Vol. 15 No. 1-2 (2009)

Published March 25, 2009

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  • Resistance Gene Analogs (RGA) as a tool in fruit tree's breeding
    7-15.
    Views:
    169

    Breeding for pest and disease resistance comes as a major objective behind the fruit traits. To increase the effectiveness of fruit resistance breeding application of the Marker Assisted Selection ( MAS) is advantageous. For generating molecular markers which enable the following of interesting traits basically two methods are available: targeted marker design based on conservative region of already known Resistance ( R) gene sequences or randomly generated markers. The creation  and the application  of  these homology  based  markers  are the object of this review in  the main  temperate zone  fruit species.

    180
  • Specialities of the vegetation start and level of primary fruit set affect fruit quality
    17-22.
    Views:
    159

    Thinning is a h ighly crucial point of the apple production technology. According to results of numerous studies the earliest thinning is deemed to have the best amending effects. There can be considerable difference between trees of the same cul tivar and age in a plantation in respect to their flowering, in the numbers of fruits set and also in their canopy volume. Thus it can be crucial -just l ike in the case of pruning- to establish a fruit thinni ng su i ted for specif ic characteristics of actual trees. This experiment was established to examine how does primary fruit set (fruit load before thinning) and further on specific (fruit/TCS cm2) and absolute (fruit/tree) fruit-load of the trees affect quality attri butes at harvest. Our experiment was establ ished in a plantation on medium-tight loamy soil in north-east of Hungary. Harvest date was determined w ith the joint observation of the calendar date, starch-index, flesh firmness, background colour and fruit weight. Three fruit-load levels were established based on local experience and on data of several years, I Ot/ha lower and higher besides the advised optimum yield in the same orchard with slender-spindle shaped 'Gala must' cultivar standing on M9 rootstock in 1m x 3,8 m spacing. In the establishment of the 15, 25 and 35t/ha fruit-load levels on 20-20 apple trees total number of fruits set was counted at each tree. After this number of apples due to be removed was defined using an objective index on the basis of trunk cross sections (fruit/TCScm2) (Lafer, 1999). The following attributes were measured: weight (g), flesh firmness (lb/cm2) total soluble solid content (Brix %) and total titrate-able acid content (g/J).From the data on sugar and acid content quality index (Pomona value) was determined (Thialult, 1970). We could ascertain, that in an orchard, of the same aged but in concern to trunk cross sections somewhat different trees besides the specific index (apple/TCS cm2 the absolute fruit load (fruit/tree) can also be an important data, that has considerable effect on the internal quality. Secondly we could observe, that higher level of fruit load before thinning (primary fruit set) negatively affects quality index of the apples irrespective of the specific fruit load level (fruit/cm2 TCS) set later. Results underlines necessity of the earliest chemical thinn ing.

    163
  • Floral analysis can be use as an early plant analytical tool to diagnose nutritional status of fruit trees?
    23-27.
    Views:
    186

    A field experiment was conducted in an integrated apple orchard (Malus domestica Borkh.) established on a lowland chernozem soil in East-Hungary, to investigate if flower analysis could be used to diagnose the nutritional status of the trees. In April 2008, during full bloom, flowers and leaves were collected. Leaves were collected again in August, at the standard sampling time from the same trees. The content of nitrogen, phosphorous, potassium, calcium magnesium and boron were measured in flowers and in leaves. Correlation analyses were carried out to establish the relation s between nutrient contents in same and different plant part s. In flowers the following ratio was found between nutrients: N:P: K:Ca:Mg:B -10: l.35:7: 1.7: I :0,02. From result s it was evident that flower as organ contain significant and comparable amount of nutrients like as leaf. The N, K and Ca content were higher in leaves than in flowers at full bloom. The opposite was true for B. The P and Mg content of flower were quite equal with leaf P and Mg at full bloom . All examined nutrients were significantly affected by cultivars both in flowers and leaves. Significant correlation, was found between flower P and leaf P, flower B and leaf B (P=O.O 1) and flower K and leaf K at blooming time (P=0.05). Significant, but weaker correlation was also found between flower K and leaf K and between flower Mg and leaf Mg al JOO days after full bloom (P=0.05). Moreover, strong, but negative correlation was observed between flower B and leaf B at 100 clays after full bloom (P=O.O 1). Within flowers, the strongest positive correlation was found between Mg and B content (P=O.O 1). Strong positive correlations were also recognised between flower K and flower N, Ca and Mg and between N and Ca in the flowers (P=0.01). The strongest correlation was found between K and P in leaves at full bloom (P=O.O 1 ). Strong significant correlation was observed between N and B in the leaves collected at standard sampling time (100 DAFB) (P=0.01). Strong, but negative correlations were found bet ween leaf Mg and leaf P, K and between leaf N and leaf P at 100 days after full bloom (P=O.O 1).

    185
  • Studies on the drought responses of apple trees (Malus domestica Borkh.) grafted on different rootstocks
    29-36.
    Views:
    353

    The morphological and chemical changes in the leaves of eight apple varieties grafted on M4, M26 and MM 106 rootstocks were examined during fruit development in non-irrigated plantation. The aim of the experiment was to examine the defensive mechanisms in apple trees under the mild and serious dryness occurring during fruit development. The content of a relative chlorophyll (SPA D value) of the apple leaves on eastern side of the trees was lower than western and southern sides under drought occurring du ring fruit devclop111ent Under sustained drought from first of July to August the SPAD value, the weight of leaves were larger and the stomata density was significantly larger than in the previous periods. There was a close positive significant correlations bet ween SPAD and stoma density both in the group with less sensitive to drought (r=0,8429) and in the large water demanded group (r=0,9209) equally. The rate of increase in SPAD values and the stoma density was slower in the group with drought tolerant, than in the group required good water supply. The varieties being sensitive to water deficite such as Akane. Pink Lady and Red Rome van Well have a l ready responded intensively to short time of drought by the increasing of carbohydrate and antioxidants product ions. At 42 days of sustained drought as soon as the level of carbohydrate in the leaves decreased, the antioxidant s contents of the leaves rised suddenly in the apple varieties with moderate water requirement s as Greensleeves and ldared. Gala apple variety seemed to be able to defend the drought for longer time because there was no change in relatively high level of carbohydrates and antioxidants of their leaves under severe drought during fruit development.

    238
  • Consumer preference for apples: the role of attributes influencing the choice and consumption
    37-43.
    Views:
    254

    Consumers consider good quality fruits to be those that look good, are firm and offer good flavour and nutritive value. Nowadays, consumers are, however, increasingly  interested  in food qualities which  cannot  be discovered  by  looking, tasting or smelling  the products but their roles are not yet really cleared up. Therefore the objective of this study was to explore the importance of selected kinds of attributes (taste, size, colour, cultivar, origin and price) in fluencing the choice of apples of customers. In accordance with several authors, fruit qualities (taste, size and colour) seemed to be the major attributics influencing the choice of apple independently of people's age and gender. However, the size of fruit had lower importance with increased age. Generally, females gave higher importance rating for most attributes than did male. The price was getting more important for consumer's choice with age which can be connected with their socioeconomic situation. The origin of fruit and the cultivar did not have important influence on consumer's choice. Authors also investigated the preference of consumers for six selected apple varieties ('Jonagold', 'ldared', 'Royal Gala', 'Golden Reinders', 'Braeburn' and 'Granny Smith'). and pointed out the role of the origin in fruit quality and in choice of apple in the case of 'Granny Smith' cultivar. Apple fruit samples from Austria, Argentina, Chile, Hungary and South Africa were involved in this study. Authors evaluated fruit quality parameters of above cultivars and compared them to consumer preference. Consumer preference usually represented the quality attributes of the fruit well. It is also concluded that degree of liking of apple cultivars varies through gender and age. Children and young consumers preferred 'Royal Gala', 'Granny Smith  and 'Braeburn' mostly. In spite of 'Idared' is one of the cultivars grown on the largest area in Hungary, the lowest preference ratings were given for it in both gender categories. Middle-aged consumers (between 25 and 50 years or age) preferred crispy apples with red or blemished skin color ('Royal Gala' and 'Jonagold'). 'Jonagold' and 'Idared' were the most preferred cultivars for the consumers above the age of 50 likely because of their relatively low price, as price plays a significant influencing role in the purchase of these consumers. The relatively expensive and soury 'Granny Smith' appeared not really preferred by this age group. In spite of the significant differences in instrumentally measured fruit quality parameters among 'Granny Smith' fruit samples from different countries, consumers did not give significantly different preference rating scores for those.

    228
  • Apple powdery mildew caused by Podosphaera leucotricha: some important features of biology and epidemiology
    45-51.
    Views:
    320

    In this review, some important features of biology and epidemiology are summarised for apple powdery mildew (Podosphaera leucotricha). In the first part of the review, the geographical distribution or the pathogen are discussed, then the morphology and taxonomy of the causal organism are described. Disease symptoms or apple powdery mildew are also shown and then host susceptibility/resistance is discussed in relation to durability of resistance. In the second part of this review, the general disease cycle of powdery mildew on apple are demonstrated and some basic features of powdery mildew epidemiology (such response of the pathogen to temperature, relative humidity, and rain as well as spore production, spore dispersal, diurnal patterns and temporal dynamics of the pathogen/disease) are also given on apple host.

    269
  • Fire blight (Erwinia amylovora) resistance in apple varieties associated with molecular markers
    53-57.
    Views:
    219

    The invasive bacterial disease fire blight, caused by Erwinia amylovora has the potential to destroy fruit tree orchards all over Europe. Effective plant protection methods are lacking in many countries, highlighting the increasing importance placed on identification of germplasm with heritable disease resistance. Recent l y. a promising QTL (quantitative trait locus) was identified on linkage group 7 in the apple cultivar 'Fiesta· which is derived from ·cox's Orange Pippin' . I n the present study, 144 Swedish and foreign apple cultivars were analysed with the SCAR markers AE I 0-375 and GE-8019. which flank-. this QTL. Twenty-nine of the analysed cultivars had both markers. 78 had either AE I 0-375 or GE-8019, and 37 cultivars did not carry an) of the two markers. Seventeen cultivars. 7 with both markers and I 0 not having either of the two markers, were then inocoluted with the bacterium in a 4uaran1i ne greenhouse test. Cultivars carrying both DNA markers were significantly less susceptible than cultivars lacking the markers, P<0.001. Cultivars that were most resistant had both markers and had 'Cox· in their pedigree. Unrelated cultivars with the markers may still lack the QTL.

    224
  • Relationship beetwen the phenological features of pear cultivars and the main meteorological parameters in a gene bank with 555 pear
    59-63.
    Views:
    167

    The trees observed are grown at Ujfehert6, Eastern Hungary in a gene bank with 555 pear cultivars. Each of the cultivars was monitored for its dates of: the beginning of bloom, main bloom and the end of bloom and ripe phenophasis separately between I 984 and 2002. We analyzed the statistical features, frequency, distribution of these phenophasis and its' correlation the meteorological variables bet ween the interval. During this period the meteorological database recorded the following variables: daily mean temperature (°C), daily maximum temperature (0C), daily mini m um temperature (0C), daily precipitation (mm), daily hours of bright sunshine, daily means or the differences between the day-time and night-time temperatures (0C). For the analysis of data the cultivars have been grouped according to dates of maturity, blooming period as well as types of the seasons. Groups of maturity dates: summer ripe, autumnal ripening, winter ripe cultivars. Groups of blooming dates: early blooming, intermediate blooming, late blooming cultivars. At all the separated groups we analyzed the relationship between phenophasis and meteorological variables. During the 18 years of observation , the early blooming cultivars started blooming on 10-21 April, those of intermediate bloom date started flowering bet ween 20 April and 3 May, whereas the late blooming group started on 2- 10 May. Among the meteorological variables of the former autumn and winter periods, the winter maxima were the most active factor influencing the start dates of bloom in the subsequent spring. For the research of fruit growing-weather relationships we used simple, well known statistical methods, correlation and regression analysis. We used the SPSS 1 1.0 software for the linear regression fitting and for calculation of dispersions as well. The 1ables made by Excel programme.

    168
  • Irrigation of pear (A review)
    65-73.
    Views:
    166

    The plantation of intensive growing orchards and steady increase in yield is essential to return the growing cost by sale. Seasonal crop fluctuation of pear is increased by the frequently occurrence of drought and climatic changes. This study reviews genetic and growing factors determined the alternancy of pear and present the new knowledge concerning on water saving irrigation techniques. Use of dwarfing rootstocks, root pruning, branches pruning and new water saving irrigation make the changes in vegetative and generative growth that successfully improve the alternancy of pear growing. According to publications BA 29 of clonal quince rootstocks exhibited the best protection mechanism against to drought. Regulated deficit irrigation (RDI) applied during rapid shoot growth and slowly fruit growth result a decrease in shoot growth and 60% of water saving in pear orchard while there was no influence on harvested yield. Partial rootzone drying (PRD) microjet irrigation applied in pear orchard result 23-52% of decrease in water use, however concerning explorations are contradictory. Further investigations need to improve the efficiency of new irrigation technology adapted pear varieties based on monitoring of soil water status and measurement of stem water potential as stress indicators of plants.

    181
  • Seasonality of weather and phenology of reproductive organs of flower of sour cherry cultivars in Hungarian climatic conditions
    75-80.
    Views:
    186

    Sour cherry (Prunus cerasus L.) is one of the most important fruit crop grown in Hungary, The flowering phenology and pollen shedding/stigma viability ratio, in an effort to elucidate the reproductive phenology of nine economically important sour cherry cultivars (Érdi bőtermő, Debreceni bőtermő, Csengődi, Kántorjánosi 3. Pándy 279. Úfehértói fürtös, Petri, Éva, and Oblacsinszka) all widespread in the Hungary, was studied at Újfehertó climatic condition. The main aims were to investigate how possible environmental cues influence timing and development of phenophases and whether different cultivars have different seasonal responses to these cues. Likely effects of climatic changes on phenological development patterns were also considered. Our results revealed important aspects of the reproductive biology of sour cherry flowers. The amplitude of the phenophase "beginning of blossoming" between cultivars did not exceed 6 days. There is maximum 3 days difference in blooming length of different direction in each cultivar. Pándy 279 showed high variability when the position of flowers changed on the tree shoots. Újfehértói fürtös was stable in all four directions of tree. The pollen shedding period and stigma viability ratio was well synchronous. Pollen shedding phenomenon occurred in the range limitation of secretary activity of stigmas in all five cultivars. Distribution of pollen shedding over the secretary activity of stigmas is almost good. In all five cultivars maximum pollen shedding occurred about the high temperature part of the day.

    176
  • Response of sour cherry cultivar `Érdi jubileum' fruits to modified atmosphere packaging after ethephon spraying
    81-85.
    Views:
    164

    Sour cherries are not adapted to long storage. The largest percentage of sour cherries reaches the consumer either directly or indirectly through the tin can or the frozen pack. Different concentrations of ethephon usually are used commercially to facilitate harvesting sour cherry fruits that this hormone influences on fruit quality. The objective of this study was effect of ethephon preharvest application on sour cherry fruits quality during storage period at modified atmosphere packaging was investigated. Modified atmosphere packaging used with 10, 15 and 75 percent for 02, CO, and N2 respectively that those held at 0 °C. This gas compounds synchronous to 0 °C temperature caused to increase shelf life postharvest of fruits. Fruit samples were evaluated at harvest date and after 6 weeks in storage. Skin fruit colour, pH, total soluble solids, titrateable acidity, sugar/acid ratio, firmness were monitored. Ethephon concentration influenced on total soluble solid, titrateable acidity, sugar/acid ratio and L* value. In more case, 225 ppm ethephon's concentration has no observable different to control samples. Thus, the best ethephon's concentration was 225 ppm ethephon's concentration.

    192
  • First results of varios sour cherry cultivar on Oblacsinska as interstocks and Prunus mahaleb rootstocks
    87-90.
    Views:
    228

    At the experiment orchard of the Fruit Research and Extension Institute, Újfehértó, Hungary in spring 2000 a trial was designed included: Erdi bőtermő, Debreceni bőtermő, and Csengődi sour cherry (Prunus avium L) cultivars which were budded at 1999 on Oblacsinska sour cherry (as a dwarf inter stock), which had been budded on Prunus mahaleb seedlings at 1998 with the aim to investigate the dwarfing effects of Oblacsinska sour cherry cultivars on scion cultivars. Trees of each cultivar directly on Prunus mahaleb seedling, severd as controls. Use of Oblacsinska as an interstock reduced the rootstock trunk diameter. Trees of Debreceni bőtermő, and Cseng6di sour cherry cultivars with Oblacsinska interstock were smaller than similar trees grafted directly onto Prunus mahaleb as a rootstock. Trees of Erdi bőtermő grafted on Oblacsinska interstock which buded on Prunus mahaleb were the smallest. Growth of the trees was reduced also by using of the Oblacsinszka as interstock for other examined cultivars.

    174
  • Some biological features of cherry leaf spot (Blumeriella jaapii) with special reference to cultivar susceptibility
    91-93.
    Views:
    516

    In this review, some important features of biology are summarised for cherry leaf spot (Blumeriella jaapii). In the first part of the review, the geographical distribution of the pathogen and the causal organism are described. Disease symptoms and disease cycle of cherry leaf spot are also shown. Special attention is given to hosts and then several cherry cultivars.are described in relation to their susceptibility to cherry leaf spot.

    418
  • Factors affecting apricot fruit antioxidant capacity and mineral element contents
    95-99.
    Views:
    197

    Several epidemiological studies revealed that the consumption of antioxidant compounds and the risk of atherosclerosis, increased blood pressure or cancer are inversely proportional. The individual amounts and relative proportions of macro- and micro elements present in food is also of great consideration since these are involved in a wide range of physiological processes including the influence of the redox homeostasis. The antioxidant power and mineral nutrient content of fruits might be affected by several factors including genotype, ripening stage, year-effects or a wide range of environmental conditions. This study was carried out to survey the antioxidant power and mineral element content in fresh fruits of apricot and analyse some genetic and environmental factors that may have important contribution to the inner content of apricot fruits. In addition, the influencing effect of the extraction procedure used for antioxidant analyses was also tested. Our analyses indicate that a considerable fraction of antioxidant capacity is attributable to the hydrophilic antioxidants. The genetic background has crucial importance in determining apricot fruit antioxidant capacity and mineral nutrient content; however, the growing season and the ripening time of fruits may have also important effects.

    183
  • Optimization of RNA isolation from stone fruits at different ripening stages
    101-104.
    Views:
    181

    This study was conducted to select the most appropriate RNA isolation method that can be used successfully in case of stone fruits. The changing pattern of gene expression during the ripening process of stone fruits may elucidate the molecular background of several phenotypical or phytochemical alterations present among different genotypes. Our laboratory aims to study the expression of genes encoding for enzymes that catalyze crucial steps in the flavonoid biosynthesis pathway. RNA isolation from fruit mesocarp is a challanging task due to high levels of sugars and polyphenolics accumulating during fruit development. Therefore, at first, the optimal techniques eligible for RNA isolation from fruit tissues at different ripening stages must be selected. Our study compares three different RNA isolation protocols and describes their potential applicability according to different fruit species and ripening stages.

    190
  • Ripening related processes in strawberry, a nonclimacteric fruit: a short overview
    105-109.
    Views:
    180

    Fruits are essential part of the human diet: they provide vitamins, minerals, antioxidants to the mankind. Physiologically they can be divided into two groups-climacteric and nonclimacteric - depending if they display any respiratory peak and dramatic increase in ethylene biosynthesis or do not. Ethylene is a gaseous hormone playing a very important role in several physiological processes in plants. While climacteric fruits, like apples, bananas, tomatoes, peaches, apricots show increased ethylene biosynthesis and dramatic respiratory peak during their ripening, nonclimacteric fruits, like strawberries, grapes, citrus do not.

    The most widely used fruits for studying nonclimacteric ripening are strawberries: several papers are focusing on the identification and characterization of ripening related genes from this plant. Therefore here we attempt to summarize the most important advances in strawberry fruit development, and ripening.

    186
  • The effect of climatic anomalies on the nutrient supply of fruit plantations (Minireview)
    111-116.
    Views:
    215

    Climatic conditions play an important role in agricultural production. It has a profound influence on the growth, development and yields of a crop, incidence of pests and diseases, water needs and fertilizer requirements in terms of differences in nutrient mobilization due to water stresses. Nowadays, we have to know the dark side of the weather events because it is causing more and more problems and significant hazards to many horticultural regions in Hungary. The aim of this study is to explore the problems of nutrient uptake following climatic anomalies and response. These problems are: (i) water supply problems (water-stress); (ii) drought and frost as temperature­ strees. Reviewing the effects and nutrient disorders caused by climatic anomalies, the following statements can be taken:

    • Nutrient demand of trees can be supplied only under even worse conditions.
    • The most effective weapon against damage of climatic anomalies is preventative action.
    • When developing a fruit orchard, three factors should be taken into consideration: "Location, Location, Location".
    • Moreover, proper choice of cultivars, species and cultivation should provide further possibilities to avoid and moderate the effects of climatic anomalies.
    • Fruit growing technologies especially nutrition should be corrected and adjusted to the climatic events as modifier factors.
    • Urgent task of the near future is to correct and adjust the tested technologies of fruit growing according to these climatic events as modifier factors.

    Optimal nutrient supply of trees decreases the sensitivity for unexpected climatic events. To solve these problems supplementary, foliar fertilization is recommended, which adjusted to phonological phases of trees.

    Another solving is groundcover of soil means a potential opportunity to temper or even avoid climatic anomalies.

    172
  • The role of insurance in the damager mitigation of fruit orchards
    117-122.
    Views:
    148

    Hungary faced many natural disasters in 2007. Due to the estimation of the Hungarian Chamber of Agriculture, the amount of natural disasters that occurred in Spring 2007 (frost, hailstorm and drought in April and May) is about 100 billion HUF. Frost and drought caused damage on about 250 thousand hectares of arable land. Currently, there are four insurance companies dealing with agricultural insurances in Hungary. Their income was nearly 20 billion HUF in 2003, whereas it barely exceeded 6.6 billion HUF in 2004. The reason behind the significant decrease of insurance fee is the state provision made in 2004 stopping fee subsidisation which originally started in 1996, enabling farmers to require a 25-30% reimbursement of the amount paid for insurance. Launching a state subsidisation again would greatly increase the number of agricultural insurances. The law about the national agricultural mitigation system passed last Autumn. This provision declares that the mitigation of agricultural damage that cannot be insured on a business-like basis is based on the common risk-taking by the state and the farmers. The introduction of this system is explained by the fact that the mitigation of damages through disaster can only be carried out if those affected also take part in it, according to EU rules.

    182
  • Evaluation of a simple fruit tree structural model
    123-126.
    Views:
    152

    A simple three element tree structure model of Lang, 2006 was tested in plum orchard using two different inertia fruit tree shakers. The first was a slider crank type one; the second had rotating eccentric weights. The parameters of both were chosen to give similar frequency and amplitude output in average orchard conditions. Orchard experiments were carried out shaking the trees with both machines at several frequencies and shaking heights. The measured acceleration and amplitude values were plotted on diagrams together with the calculated acceleration and amplitude curves of the fruit tree-shaker machine model. Choosing the right fruit tree parameters, such as apparent spring constant, damping coefficient, reduced trunk mass and coefficient of elasticity of the trunk the measured and calculated values coincided well. This proves the ability of the fruit tree model for optimising the shaker parameters to any given orchard.

    188