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  • Effect of acidity on growth rate and stroma formation of Monilia fructigena and M. polystroma isolates
    63-67.
    Views:
    197

    The effect of acidity (pH) ranges on the mycelial growth and stroma formation of Monilia fructigena Pers: Fr. and of M. polystroma van Leeuwen was determined on agar plates and apple fruits. Four isolates of each of the brown rot fungi and two apple cultivars, `James Grieve' and 'Cox's Orange Pippin', were used for the study. For the agar plate study, a range of the initial pH was prepared from 2.5 to 6.5. The dishes were inoculated with a 4 mm plug of each isolate and incubated at 23 °C in darkness. The mycelial growth was measured after 1.5, 4, 7, 10 and 20 days of incubation. After a 30-day incubation, stroma formation was determined by image analysis and weighing of mature stroma. In the fruit experiment, both cultivars were inoculated with one isolate of M. fructigena and of M. polystroma. The pH changes were determined after 7, 14, 28 and 35 days of incubation in both healthy and inoculated fruits. The fastest mycelial growth was at pH 4.5 for M. polystroma and at pH 3.5 for M. fructigena. After a 30-day incubation, M. polystroma isolates produced twice or three times more stroma compared to M. fructigena isolates. For both brown rot fungi, the amount of mature stroma increased from pH 3.5 to 5.5, and then decreased at pH 6.5. Results of the.fruit experiment showed that healthy fruits were quite acidic (pH < 3.5), but pH rapidly increased in the inoculated fruits for both cultivars, reaching pH 4.6-5.4 depending on cultivar and fungus isolate. On both cultivars, the stroma developed at a significantly higher pH for M. polystroma than for M. fructigena. Biological and practical implications of the results are discussed.

  • Effects of DMI and strobilurin fungicide combinations on scab and powdery mildew incidence in apple production: a preliminary study
    37-39.
    Views:
    258

    The aim of our study was to evaulate the effectiveness of four DMI and strobilurion fungicide combinations in a season-long disease management programme against apple scab and powdery mildew in two integrated apple orchards on cultivar Jonagold. The four spray programmes were: i) standard, ii) DMI dominant iii) strobilurin dominant, and iv) DMI and strobilurin dominant. Apple scab incidence as generally high in both orchards in the standard fungicide treatment plots ranged between 21.8 and 26.4%. Leaf scab incidence was higher in all treatments compared to fruit incidence. Scab incidence was generally higher at Mándok compared to Ófehértó. In both locations the lowest scab incidence was assessed in DMI dominant treatment ranged between 5 to 10.7%, which was not signifi cantly different from the DMI and strobilurin dominant treatment. Powdery mildew incidence was generally low in both orchards in all fungicide treatments ranged between 0.002 and 0.5%. Although there were no signifi cant differences among treatments, the lowest powdery mildew incidence was assessed in the DMI and strobilurin dominant treatment in Mándok and in the strobilurin dominant treatment in Ófehértó.

  • Molecular characterization of apricot (Prunus armeniaca L.) cultivars using cross species SSR amplification with peach primers
    53-57.
    Views:
    241

    Apricot takes an important place in Hungarian fruit production. Considering morphological characteristics of apricots it was concluded that the genetics background of European cultivars is very limited. Molecular markers and their use for genotyping have revolutionized the identification of cultivars. In a classic apricot breeding program, it is important to be able to establish unique DNA profiles of selections to identify them unambiguously and to determine their genetic relationship. Presently SSR is far the most frequently performed technique for genetic diversity studies. In this study there were used peach and apricot primer pairs from four different sources in order to examine microsatellite polymorphism among cultivars and investigate relationships among them. The possibility of cross species amplification among different Prunus species using SSR primers allowed us to use primers developed in peach to study genetic diversity in apricot. In this work, 90% of the primers used were able to amplify SSRs in apricot and more than half of them were polymorphic. With the 10 primer pairs utilized were proven to be sufficient to set unique fingerprint for several cultivars studied. The obtained dendrogram classified of the 45 cultivars included in this study into two major groups and several subgroups.

  • The effect of rootstock on the tree size of apricot cultivars
    57-58.
    Views:
    143

    The apricot is propagated on several kinds of rootstocks in Hungary. The main aspects of selecting rootstocks are as follows: adaptability to environmental circumstances, primarily soil conditions, ensuring the tree size that complies with the cultivation method, and compatibility with the grafted cultivar. At advanced, intensive orchards rootstocks ensuring smaller tree size are privileged. For the establishment of the appropriate cultivation system, it is important to be aware of the expected growing vigour and tree size of certain cultivar­rootstock combinations when the orchard is designed. In the course of our experiment the size of 15-year-old trees of 4 apricot cultivars were examined on several rootstocks at an orchard in Siófok. On the basis of the data measured for each cultivar-rootstock combination, it can be stated that trees on wild apricot (P. armeniaca) rootstocks are the largest in size. Trees on prune (P. domestica) rootstock have 10-15% smaller crown volume than the previous combination. Trees on bullace (P. insititia) rootstock have the smallest tree size and their crown volume is 30-50% smaller than that of the trees on P. armeniaca rootstock. Thus, the application of prune and bullace rootstocks is beneficial at intensive apricot orchards as the size of trees can be reduced by their usage. However, their compatibility with the cultivars and their adaptability to the ecological conditions of the production site have to be tested before applying them widely. In the course of our research incompatibility was not experienced for any of the cultivar-rootstock combinations examined. Nevertheless, the drought tolerance of the rootstocks examined showed significant differences. Trees on P. domestica or P. insititia rootstock requires more water than those on P. armeniaca rootstock, therefore, they have to be irrigated.

  • The uses of wolfberry (Lycium barbarum L.) as a fruit in an international breadth of view
    7-13.
    Views:
    310

    Lycium barbarum is known exclusively as an ornamental plant in Hungary, and is planted so, as popular belief deem it a toxic plant. The plant’s fruit receives great respect in countries abroad, thus, due to its favourable content values the Lycium has achieved the title of ‘biological gold mine’. The last couple of years has seen the import of Lycium shrubs and its corresponding products, dried goods or in the form of various processed products which have been marketed and sold at extreme prices (under name of Goji, Wolfberry, Lifeberry). Our goal was to examine the similarities of the content values of wolfberry found in Hungary and those cultivated abroad. Along with Miklós Józsa the domestic Lycium population was surveyed based on foreign examples, between the years 2009 and 2011. Those defined sweet and largefruited were selected for further investigations to be set into a clone repository. This clone repository– which contains 67 different clones from a number of regions of Hungary – was established in the nursery of Dr. Miklós Józsa, located in the city of Szombathely. The phenological and morphological characteristics and the fruit ripening and quality indicators of plants in the clone repository were investigated. Six ‘best’ clones – selected based on flavour, disease-resistance and vegetative characteristics (plant size, fruit set, yield and fruit size) were analysed based on their content values. The control plant was a cultivar imported by a delivery service, found also in growing. In addition to the results of the selection, the results of the content values of the six selected ‘best’ clones (total soluble sugar content, glucose-fructose ratio, carotene content, FRAP value) is documented in this paper. Further, based on the resulting information the possibilities of the fruit’s utilization are suggested. Significant differences were measured in the vegetative characteristics of the clones (plant size, fruit set, yield and fruit size) and of those of
    its inner content values. The resulting properties are considerable in regards of the plant’s introduction into cultivation and also utilization. Based on growing characteristics, more favourable clones were selected than the foreign varieties already in growing. Those clones selected by us have had similar or better content values than foreign breeds. The investigation of these content values is still in progress.

  • Specialities of the vegetation start and level of primary fruit set affect fruit quality
    17-22.
    Views:
    197

    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.

  • Postharvest methyl jasmonic acid and hot water can reduce the internal breakdown and quality loss of apricot fruit at shelf life
    31-34.
    Views:
    252

    The aim of this study was to investigate the postharvest effect of methyl jasmonic acid (MJ) and hot water on internal break-down and quality loss of apricot fruit under shelf life conditions. Cultivar Flavor cot apricot fruit were used to treat with water as control treatment, with 0.2 mmol/L MJ and with hot water 35 oC for 5 min. Fruit were stored at room temperature and were examined every 2 days for internal break-down and quality loss. Results showed that treated fruits with MJ and hot water showed the lowest weight loss and the highest firmness during all assessment times. Control fruits showed losing of customer acceptance from the day 2 of shelf life and then decreased dramatically to approximately loss all the acceptance at day 8. The SSC showed sever reduction in untreated fruit after day 6 at shelf life. Total phenol content reduced and polyphenol oxidase (PPO) increased in all assessment times for all treatments. Meanwhile MJ showed the best values for phenol content and lowest PPO activity. The results supported the idea of using some elicitors like methyl jasmonic and hot water treatments to enhance shelf life of apricot fruit.

  • Possibilities of blossom and twig blight management in organic stone fruit production
    103-105.
    Views:
    239

    In this study, possibilities of environmentally-benign plant protection against blossom and twig blight were summarized for organic stone fruit orchards. Symtomps of Monilinia laxa (Aderh. & Ruhl.) Honey) were described and then cultivar susceptibility to blossom and twig blight was discussed. Several sustainable plant protection methods were selected and discussed in details such as mechanical, agrotechnical, biological, and other non-chemical control possibilities (stone powders, plant extracts and restricted chemical materials).

  • Impact of potassium fertilizers with different active ingredients and dosages on potato yield in experiments in the Nyírség region
    71-74.
    Views:
    171

    A five-year experiment was carried out in the Nyírség on its characteristic soil type, brown forest soil to investigate the impact of three types of potassium fertilizers (potassium chloride, potassium sulfate and Patentkali) in three different dosages (80, 160, 240 kg/ha K20), under non-irrigated conditions applying the same dosages of N, P in all treatments (the applied amount was different between years) in 10 treatments including the control on 50 m2-parcels with 3 or 4 replicates. The test plant was cultivar Desiree, Kondor, Agria and Pannonia in 1998 and 2000, 2001, 2002 and 2003, respectively. The obtained yields were analyzed by an analysis of variance. Based on the five-year results, the highest yields on the acidic sandy and sandy loam soils were obtained in the treatments with 530-800 kg/ha Patentkali containing 30% of K and 10% of magnesium active ingredients in addition to the same amounts of N and P applications. The dosage of 530 kg/ha Patentkali contains 160 kg/ha K+ 53 kg/ha Mg active ingredients, while the dosage of 800 kg/ha Patentkali contains 240 kg/ha K+ 80 kg/ha Mg active ingredients. It can be concluded that the potassium chloride fertilizer (KCI) was the least effective as regards yields and Patentkali proved to be the most effective fertilizer, it had higher yields than even those of potassium sulfate, the difference in the 160 kg/ha treatments was 17.7%, which was a significant difference. Based on the results of the multi-year experiment, we recommend to apply 530 kg/ha Patentkali fertilizer (160 kg/ha K+ 53 kg/ha Mg active ingredients) for the fertilization in potato under non-irrigated conditions on the acidic sandy and sandy loam forest soils of the Nyírség, which proved to be the most effective treatment and with which we could obtain 30 t/ha yield in the average of the years (with the simultaneous application of N and P).