Published September 19, 2007
The knowledge of blooming, pollination and fertilisation and its use are indispensable in maximizing of cropping potential of fruits in economical fruit production. In attaining maximum yield a greater attention has to be focused on choosing cultivar combinations, and results of experiments on blooming, pollination and fertilisation must be applie...d carefully. To have efficient bee pollination requires attention at the time of designing an orchard. It requires further attention at the time of bloom of any of the fruit-hearing species. Markets demand new types of fruit which forces constant changes in the cultivar composition of orchard. The blooming, pollinating and fertilisation characteristics of cultivars chosen have to be known before an orchard is set up. Apart from the general knowledge of trees considered to be planted, there is a great need to know the flowering, pollinating and fertilization characteristics of each cultivar in detail.
The basic conditions of fruit set (synchronic bloom, transfer of pollen, etc.) still do decide definitely the fate of the flower (Cano-Medrano & Darnell, 1998) in spite of the best weather conditions (Stösser, 2002). Beyond a set quantity of fruits, the tree is unable to bring up larger load. A system of autoregulation works in the background... and causes the drop of a fraction of fruits in spite of the accomplished fertilisation and the equality of physiological precedents (Soltész, 1997). There are also basically genetic agents in action. The further development of fruits maintained on the tree depends mainly on the growing conditions (e.g. water, supply of nutrients, weather adversities, pruning, fruit thinning, biotic damages, etc.), which may cause on their own turn fruit drop especially at the time of approaching maturity.
Genetic diversity in a collection of apple (Malus x domestica Borkh.) cultivars as revealed by RAPD markers
A collection of 151 apple cultivars was investigated with 7 RAPD primers generating 71 informative bands, to evaluate genetic variability and relatedness. All cultivars presumably derived through genetic recombination were distinguished whereas identical DNA profiles indicated that some cultivars had arisen as sports. A cluster analysis and a PCO ...did not reveal any distinct geographic patterns, but there was a weak tendency for Swedish and foreign cultivars to differentiate.. Many cultivars however clustered together with either one of their parents or with siblings. Overall genetic diversity among the 151 cultivars was estimated with Nei's diversity index (H), 0.269, and with Shannon's index (H'), 0.594. The cultivars were also analysed in six groups, according to time of origination and country of origin, with an average H = 0.262 and H' = 0.546. No major differences in genetic diversity were observed over time or space, although the group with recent, foreign cultivars had the lowest diversity (FL = 0.235, H' = 0.493). Comparison between the entire material and a subset with 94 mandate cultivars chosen for preservation in Sweden, showed similar genetic diversity: HFN.rj1E = 0.268, frE,NTIRE, = 0.593 and HMANDATE = 0.263, WMANDATE = 0.575. No major differences in band frequencies were observed between these two sets, but 5 RAPD bands were missing in the set with mandate cultivars.
Altogether 40, mainly old Hungarian apple varieties were screened with six previously described microsatellite markers. A total of 71 polymorphic alleles were detected (average 11.8 alleles/locus) and the heterozygosity of markers averaged very high (0.8). The genetic variability among the genotypes proved to be so remarkable that as few as three ...markers from the applied six were enough to distinguish between the 40 varieties. This was also confirmed by the cumulative probability of obtaining identical allele patterns for two randomly chosen apple genotypes for all loci, which value was quite low: 2.53 x 10-5. The molecular identification of these genetically very different old apple genotypes could be very useful in future breeding programs.
The elements of orchard management have a determining role in the success of organic fruit production, therefore, it is essential that they are applied properly. The present review gives describes some aspects of the orchard management such as site selection, orchard soil, rootstocks and cultivars, planting materials and plant density, crown shape.... Then, one of the most important elements, pruning is discussed with special emphasis on winter pruning, condition and apical dominance, degree and method of pruning, summer pruning. After pruning, an overview of fruit thinning, irrigation, soil cultivation, soil protection (cover plants and mulching) and fertilization is given.
Results on mating disruption by sex pheromones against moth pests of apple in integrated and organic orchards
The study was aimed to study that how mating disruption by hand applied dispensers can reduce the number of damage caused by Cydia pomonella, Adoxophyes orana and Pandemis heparana in four integrated and organic apple orchards. In the first orchard (Gacsály), protection against moth caterpillars ensured by IPM and conventional production systems ...were equally good, but worse than that of the orchard part where mating disruption was applied by 1000 dispensers/ha. In second orchard (Nyírbogdány), the highest incidence of codling moth damage was measured in the hilly part (17%), while in the plot where 440 dispensers/ha pheromone dosage was applied, the damage incidence was 11%. The smallest damage incidence was at the flat part, where 666 dispensers /ha was applied. In the third and fourth orchards (Eperjeske), codling moth damage on fruits was below 7% in the larger and smaller orchards where 1000 dispensers/ha was applied. At Eperjeske, the codling moth damage increased by 32.3% in the field treated with Bacillus thuringiensis product but without using mating disruption. The results verified that the use of 1000 dispensers/ha as suggested by the manufactures is essential, especially in the first year of application. The results also suggested that better results can be achieved in flat areas and the larger plot size also enables a more efficient reduction of the damage.
The aim of our two-year study was to evaluate fruit decay and Monilinia fruit rot in three controlled atmospheres (CA), ultra-low oxygen (ULO) and traditional storage methods on apples for a duration of several months storage period. Four phytopathological treatments were studied under each storage condition: 1) 48 healthy fruit per unit, 2) 48 in...jured fruit per unit, 3) 47 healthy fruit and 1 brown rotted fruit per unit, and 4) 47 injured fruit and 1 brown rotted fruit per unit. Our results clearly demonstrated that fruit loss during storage is highly influenced by storage conditions and health status of the stored fruits. In the 2005 experiment, the lowest and largest fruit decay occurred under the ULO and traditional storage conditions, respectively (Table 1). The fruit decay was significantly different for the different storage methods. Fruit decay was fully suppressed in ULO storage except in the treatments of injured and injured + 1 brown rotted apple. Under CA and traditional storage conditions, when healthy fruit was stored, fruit decay was significantly lower compared with injured fruit including 1 brown rotted fruits. However, half of the fruit decay was caused by M. fructigena in CA store irrespective to phytopathogenic treatments. In 2006, results were not so consistent on cv. Idared but were not essentially different from the 2005 experiments.
The saving of soil water content and the improvement of adaptability of plants to periodical insufficient water and use of deficit irrigation technology become more important because of the occurrence of frequently dry periods. The water use efficiency of apples can be increased by the choice of appropriate rootstocks and determination of water re...quirement of varieties that depend on their growing periods and climatic factors. Depletion of soil water resources need to develop efficient irrigation techniques for quality apple production. A new deficit irrigation strategy (PRD) has been developed that based on partial water supply of root-zone. This does not result a decrease in the sizes and yield of the fruit. The larger fruit size and lower firmness in frequently irrigated trees can result in excessive internal growth stresses that cause higher rate of fruit splitting. Many studies revealed the relationship between irrigation and yield quantity. Recent researches investigate the effects of irrigation on apple fruit quality particularly on the colouration and post-harvest quality. Use of cooling irrigation improves the development of coluour an apple fruit but its schedule can influence on the incomes. Aroma volatiles are responsible for odour and contribute to overall flavour of the fruit and its processed products. Deficit irrigation had only affects some volatile aroma but no the all of concentrations in apple fruit. In the future the high apple quality for consumers could be provided with improvement of transpiration-yield model based on the water requirement of varieties and economic irrigation schedules.
In this study I investigated the cost and profit conditions and the efficiency of intensive, qualitative apple production on the basis of a data collection carried out in ventures of high standard production. I concluded that the intensive apple production has an extremely high cost requirement, the production costs are approximately 1500 to 1600 ...thousand HUF per hectare. In an average case, a production value of 2000 thousand HUF per hectare may be reached, which may fluctuate in a wide interval during the years. Considering the above mentioned, a net profit of 400 to 500 thousand HUF may be realized in one hectare. It should be highlighted that regarding the present marketing conditions, realizing the appropriate profit may be expected only by producing 30 to 40 tons per hectare yields and 80 to 90% food quality ratio.
Severely pollen-limited fruit set in a pear (Pyrus communis) orchard revealed by yield assessments and DNA-based paternity assignment of seedlings
In commercial fruit tree orchards, consistently high yields are necessary for a durable economy. The Swedish pear cultivar 'Carola' has been noted for low setting in some orchards, possibly due to insufficient pollination. In this study, fruit set was evaluated in a research orchard where `Carola' had been planted together with four potential poll...inators. Total yield and number of fruits was noted during three and four years, respectively. In 2003, seeds were germinated from the harvested `Carola' fruits, and the paternity of three seedlings from 50 trees was determined with RAPD analysis. 'Clapp's Favourite' had sired 39.6% of the seedlings, closely followed by `Seigneur d'Esperen' (30.7%) and 'Clara Frijs' (26.7%) whereas 'Skanskt sockerparon' only sired 1.1% of the seedlings. The remaining 2.3% appeared to have been derived by selfing. Pollen-limited seed set was indicated at surprisingly short distances; accumulated number of fruits on the `Carola' trees was significantly higher when separated by only 2 m from one of the two most efficient pollinators, 'Clapp's Favourite' or 'Seigneur d'Esperen‘, compared to trees 4—l0 in away in the same row. Number of viable seeds per fruit was also higher in fruits from trees immediately adjacent to the pollinators, suggesting an effect of improved pollination success. The importance of very short inter-cultivar distances for efficient pollen transfer became even more clear when comparisons involved the true pollination distances as determined by RAPD; the accumulated yields decreased linearly from 55 kg at a 2 in distance to only 17 kg at 13 m.
In this study, the pollen of 14 sweet cherry cultivars (‘Anella’, ‘Duroni 3', 'Badacsony', 'Cristalina', 'Ferbolus', 'Ferrovia', 'Georgia', 'Hudson', 'Kordia', 'Sam', 'Schneiders’, ‘Spate’, ‘Knorpelkirsche', 'Skeena', 'Summit', 'Sylvia') was used to fertilize the emasculated flowers of sweet cherry cv. 'Regina'. Fruit set was assess...ed three times during fruit development: 14 May, 30 May and 27 May 2007. We observed full incompatibility among the 14 cultivars for cv. 'Cristalina', which is in the same S-allele group as cv. 'Regina'. After analysis of our data, we have results about fertilization efficiency of the cultivars. Most of the evaluated cultivars are inadequate to fertilize cv. 'Regina' to a sufficient degree. There were two exceptions, cv. 'Sam' and cv. 'Skeena', where percentage of ripened fruits was above 20%. These two cultivars can guarantee such a pollination, which ensures ample quantity of ripened fruits. Results of this study have proved three other cultivars to be quite good pollinators for cv. 'Regina'. In conclusion, ideal pollinators for cv. 'Regina' could be — apart from above-mentioned two cultivars, 'Sam' and 'Skeena' — cvs. 'Sylvia' and 'Bianca', which was suggested by more literature sources.
High density central leader systems, the so called "spindle trees" are spreading in intensive stone fruit orchards established for hand picking in Hungary. Results of Brunner (1972, 1990) and Zahn (1967, 1996) inspired the researchers to implement their theories into practice under our climate and special soil conditions. For sweet cherry it is es...sential to apply an orchard system appropriate for hand picking because of the European market requirements. In intensive sweet cherry orchards two new training and orchard systems are developed and adapted to environmental conditions in Hungary based on previous inventions. The first step of the development is represented by modified Brunner-spindle, which applies the delayed heading of the central leader and the sectorial-double-pruning system from Brunner (1972), resulting intensive orchard of 600-800 trees/ha density, planted on standard vigour rootstocks. Modified Brunner-spindle trees are developed with a central leader and wide-angled branches on it. Light bearing wood is positioned on the central leader and wide-angled branches. During training, shoots for branches are bent or a sectorial double pruning is used. The growth of central leader is reduced by delayed heading, and the strong upright shoots are pinched in summer. Based upon tree size spacing of 5 m between row and 2.5-3 m between trees is recommended, tree height is around 3.5-4 m. This training system is useful for hand-picking; 60-70% of the crop can be harvested from ground. Modified Brunner-spindle is suitable for either standard or moderate vigorous rootstocks. The cherry spindle is an intensive orchard planted with 1250-2300 trees per hectare and it is recommended for sweet and sour cherries on semi dwarf to vigorous rootstocks, depending on soil fertility and quality. Trees are 2.5-3.5 m high, 75-80% of the crop can be harvested from the ground. Permanent basal scaffolds are developed on the basis of the canopy to counteract the stronger terminal growth. The tree is headed only once, after planting, from the following year the central leader grows from the terminal bud. The central leader developed from the terminal bud results moderated growth in the upper parts of the tree head. The strong upright shoots that may develop below the terminal bud are pinched to 3-4 leaves in the summer or removed entirely. The weaker, almost horizontal shoots growing from the central leader form fruiting twigs in the following year if their terminal bud is not removed. Brunner's double pruning is used only once or twice on the permanent basal branches because of its good branching effect. Trials on various rootstocks are running to find optimum spacing and fruiting wood management. The training and pruning guidelines are discussed in the paper. The average crop of bearing years is around 20-30 t/ha depending on site and cultivars. This new system is spreading in Hungary, around 70 ha sweet and sour cherry orchards are trained according to our guidelines.
Effect of different flower thinning techniques on annual fluctuation of macro and micronutrients in sweet cherries
The seasonal dynamic of macro- and micronutrients uptake of a sweet cherry cultivar cv. 'Katalin' (Prunus avium L.) was studied according to apply different flower thinning techniques. Beside control treatment, three thinning treatments were performed: (I) thinning for I flower/inflorescence, (2) thinning for 2 flower/inflorescence, (3) thinning f...or 3 flower/inflorescence. Soil examination was carried out to establish the growing conditions of orchard site. Moreover, for studying the temporal dynamic of nutrient uptake plant analytical examination was performed four times per year based on leaf collecting according to the phenological phases. It was found that the macro- and micronutrients contents of leaves were showed significant differences between treatments before ripening, at ripening and after ripening stage. It was found that thinning has influence on mineral composition of leaf. Flower removal unbalanced the equilibrium of generative and vegetative processes. The applied manual flower thinning treatment resulted improving vegetative processes like nutrient uptake and storage.
Comparative study of effects of a complex fertilizer and a biostimulator on macroelement content of leaf and fruit quality on sweet cherry (Prunus avium)
In this study. we are partly focusing on consumer acceptance of fruit, like fruit cracking, weight and flavours, and maturation, fruit density and content of nutrients which are undelie consumer acceptance, and important equally to the growers and marketers. the results on the dynamics of N-uptake corresponded ti thephenological phases of cherry a...nd independent on the applied treatments. Younger leaves contain more N than elder due to the effective N uptake of young leaves. Based on the measurements conducted in June, the P content of leaves was in low P supply category at the control and the Benefit treatment, while was in the lower range of optimal category at Damisol treatment. According to our measurements, the K of cherry leaves decreases continuosly until September, expcept the control at which it increased from the end of June to September. the fruit weight was increased significantly by applying Benefit PZ. the best results for fruit cracing observed at Benefit treatment too. The best result for fruit density was observed at Damisol treatment.
Some biological properties of new sweet cherry cultivars in Bulgaria and their susceptibility to Blumeriella jaapii
Investigations were made on 12 sweet cherry cultivars (‘13-S-22-8’, 'Sunburst', `Kozerska'., 'NY 13791', 'Royalton', 'NY 13688', 'Hartland', `Sumerset', 'Pollax', 'Patriotka Krima', 'Castor', and `Lapins') in an experimental orchard of cherry cultivar collection in the Institute of Agriculture at Kyustendil, Bulgaria during the period of 1997-...2003. The trees were planted in 1996. All cultivars were grafted on Prunus mahaleb. Four biological properties of the cultivars were assessed such as blooming time, resistance to late spring frost, fruit ripening and fruit mass. Among cultivars, a good resistance to late spring frost was observed on cultivar 'Sunburst'. The fruit mass varied between 4.2 g (cv. 'Patriotka Krima') and 8.5 g (cv. `Sunburst'). The susceptibility of the cherry cultivars to cherry leaf spot caused by Blumeriella jaapii was assessed in mid-September in each year. The estimation of the rate of attack was made according to the grade of Townsend and Neuberger. All cultivars showed symptoms of cherry leaf spot but the degree of susceptibility was different. Cultivar `Patriotka Krima' was the least susceptible, while cultivar `Somerset' was the most susceptible to Blumeriella jaapii.
Determination of flower microphenology for selecting the suitable pollinizer for sour cherry cultivars is of significant importance. In order to study the flower microphenology of Hungarian sour cherry (Bőtermő, Érdi jubileum and Cigány) cultivars in Mashhad climatic conditions, an experiment was conducted in I998. 1999, 2005 and 2006, using a... completely randomized design with ten replications. The phenological stages were determined from before opening up to browning phase of stigma. Duration of pollen shedding, stigma receptivity and climatic factors were measured. The relative time of flowering between cultivars varied from year to year. The data indicate, the thermal variation strongly contributes to significant differences in duration of stigma viability, although there wasn't a significant difference between cultivars in anther dehiscence period. Phenological stages of flowers are highly affected by meteorological factors in various years.
Recently, the sour cherries as food resources become more important for health preservation and so the modernization of growing technology in sour cherry production will be timely. The global warming and inadequate distribution of precipitation result a decrease in the alternancy of sour cherry production, as well. Sour cherries rather adapted to ...survival of drought than sweet cherry trees therefore a few studies performed to explore the water requirement of sour cherry varieties. The rootstocks, the type of soils in plantation and the water balance influence the water management of sour cherries. In orchards, in particular first year plantation, use of various row covering contribute to preservation of the natural water pool of soil and affect on the tree vigor, yield and fruit quality. Wide-spread application of integrated fruit growing technology and climate changes the researches are pointed to develop efficient irrigation technology based on transpiration yield model. The crop model based on use of meteorological data was developed for cherry orchards in order to predict transpiration of trees, dry matter production and fruit yield. The linear relationship between dry matter accumulation and transpiration was verified for sour cherry trees. Other models essay to asses the effects of climate changes on crop production. Importance of economical production and fruit quality such as ingredients of raw materials and food increases in intensive sour cherry orchards used by irrigation techniques. Because of climate changes it should more pay attention to research concerning on the stress physiological response of sour cherry varieties and post-harvest fruit quality.
Cracking susceptibility of sour cherry (Prunus cerasus L.) in Hungary and relation to calcium application
The rain induced fruit cracking is a big, serious problem especially for sour cherry growers but in some year sour cherry growers had also problem with fruit cracking caused by too much rainfall in the harvesting season. The cracked sour cherry fruits can be easily infected by different diseases like Monillinia sp. Cracked and infected fruits can ...not be transported for long distance and using for preservation because they lost their market value by the pour fruit quality. There are two possibilities to protect fruits against the rain induced fruit cracking. The most effective protection technique is the plastic rain cover over the tree rows. The installation of these equipments is too expensive for the growers. That is the reason why researchers tried to find other less expensive and sufficiently effective ways like sprayings different mineral salts, hormone and other type chemicals against the rain induced fruit cracking. Several calcium formulas calcium chloride (CaC12), calcium hydroxide (Ca (OH),) and calcium nitrate (Ca(NO3)2) can be sprayed in appropriate solution concentration. The aim of our trial is to determinate the fruit cracking susceptibility of wide grown Hungarian sour cherry varieties and find the most effective calcium formula and its concentration for spraying in orchards to prevent the fruit cracking. In the first trial year (2006) cracking index of tested sour cherry varieties were determined under field and laboratory conditions. Under field conditions were not found differences between cracking tendency of tested cultivars. After results of immersing fruits in distillated water for 24 hours tested sour cherry varieties were divided to three groups by the susceptibility to rain induced fruit cracking: very susceptible (`Maliga emléke', 'Piramis', 'Érdi jubileum', 'Erdi nagygyümölcsű’ and 'Meteor korai'); susceptible ‘Érdi bőtermő, Tandy 279' and Cigány 59.; moderately susceptible/tolerant ("T" and "R" clones). In the second trial year (2007) calcium chloride (CaCl2) and calcium nitrate (Ca(NO3)2) were sprayed in 0,35m/m%; 0,5m/m% and 1,0m/m% solution concentration. One more commercial product "Damisol-Kalcium" was also applied in the advised 1,0m/m% concentration. Like in the trial year before (2006) under field conditions we did not kept differences between the cracking susceptibility of varieties and calcium treatments. As the result of laboratory testing (immersing calcium treated fruits in distillated water) we kept that calcium chloride (CaCl2) seems the most effective against the fruit cracking in 0,5m/in% solution concentration. The other calcium formulas also decreased the cracking ratio but in less scale.
Evaluation of sour cherry (Prunus cerasus L.) and European plum (Prunus domestica L.) varieties for making dried fruits
The aim of our drying trials was to determine the drying suitability of stone fruits. The tested species were sour and sweet cherries and European plums too. Data and results of sweet cherry drying were published earlier (Klincsek et. al. 2005, 2006).This article containing results of twenty sour cherry and six European plum varieties. Laboratory ...tests, drying processes and sensory testing were done at Fruit Quality Testing Laboratory of Fruit Science Department of Corvinus University of Budapest. The sensory tests and their valuations were done by the instruction of National Institute for Agricultural Quality Control. In the case of sour cherries by one year data in 2004 we divided fruits to five categories by suitability for making dried fruit. Varieties in the first two groups are the followings: most suggested for making dried, fruits: 'Meteor korai' and `Érdi jubileum'; suggested: 'IV-3-48' and `Piramis'.In the case of European plums three varieties can be suggested for making dried fruits from the six tested cultivars: ‘Révfülöpi’, Althann gage' and `Besztercei'.
In this review, we give an overview of recent cultivation systems in commercial plum orchards. The aspects of selecting the shape of the crown and the spacing of trees are discussed first and then growth characteristics and the structure of the crow are described in detail. Finally, the wound healing and regeneration characteritics of plum trees a...re detailed which have an influence on the applied pruning technique.
In this review, we give an overview of the pruning techniques that should be applied in commercial plum orchards. First, a detailed description of pruning for shaping the different crown types for the first, second, third, fourth and fifth years and the phytotechnical works is given for crowns with a circular projection area. Then, pruning for ope...n crowns forms, such as the vase form is discussed. Following the shaping of the crown, it should be maintained by pruning. Detailed information is given on pruning for maintenance with special emphasis on the comparison of winter and summer pruning. In the following part of the manuscript, pruning experience is described separately for the major commercial plum cultivars in Hungary such as Cacanska lepotica, President, Bluefre, Stanley. Recommendations for cultivation systems under non-irrigated conditions are also included. Finally, light requirements, growth characteristics and suggested crown forms of the different cultivars are described for cvs. Ageni, Althan Tingle), Besztercei szilva Nm. 122, Bluefre, Cacanska lepotica, Cacanska rodna, Debreceni muskotály, Montfort, President, Ruth Gerstetter, Sermina, Stanley, Tuleu gras and Zöld ringló).
The aim of our two-year study was to assess incidence of brown rot blossom blight and fruit rot caused by Monilinia laxa in 2003 and 2004. Assessments of incidence were made on cv. Bergeron (susceptible to brown rot) in a flatland and a hilly growing area (at Cegléd and Gönc, respectively). In both locations, plant protection was performed accor...ding to the integrated fruit production guidelines and small untreated plots were set up for each cultivar in both years. In 2003, when weather conditions were dry and hot, brown rot incidence was low (less than 10%) on both blossoms and fruits. Monilinia laxa did not cause significantly different blossom blight and fruit rot at the hilly (Gönc) area compared to the flatland, not even in untreated plots. However, in 2004, when spring and summer weather conditions were wet and cold, Incidence reached 95% for blossom blight and 33% for fruit rot in the untreated plots. Blossom blight incidence was 1.5-2 times higher in the flatland area compared to the hilly growing area. During the blooming period of apricot, two (at flower bud stage and at full bloom) and three (at flower bud stage, at full bloom and at petal fall) fungicide applications were necessary for the successful control at Gönc and Cegléd, respectively. The difference between the two orchards was due to the fact that blooming started one week later in the hilly region (at Gone) than in the flatland region (at Cegléd), therefore, the critical weather period coincided with blooming in the orchard in the hilly region only partially. Fruit rot incidence was similar in both regions as the amount and distribution of rainfall were similar during the fruit ripening period.
The aims of this study were on the one hand to compare of examined compounds according to their importance in nutrition and human-health, and on the other hand we made preexperiments to investigate the relationships among antioxidant capacity and the endogenous substances which contribute the antioxidant status of the plants. The following species... were involved in the experiment: raspberry, blackberry, black currant, elderberry and sour cherry. These fruits have potent health-promoting antioxidant power. Glucose, fructose, total phenol, formaldehyde and anthocyanin contents were determined in addition to ferric reducing ability. Our results reflected considerable differences in the measured parameters of the analysed species. In blackberries and elderberries the high antioxidant capacity is coupled with low carbohydrate content. Besides the formerly proven correlations between total phenol content, anthocyanin concentration and antioxidant capacity, these parameters also correlated with the measured formaldehyde concentrations, hereby we can follow the methylation /demethylation status of the plant.
Black locust (Robinia pseudoacacia L.) is the most important fast growing stand-forming tree species in Hungary. Its importance is increasing in many other countries, too. As a result of a new selection programme 13 black locust clones have been improved for setting up clones trials and seed orchard. In 2003 five of them (R.p. `Bácska', `Homoki',... 'Szálas', `Oszlopos' and `Vacsi') were registered as cultivarcandidates. Tissue culture method has proved as a suitable mean of propagating superior individuals. The micropropagated plants have been growing successfully in the clone trials.