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The role of meteorological variables of blossoming and ripening within the tendency of qualitative indexes of sour cherry
7-10.Views:262We analyzed the relationship to sour cherry quality parameters of average temperature, maximum temperature, minimum
temperature, night and day-time temperature, precipitation and climatic water balance variables. Three cultivars of sour cherry were included
in the selection: “Debreceni bôtermô”, “Kántorjánosi”, and “Újfehértói fürtös”.We conducted regression analyzes on the three varieties, but
present only those that proved to be the best fit.We couldn’t find any significant differences in the weather tolerance of the varieties. The data
base of sour cherry quality parameters covers the 1998 to 2008 intervals. The researched parameters were the following: dry matter content
(%), sugar content (%), C-vitamin (mg), total acid content (%). Maximum temperature, the difference of night and day-time temperature and
minimum temperature all have a significant correlation with the investigated quality parameters of sour cherry. Minimum temperature shows
a quadratic relationship with sugar content, while night and day-time temperature differences show the same with dry matter content. The
other weather parameters had a linear correlation with the quality parameters of sour cherry. The research results show that an increasing
amount of precipitation causes decreasing tendency in total acid content of sour cherry, so that increasing temperature has a positive influence
on total acid content. Big differences in night and day-time temperature also has positive effects on the dry matter and sugar content of sour
cherry while the amount of precipitation has a negative effect. High minimum temperatures cause decreasing sugar content respiratory energy
losses are significant if dawn temperatures do not drop considerably.A more favourable climatic water balance has a positive effect on vitamin
C content in cases of a large negative water balance, vitamin C content is generally low. -
Connection of fertilization conditions of sour cherry and meteorological parameters
17-21.Views:329Our analyses showed that the degree of free fertilization is mostly influenced by maximum temperature and sunshine duration.We found that free fertilization ratio increases with higher daily maximum temperatures; similar results characterise sunshine duration as well, namely we observed higher free fertilization ratio at higher sunshine duration values. Total amount of precipitation during the period between blossoming and maturity and the difference between the average daytime and night temperatures have an important role in the tendency of maturity time. Photosynthesis and respiration are essentially significant in the development of biological systems. These two processes are mostly regulated by the daytime and night temperatures. Therefore, it is not surprising that if the difference between daytime and night temperatures is large, it means intensive photosynthesis and a low degree of respiratory loss. Under these conditions intensive development and ripening can take place; however, in case of a low temperature difference intensive respiration slows down the process of development. Duration of ripening is also significantly influenced by the amount of precipitation of the period between blossoming and maturity.Abundant precipitation slows down the process of ripening, while dry weather accelerates it. Self-fertilization takes place in a space isolated from the environment. In spite of that, we found that effectiveness of self-pollination significantly depends on the meteorological conditions. Degree of self-fertilization is influenced directly by temperature and indirectly by other climatic parameters. We found a significant connection between the values of maximum and minimum temperatures during blossoming and the ratio of self-fertilization. Increase of maximum temperature reduces the effectiveness of self-pollination.A 1 °C increase of maximum temperature reduces self-fertilization ratio by 0,6%. In the case of minimum temperature we can state that the morning minimum temperature of 7,5–8,5°C is the most favourable. If minimum temperatures are under 4 °C or above 12 °C, self-fertilization ratio reduces to the quarter of the value characteristic at 8 °C. We believe that the effectiveness of self-fertilization can be improved considerably by the rational placement of isolator bags within the crown area, avoiding their placement to the external, western crown surface.
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Relation of sour cherry blooming dynamics and meteorological variables
17-23.Views:272The aim of our research was to identify the role of weather parameters in the development of the start date and length of blooming. In order to achieve this, we examined how meteorological conditions of a particular year influence the start date and length of blooming in different years (dry, wet, cool, hot, sunny, cloudy). The meteorological parameters were the following: maximum temperature, minimum temperature, average temperature, precipitation, length of sunlight, difference of daytime and nightime temperatures, potential evaporation-PET, Huglin-index,Winkler-index, climatic water balance which can be calculated as a difference of precipitation and potential evaporation. In this study we wanted to find out whether early start of blooming results in a longer blooming period or if there is a generally faster blooming period when blooming starts later. Based on the results we can say that early start of blooming resulted in extended blooming period for three sour cherry varieties at the examined production sites. The start of blooming showed the closest relation with the difference of average daytime and nightime temperatures of the 30-day period prior to blooming. Significant relation was also detected with the thermic indexes as well as with maximum temperatures, climatic water balance and the degree of potential evaporation.We examined how weather 30 days prior and during blooming influenced the length of phases. Results showed that precipitation prior and during blooming is in significant relation with the length of blooming. We detected significant relation between daytime and nightime temperature differences and the length of blooming. The nature of the relation indicates that blooming periods were shorter in case of increasing temperature differences.We found that shorter blooming lengths occurred when maximum temperatures averaged between 13.5–14.5 ºC 30 days prior to blooming when examining the relation between blooming length and maximum temperature. If the average of maximum temperatures was below 13 ºC or exceeded 15 ºC during this period, then we could calculate with a blooming period longer than ten days. We proved that little precipitation and high temperature accelerates physiological processes, therefore we could calculate with an accelerated blooming and shorter blooming period.
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Reproductive biology of Duranta repens L. (Verbenaceae) in relation to its environment
51-55.Views:253Impact of environmental changes (temperature and RH) on reproductive biology in Duranta repens (Verbenaceae) growing at ten different sites of Agra was studied. It flowers throughout the year, with optimum flowering in September. The flowers are arranged in loose clusters on terminal or axillary racemes. They are either blue or lavender in colour, hermaphrodite, actinomorphic and complete. The plants exhibit floral polymorphism (increase and decrease in number of petals and stamens) and considerable variation in extent of pollen fertility, floral density, insect pollinators and fruit-set percentage. The changes in temperature and relative humidity during the entire flowering period, was found associated with the variation in floral structure, pollen fertility and fruit-set percentage. Based on the percentage of fruit-set during different seasons of a year, there were three distinct periods, namely maximum, moderate and minimum periods. The present paper deals with the comparative view of reproductive biology of this ornamental plant in these periods. During the months of August—November when temperature ranges between 13.7-36.6 °C and RH between 79-89% the plant exhibits maximum fruit-set percentage (68-85%). This was associated with maximum flowering, increase in floral size, and increase in visitation rates of pollinators and higher degree of pollen fertility. On the other hand, with temperature reaching to the maximum (15.1-41.5 °C) and reduction in RH (14.1-41.3%), the percentage of fruit-set was reduced to the minimum (21-30%). During this period, number of flowers/plant, floral size, pollen fertility, visitation rates of pollinators were reduced to the minimum. During this period floral polymorphism was also 'recorded.
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Influence of soaking periods and temperatures on germination and respiration of pea seeds
69-71.Views:268Samples of 50 wrinkled-seeded pea (Piston sativum cv. ‘Farida') were soaked for 0.5, 1, 4, 8, 24, 48 and 72 hours at temperature of 5, 10, 15 and 20 °C in distilled water before germination. Water absorption, percent of germination, vigorous seedlings and dry weight of normal seedlings were assessed after 8 days. Respiration of short and long seedlings were checked by IRGA, LI-COR 6200 photosynthesis system. Most plants had more or less respiration but some of them already had photosynthesis. Differences in the amount of water absorbed were evident after one hour, only. Water amount was increased by increasing soaking temperatures and times. The maximum was achieved after 24 hours. Normal germination percent was not improved at any soaking time and temperature combinations but it was significantly declined at 10 °C with soaking time combinations and at 20 °C for 72 hours. The seedling vigour values were not very different at the higher soaking temperatures, but the treatments at 20 °C temperature with 8 and 24 hour soaking periods are proved to be optimal for seedling vigour. At the low soaking temperature the increase of the soaking period influenced the seedling vigour. Reduction of dry weight percent was noticeable by any soaking time related to temperature and compared with the control.
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A model of full bloom starting date of some white Vitis vinifera L. varieties grown in Helvecia
21-25.Views:182Grapevine bloom happens between end of May and the middle of June in Hungary. However, climate change in the past decades and the occurring weather anomalies can modi fy this date to a diverse degree. Among the weather factors, the bloom starting dates of grapevine depend mostly on temperature and relative humidity of air. There can be significant differences between North American and East Asian grapevine varieties, and of course, the early and late ripening varieties. ln this approach we investigated the starting dates of bloom between 2000 and 2004 for grapevine varieties grown in Helvecia, as well as the effectiveness of a temperature sum model. The model is based on the widely accepted cumulated heat sum concept, and the optimization was made for the least standard deviation in days as well as on the least average absolute deviation in days and on the least maximum deviation in days. The model is connected directly to a similar model for the budburst date of the same plantings (Hlaszny & ladanyi, 2009). We set the optimum lower base temperature to I 0.45 °C and the upper base temperature to 26 °C. The absolute values of the differences between the observations and the model estimations move between one and six days with an average of 1.81 days
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Effects of weather characteristics on blooming dates in an apple gene bank plantation between 1984 and 2001
37-44.Views:249The 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 apple cultivars
13-19.Views:247The trees observed are grown at Ofeherto, Eastern Hungary in the plantation of an assortment (gene bank) with 586 apple cultivars. Each of the cultivars 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 cultivars start blooming at 10-21April. The cultivars 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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Heat waves in Hungarian plant production
113-118.Views:193A 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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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: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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Relations of phenometrical indices of apple fruits with weather variation in the assortment of varieties of an apple gene bank
115-120.Views:230The 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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Simultaneousness of reproductive organs of sour cherry cultivars adaptable to Iranian climatic condition
25-31.Views:253Observations were made on simultaneousness of pollen shedding and stigma viability ratio, to clarify the phenology of reproductive organs of nine economically important sour cherry (Prunus cerasus L.) cultivars (‘Érdi bôtermô‘, ‘Debreceni bőtermő‘, ‘Csengődi‘, ‘Kántorjánosi 3‘, ‘Újfehértói fürtös‘, ‘Petri‘, ‘Eva‘, ‘Oblascinszka‘, and ‘Pándy 279’). The main aim was investigation the possible influence of environmental cues in timing and development of phenophases and also responses of different cultivars to seasonal cues. Likely effects of climatic changes on phenological development patterns were also considered. Results showed important aspects of the reproductive biology of sour cherry flowers. The amplitude of the phenophase “beginning of blossoming” between cultivars did not exceed 6 days. There is a maximum 3 day difference in the blooming length of different directions in each cultivar. ‘Pándy 279‘ showed high variability when the position of flowers changed on the tree shoots. ‘Újfehértói fürtös‘ was stable in all four directions of the tree. The pollen shedding period and stigma viability ratio were synchronous. Pollen shedding phenomenon simultaneously occurred with the secretary activities of stigmas in all examined cultivars. Distribution of pollen shedding over the secretary activity of stigmas is almost good. In all five cultivars maximum pollen shedding occurred when the temperature was high during the day. In general the results of this experiment and our previous studies clearly demonstrate that the Pándy groups not recommended for plantation in new orchards of Iran.
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Estimating of water consumption of cherry trees
15-17.Views:210Despite of its importance there is no exact information on water use of new scion/rootstock composite trees, which would be needed to optimized irrigation. Our research purpose is to define exact water-demand of different rootstock/scion composite trees, calculating seasonal weather changes and by using the results decrease irrigation costs. The investigations are carried out in Soroksár, at the Experimental Farm of Corvinus University of Budapest in May 2008. From among the investigated trees two are budded onto Prunus mahuleb `Érdi V' seedlings, two on "Korponay' seedlings. The sapflow measurements are carried out using Dynamax Flow 32 equipment with Dynagage trunk sensors. The first daily maximum of sapflow was around 10:00 a.m. (2.5 kghour I), the second maximum was always between 14:00-15:00 p.m. (2 kgday- I). Comparing to the very intensive morning water uptake by 20:00 p.m. the water flow slowly reached the minimal level. Significant differences can be seen on rootstocks: trees on `Korponay' rootstock always showed more intensive sapflow and a higher morning peak than trees on `Árdi V'. But later during the day they have the same run.Based on our results the water quantity transpired only by the trees reached in May 86-104 mm, while the precipitation was only 42.4 mm. This means a 40-60 mm deficit in the orchard, which should have been supplied by irrigation despite of the satisfying horticultural performance of the orchard. In the first half of the month beside the steady vapor pressure deficit the shoot and leaf surface growth could cause the increased sapflow.
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Seasonality of weather and phenology of reproductive organs of flower of sour cherry cultivars in Hungarian climatic conditions
75-80.Views:249Sour cherry (Prunus cerasus L.) is one of the most important fruit crop grown in Hungary, The flowering phenology and pollen shedding/stigma viability ratio, in an effort to elucidate the reproductive phenology of nine economically important sour cherry cultivars (Érdi bőtermő, Debreceni bőtermő, Csengődi, Kántorjánosi 3. Pándy 279. Úfehértói fürtös, Petri, Éva, and Oblacsinszka) all widespread in the Hungary, was studied at Újfehertó climatic condition. The main aims were to investigate how possible environmental cues influence timing and development of phenophases and whether different cultivars have different seasonal responses to these cues. Likely effects of climatic changes on phenological development patterns were also considered. Our results revealed important aspects of the reproductive biology of sour cherry flowers. The amplitude of the phenophase "beginning of blossoming" between cultivars did not exceed 6 days. There is maximum 3 days difference in blooming length of different direction in each cultivar. Pándy 279 showed high variability when the position of flowers changed on the tree shoots. Újfehértói fürtös was stable in all four directions of tree. The pollen shedding period and stigma viability ratio was well synchronous. Pollen shedding phenomenon occurred in the range limitation of secretary activity of stigmas in all five cultivars. Distribution of pollen shedding over the secretary activity of stigmas is almost good. In all five cultivars maximum pollen shedding occurred about the high temperature part of the day.