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Some microbial treatments against the tomato leaf miner; Tuta absoluta (Merick) under natural field conditions
81-84.Views:188In an attempt to find more effective methods and safety to control the tomato leaf miner, Tuta absoluta, this research was conducted to study the efficacy of the four bio-treatments ; two bacterial isolates (Bacillus subtilis. and Pseudomonas Fluorescence), one fungal isolate Trichoderma viride) and Spinosad as a microbial insecticide compared with the most common insecticides used against the dipterous and lepidopterous leaf miners in Egypt; Profenofos and Aphox. In the two successive seasons; 2011 and 2012, the fungal isolate Trichoderma viride achieved the lowest infestation(numbers of infested leaflets, mines, infestation percentages) which were 167, 195, and 21.9% resp.in season 2011 and 198, 222 and 26.2% resp. in season 2012. While the highest infestation was occurred in case of using the insecticides, Aphox (423, 559 and 55.9% resp.& 384, 839 and 72.2%. and Prohpenofos (436, 562 and 57.7% &391, 534 and 51.7% resp.).during 2011 and 2012 respectively. The other treatments occupied the intermediate levels. On the other hand, the yield of tomato fruits was increased by 75% over the check in case of plants treated with Trichoderma viride isolate, but the pesticide treatment given weak or no impact in increasing tomato crop. In season 2012, the infested tomato fruits percentages with T. absoluta larvae and Rhizoctonia soil rot disease(that Frequently observed incidentally) were recorded the minimum levels obtained by spraying Trichoderma viride isolate(21.38 and 10.32% resp.). In contrast, the maximum levels were recorded in Prophenofos (44.87 and22.78% resp.) and Aphox treatments(47.22 and 27.78% resp.).
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Heat waves in Hungarian plant production
113-118.Views:188A momentous inference of heat waves is the economic effect. The main demage after the human problems will caused by theese extreme events in agriculture. For example a long hot peiod without any percipitation can exterminate not only the annual yield, but also it can demage or in extreme situation it can destroy the whole orchard. Especially endangered most of the fruits, because an extreme summer with high temperature which usually goes hand in hand with an arid period can modify growth of the plant. Our investigations show that according to the most widely accepted climate change scenarios heat waves are expected to be essentially longer and hotter than in the past. It might happen that events we now define as heat waves last through entire summer. Although it will not be general, the length and intensity of present heat waves could also multiply. Based on data provided by some global circulation models, we might be face an event that exceeds the hottest heat waves of the 20th century by as much as 12 °C. This study also offers a survey of the methodology of heat wave definition. Besides traditional calculations, we present two unconventional methods by introducing minimum and maximum temperature heat waves. We show in what points this approach is different from those usually adopted and what extra information it may offer.As an extension of the usual studies, with considering the length of events, we analyse the development of two variants – temperature and duration – and, as a result, classify the extreme heat events according to both length and intensity.
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Calculation of climatic probability of winter and spring frost damages in the main peach and apricot growing districts of Hungary
99-106.Views:201The probability of winter and spring frost damages experienced in peach and apricot plantations has been assessed in 5 growing regions of Hungary (Szeged-Szatymaz, around the lake Balaton, Mecsekalja, hills of Buda, Mátraalja) and (Mecsekalja, hills of Buda, PestGodo116, Duna-Tisza Mize, Matra-Bükkalja) during the period between 1951 and 2000.
Frost tolerance of flower buds on a given shoot sample is expressed by the mean value assessed after frost damage (LT50), and the meteorological records of the growing sites raised between 1951 and 2000 are used to calculate the probability of frost damage. In peach, the difference between growing sites and between varieties may become two fold as for the chance of repeated frost damage at a probability of 50 %. In apricot, the probability of frost damage may exhibit differences between growing sites up to 20 % as for susceptible varieties, and 16 % for frost tolerant varieties. Frost damage may vary between 4 and 18 % depending on the genuine frost tolerance of the varieties. Peach is afflicted by low temperature causing substantial losses of yield at the highest probability in the region Szeged-Szatymaz and at the lowest in Mátraalja. Apricot is, on the other hand, most endangered in the Duna-Tisza Mize region, while the lowest probability of frost damage is expected around Mecsek and Buda.
The critical period of frost damage in the mid of January in Szeged-Szatymaz region, in Mecsekalja the mid of February showed the highest probability of frost damage. All growing sites are frequented at high chances by frost damages occurring during and closely after the blooming period. Duna-Tisza köze is mainly afflicted in early March, whereas Mátra-Bükkalja in mid of January and each March.
The probability of temperatures below zero degree has been assessed in all the 5 regions observed. Around April 5-8 the probability of freezing temperatures diminishes steeply at all sites, whereas the risk of frost increases again around April 9— 11. That climatic peculiarity of should be taken into consideration in choosing growing sites or varieties.
Postulating the effects of a global warming up of the climate, the chances of avoiding frost damages at different growing sites by delaying the blooming dates are considered. According to our calculations, the delay of blooming by 5 days may diminish the risk of frost damage by 4-20 % at the growing sites examined, whereas a delay of 10 days reduces the risk by 37-85 % in both fruit species.
Calculations offered an answer on the question of climatic changes, whether the probability of winter and spring frosts damage changed during the 50 years. The long list of data shows the diminishing chances of winter frosts, while the probability of temperatures risking spring frost damages increased after the early 1970-es up to now.
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Determination of (in)compatibility genotypes of Hungarian sweet cherry (Prunus avium L.) accessions by PCR based methods
37-42.Views:173Sweet cherries (Prunus avium L.) are generally self-incompatible and pollinator cultivars are needed in orchards for reliable yield. In Hungary, choosing the appropriate cross-compatible cultivar pairs has so far been based on traditional test-crosses in the field. In recent years PCR-based methods that allow the identification of the S-alleles responsible for compatibility have been elaborated. We have determined the S-allele constitution of 24 cultivars and four selections important to Hungarian growers and breeders using PCR-based methods developed at Horticulture Research International, East Malling. The 28 accessions had various pairs of 9 alleles including one new allele, Sr. They could be assigned to 12 of the existing incompatibility groups or to a new group (S4S12) for which the designation 'Group XXVII' is proposed. The cultivars `Krupnoplodnaja' and 'Rita' had novel genotypes, S5S9 and S5Sx, respectively and can be placed into group 0 that holds universal pollen donors. The genotype of the cultivar ‘Hedelfingeni óriás' grown in Hungary was found to be S3S4 and therefore different from the cultivar `Hedelfingen' that is widespread in Western Europe.
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Evaluation of the growing and fruit bearing characteristics of the ‘Lapins’ sweet cherry cultivar grafted on rootstocks with different vigor
15-18.Views:408Sweet 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.
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Effect of hail protecting nets on the quality of apples
77-80.Views:249Today, successful fruit growing depends largely on the security of production. Among the technological elements of a secure growing system, the use of hail protection nets serves special attention. Components of security are the regularity, conspicuous large yields with excellent quality, which determine the prices and profitability as well (Szabó et al., 2010). In the European Union, most of the apple growing countries produce higher yields by 10-20% than Hungary. The conditions of better yields are partly due to a more favourable ecological milieu, partly to more developed technologies and serious discipline of the operations. Our own competitiveness could be developed first of all in those moments. As a consequence of global climatic changes, excesses of weather, i.e. hail-storms became more frequent. Different methods of protection against hail are developed abroad but also in Hungary. The examination of effects of the hail protection nets compared with the check without nets has been the purpose of our experiments. The growing system was the intensive one with high planting densities. Fruits of the two subsequent years have been compared as grown with and without hail protective nets. It turned out that in one season when shoot growth was stimulated, the shadowing effect of the net increased in addition the growth and at the same time braked the differentiation of flower buds, which exerted negative effects on yield of the next year. Let alone this phenomenon, the quality of fruits was not influenced by the hail protection net.
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Effects of a band application of polyolefin-coated diammonium phosphate on the nutritional quality of rhubarb and Swiss chard
39-42.Views:675Dietary intake of large amounts of nitrates and oxalates presents a health hazard. In this study experiments were conducted with two oxalate accumulating vegetables rhubarb (Rheum rhabarbarum L.) and Swiss chard (Beta vulgaris L. var. cicla L.)) using POC-DAP in order to improve their nutritional quality. In the rhubarb experiment oxalate content was significantly reduced by band application of POC-DAP, while effects on ascorbate and nitrate contents were ambiguous. The improved nutritional quality in the POC-DAP treatment was rather a cause of ammonium nutrition than a cause of less amount of released fertilizer nitrogen. In the Swiss chard experiment oxalate and nitrate contents were reduced, while ascorbate content was increased by a band application of POC-DAP. The improved nutritional quality in the POC-DAP treatment was the cause of both the less amount of released nitrogen and the realised ammonium nutrition. It was also found that by using POC-DAP for Swiss chard cultivation, labour and energy costs of top-dressings could be eliminated without yield decrease. It was concluded that the nutritional quality of rhubarb and Swiss chard could be improved by using a band application of POCDAP.
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Susceptibility of European pear cultivars to Venturia pirina Aderh. infection at a variety collection in Hungary
41-47.Views:280Field sensitivity of 271 European pear genotypes were evaluated in a large variety collection of pear in Hungary during a nine years survey. Substantial differences were detected in the rate of pear scab infection of leaves and fruits. Some 18 per cent of the inspected genotypes remained completely free of infection even in the years with weather favouring to the disease. On the other hand, 78 % of the inspected genotypes were infected in some or more extent. The rate of infection was generally higher on leaves than on fruits. 18.6 % of the genotypes inspected were tolerant to leaf infection and their majority (81.1 %) were tolerant to fruit infection. Some one fi fth of the genotypes (19.7 %) were highly susceptible to leaf infection but only minor rate of them (2.2 %) were highly susceptible to fruit infection. There were 44 genotypes that could be regarded as tolerant to pear scab leaf and fruit infection under fi eld conditions. Some of these genotypes may be suitable to commercial pear growing with highly reduced chemical control against pear but their yield capacity and fruit quality should be evaluated.
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Specialities of the vegetation start and level of primary fruit set affect fruit quality
17-22.Views:185Thinning 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.
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Microsporogenesis of peach (Prunus persica L. Batsch) varieties
7-10.Views:261Bud dormancy during winter is a critical factor in peach production in Hungary. The yield is determined basically by the survival rate of flower buds during winter frosts and by their ability to develop normal floral organs. It is important to investigate the genetic basis of slow floral development during dormancy for the purpose of breeding peach varieties with better winter hardiness. The aim of the present research was to examine microsporogenesis in 14 peach varieties during three successive winters in a Hungarian germplasm collection and to study the effectiveness of this method in variety evaluation. There were significant differences in the dynamics of microsporogenesis both between the varieties and between the years. Of the varieties, ‘Mayfire', bred in California, possessed the quickest pollen development rate. The microsporogenesis of `Piroska', a Hungarian local variety, was the slowest. Rapid floral bud development was observed in `Aranycsillag', `Springcrest' and 'Venus'. A medium developmental rate was characteristic of `Babygold 6', Fairlane', `Michelini' and `Red June', while development was slow in 'Champion', 'Early Redhaven', `Redhaven', `Harko' and `Mariska'. Based on these results, the study of microsporogenesis represents a reliable method for the phenological description of peach varieties during dormancy. The application of this method makes it possible to identify varieties and landraces with slow flower bud development, suggesting better winter hardiness.