85 mm size class was 6 fold that in the control. The portion of <?60, 60/65 mm and 65/70 mm fruit was halved relative to the control; the average fruit mass was increased by 40 g. Vegetative growth appeared unaffected by mechanical thinning. The risk of both over-sized fruit and over-thinning appears small, since mechanical thinning reduced the natural June drop and did not induce subsequent fruit drop. Mechanical thinning was more efficient in cv. ‘Conference’, as intended, despite more intense flowering in cv. ‘A Lucas’. An economic evaluation proved difficult, since the natural June drop particularly in cv. ‘A. Lucas’ led to large-sized fruit (80 mm) in the control, and any (mechanical) thinning is associated with lower yields (?26% in cv. ‘Conference’ and ?12% in cv. ‘A. Lucas’). Overall, the results indicate the potential of mechanical thinning as a substitute (or combination partner for chemical thinning if approved) in pear.     

Study of Genetic Diversity of Pear Genotypes and Cultivars (<Emphasis Type="Italic">Pyrus communis</Emphasis> L.) Using Inter<Emphasis Type="Italic">-</Emphasis>Simple Sequence Repeat Markers (ISSR)

ISSR molecular marker was used to investigate genetic diversity of ‘Dare Gazi’ genotypes of Mashhad Esteghlal orchard and its relationship with other commercial and native cultivars of pear. Among ‘Dare Gazi’ genotypes of Mashhad Esteghlal orchard 23 genotypes were selected base on difference in tree vigor, leaf color, shape and color of fruit and also 33 other commercial and native pear cultivars from Esteghlal orchard and other Mashhad commercial orchards were studied. A total number of 230 DNA fragments were obtained using 11 primers of which 225 were polymorphic. On average, each primer produced 20.9 bands. Dice similarity coefficient ranged from 0.27 (between ‘Dom Kaj’ and Asian pear) to 1 (between ‘Dare Gazi’ 1 and 2 genotypes). Sample cluster dendrogram indicated that 56 genotypes were divided into 12 distinct clusters. The dendogram generated on the principle of Unweight Pair Wise Method using Arithmetic Average (UPGMA) was constructed by Dice coefficient and the genotypes were grouped into 12 clusters. ‘Dare Gazi’ genotypes did not show 100% similarity due to seed propagation or mutation, as ‘Dare Gazi’ 3 and 18 genotypes had the lowest similarity coefficient (0.64). Asian pears were placed in a separate group from European pears. And ‘Dare Gazi’ genotypes from different orchards were grouped separately, but all of them are called as ‘Dare Gazi’ pear for convenience. ISSR molecular marker can well identify the genetic variability among genotypes and cultivars and found suitable for grouping them.     

Nährstoffaufnahme von Obstbäumen im 1. und 2. Standjahr

The nutrient uptake of fruit trees in the first and second year of cultivation was analyzed. The following fruit species and fruit varieties were examined: sour cherry (‘Schattenmorelle, Rheinland’, Hüttners Hochzucht 170?×?53, one year old tree), pear (‘Conference’, Quince A, two year old tree), apple on M 9 inoculated with the varieties ‘Pinova’ (two year old tree with one year old crown, two year old tree), ‘Elstar’ (one year old tree, two year old tree with one year old crown, two year old tree), ‘Jonagold’ (one year old tree, two year old tree with one year old crown, two year old tree) und Süßkirsche (‘Regina’, Gisela 5, two year old tree).

1. There was low nutrient uptake in the first and second year of cultivation.
2. In the second year of cultivation the nutrient uptake of all fruit species was clearly higher than in the first year of cultivation.
3. In average of the proved fruit varieties the nutrient uptake in the first year of cultivation was: 8?kg N/ha, 2?kg P/ha, 6?kg K/ha, 1?kg Mg/ha and 9?kg Ca/ha.
4. In average of the proved fruit varieties the nutrient uptake in the second year of cultivation was: 3?kg P/ha, 9?kg K/ha, 3?kg Mg/ha and 26?kg Ca/ha.
5. Especially in the first year of cultivation the trees of the stone fruits showed a higher nutrient uptake per tree than the trees of the pome fruits. But related to the nutrient uptake per hectar this difference reversed or became infinitely small.
6. The nutrient uptake of both the three apple varieties and the different plant materials showed only low differences.

     

Vom Luxusgut der Kapitalisten zum Exportschlager – Erdbeeranbau, Vermarktung und Züchtung in China als drittgrößter Erdbeerproduzent weltweit

The 23% consolidation of China's strawberry industry from 70,000?ha in 2005 to 53,000?ha in 2006 due to extreme climate conditions reduced production from 840,000?t to 650,000?t. This tonnage includes a 40% market share for processing for the home market (150,000– 190,000?t) and frozen fruit for both the home market and export (70,000–90,000?t) and makes China the world's third largest strawberry producer after the US and Europe. Strawberry cultivation in China is characterised by family smallholders with an averaged acreage of ca. 2,000?m² and salaries of 2?euros/person/day for hired labour resulting in ca. 500?euros/1,000?m² gross return. The major growing regions are the provinces Hebei (near Baoding), Shandong, Liaoning with an acreage of ca. 10,000?ha each. Strawberry plants and varieties are imported, but new Chinese varieties such as ‘Chun Xing’, ‘Xing Du 1 and 2’, ‘Xuemi’ and ‘Chun Xu’ are increasingly grown. The Chinese varieties are characterised by their sweet flavour with low acidity, a pre-requisite for the Asian market, and good taste and are adapted to the respective growing climate. A portion of the strawberry harvest is used for processing due to insufficient external fruit quality such as size, shape and colour by European standard. Strawberry research in China is spread between 9 institutions and universities throughout the country. Strawberries were regarded as exclusive desert and luxury for the upper class during the ten years of the cultural revolution between 1966–1976 under Mao Zedong. Today, fresh strawberries are sold in street markets or supermarkets. Import of strawberry fruit is prohibited, except for Hongkong, which imports 2,200?t from China and the US. China's export of 76,000?t in 2005, equivalent to a 9–10% export rate, was shipped to Japan (11,000?t) and Germany (8,700?t) with dumping prices below 50?cent/kg.