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• Floral biological studies on pear cultivars in relation to fire blight susceptibility

  25-30.

  A. Farkas

  Zs. Orosz-Kovács

  T. Bubán

  Views:

  419

  Floral biological characteristics that may influence cultivar susceptibility to fire blight were studied in 10 pear cultivars in two Hungarian orchards from 1999 to 2003. The receptaculo-ovarial, automorphic nectary is usually bigger in tolerant cultivars than in susceptible ones. Nectary stomata are meso- or xeromorphic. Susceptible cultivars tend to have more xeromorphic stomata, where guard cells are located 1-3 cell rows below the epidermis. The size of nectar chambers is usually smaller in susceptible cultivars. Floral nectar, consisting mainly of glucose and fructose, is more abundant and less concentrated if the cultivar is susceptible to fire blight. The amount of chlorogenic acid was higher in the flowers of tolerant cultivars than in susceptible ones.

• A preliminary study on some features of two new resistant apple cultivars in a multi-row planting system

  11-14.

  Á. Csihon

  I. Gonda

  P. Vámos

  D. Barna

  I. J. Holb

  Views:

  918

  The aim of this work was to report preliminary results on some features of two new resistant apple cultivars (cvs. ‘Galiwa’ and ‘Story Inored’) in multi-row system in the early bearing years of the orchard. Trees were planted in spring of 2015 in double row design (3.5 m+1.4 m x 1.0 m) with planting density of 5357 tree/ha. According to our results cv. ‘Story Inored’ presented more vigorous growth, than cv. ‘Galiwa’. Trees of cv. ‘Story Inored’ reached 2.7 m in the third year, but cv. ‘Galiwa’ could reach only 1.95 meter. Due to late spring frost 100% yield loss was observed in the second year. In 2017 cv. ‘Galiwa’ produced 5.3 kg/tree (25 fruit/tree), while cv. ‘Story Inored’ presented 7.7 kg/tree (50 fruit/tree). Average yield was 28.4 t/ha for cv. ‘Galiwa’, as ‘Story Inored’ reached 41.3 t/ha in the third year. Cultivar ‘Galiwa’ reached the required fruit size (79.1 mm), but its coloration was weaker (43% fruit surface color). Cultivar ‘Story Inored’ can be described with smaller fruit size (69 mm) and higher percentage of surface color (93%).

• Vegetative and generative properties of two apple cultivars ‘Galiwa’ and ‘Story Inored’ in a multi-row system

  34-38.

  A. Csihon

  I. Gonda

  I. J. Holb

  Views:

  631

  In a five-year (2015-2019) study, some vegetative and generative peculiarities of two resistant apple cultivars (‘Galiwa’ and ‘Story Inored’) were assessed in a young orchard with a multi-row training system. Based on our research, cv. ‘Galiwa’ showed significantly weaker growth, than cv. ‘Story Inored’, which was manifested in lower trunk cross sectional area (TCSA) and lower tree height. Cultivar ‘Story Inored’ reached the optimal tree height (3.1 m) at the age of four, but cv. ‘Galiwa’ could not achieve it neither in five-year-old trees (2.7 m). Cultivar ‘Galiwa’ showed 28.4-32.6 t/ha calculated average yield, while cv. ‘Story Inored’ produced 41.3-102.7 t/ha. Larger fruit size was found in cv. ‘Galiwa’ (72.7-79.1 mm) and smaller in cv. ‘Story Inored’ (66.9-69.2 mm). The fruit surface color was under 50% for cv. ‘Galiwa’ (43-49%), meanwhile cv. ‘Story Inored’ reached higher coloration (87-93%) and an excellent color intensity (4.8-5.0). Shape of cv. ‘Galiwa’ fruits was rather flat, than globular (0.83-0.84 shape index), as cv. ‘Story Inored’ was more elongated (0.95-1.00 shape index).

• DNA-based determination of suitable pollinating cultivars for the pear cultivar 'Carola' (Pyrus communis)

  15-19.

  H. Nybom

  J. Sehic

  H. Mattisson

  Views:

  245

  Pollen-limited fruit set has long been suspected in some relatively low-yielding orchards with the Swedish pear cultivar 'Carola'. Fruit was therefore harvested on 23 'Carola' trees in a commercial pear orchard. The seeds were germinated and five seedlings from each tree were sampled to determine which of the surrounding cultivars had been the most successful pollinators. Leaves of 'Carola', the 7 putative pollinating cultivars and the 115 seedlings were analysed with 6 RAPD primers. By comparison of the band patterns, paternity could be ascertained for 74 seedlings. The by far most successful pollinator was 'Clara Frijs' which had sired approx. half of the seedlings, followed by 'Herzogin Elsa', `Skanskt Sockerpiiron', 'Alexandre Lucas', 'Coloree de Juillet' and 'Doyenne du Cornice'. The latter is the maternal parent of 'Carola', and these two cultivars must therefore share one S-allele and hence can only be semi-compatible. In addition, 6% of the seedlings were in all likelihood derived from selling_ since they showed no bands that did not occur also in 'Carola'. Maximum distance between 'Carola' trees and suitable pollinators should not exceed 15-20 tn. Longer distances may produce a serious dearth of compatible pol­len as evidenced by the large percentage of seedlings derived either from selling. (25%) or from long-distance (> 40 m) pollen transfer (25%) when 'Carola' trees were surrounded by non-preferred pollinators.

• The role of black locust (Robinia pseudoacacia L.) in establishment of short-rotation energy plantations in Hungary

  41-44.

  K. Rédei

  I. Veperdi

  Views:

  493

  Establishment of short-rotation energy plantations for fuel production has been of international interest for many years. Energy plantation experiments in Hungary have been conducted for a longer time. In the country black locust ( Robinia ps eudoacacia L.) is one of the most important stand-forming tree species, covering approximately 23% of the forested land (410 000 ha) and providing about 19% of the annual timber output of the country. This fast growing species seems to be suitable for energy plantations as well. So, in Helvecia (Central­ Hungary, sand-soil region) two energy plantation s were established u sing common black locust and its cultivars improved in Hungary. The spacing variations of the common black locust were: l.5x0.3 m, I .5x0.5 m and l.5x 1.0 m. At the age of 5 the closest spacing ( 1.5x0.3m) produced the greatest annual increment in oven-dry weight (6.5 t ha·1 yr- 1). In the trial with black locust cultivars planted in spacing of 1.5xl.0m, at the age of 7 the highest annual increment in oven-dry mass was produced by the cultivar ' Ulloi' (9.7 t ha-1 yr- 1) followed by the common black locust (8.4 t ha-1 yr- 1) and the cultivar 'J tiszkiseri (1.6 t ha·1 yr- 1). The trials have verified that in temperate climate the increment in oven­ dry dendromass of black locust energy plantation s has ranged from 6 to 12 t ha·1 yr·1. On the basis of the trials' evaluation the quantity of dendromass mostly depends on site quality, species and cultivars, as well as on the initial spacing (plants per hectare).

• Effect of Erwinia amylovora infection on peroxidase enzyme activity in resistant apple cultivars

  37-39.

  K. Kása

  M. Hevesi

  M. G. Tóth

  É. Stefanovits-Bányai

  Views:

  436

  Two apple cultivars that display enhanced resistance to fire blight (causal agent: Erwinia amylovora) were selected. The aim of the present study was to characterize the peroxidase (POD) enzyme activity of `Szemes alma' (a historical cultivar) and MR-03, (a Hungarian multiresistant hybrid of 'Prima') and compare them to susceptible 'Jonathan M 40' and resistant 'Remo' controls. Peroxides enzyme activity during E. amylovora infections was investigated in artificially infected apple shoots. Increases in enzyme activities were observed in a `Jonathan M40' and in 'Remo', MR-03, `Szemes alma' cultivars. There was a consistent relationship between total enzyme activity and fire blight disease severity. High activity of the peroxidase was positively correlated with the degree of resistance to fire blight. A general hypothesis that POD activity is related to fire blight susceptibility/resistance is supported by our results.

• Promising black locust (Robinia pseudoacacia L.) cultivars in Hungary

  18-20.

  K. Rédei

  Zs. Keserű

  I. Csiha

  J. Rásó

  M. Takács

  Views:

  609

  In Hungary, black locust (Robinia pseudoacacia L.) is one of the most important exotic stand-forming tree species, growing mostly under unfavourable ecological conditions. Considering the climate change effects its importance is increasing in many other countries. As a result of a selection programme, several black locust cultivars have been improved for setting up cultivar trials. In the paper four black locust cultivars were evaluated in Central Hungary under arid hydrological and brown forest soil conditions. Significant differences (P<5%) were found in height, DBH, mean tree volume and average stem form value (SFV).  At the age of 35 the cultivar ‘R.p. Jászkiséri’ appeared to be the most promising one for yield production and ‘R.p. Zalai’ for SFV.

• Comparative study of different fertile groups in plums

  71-76.

  D. Surányi

  Views:

  340

  The plum traditional fruit species in Hungary, several local cultivars was born in the different grower's districts. The author that investigated, that are morphological differences between an odds find self-fertile, self sterile (with functional stamens) and male sterile plum cultivars. For it thought about main questions of a scientific debate sown up and the study this way gave reactions totalize. There were in three fertile groups 8-8 type of feature plum cultivars in periods of 1992-2001, respectively 1993-1999. It was founded by author big odds found the troops on the basis of 9 traits between. Pistil length of self sterile cultivars very typical, such as sesquipedalian flower peduncle of the self-fertile plums and the hypoandry of male sterile cultivars. The relative stamen number and the pollen viability as well significant odds gave.

  The average fruit mass and sharka infection of self-fertile plums this troops extreme work. According to cultivar's averages the shark symptoms standard the right correlation the singular traits, but those one part of her with each other not shown connection.

  The annuity potencies underdeveloped the troops behind and the troops within cultivar's differences had case significance. The results usable the male sterile cultivars and progeny further its investments.

• Freeze Susceptibility of Fruit Buds in 67 Apple cultivars in Hungary

  29-35.

  M. G. Tóth

  Views:

  235

  Frost damage is one of the most important risks of apple production. Outstanding importance has been attributed to the frost resistance of flower-buds as decisive sites of fruit production. Browning of plants parts and tissues exposed to natural weather adversities are considered as effects of frost. In Hungary, frost damage on flower buds of both the market and new cultivars has not been assessed earlier. Observations referring to the consequences of frost damages of over four critical years, marked by their peculiar winter and spring frost hazards. Parallel observations have been made in four sites of the growing area in the Great-Plain region. 67 apple cultivars have been assessed. Each cultivar was represented by 3 trees, which were sampled at about 1-1.5 m height over ground, where the buds or inflorescences were picked for the purpose to assess the injury. The buds and flowers are cut longitudinally and rated visually according to the extent of browning of the organs and tissues. Susceptibility of different organs of the flower (pistils and anthers) were rated separately. According to our results, most resistant to spring frosts are the following cultivars: 'Gloster', 'Granny Smith' and appreciable tolerance is attributed in 'Gala' and 'Jonathan' with derivatives. Preliminary results that among the scab resistant cultivars, `Baujade', 'Rewena', 'Liberty', `Resi' and 'Renora' are rather frost resistant. Information, lacking hitherto, is obtained upon 'Reka' and 'Reglindis' as for their increased susceptibility.

• Evaluation of crop yield and fruit quality in organic apple production

  7-10.

  I. Gonda

  N. Rakonczás

  I. J. Holb

  Views:

  4133

  In this study, crop yield and fruit quality parameters (soluble solid concentration, sugar, total acid, and vitamin C content) of 15 apple cultivars including old, resistant and currently grown cultivars. The highest fruit yield among all 15 cultivars was obtained on CV. Jonagold with 15.5 kg/tree, while the lowest yield was measured on the resistant cultivar Reanda with 8.1 kg/tree. There were no significant differences among the cultivars in fruit diameter ranging from 70 mm in the case of cv. Húsvéti rozmaring to 82 mm for cv. Mutsu. Values of soluble solids concentration of the cultivars varied between 15.5% for cv. Téli Banán and 19.2% for cv. Renora. Sugar content values showed a similar tendency to soluble solids content. The highest and lowest total sugar content was observed on cvs. Jonagold and Renora and cv. Re­tina with 17% and 12.4%, respectively. Total acid content values ranged between 0.18% and 0.53% for cvs. Jonagold and Remo, respectively. Values of vitamin C content for the 15 apple cultivars varied between 2 mg% and 4 mg% for cv. Retina and cv. Mutsu, respectively.

• Evaluation of the growing and fruit bearing characteristics of the ‘Lapins’ sweet cherry cultivar grafted on rootstocks with different vigor

  15-18.

  Á. Csihon

  K. Bicskei

  P. Dremák

  I. Gonda

  Views:

  710

  Sweet cherry is currently considered as a fruit with high interests. The amount of the produced yield is well saleable in the world and also in Hungary year by year, moreover often there is a shortage with the high quality fruits. Researches with the sweet cherry production focus on the intensity growing all over the world, namely the realization of producing with small trees ensuring high quality and quantity. In our examinations ’Lapins’ sweet cherry cultivar was evaluated grafted on rootstocks with different vigor (Gisela 5, Gisela 6, Colt) at the University of Debrecen, Pallag Experimental Station. According to our results trees grafted on Colt rootstock can be described with very low yields due to the excessive high vigor. Trees with Gisela 5 and Gisela 6 rootstocks showed excessive high productivity, as size of the fruits did not reach the required values.

• First results of varios sour cherry cultivar on Oblacsinska as interstocks and Prunus mahaleb rootstocks

  87-90.

  H. G. Davarynejad

  J. Nyéki

  E. Davarynejad

  T. Szabó

  Z. Szabó

  Views:

  13867

  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.

• Effect of training system on the incidence of Stigmina carpophila and fruit size and weight of European plum (Prunus domestica)

  78-80.

  B. Molnár

  I. J. Holb

  Views:

  558

  In a two-year study (2017-2018), the aim was to determine the incidence of shot hole disease (Stigmina carpophila) on plum cultivar ’Čačanska lepotica’ in four different training systems with tree spacings of 4 x 1.5, 4 x 2, 5 x 2.5 and 6 x 3 m. Fruit size (width and length) and fruit weight were also assessed during harvest of fruit in the four training system. Cultivar ’Čačanska lepotica’ was susceptible to shot hole disease and showed shot hole symptoms in both years and in all training systems. In 2017, the highest disease incidence was observed in the 4 x 1.5 m plot (34% in June and 85% at the end of September). In June and July, the 6 x 3 m training system had the lowest disease incidence. In August and September, the 5 x 2.5 m training system had the smallest incidences of the disease among the training systems. In 2018, except for one assessment date (18 August) the 4 x 1.5 m plot had higher incidences than the other three training systems. Training system and years had almost no effect on fruit size, but there were some differences in fruit weight among the training systems.

• Historical apple cultivars that display high level of resistance to fire blight

  19-23

  K. Kása

  M. G. Tóth

  M. Hevesi

  Views:

  294

  Following the first outbreak of fire blight caused by the bacterium Erwinia amylovora (Burrill) Winslow et al. in Hungary, we have started research with the aim to screen domestic gene sources, mostly historical Hungarian apple cultivars, for disease resistance as part of an apple breeding program for multiple resistance. The present study was conducted with the aim to choose the most tolerant historical apple cultivars among 25 selected cultivars by screening their behavior towards fire blight under controlled conditions. Six cultivars were shown to be the most disease tolerant: `Batul', 'London pepin', Nemes Sóvári Alma', `Sikulai', `Szemes alma', Wilmos renet'. We evaluated these cultivars by investigating both morphological- characteristics under original environmental circumstances and fruit quality. The cultivars had a remarkable degree of fire blight resistance compared to the control cultivars. These were not competitive with the commercially grown 'Jonathan M40' during cultivar tests but on the basis of certain characteristics they could serve as genetic sources for breeding new varieties.

• Abnormalities of the stigma of sour cherry cultivar

  31-33.

  H. G. Davarynejad

  T. Szabó

  Z. Szabó

  J. Nyéki

  I. J. Holb

  Views:

  4810

  The objective of this study was to evaluate the ratio of blackness of the surface of stigma of sour cherry cultivars. At the full bloom time of sour cherry 100 new opened flowers were marked in the internal (Inside), external (outside), bottom and upper parts of the crown of each cultivars including sour cherry cultivars ‘Érdi bőtermő', `Debreceni bőtermő', `Kántorjánosi', 'R. clone', 'Petri', Pándy', and 'D. clone'. The trees were replicated four times. The numbers of flowers with black stigma were counted and the percentage of dead stigma was calculated. In addition, tissues of black stigmata were investigated for blossom pathogens by microscopy. After flowering time the fruit set of the marked flowers counted and then percentage fruit set was calculated. Numbers of counted flowers were between 300 and 980 depending on the four position of the tree. Black color of stigma could be seen only on three cultivars (`Debreceni bőtermő', Érdi bőtermő' and 'Petri') out of seven assessed cultivars. The highest numbers of black colored stigma were found on cultivar ‘Érdi bőtermő' which ranged between incidences of 12 and 21%. Black stigma was never able to produce a fruit set. Microscopic examination revealed no pathogens associated with black stigma. Different part of the tree resulted different amount of black stigma. Black stigma was the largest on the outer part of the tree on cv. 'Érdi bőtermő' but also bottom part of the tree also produced larger number of black stigma on cvs. `Debreceni bőtermő' and ‘Érdi bőtermő'. Though symptoms were not typical to frost damage, we believe that black stigma is probably due to environmental factors during flowering. This might be associated with late spring cold coming from the soil surface as the bottom and outer part of the tree was more suffered from the disease.

• Six promising selections from the Hungarian apple breeding program for multiple resistance

  23-28.

  M. Tóth

  Views:

  313

  An apple breeding program has been carried out at the Department of Fruit Science for more than a decade. Several apple selections have been released from the progenies of crosses in 1992 and 1993. Six candidates were submitted for national recognition out of the hybrids examined for more than a decade. The six selections are resistant against all the three most important apple diseases (apple scab, powdery mildew and fire blight). Scab resistance is controlled by the Vf gene originating from the species Malus floribunda 821 and transmitted by cultivar Prima. Heterozygote Vfvf genotype of the six cultivar candidates was proved by molecular genetic examinations of Dept. Genetics and Plant Breeding. Characteristics of these selections from 'Prima' progenies are shown on the base of our own observations.

• Effect of N, P, K and Mg fertilizers on some vegetative and generative parameters of a sweet cherry cultivar

  27-30.

  Á. Csihon

  I. Gonda

  M. Orosz-Tóth

  S.-né Kincses

  I. J. Holb

  Views:

  930

  This two-year-study was aimed to provide results on the effect of nitrogen, phosphorus, potassium and magnesium fertilizer treatments (control, NP, NPK, NPKMg) on vegetative and generative features of the sweet cherry cultivar ‘Carmen’. Examinations were performed in an orchard planted in 2012 on Prunus mahaleb rootstock with spacing of 5 x 2.5 m. All treatments improved the vegetative features of the sweet cherry trees in both years of 2016 and 2017. Fertilizer treated trees increased trunk cross section area (TCSA) with 51.3-63.1%, while control trees showed 48.3% trunk growth increase. Yields of control trees were lower in both years (5.9-7.2 kg/tree), than that of the fertilized trees (7.8-11.3 kg/tree). Treatments also increased the phosphorus (16-22%), magnesium (12-20%) and potassium content (3.5-18%) of the fruits compared to control treatments.

• Floral attractivity of pear cultivar 'Cinderi'

  102-109.

  Á. Farkas

  J. Orosz-Kovács

  L. Gy. Szabó

  T. Bubán

  Views:

  409

  The regularities of primary attractivity have been studied at the pear cultivar `Cinderi' for two years. Nectar quickly evaporates from the totally open nectary surface of pear flowers exposed to environmental effects, and the rhythmicity of nectar secretion can be determined with difficulty. Flowers do not function according to a unified endogenous rhythm, the whole tree becomes continuously attractive for insects, since it attracts insects on more occasions during the day with some of its flowers. During the warm afternoon hours there is usually no measurable nectar production. Pollen shedding is most intensive in the afternoon hours. Pear flowers produce little and diluted nectar, which often does not come up to apicultural expectations. The age of the flower does not significantly affect the quantity and refraction of nectar. The flowers of pear cv. ‘Cinderi' are delayed homogamous.

• Vegetative parameters of apple cultivars in integrated and organic production systems

  15-18.

  P. Dremák

  Á. Csihon

  I. Gonda

  Views:

  482

  Success of apple production is highly influenced by the applied production system and the planted cultivar. In this paper growing characteristics of 39 apple cultivars were studied in integrated and organic production systems. These kind of parameters are less studied in the cultivar and training system examinations, although they have huge effect on the training and maintaining of canopy, on the pruning necessity, ultimately on the production costs. According to our results the thickness of the central axis of apple trees showed significant differences between the integrated and the organic systems. Axis of the trees with lower trunk thickness tapers more slightly in the integrated production system, than in the case of the trees with thicker trunk in the organic system. Thicker axis is not accompanied by thicker trunk, namely the thickness of the central leader starts to decrease stronger in the organic production system, compared to the integrated one.

• Some important growing characteristics of apple and apricot cultivars in two fruit growing regions in Romania

  51-56.

  S. Pantea

  Views:

  270

  The aim of this study was to determine some important growing characteristics of 5 resistant apple (Rajka, Rubinola, Topaz, Otawa and Goldstar) and 7 apricot (NJA 19, Goldrich, Harcot, Venus, Comando, Olimp, Cea mai buna de Ungaria) cultivars in two fruit growing regions in Romania from 2000 to 2003. Height of the apple trees (4-year-old tree) ranged between 1.96 m (cv. Topaz) and 2.39 m (cv. Rubinola). Diameter of the crown ranged from 0.96 m (cv. Goldstar) to 1.12 cm (cv. Rajka). The trunk diameter ranged from 3.5 cm (cv. Goldstar) to 5.0 cm (cv. Rajka). The surface of the trunk section was the lowest for cv. Goldstar (9.7 cm') and the largest for cv. Rajka (19.6 cm). Height of the apricot trees (4 years old tree) ranged between 2.69 m (cv. Venus) and 3.38 m (cv. NJA - 19). Diameter of the crown ranged from 2.59 m (cv. Comandor) to 2.77 m (cv. Cea mai buna de Ungaria). The trunk diameter ranged from 9.54 cm (cv. Goldrich) to 13.30 cm (cv. NJA - 19). Length of annual branches was the lowest for cv. Goldrich (45.1 cm) and the highest for cv. NJA - 19 (83.8 cm). Bud swelling of apricot trees began on 8 March for cv. NJA - 19 and ended on 11 March for the control cultivar (Cea mai buna de Ungaria). The blooming started on 16 March for cv. NJA - 19 and 27 Mach for the control cultivar. Duration of fruit growth was 89 days for cv. NJA - 19 and 128 days for cv. Comandor. When the temperature decreased to 1.5 °C (in 2001), percentage of viable pollen grains ranged between 48.86 % (cv. Olimp) and 91.57 % (cv. Venus). The germinating grains ranged from 31 % (cv. Olimp) to 90 % (cv. Harcot). Free pollination was the lowest for cv. NJA - 19 (29 %) and the highest for cv. Harcot (41%), while self-pollination ranged between 6 (cv. Olimp) and 11 % (cvs. Comondor and Harcot). Apple yield ranged from 16.65 t/ha (cv. Otawa) to 24.35 t/ha (cv. Rajka) and the differences varied from 4.45 t/ha to - 3.25 t/ha compared to the control varieties. Apricot yield ranged from 11.47 kg/ tree or 9.53 t/ha (cv. Cea mai buna de Ungaria), to 38.83 kg/tree or 27.34 t/ha (cv. Olimp) and the differences varied from 3 t/ha to 17 t/ha compared to the control varieties. Apple fruit weight ranged from 162 g (cv. Otawa) to 222 g (cv. Goldstar) and apricot fruit weight from 42.52 g (cv. Goldrich) to 68.38 g (cv. Comandor). Color, taste and aroma were very specific to cultivars.

• Disease progress of apple scab caused by Venturia inaequalis in environmentally friendly growing systems

  56-62.

  I. J. Holb

  Views:

  521

  Progression of apple scab epidemic in six apple cultivars, including two current and susceptible (Gala Must, Elstar), two old (Egri Piros, Darusóvári), and two resistant cultivars (Relinda, Releika), were described and analysed in a two-year-study, in two environmental-friendly growing systems (organic and integrated). Curves of disease progress, linear regression analysis of transformed disease incidence data and Area Under Disease Progress Curves (AUDPC) were used to characterise the epidemic processes of the selected cultivars. Cumulative disease progress curves showed continuous but asymmetrical scab development on the moderate or highly susceptible cultivars Gala Must, Elstar and Egri Piros, and on the tolerant or resistant cultivar Darusóvári and Relinda, in both systems. The cultivar Releika showed no symptoms either on fruit or leaf. In linear regression analysis, the best linearisation was given by logistic transformation. Adequate parameters leaf disease incidence rate, of obtained from a regression equation, were higher in the organic system than in the integrated system. Values of AUDPC showed great differences in leaf disease incidences among cultivars and between growing systems. AUDPC gave more differences for comparison of progresses of disease epidemic than growth rate of disease in different systems of disease control. Moreover, the obtained results were compared with similar studies on different pathosystems, and biological interpretations of the analyses are discussed below.

• Comparison of varying pollen source on productivity of sour cherry (Prunus cerasus L.) cultivars

  23-26.

  G. H. Davarynejad

  J. Nyéki

  T. Szabó

  J. Tornyai

  Z. Szabó

  M. Soltész

  E. Davarynejad

  Views:

  1136

  Fruit set of five sour cherry cultivars (‘Újfehértói fürtös’, ‘Éva’, ‘Petri’, ‘Pándy 279‘ and ‘Csengôdi’) of eight years-old trees grown in Újfehértó, located in the Eastern north part of Hungary have been studied over two years (2008 & 2009). Following reciprocally cross-pollination, free-pollination, self-pollination (autogamy) artificial self-pollination (geitonogamy) were studied. The results show that both maternal and paternal parent cultivates had significant effects on the percentage fruit set. Significant differences have been found in fruit set among years and among pollination treatments. Fruit set of free-pollinated Pándy 276 cultivar was low and seasonally highly variable. The yield of this cultivar on self-pollinated flowers was nearly 0%, and in this treatment the maximum yields did not reach 10% in any of the examined cultivars. There was no significant relationship in the fruit set of free-pollination and natural self-pollination treatments.

• Description of new sour cherry cultivars and cultivar candidates bred in the Research Institute for the Fruit Growing and Ornamentals

  81-82.

  J. Apostol

  Views:

  222

  Description of new sour cherry cultivars and cultivar candidates bred in the Research Institute for the Fruit Growing and Ornamentals

• Evaluation of fruit quality of old apple cultivars originating from the foot of the Carpathian Mountains, for utilization in breeding and in organic farming

  15-24.

  M. Tóth

  E. Balikó

  Zs. Szani

  Views:

  452

  In the frame of the apple breeding program at the Department of Fruit Science old cultivars found in the Carpathian basin were involved in examination as well. Beside testing susceptibility to fire blight (Erwinia amylovora of old genotypes (historical, local and regional cultivars) originating from scattered orchards of Visk (foot of the Carpathian Mountains), fruit quality was also evaluated and other open-field observations were made.

  According to the results of inner content examinations, 'Szemes alma' and 'Sikulai alma', chosen as gene sources for breeding to resistance against fire blight, had inner content values worthy to mention in some aspects, and competing with those of the control cultivar 'Jonathan'. The quality of 'Pónyik alma', also recommended as a gene source is confirmed by the data of earlier literature. Further three cultivars ('Batul', 'Vilmos renet', 'Zöld sóvári') also proved to be good based on resistance against Erwinia amylovora, the first two cultivars are suitable from the point of view of fruit quality, too.

  In our field observations, susceptibility to apple scab and powdery mildew was evaluated. Among cultivars selected from the foot of the Carpathian Mountains on the base of resistance against Erwinia amylovora, the production value of 'Szemes alma' is worsened by its high susceptibility to apple scab. Further selected cultivars ('Sikulai', 'Pónyik alma', 'Batul', 'Vilmos renet') are not too susceptible to fungal diseases and their fruit quality is also suitable, therefore they can be recommended for direct planting in ecological farming or in restoring scattered orchards.

• The effect of rootstock on the nectar production of apple cultivar `Idared'

  15-25.

  E. Nagy Tóth

  Zs. Orosz-Kovács

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  236

  Approaches based on the daily rhythm of apple flowers provide a new stage in nectar research, where the synchronous functioning of sexual organs is studied. In the flower biological studies the insect attraction of flowers was also studied. The two most important factors of insect attraction are the pollen- and nectar production of the flowers. From 1993 to 1998 we studied the food, that flower had to offer for the pollinating insects at different times of the day.

  Studies were carried out on 'Idared', one of the hybrids of 'Jonathan' apple cultivar. The fruit of 'Idared' is bigger than the fruit of `Jonathan'. It is bright red, transportable, has a bigger productivity and is not subject to Jonathan-spots. Concerning its inner characteristics, it is juicy, the flesh consistency is better than that of 'Jonathan', but its acid/sugar ratio is worse (Sansavini et al. 1981).