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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. -
Water relations of sour cherries (minireview)
103-107.Views:229Recently, the sour cherries as food resources become more important for health preservation and so the modernization of growing technology in sour cherry production will be timely. The global warming and inadequate distribution of precipitation result a decrease in the alternancy of sour cherry production, as well. Sour cherries rather adapted to survival of drought than sweet cherry trees therefore a few studies performed to explore the water requirement of sour cherry varieties. The rootstocks, the type of soils in plantation and the water balance influence the water management of sour cherries. In orchards, in particular first year plantation, use of various row covering contribute to preservation of the natural water pool of soil and affect on the tree vigor, yield and fruit quality. Wide-spread application of integrated fruit growing technology and climate changes the researches are pointed to develop efficient irrigation technology based on transpiration yield model. The crop model based on use of meteorological data was developed for cherry orchards in order to predict transpiration of trees, dry matter production and fruit yield. The linear relationship between dry matter accumulation and transpiration was verified for sour cherry trees. Other models essay to asses the effects of climate changes on crop production. Importance of economical production and fruit quality such as ingredients of raw materials and food increases in intensive sour cherry orchards used by irrigation techniques. Because of climate changes it should more pay attention to research concerning on the stress physiological response of sour cherry varieties and post-harvest fruit quality.
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Integration of terrestrial laser scanning and spectral canopy scanner in horticulture applications
15-18.Views:286One of the most difficult challenge in the everyday practice to describe the canopy growing of fruit trees in an orchard. The photosynthetic activity is the basic of the primer production of plants. The measurement of leaf area and determination of the photosynthetic activity could be occurred with some elaborated methods between experimental conditions. In this article we present such an integrated methodology, which is ideal to determine the geometric and spectral characteristic of fruit trees between field conditions.We have carried out laser scanning technology to investigate the geometric-topological characteristics and parallel the active infra-red sensor to collect spectral data about an apple orchard. The surveys were worked out in an intensive apple orchard with drip irrigation system, protected by hail net in Study and Regional Research Farm of the University of Debrecen near Pallag. This study shows the filtering and interpretation methods of created data. The produced high accuracy data can be directly used in the precision horticulture. It could serve as a guiding data to implementation a future “virtual horticulture”. Higher spatial and temporal resolution could help for a better recognition of water balance of orchards.
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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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Chemical communication with volatile semiochemicals in Phyllotreta species (Coleoptera, Chrysomelidae): a minireview
93-100.Views:204Phyllotreta species (Coleoptera, Chrysomelidae, Halticinae) rank among the most important horticultural pests in the Northern Hemisphere. Leaf damage caused by flea beetles upsets the water balance, blocks plant growth and sometimes causes a high level of mortality of seedlings. Several species are known to act as vectors of numerous pathogens as well. Chemical communication plays an important role in the host finding, feeding and oviposition behaviour of flea beetles. In the first phase volatile mustard oils (isothiocyanates and thiocyanates) are released from the host plants through the decomposition of non-volatile glucosinolates (chemicals specific to Cruciferae) by myrosinase, and beetles are attracted to the source of release from a distance. Among the isothiocyanates, allyl isothiocyanate is the longest known and widespread compound utilized in the host-plant location of Phyllotreta species, but some species may have a stronger preference to other isothiocyanates or thiocyanates. The attractive effect of the plant volatiles is enhanced by the emission of a male-produced aggregation pheromone. The presence of such a pheromone was first demonstrated in Phyllotreta cruciferae Goeze. In this species R5R,5aS)-1,1,5,8-tetramethy1-1,2,3,4,5,6,5a-heptahydrobenzo[1,2-a][7]annulene] was found to be the main pheromone component. Significant attraction by the pheromone was recorded only in the presence of ALLYL ITCN. The biological activity of the pheromone compound was connected to the plus (+) chirality. The same component seems to be occurring also in the pheromones of several other Phyllotreta spp. as well, suggesting a wider occurence in the genus. Once attracted by the joint effect of plant volatiles and aggregation pheromone, the presence of the non-volatile glucosinolates in the plant tissues is necessary for continuous feeding. Aggregations of flea beetles on suitable host plants, which result from the joint effects of plant-derived and pheromonal chemical cues detailed above may also be good rendez-vous occasions, increasing the probability of encounters with the opposite sex and mating in the vicinity of the optimal oviposition site. Due to the horticultural importance of Phyllotreta spp., deciphering details of their chemical communication has considerable significance in the development of new methods of integrated control.
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The utilisation of nutrient elements in soilless cultures of vegetable production
47-49.Views:203Vegetable production in greenhouses may impair the ecological balance of the environment substantially as far as being uncontrolled. Soilless cultures especially should be handled thoughtfully. A fraction of the nutrients administered, more than 25-30%, is doomed to be lost in an open system, and the resulting ecological risk is accompanied with increasing costs of the production. Experiments have been conducted with the purpose of estimate the amount of nutrients involved. According to the results, as a mean, 30-80 per cent of the main nutrients was utilised. The rate of nutrient utilisation is influenced by the plant species involved as well as by the circumstances of production. One of its most important components is the irrigation, which determines the amount of overflow and of its salt content.