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The effect of climatic anomalies on the nutrient supply of fruit plantations (Minireview)
111-116.Views:276Climatic conditions play an important role in agricultural production. It has a profound influence on the growth, development and yields of a crop, incidence of pests and diseases, water needs and fertilizer requirements in terms of differences in nutrient mobilization due to water stresses. Nowadays, we have to know the dark side of the weather events because it is causing more and more problems and significant hazards to many horticultural regions in Hungary. The aim of this study is to explore the problems of nutrient uptake following climatic anomalies and response. These problems are: (i) water supply problems (water-stress); (ii) drought and frost as temperature strees. Reviewing the effects and nutrient disorders caused by climatic anomalies, the following statements can be taken:
- Nutrient demand of trees can be supplied only under even worse conditions.
- The most effective weapon against damage of climatic anomalies is preventative action.
- When developing a fruit orchard, three factors should be taken into consideration: "Location, Location, Location".
- Moreover, proper choice of cultivars, species and cultivation should provide further possibilities to avoid and moderate the effects of climatic anomalies.
- Fruit growing technologies especially nutrition should be corrected and adjusted to the climatic events as modifier factors.
- Urgent task of the near future is to correct and adjust the tested technologies of fruit growing according to these climatic events as modifier factors.
Optimal nutrient supply of trees decreases the sensitivity for unexpected climatic events. To solve these problems supplementary, foliar fertilization is recommended, which adjusted to phonological phases of trees.
Another solving is groundcover of soil means a potential opportunity to temper or even avoid climatic anomalies.
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Morphological and phenological properties of sour cherry varieties grown in Hungary and their inter-incompatibility relations
114-117.Views:220Regular observations and experiments were performed during a 14 year period on 6 sour cherry varieties. The morphological traits of leaves and fruits were compared, and the phenology of blooming as well as of ripening dates served to start an estimation of the possibilities of mutual pollination and the planning of harvest operations. Experiments involved obligate autogamy, artificially controlled allogamy and open pollination in order to reveal self-fertility, self-sterility or inter-incompatibility relations.
The varietal characters represent, each, different values in the distinction of the items, because of their intra-varietal variability. From that point of view, the most reliable are the data of blooming and ripening time, fruit size and the fertility relations.
Inter-incompatibility was observed between the group of self-fertile, "Pándy type" varieties (`Újfehértói fürtös’, ‘Debreceni bőtermő’, ‘Kántorjánosi’) on one side and the selection of Pándy 7', a self-sterile variety on the other side. Unilateral incompatibility has been detected within the former group of new, self-fertile varieties, the combinations: (`Újfehértói fürtös’ x ‘Debreceni bőtermő’ as well as `Újfehértói fürtös’ x Kántorjánosi’.
Our results prove the close kinship between those three new varieties and the original Pándy variety on the base of being highly similar in their morphology and also of the fact of their inter-incompatibility, though unilateral.
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Economic figures of apple production at national level of Hungary
103-105.Views:314Apple is the most important fruit in Hungary, despite of that, it is a paradox that during the last years, apple growing was the most unsuccessful enterprise among the prosperous ones in the country. The real cause of regression was unequivocally the low price, which could be obtained and the inadequate structure of apple varieties. A heavy problem is still the overweight of the quality doomed to supplying the processing industry instead to the fresh consumption. In order to improve the conditions, we aimed the economic analysis of the five year long period, 2005-2009, to trace the changes involving values and costs of production, income and all conditions combined with this activity. The data presented in the paper are means of a heterogeneous population of values, which cannot be utilised for immediate use in management, but they may reveal the challenges and tendencies of that branch in economics.
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Acceptance of artificial nesting sites by pollinating mason bees in commercial fruit plantations (Hymenoptera, Megachilidae: mixed Osmia cornuta and O. rufa population)
43-46.Views:305During a four yeas long experiment a simple bee shelterswas found to be a propermethod to increase the size ofmixed natural populations of the early season Osmia cornuta and O. rufa under practical farm conditions. Instead of the number of pesticide applications the earliness of the flowering of the fruit species in the orchards was found to be themost important factor in the rate of acceptance of reed as nestingmediumby Osmias in the bee shelter. This relationship was negative and highly significant (r = –0.829, p<0.001). This means that much higher acceptance of artificial nestingmedia in bee shelters and consequentlymuch higher population increase of the two early seasonmason bee species can be expected in orchards with early than with late flowering fruit species. Mixed orchards or early flowering orchards surrounded by other orchards falling in bloom later consecutively may also be much favourable to mason bees because they can find continuous food (pollen) supply there for a much longer time during their period of activity than in orchards planted with a single fruit species and being apart from orchards of other fruit species.
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Fruit drop: II. Biological background of flower and fruit drop
103-108.Views:378The most important components of fruit drop are: the rootstock, the combination of polliniser varieties, the conditions depending of nutrition, the extent and timing of the administration of fertilisers, the moments of water stress and the timing of agrotechnical interventions. Further adversities may appear as flushes of heat and drought, the rainy spring weather during the blooming period as well as the excessive hot, cool or windy weather impairing pollination, moreover, the appearance of diseases and pests all influence the fate of flowers of growing and become ripe fruits. As generally maintained, dry springs are causing severe fruit drop.
In analysing the endogenous and environmental causes of drop of the generative organs (flowers and fruits), the model of leaf abscission has been used, as a study of the excised, well defined abscission zone (AZ) seemed to be an adequate approach to the question. Comparing the effects active in the abscission of fruit with those of the excised leaf stem differences are observed as well as analogies between the anatomy and the accumulation of ethylene in the respective abscission tissues.
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Effect of boron nutrition on nutrient uptake and fruit quality of tart cherry in Eastern Hungary
45-48.Views:286Effect of the foliar boron (B) application on nutrient uptake and fruit quality of tart cherry (Prunus cerasus L.) was investigated from 2008 to 2009 on mature four favourite Hungarian tart cherry cultivars like ‘Oblacsinszka’, ‘Érdi bôtermő’, ‘Újfehértói fürtös’ and ‘Petri’. Tart cherry trees grown in Eastern Hungary (Újfehértó) on an acidic sandy soil with low B content. Trees were treated with B by foliar application (0.5% B) at full bloom and untreated with B served as a control. B sprays strongly affected on B content of inflorescences. However, B sprays had no consistent effect on summer leaf B status. In our experiment stronger year effect was observed at leaf B status than flower B status. The effectiveness of early spring boron applications are limited and mostly affected the flower B status only. Moreover, treatments had inconsistent effect on studied fruit inner parameters. Monosaccharides, vitamin C and organic acid contents of sour cherry were stronger affected by cultivars than applied treatments.
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Assessment of apple varieties based on consumer judgement on their fruits of organic production for fresh consumption
87-90.Views:282The lack of information is often cause of the insufficiency of attributes being developed and appears on the new commodity characterising its utility. Neither own nor other information is presented. For improving this handicap, we endeavoured to praise apple products grown by biological methods and explain their properties as taste, skin, colour, consistency, and size. In addition, we explore the relation between general impression and the individual properties. The scrutiny starts with collecting of primary data on 9 samples taken from biologically grown apple varieties kept over 60–90 days in a store and offered to the consumers. The test is based on an organoleptic assessment (records are registered in a questionnary). The individual judgements are processed and coefficients of correlation between the traits (taste, skin, size, colour) calculated. The validity of the mathematically proved relations is considered to be decisive judging the preferences in consumption of fruits.
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Bee pollination and association of apricot varieties
20-24.Views:256Apricot yields are highly variable according to the season. The variation is caused mainly by the adversities during the critical processes of floral biology, i.e. blooming and fertilisation. On the basis of information concerning blooming time and mutual compatibility relations of apricot varieties a system of securing regular and adequate yields has been developed.
Winter frosts of the continental type are well tolerated by most of the apricots, however, after the end of rest period, flower buds are loosing frost tolerance, 'rapidly.
Being one of the fruit species blooming earliest during the early spring, apricot start to bloom in Hungary around the end of March or early April as a mean of many years, but it also happened, exceptionally that apricot started to bloom at February 20 (at Letenye South Hungary). The early season, exposes the floral organs to frost injuries. As a consequence, apricot orchards on the Great Plain produce low yields in 3 years, intermediate yields in other 3 years out of a ten-year-period.
Moreover, weather conditions during the blooming period are often unfavourable for pollination. Cool, windy and rainy weather prevents the flight of insects and on the other hand, warm spells shorten the blooming process, nectarines and stigmata get dry and the female gametes loose viability before effective pollination occurres.
The fertility of individual cultivars are meeting different obstacles. Apricot cultivars differ greatly in the rate of flowers bearing underdeveloped pistils, which may attain even 60% (e.g. Orangered). New commercial cultivars are often self-incompatible. Local varieties of that type in Hungary are the „óriás" varieties (e.g. Ceglédi óriás, Szegedi mammut), and the new hybrid Ceglédi Piroska. Many of the cultivars are variable in their self-fertility (partially self-fertile): Budapest, Harmat, Korai piros, Mandulakajszi.
Inter-incompatibility is also known in apricots. The „óriás " varieties do not fertilise each other. During the growth of fruits, cool spells (2-4 °C) caused severe fruit shed in Ceglédi óriás.
Apricot flowers produce pollen and nectar at average rates related to other fruit species, thus bees are attracted sufficiently. Bee visits are very variable according to growing site and season. Most of the bees are pollen gatherers but sometimes nectar suckers are in majority. Bee pollination is necessary not only for the self-incompatible varieties but also to enhance the yield of self-fertile varieties.
Taking the blooming and fertility relations of the cultivars into account, plantations should not exceed two rows to a particular self-incompatible varieties, and possibly two different polliniser varieties are suggested to be planted as flanking the block in question.
In commercial plantations 2 to 4 bee colonies per hectare are proposed to move for the whole blooming period.
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The use of rootstocks for European (Prunus domestica) and for Japanese (Prunus salicina) plums (review)
7-13.Views:470The worldwide tendency to increase the intensity of fruit growing technologies prefers generally for every fruit species rootstocks with week or mediocre vigour. From this viewpoint, the use of rootstocks for plums are rather unilateral in Hungary, where 95–99% of plum plantations are grafted on mirobalan seedlings (P. cerasifera v. mirobalana). The score of plum rootstocks abroad is much more diversified. The present study summarises the respective knowledge referring to the literature available.
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Characterization of sunburn damage to apple fruits and leaves
15-20.Views:672The specific conditions of the formation of three different types of sunburn (sunburn browning, sunburn necrosis, and photooxidative sunburn) have been recently characterized on apple fruit. However, no information is still available on leaf damage. Therefore, the aims of this study were i) to extend the knowledge on fruit damage, ii) characterize leaf damage and iii) find relationship between fruit and leaf damage. The observations were made on 586 apple accessions in a gene bank orchard located in Hungary. The incidence of the three different types of fruit symptoms were recorded and based on the visual symptoms, two different types of leaf sunburn (sunburn yellowing and sunburn necrosis) were characterized. The most frequent type of fruit sunburn observed was sunburn browning. Photooxidative sunburn was found for less number of accessions, and only some accessions were affected by sunburn necrosis. Fruit were far more susceptible than leaves; (>60%) of the examined accessions were affected by fruit damage and (<3%) by leaf damage. Although a large number of accessions were affected, the percentage of fruit damaged within accessions was not that excessive; ~6% of the fruit assessed showed the symptoms of sunburn browning. Significantly fewer fruit were damaged by sunburn necrosis (~1%) or photooxidative sunburn (~1.4%) than sunburn browning. The percentage of leaves damaged within accessions were simlarly very low (~1%). Close relationship between fruit and leaf damage was found. Accesions with relatively heavily sunburned leaves usually had severe fruit damage as well. Leaves showing sunburn symptoms were usually closely located around those fruit which were sunburned severely. Leaf damage of sunburn was found on spur leaves in a great majority of the accessions damaged, shoot leaves did not seem to be susceptible to sunburn.
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Comparative study of effects of a complex fertilizer and a biostimulator on macroelement content of leaf and fruit quality on sweet cherry (Prunus avium)
91-94.Views:283In 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 and 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.
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Association of European plum varieties in the orchards
21-24.Views:282The flowering phenology, blooming time and inter-fertility relations of 63 European plum varieties has been studied at growing sites with different ecological conditions during a 10 year long period. The purpose was to develop a system of variety combinations which approaches an optimum in fertility as long as inter-fertility relations will cease to be a limiting factor of yield. According to their blooming time, varieties are assigned to 5 groups: very early, early, medium, late and very late. As for their fertility relations, four groups are formed: self-sterile (0%), partially self-fertile (0.1 to 10 %), self-fertile (10.1 to 20 %) and highly self-fertile (more than 20 % fruit set with self pollination). The four categories of fruit set at free pollination are also relevant to the grower: low (less than 10 %), medium (10 to 20 %), high (20 to 40 %) and very high (more than 40 % fruit set).
By artificial cross pollination, one combination Cacanska najbolja x Stanley proved to be mutually inter-incompatible. Blocks planted to a single self-sterile variety flanking a pollinizer variety proved the spacial distribution of the pollen. The reduction in fruit set was already apparent in the second row away from the pollinizer trees. In a large plantation, without bee hives, relatively low yield was stated on self-sterile trees even close to the pollinizer.
In the case of self-sterile and partially self-fertile varieties, a combination of three varieties is recommended. The blooming period of the pollinizer variety should overlap the period of the self-sterile variety at least by 70 %, and the distance should not exceed 15 to 20 meters. Association of self-fertile varieties may also enhance the productivity of the trees. In that case an overlap of 50 % in blooming time and a maximum distance between the varieties of 30 to 40 meters will be sufficient.
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Prevention and protection technologies – How do the growers get ready for climate change?
67-69.Views:358Within the sector of fruit growing, climate change related tasks cover a rather wide range of activities. According to what is claimed by the literature, all decisions impacting the sector should be made conformably with climate change in order to advance an increase in yield security. This, regardless of the impacts of climate change, is also one of the key questions in fruit growing. Regarding protection against extreme weather events, in addition to technological and technical elements, the level of importance assumed by farmers for the abovementioned protection techniques as well as the type and extent they intend to use of this in practice are also worth of studying. This ongoing research beginning in 2009 mainly focuses on studying the opinions of fruit farmers making up the target group for this analysis. The questionnaire survey primarily intends to study their knowledge on the definition of climate change as reactivity to unfavourable weather events occurring in the growing. The study aims at providing a realistic view on the fruit-farmers’ knowledge on climate change and on how technological elements, new technical solutions applicable to mitigate damage are used during production.
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Effects of self and cross pollination on fruit set and fruit quality of sour cherry cultivars
31-36.Views:376An experiment conducted using factorial based on randomized completely block design during 2005 and 2006. Flowers of Érdi bőtermő, Érdi jubileum and Cigány meggy before anthesis and in balloon stages were isolated with paper bags from guest pollens and pollinated in appropriate time. The averages of final fruit set showed the advantage of open pollination (14.6% fruit set) in compare with artificial self pollination (13.0% fruit set) and natural self pollination (4.4% fruit set). Siah mashhad sweet cherry cultivar with more than 70% overlap of flowering and 9.8% fruit set in 2005 and 17.9% in 2006 was the best among applied pollinisers for Érdi bôtermô sour cherry cultivar.Also, Siah mashhad sweet cherry with more than 50%overlap of flowering time and 25.8%fruit set was the best polliniser for Cigány megg. Among the pollinisers, Siah mashhad was the best for Érdi jubileum with more than 50% overlap and 15.22% fruit set. Meanwhile, pollens of Siah mashhad caused the increase of fruit size in Cigány meggy cultivar. phenomenon. Pollens of Siah mashhad caused reduction in total soluble solids of Érdi bôtermô fruits, however, it does not have any significant effect on the acid rate of fruits.
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Technologies developed to avoid frost damages caused by late frost during bloom in the fruit growing regions of Siófok and Debrecen
99-105.Views:404The aim of the study was to fi nd out which of the methods used to avoid damages of late frosts would be the most effective for the fruit growing practice. Three technologies have been tested in the regions of Siófok and Debrecen-Pallag. The antifrost irrigation proved to be the most advantageous. For that purpose microjet sprayers are used, which are thrifty and do not need for that purpose large containers. With the aim to secure an even distribution of water, the sprayers are distributed on three levels: above and inside of the crown as well as on the level of trunks. On a large scale, a single microjet above the crown level would be suffi cient. By means of a detailed analysis served to set the optimum intervals between spraying phases: with each 15, 10, 5 and 3 minutes during half a minute. The synchronous presence of water and ice below the freezing point, the released freezing heat plus the water used much above the freezing point (9–10 °C) altogether maintains the temperature above around 0°C near the fl owers or growing fruitlets, meanwhile, the surrounding air cools down to –8 °C. The effectiveness of the generally used anti-frost would be increased substantially by the former application of cooling irrigation, which delays the blooming date. The Frostbuster represents a new technology developed for the same purpose of frost defence. It uses butane burning and produces high (80-90°C) temperature with a strong blast of air. On the protected area sensors have been distributed for measuring temperature and relative humidity. The means of the measurements proved a rise of temperature, which was suffi cient to save the fruit trees until the difference is less than –3–3.5 °C. Our analyses stated that paraffi n candles avert the frost until –4 °C. Its success depends largely on the intensity of air movements. A small wind would be enough to frustrate the effect. The results show clearly the utility of Frostbuster and paraffi n candle combined is approved.
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The effect of cooling irrigation on the blooming dynamic of plum
57-59.Views:309The objective of the present study is to explore the effect of cooling irrigation (aspersion) on the beginning of bloom and on the micro-climate of the plantation. The results show that the water sprayed in the orchard by micro-jet influenced decisively the temperature of the plantation. At higher temperatures (around 20 °C), the drop of temperature may attain 5–7 °C. A low relative humidity of the air may increase the relative effect, The frequent repetition (20 minute intervals) may keep the temperature low also in the buds. The beginning of bloom may delayed for more than ten days. The dynamics of blooming was characterised by a logistic curve in the treated as well as in the control plot. In the treated plot, the curve was steeper than in the control in spite of equal temperatures measured in the plots. Under our (Hungarian) climatic conditions, the method is successfully used to delay blooming dates. The main result is the diminution of the frost damage in the spring and the security of yield. The costs and water requirement should be calculated later.
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Relationship beetwen the phenological features of pear cultivars and the main meteorological parameters in a gene bank with 555 pear
59-63.Views:229The trees observed are grown at Ujfehert6, Eastern Hungary in a gene bank with 555 pear cultivars. Each of the cultivars was monitored for its dates of: the beginning of bloom, main bloom and the end of bloom and ripe phenophasis separately between I 984 and 2002. We analyzed the statistical features, frequency, distribution of these phenophasis and its' correlation the meteorological variables bet ween the interval. During this period the meteorological database recorded the following variables: daily mean temperature (°C), daily maximum temperature (0C), daily mini m um temperature (0C), daily precipitation (mm), daily hours of bright sunshine, daily means or the differences between the day-time and night-time temperatures (0C). For the analysis of data the cultivars have been grouped according to dates of maturity, blooming period as well as types of the seasons. Groups of maturity dates: summer ripe, autumnal ripening, winter ripe cultivars. Groups of blooming dates: early blooming, intermediate blooming, late blooming cultivars. At all the separated groups we analyzed the relationship between phenophasis and meteorological variables. During the 18 years of observation , the early blooming cultivars started blooming on 10-21 April, those of intermediate bloom date started flowering bet ween 20 April and 3 May, whereas the late blooming group started on 2- 10 May. Among the meteorological variables of the former autumn and winter periods, the winter maxima were the most active factor influencing the start dates of bloom in the subsequent spring. For the research of fruit growing-weather relationships we used simple, well known statistical methods, correlation and regression analysis. We used the SPSS 1 1.0 software for the linear regression fitting and for calculation of dispersions as well. The 1ables made by Excel programme.
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Self fertility of pear varieties conditioned by natural self pollination (autogamy)
110-113.Views:287Authors studied the autofertility depending on natural self pollination (autogamy) in 59 pear cultivars during 4 seasons at three locations with different ecological conditions (Helvetia, Kecskemet-Kisfai, Keszthely). The aim of the experiments was to determine the autogamous tendencies of varieties hitherto unexplored in the Hungarien gene bank, or to check data found in the literature. A total of 42616 isolated pear flowers produced 1.2% fruits with at least one viable seed in each. The 59 varieties observed did not set fruit by autogamy on either of the three sites during the four years of the study. The triploid (3n=51) varieties were entirely self-sterile. According to the highest autogamous fruit set, during the experimental period, the varieties have been assigned to four groups: (1) Entirely auto-incompatible (0% fruit set), (2) auto-incompatible (0.1 to 0.9%), slightly self fertile (1.1 to 5%) and (4) self fertile (5.1 to 10%). According to the number of viable seeds per fruit resulting from autogamy, the varieties are assigned to three groups as (1) low seed content (less than 3 seeds per fruit), medium (3.1 to 5) and (3) high (more than 5 seeds). Thus, the assessment of the number of seeds per fruit resulting from autogamy is indispensable as a proof of the absence of parthenocarpy.
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Economic aspects of applying hail protection nets in apple plantations
99-101.Views:238The up to date intense apple growing in Hungary is capable to produce yearly about 500-1000 thousand Ft/ha income, which means that the investment of 4 000–5 000 thousand Ft is returned by producing 10-20% net income. The economic balance may, however, be upset by the damage caused by hail, quantitative and qualitative, with an apparently increasing frequency experienced in each third or fourth year. Estimates prove that each hail causing 50% damage may reduces the income proportionately to the capital by 1.5–2.0 percent points, which means a serious threat for the economy of apple production. According to calculations, a plantation producing 30–40 t/ha yields would not be able to raise incomes compensating the investment of 7.0–10.0 million Ft/ha, let alone the frequencies of hail damages. Consequently, 50–60 t/ha yields are needed to become successful, and in planning of new plantations those high yields are aimed with hail nets. An additional difficulty is represented by a lack of financial resources to install hail protection nets.
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Evaluation of sour cherry varieties grown with environmental technology
39-41.Views:592The evaluation of a produce is an important moment of predicting its success on the market. The general impression, which is decisive, when a consumer chooses to purchase the commodity, should be interpreted in more objective, measurable terms. Primary data have been collected on fresh fruits derived from different growing technologies by organoleptic tests and the data filled up in the forms are processed with correlation analysis. The components were: taste, aroma, flesh firmness. The coefficients of correlation showed that the rest of characters as the appearance, juiciness, and the sugar/acid ratio.
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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:225The 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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Effect of over tree cooling irrigation on ‘Bosc’ pear orchards microclimate
153-156.Views:382Irrigation in some countries is a horticultural practice mainly used only to supply water. At the same time the use of microsprinklers have a powerful infl uence on the changes of temperature in orchards. When the air’s temperature is high (about 20 °C or higher) the evaporative cooling irrigation signifi cantly decreases the plants’ surface temperature and air temperature. The cooling effect is stronger when the air is dryer. By using cooling irrigation regularly, canopy temperature can be decreased so that the beginning of blooming can be delayed. Also if the blooming is early and frost probability is high, serious damages can happen in orchards. The benefi cial effect of cooling irrigation is the temperature reduction and frost protection. In March 2010, one month earlier than the expected blooming an irrigation system was established to produce anti-frost treatment and regulate the micro-climate of a Bosc pear orchard which belongs to the University of Debrecen (Hungary). The objective of sprinklers was to cool the air by increasing water evaporation and relative humidity. The position of the micro-sprinklers was planned in three levels (around the tree trunks, a few cm near to the soil surface, in the crown region and above the crown, a half meter higher). The results showed that the water sprayed in the orchard by micro-jets infl uenced decisively the temperature of the plantation. At higher temperatures (around 20 °C), the drop of temperature may attain 5–7 °C. A low relative humidity of the air may increase the relative effect. When water was applied at intervals of 15 minutes for ten times a day from 8 am to 18 pm, the air, fl owers and bud’s surface temperature could be kept low. At certain days when the temperature was higher than 10 °C, irrigation was used at night time in similar 15 minutes intervals, from 18 pm and 6 am. The beginning of bloom could be delayed for more than ten days. The Bosc pear variety blooming dynamics was characterized by a logistic curve in the treated as well as in the control plot. In the treated plot, the curve was steeper than in the control one in spite of the equal temperatures measured in the plots. Under Hungarian climatic conditions, the method was successfully used to delay blooming dates. The main result was the diminution of the frost damage in the spring that assured pears yields.
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Importance of boron in fruit nutrition
39-44.Views:378Boron (B) is an essential micronutrient in plants especially in fruits. Despite of this fact there are very few information about its application, uptake and symptoms in Hungarian fruit growing sector. Nowadays we should consider the effects of weather conditions on soil B availability increasingly according to the climatic anomalies. Identifying of internal and external symptoms of plant parts (leaf, fruit) is help for growers to recognize the deficiency and excess symptoms in time. Methods and application rates of boron fertilization provide further information for growers to achieve qualify-oriented fruit growing among Hungarian conditions. The aim of this minireview is to focus on the importance of boron in fruit nutrition.
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Sunburn incidence of apples is affected by rootstocks and fruit position within the canopy but not by fruit position on the cluster
45-51.Views:278Authors investigated sunburn incidence of apples on the combinations of three different growth inducing rootstocks (M.9,MM.106 and seedling) and five varieties (‘Smoothee’, ‘Golden Reinders’, ‘Granny Smith’, ‘Gloster’ and ‘Jonagold Jonica’). Symptoms were classified as sunburn browning, sunburn necrosis and photooxidative sunburn. The frequency of symptoms was recorded at various parts of the canopy (N, E,W, S, and lower canopy, upper canopy) and on the cluster (terminal, lateral). Cultivar susceptibility varied between 0.30 and 5.65% on M.9 rootstock, ‘Granny Smith’ seemed to be the most susceptible cultivar whereas relatively low percentage of damaged fruit was observed for ‘Gloster’. On MM.106 and seedling rootstocks, damage level was significantly lower than on M.9. Remarkable differences were not observed in the share of the three sunburn types between cultivars. The most common symptom observed was sunburn browning. Far less fruit was affected by sunburn necrosis and photooxidative sunburn. Photooxidative sunburn symptoms were not found on ‘Granny Smith’ and ‘Gloster’ fruits on MM.106 rootstock. Latter cultivar did not show sunburn necrosis symptoms either. With increasing growing vigor of the rootstocks the share of sunburn browning increased. Fruits with sunburn symptoms were found in a great majority on theW quadrant of the trees. This was true for all cultivars. Remarkable differences in the location within the canopy of affected fruits between the three types of sunburn were not observed. Specific distribution of sunburned fruit was observed along the vertical axis of the canopy, too. Most of the damaged fruit were found in the upper canopy. This is particularly true for trees on vigorous stocks such as MM.106 and seedling. On M.9 rootstock, depending on cultivars 5.9 to 38.9% of sunburned fruit was located in the lower canopy. Most common symptom in the lower canopy was the sunburn browning, however symptoms of sunburn necrosis were not found at lower canopy level. Low rate of photooxidative sunburn was observed such lower canopy conditions. Sunburn incidence was very similar on king or side fruit. Significant differences were not found in the share of each sunburn types between fruit positions on the cluster. This was not influenced by rootstocks either.
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Floral biology of hazelnut (Review article)
7-19.Views:302Floral biology of hazelnut (Review article)