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The atmospherical drought as a decisive factor of yield in the main sour cherry varieties of Hungary
121-125.Views:228Atmospheric drought causes heavy diffi culties of water supply in most fruit species grown in Hungary, although the modern, intensive plantations are already equipped with irrigation. The use a dripping systems are widely applied, therefore nothing was done to avert the risk of atmospheric drought. In excessively dry seasons the reduction of yields is often due to atmospheric drought. Present study aims to utilise measured data of meteorological parameters (relative air humidity and temperature) to develop an index to characterise drought and measure its effect on fruit yield. Causes influencing yields are multiple. Phytosanitary problems are combined with defi cits of water supply. Water deficit of the soil is avoided by dripping irrigation, but the atmosphere is infl uenced by sprinklers only. Atmospherical drought increases the transpiration of the trees intensely and causes reduction of photosynthetic activity, consequently impairs the yield. Applying the index developed in a plantation of 6 sour cherry varieties grown in Hungary (Meteor, Nefris, Pándy, Újfehértói fürtös, Kántorjánosi, Debreceni bôtermô), we measured the specific yields (yield per volume of tree crown) during the period 1989–2011 using the meteorological database of the growing site. Additionally, other parameters characterising the drought are compared and searched for a method most reliable for judging the specific yielding capacity of sour cherry varieties. The results proved convincingly the utility of the index, especially for the varieties Pándy and Újfehértói fürtös. Comparison with other indices expressing the effects of drought revealed the superiority of our index, which will be applied in the future to express the risk of atmospheric drought.
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Possibilities of blossom and twig blight management in organic stone fruit production
103-105.Views:227In 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).
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Effects of weather characteristics on blooming dates in an apple gene bank plantation between 1984 and 2001
37-44.Views:240The aims of this paper was to investigate the flowering characteristic of apples and their relationship to meteorological parameters. The trees observed are grown at Ujfehert6, Eastern Hungary in the plantation of an assortment (gene bank) with 586 apple varieties. Each of the varieties were observed as for their dates of subsequent phenophases, the beginning of bloom, main bloom and the end of bloom over a period between 1984 and 2001. During this period the meteorological data-base keeps the following variables: daily means of temperature (°C), daily maximum temperature (°C), daily minimum temperature (°C), daily precipitation sums (mm), daily sums of sunny hours, daily means of the differences between the day-time and night-time temperatures (°C), average differences between temperatures of successive daily means (°C). Between the 90th and 147th day of the year over the 18 years of observation. The early blooming varieties start blooming at 10-21 April. The varieties of intermediate bloom start at the interval 20 April to 3 May, whereas the late blooming group start at 2-10 May. Among the meteorological variables of the former autumnal and hibernal periods, the hibernal maxima were the most active factor influencing the start of bloom in the subsequent spring.
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Relationship between several meteorological factors and phenological features of pear cultivars
67-73.Views:218The aim of this paper was to investigate the fl owering characteristic of apples and their relationship to meteorological parameters. The trees observed are grown at Újfehértó, Eastern Hungary in the plantation of an assortment (gene bank) with 586 apple varieties. Each of the varieties were observed as for their dates of subsequent phenophases, the beginning of bloom, main bloom and the end of bloom over a period between 1984 and 2001 during this period the meteorological data-base keeps the following variables: daily means of temperature (°C), daily maximum temperature (°C), daily minimum temperature (°C), daily precipitation sums (mm), daily sums of sunny hours, daily means of the differences between the day-time and night-time temperatures (°C), average differences between temperatures of successive daily means (°C). Between the 90th and 147th day of the year over the 18 years of observation. The early blooming varieties start blooming at 10–21April. The varieties of intermediate bloom start at the interval 20 April to 3 May, whereas the late blooming group start at 2–10 May. Among the meteorological variables of the former autumnal and hibernal periods, the hibernal maxima were the most active factor infl uencing the start of bloom in the subsequent spring.
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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:217The 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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Relations of phenometrical indices of apple fruits with weather variation in the assortment of varieties of an apple gene bank
115-120.Views:220The purpose of phenometry is to examine the measurable parameters of the plants in order to follow up the consequences of weather processes. We should fi nd the reasons, why the diameter of fruits grows larger in one season and smaller in the next. Variation may occur as a response to insuffi cient provision of water or nutrients, but also because of pathological effects and of extremely high or low temperatures, moreover, of extraordinary heavy fruit load. There are phenometrical characteristics, which consider the fi nal consequences (density of fl owers, fruits set, drop of fruits), whereas other parameters could be followed up (size, length and width of fruits) as the dynamic components of growth. The quantitative parameters of growth are functionally related to each other, where the weather conditions, soil humidity and nutrients are on the input side, thus it is possible to model the growth of fruits as a function of the environment. Initially, the relations between the main weather variables and the phenometrical data have to be cleared. In the present study, the interactions between the mentioned phenomena are presented and numerically defi ned.
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Some aspects of reduced disease management against Monilinia spp. in sour cherry production
50-53.Views:202The aim of this study was first to test the in vitro effeicacy of some fungicides against brown rot of sour cherry, and secondly to evaulate the effectiveness of reduced spray programmes against brown rot in integrated and organic sour cherry orchards. In vitro efficacy of 7 fungicides (Champion 50 WP, Kocide 2000, Nordox 75 WG, Olajos rézkén, Kumulus S, Rézkén, Rézoxiklorid) and another 6 fungicides (Score 25 EC, Efuzin 500 SC, Systane, Folicur Solo, Zato Plusz, Rovral) approved in organic and integrated production systems, respectively, were tested against brown rot of sour cherry. Altogether four spray programmes were performed i) standard integrated: sprays followed by forecasting systems during the season, ii) reduced integrated: sprays followed by forecasting systems but only 75% of the spray numbers used during the season-long spray programme, iii) standard oragnic: sprays applied every 7–14 days during the season and iv) reduced organic: 60% of the spray numbers used during the season-long spray programme. In vitro results showed that fungicides (with active ingredients of copper and sulphur) applied in organic production showed relatively high percent growth capacity of Monilinia fungus. Rézkén showed the highest and Kumilus S the lowest efficacy against brown rot. Fungicides applied in integrated production showed relatively low percent growth capacity of Monilinia fungus. Score 25 EC showed the highest and Rovral the lowest efficacy against brown rot. Field study showed that reduced spray programmes did not increase significantly brown rot incidence in the integrated field. However, brown rot incidence increased significanly (above 30%) in the reduced spray programme for the organic orchard.
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Effects of crop load on tree water use in apple (Malus x domestica Borkh.)
29-31.Views:128Sap flow rate measurements were carried out during two consecutive ('on' and 'off') years in an apple orchard cv. 'Florina' M.26 to analyse the effects of various crop load on tree water use. Sap flow rate was measured by thermal dissipation method in trunks of nine trees from June to the harvest. Crop load was between 0.2-9.0 fruits • cm -2 of trunk cross section area (equal to 0.5-35.0 fruits•m-2 of leaf area), trunk diameter varied between 4.7-8.7 cm.
Total leaf area was estimated by leaf counting or using shoot girth and leaf area relationship. In both years, fruit growth rate was determined by measuring diameter of 280 marked fruits with 7 days frequency. Fruit volume calculated as a function of fruit diameter based on a previously determined relationship.
Total leaf area of trees ranged from 4.4 to 19.5 m2 and it was closely related to trunk cross section area. At high crop load the fruit growth rate peaked in August with 0.51.tree-l.day-1 and the leaf area specific total fruit volume reached 61 m2 before the harvest.
There was a linear relationship between total leaf area and daily water use, while the leaf area specific water use was influenced by crop load rate. The relationship was described by piecewise linear regression with the breakpoint at crop load rate of 12 fruits•m2 of leaf area. At low crop load the slope of the fitted regression line was less than at high crop load rate.
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The tests of effectiveness of Frostbuster under excessive weather conditions in an apricot plantation
87-91.Views:287Frostbuster is a new system, engine and technology, developed to protect fruit plantations from the frost damage. In order to raise domestic experiences and measurements, experimental approach has been initiated to prove the utility of the system under excessively low temperature in the plantation of the Siófoki Gyümölcstermesztési Zrt (Fruit Growing Co. Siófok). The first opportunity ensued in the night of February 23-24, 2011, when the temperature sank to 12°C below zero. The question was to see whether we could prevent the drop of temperature by the frostbuster technique. The margin of an anticyclone staying on East Europe secured a stable condition to make tests. The only difference from the imaginable conditions of dangerous frosts was the heat keeping capacity of trees was weak, much inferior than compared with trees in full boom. As a consequence, the tree rows represented much lower heat-capacity and cooled down much quicker than blooming trees in springtime, i.e. their temperature was more variable. The other difference was, compared with an episode in spring that the hard frost lasted much longer than usually in spring. For testing the system, those conditions had even more advantage. Six meteorological stations helped us in measurement. Data-collectors were timed to 1 minute distances and the bulk of data proved to be beneficial for testing the Frostbuster. The results prove that the system is adequate to keep the temperature continuously higher than the surrounding field under excessively low temperatures. Further measurements are still needed to find the optimal solutions fitting to the growing site and its microclimate. Results presented offer a basis of further proofs.
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The effect of day and night temperatures on apple skin colour formation
21-25.Views:250The colour of fruits is considered to be an important quality indicator. Saleability greatly depends on how well covered the colour is of the specific type of fruits. It is a well-known phenomenon by growers that apples get nicer colours in one year while in other years the basically red and green colour cultivars can be differentiated only by morphological characteristic features. Cover colour is one of the phenometric variables and it is a well-known fact that significant differences can be experienced year by year. The experienced oscillation can be the cause of inappropriate water- and nutriment supply, however it can be the result of some kind of plant disease, extremely high or low temperature, setting rate above the average and outstanding fruit density. In the present examination it is postulated that the degree of cover colour is mostly influenced by day and night temperature. Therefore, our study aims to find out whether it is true or not. Cover colour belongs to those phenometric characteristic features, only the final value of which is taken into consideration; due to their nature of establishment or forming time it seems useless to follow closely the change in the time of vegetation. However, determining the start of colouring and knowing the dynamics of full colouring could carry very important information for growers. If it is possible to determine the curve describing the time change of colouring, we have a possibility to estimate it by means of enviroment variables. So it is also possible to model pigmentation in the future. Knowing this, colouring irrigation could be made more efficient in the future. For this, as a first step, it is inevitable to find out what the relationship is between the main meteorogical variables, namely day and night temperature and the difference between day and night temperature, and colour cover. In this study we summarize and show these interrelations.
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Spatial and temporal variation of extremely abundant maxima of precipitation in Hungary during the period between 1951 and 2010
107-114.Views:362The study deals with the accumulated database of 16 meteorological stations in Hungary during a period of 60 years. The purpose was to reveal the spatial and temporal structure of the appearance of extreme values in the daily distribution of data concerning precipitation. We strived to answer the question whether the frequency of incidences of daily maxima did they change or not during the 60 year-long period in the main growing regions of the country. It is demonstrated on geographical maps how the size and frequency of precipitation episodes ensued, and what are the typical traits of changes in intensity as well as in frequency of happenings projected according to their spatial and temporal distribution. From the point of view of fruit and vegetable growing, it is of prime interest what kind of frequency and intensity of changes occurred in precipitation. The temporal distribution of extremities though did not seem to change signifi cantly in some areas, but the recognition of changes may help conspicuously the planning and the choice between alternatives of species and varieties as well as technologies of horticultural managements for the long run. Extremely intense rains during a short time may cause erosion and stagnant water, thus we have to know what are the odds of risk. The temporary distribution of changes helps us to judge upon the reality of anxieties, which are expected according to the existence of trends. Seasonal or monthly distribution is visualised by maps, what is expected and what is accidental as for a decision in planning. The spatial distribution of coeffi cients of variation help us to decide what is the local chance of extreme happenings at different parts of the country and what is its coeffi cient of uncertainty. The risk of any undertaking dependent on conditions of weather could be expressed numerically by a coeffi cient of risk.