Search

Search Results

• Fire blight (Erwinia amylovora) resistance in apple varieties associated with molecular markers

  53-57.

  J. Sehic

  H. Nyboom

  L. Garkava-Gustavsson

  A. Patocchi

  M. Kellerhals

  B. Duffy

  Views:

  261

  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.

• Preliminary study on micro area based spatial distribution of powdery mildew in an organic apple orchard

  35-37.

  I. J. Holb

  Views:

  217

  In this study, the objective was to report a preliminary study on micro area based spatial distribution of powdery mildew in an organic apple orchard. Results showed that number of symptomatic plant part ranged between 11 and 20 on shoot and between 9 and 24 on fruit. Number of asymptomatic plant part ranged between 85 and 109 on shoot and between 133 and 206 on fruit. Disease incidence ranged between 13.8 and 17.6% on shoot and between 9.1 and 11.3% on fruit. Disease aggregation index ranged between 0.098 and 0.228 on shoot and between 0.043 and 0.108 on fruit. One of the four trees showed significant within canopy aggregation of disease for shoot powdery mildew symptoms in both years. For leaf powdery mildew, all tree exhibited random patterns in both years.

• Preliminary study on micro area based spatial distribution of Monilinia fructigena in an organic apple orchard

  19-21.

  I. J. Holb

  A. Rózsa

  F. Abonyi

  Views:

  213

  In this study, we aimed to report a preliminary study on micro area based spatial distribution of Monilinia fructigena in an organic apple orchard. Results showed that number of symptomatic fruit ranged between 22 and 42 in 2013 and between 25 and 35 in 2014. Number of asymptomatic fruit ranged between 111 and 187 in 2013 and between 119 and 167 in 2014. Disease incidence of fruit ranged between 19.7 and 23.2% in 2013 and between 19.1 and 26.5% in 2014. Disease aggregation index ranged between 0.111 and 0.335 in 2013 and between 123 and 401 in 2014. Three of the four trees showed significant within canopy aggregation of disease for fruit brown rot symptoms in both years. However, the remaining one tree exhibited random patterns during both years. Disease aggregation indicated a disease spread by fruit-to-fruit contact and/or an aggregated
  pattern of insect damage.

• Effect of the environmentally friendly production systems on the vegetative characteristics of apple cultivars

  11-14.

  P. Dremák

  Á Csihon

  I. Gonda

  Views:

  358

  In this study effect of the environmentally friendly production systems on the brunch cross sectional area of apple trees trained to free spindle canopy are presented based on the data of 39 cultivars. According to our results branch thickness of the apple cultivars located in the lower, middle and upper region of the tree are more homogenous in the integrated production system compared to the organic one. Therefore the severity of the annual maintain pruning must be necessarily more moderate in the integrated growing system, than in the organic production system.

• Experimental approach in apple tree nutrition

  9-13.

  T. Kállay

  E. Szűcs

  Views:

  134

  Authors present synthesis of experimental work, performed in the last decades, for better understanding nutritional behaviour of apple trees and related problems in fruit quality. There were evidences supporting possible deteriorating role of potassium in feeble physiological status of apples, if applied in excess. More intensive studies proved that higher potassium uptake into leaves and fruits might be also the result of increased sink power of individual fruits. Nevertheless early senescence of apples during storage and also sensibility to bitter pit were successfully related to the increased sink power of fruits, casual relations in excessive NPK fertilization, although increase in sink power need further investigations. Impaired weather conditions during early development of fruits, hostile orchard practices in pruning, thinning, irrigation and also unskilled application of growth regulators may also contribute in the enhancement of sink power and in weakened physiological status of apple fruits.

• Studies on the insect pollination of fruit tree species and on closely related topics in Hungary: a bibliography of research publications

  157-161.

  P. Benedek

  Views:

  165

  In the past decades fruit production has become more and more intensive and so the interest towards the bee pollination of fruit trees has increased in Hungary. Thus insect pollination research has become more intensive in the eighties and in the nineties. Recently, high density fruit orchards are planted of dwarf trees at more and more farms in Hungary and these need highly controlled growing practices involving insect pollination, too. This is a new challenge of insect pollination research in Hungary. So it seems to be worth to compile a list on research publications having been appeared so far to create a basis to the ongoing new research. Besides papers strictly on the insect pollination of fruit trees publications on some closely related topics, first of all on the nectar production and on other flower characteristics of fruit tree cultivars that directly influence bee activity have also been included on the list.

   

• Evaluation of fruit tree waterstress condition and transpiration with heat fl ux sensors

  leaf area index, evapotranspiration, water stress

  A. Nagy

  P. Riczu

  J. Tamás

  Z. Szabó

  M. Soltész

  J. Nyéki

  Views:

  253

  In this study the transpiration properties and response to heat stress of Granny Smith and Jonagold apple species were measured. The examinations were set at an orchard near to Debrecen. The chosen trees were two years old, without fruits, in 20l container, placed in the mixture of mulch matrix, wood chips and sawdust and grown at the same climatic conditions. One of the most important goals was to determine the leaf area of the trees which is a basic data for transpiration modeling. Leaf area was larger (signifi cance level p<0.05) in the upper part of the canopy to achieve larger photosynthetic surface. Jonagold species with less leaf number (–18% compared to Granny Smith) reached almost the same canopy area, than Granny Smith, due to larger leaf area of Jonagold. Another aim was to measure the transpiration rate of the apple trees. The transpiration measurements were carried out by sap fl ow meter. Only a small transpiration difference can be found between species. During the investigation time there were wet and cool as well as dry and extremely hot periods. In the case of dry and extreme hot periods the transpiration is decreased, which causes decrease in transpiration and enhanced the water stress of trees.

• Alternate bearing of 'Golden Reinders' and 'Summered' apples

  77-85.

  J. Racskó

  J. Nagy

  Z. Szabó

  M. Soltész

  I. J. Holb

  J. Nyéki

  Views:

  277

  The aim of the present study was to study the effect of biennial bearing (irregular yields) on the generative production of apple cultivars 'Golden Reinders' and 'Summerred' on M.9 rootstock. The observations were made at Nagykutas in West-Hungary for four years. The authors have studied the flowering time, flower density, fruit density, fruit drop, seed content, yielding and fruit quality in the on-year and off-year. Based on the results, it can be stated that the alternation does not cause a significant change in the flowering time of cvs. 'Golden Reinders' and `Summerred': the difference between the flowering time of trees in the on-year and off-year period was 0-1 day. However, there were significant differences in the flower density. 'Golden Reinders' proved to have a weaker tendency to alternation similarly to the statements of the literature. Alternation (off-year) was observed only in three years from the studied four years. While in the case of `Summerred', strong alternation was observed in all four years. In fruit density, there were differences among the cultivars and among the different cycles of biennial bearing. Fruit density (and its opposite, fruit drop) changed inconsistently in the period between flowering and harvest. In the case of 'Golden Reinders' and 'Summerred' 2 and 4 fruit drop periods were detected, respectively. In the off-year, the different periods were less distinct, in most cases they were overlapping each other. The dynamics of fruit drop was related to seed content per fruit. The lower the seed number was, the higher the degree of fruit drop was. In both the high- and off-year cycles, the number of seeds in fruits on the tree and on the ground increased with time. In the yield parameters (fruit number, fruit load, yield efficiency), the differences were greater among the yields of trees in the high- and off-year cycles for 'Summerred'. The fruit quality parameters were greatly influenced by the fruit load of the trees in the different alternation cycles. In general, it can be stated that fruit mass, diameter and height were lower on trees in the on-year. A similar trend could be observed in flesh firmness, cover colour and dry matter content, but the differences were smaller. 'Summerred' was more sensitive to the differences in fruit load.

• Production technology and fruit tree nutrition

  39-42.

  I. Gonda

  Views:

  152

  Fruit yield quality and quantity are effectively enhanced if healthy vegetative conditions are ensured. These optimal conditions — i.e. the balance between shoot development and yield — can be achieved by the rationalization of the production technologies, such as:

  • reduction of the size of the crown
  • adaptation of the severity and method of pruning to the conditions of the actual year
  • removal of the shoot tips
  • timely fruit thinning

  By establishing an improved level of plant nutrient uptake, this will ensure a healthy balance between shoot growth and yield.

• Evaluation of fruit tree transpiration with heat flux sensor

  11-13.

  P. Riczu

  A. Nagy

  J. Tamás

  Views:

  202

  One of the biggest professional challenges of the following years is to develop the water resource management for apple trees. In order to know the water consumption of plants, some traditional and modern methods could useful. In our research the sap flow measurement of the plants were carried out. We have analyzed the transpiration properties of the trees in the investigation period. In order to compare the transpiration of the trees, the leaf areas were scanned and evaluated. Beside these measurements, soil water properties were determined by tensiometers, thus it makes possible to observe the soil-plant-atmosphere system.

• Pomology of gene resources bearing resistance to Erwinia amylovora

  29-33.

  M. Tóth

  Views:

  138

  The ecological farming and an increasing demand for healthy fruits free from chemical residuals necessitated the reevaluation of the existing cultivars and breeding suitable cultivars for the new requirements. We have gathered the old genotypes known in the Carpathian Basin, and we have selected the most suitable ones according to fruit quality and resistance to diseases in the last fifteen years. The main aim was the selection of resistant genotypes against fire blight and powdery mildew as gene sources for our breeding program. On the other hand, we consider the best quality traditional cultivars as extensive landscape elements (wayside tree rows or extensive squash producing plantations).

  During the pathological evaluation 'Szemes alma', 'Pónyik', 'Sikulai', 'Tordai piros 'cavil' and 'Szabadkai szercsika' cultivars proved to be good resistance sources (due to their outstanding resistance to fire blight). The latter four cultivars are not susceptible even to fungal diseases, and their quality is also acceptable so those are commendable for ecological farming or for renewing the sparse orchards. According to fruit quality and low susceptibility to diseases 'Batul' and 'Vilmos renet' can also be offered for extensive organic production.

  We have made original or renewed pomological descriptions of the selected cultivars, and we also publish their characters according to the terms of UPOV TG/14/8 based on to our evaluations.