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Agroclimatological properties of growing sites assigned to apple and pear production in Hungary
95-97.Views:849Apple and pear growing sites in Hungary are classified into four regions according to the Hydro-thermic Coefficient: dry, moderately dry. moderately humid and humid. Most of the plantations of apple and pear are located in regions considered as moderately dry and moderately humid. Within that category, the two respective species have different preferences, i.e. the ecological features of Hungary give different opportunities for apple and pear growing. Apple is grown almost everywhere in the country, successfully. The selection of cultivar-regions is needed mainly for increasing competitiveness on the market. Main apple growing regions are listed in 3 large groups. For the definition of cultivar-regions, mainly the configurations of soil and precipitation, i.e. conditions of the soil and opportunities of gaining water were decisive. Market factors are also considered. The area assigned to pear is much less than that of apple, in Hungary. Some well known and popular varieties would require high air humidity which cannot be presented in most of Hungary. Therefore, the possibility to establish regions for pear varieties is restricted, we have to create a particular micro-environment. Two groups are potential. The first one comprises sites where the annual precipitation is 700 mm, at least. There, apple and pear production would compete each other. In more dry habitats (less than 700 mm annual precipitation), micro-environments should be found and only drought-resistant, mainly summer-ripe cultivars should be chosen with, preferably, low tendency of sclereid formation. In that case, neither irrigation could help to produce adequate quality in varieties sensitive to low air humidity.
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Malus taxa and the progenies of Malus floribunda selected in Hungary, as gene sources of resistance breeding
25-28.Views:255One of our objectives in the apple breeding program of the Department of Fruit Science, beside creating new varieties, is to search for new gene sources. After evaluating the disease resistance of Malus taxa available in Hungary, we put the promising selected individuals through further examinations. Their habit and growth vigor was observed, as well as productivity and fruit characteristics were evaluated. Malus fusca seems to be a new, promising gene source in Hungary among the examined taxa. Beside its optimal canopy, growth vigor and fruit characteristics, it has the advantage to be in distant relationship to Malus x domestica, therefore its resistance is based on a different genetic basis. SBG 1 selection of Malus spectabilis can be recommended as a new gene source for resistance breeding. The range of gene sources can further be widened by selected clones of Malus floriblunda (BA I), Malus x zumi (BA) and Malus baccata (SBG 6). An additional value of Malus taxa chosen by us is that they show resistance not only to apple scab, but to powdery mildew as well, and according to our results, they have optimal habit, acceptable productivity and good fruit quality. Nine hybrids were selected from first Malus progenies which proved to be resistant to apple scab and powdery mildew. These are valuable not only as gene sources of breeding, but as pollenizers or ornamental trees, while their decorative fruits can be used in inside decorations and flower arrangements.
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The estimation of pollen viability of snowdrop (Galanthus nivalis L.)
141-144.Views:239In the present experiment pollen viability of snowdrop were tested using four vital dyes (TTC, Baker' procedure, MTT and FDA) to determine their potential to differentiate fresh living pollen from pollen heated for 12 hours at 80 °C (killed pollen). We found that two of the four dyes previously employed to determine viability also stained killed pollen in the case of snowdrop, while the FDA and MIT did not. We suggest that the two latter are probably the best method to test snowdrop pollen viability, since they do not normally stain either killed or aborted pollen.
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Increasing the vitamin D level of oyster mushrooms by UV light
119-123.Views:660Vitamin D is essential for the human body and mushrooms are one of the natural sources of it. Many research works are aimed at enhancing the vitamin D2 content of mushrooms with UV irradiation in order to increase their vitamin D2 level, by transforming their natural ergosterol content into vitamin D2. The subjects of most of these studies are different kind of post-harvest cultivated mushrooms. In our experiment biologically active, pre-harvest oyster mushrooms were treated in the growing room with UVB and UVC light. UVB and UVC lamps (operating on 312 and 254 nm) and 6 time periods of irradiation (15, 30, 45, 60, 75 and 90 min) were used. After three consecutive days of treatments the yield were measured and samples were taken for vitamin D2 and ergosterol analysis. Data showed considerable increase (from 0,67 μg/g to 3,68 μg/g, f.w.) in vitamin D2 levels at every time period in case of both wavelengths.
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Scab resistance in Malus sp. progenies - inheritance and resistance stability
9-15.Views:261Susceptibility of progenies of some Ma/us species to apple scab was evaluated. Susceptibility of hybrid families was observed first in greenhouse after artificial inoculations by the suspension of the pathogen, Venturia inaequalis (Cooke) Wint., then in open field. The Hungarian type of Malus floribunda, which proved to be scab resistant in our examinations, has a positive effect on the segregation of progenies to resistant and susceptible individuals as a male parent, not depending on the rate of susceptibility of the other parent. However, the German type of Malus floribunda and Malus prunifolia act as dominant, highly susceptible parents.
Malus x purpurea and Malus baccata, which proved to be highly susceptible to apple scab in open field and in artificial inoculations, transmits its susceptibility only slightly to its progenies as a male parent.
According to our experiments, the inheritance of scab resistance of Malus floribunda cannot be considered as monogenic, as published by other authors.
Scab susceptibility of parents influences the segregation of progenies to resistant or susceptible individuals. The moderately scab susceptible `Idared' as female parent has a statistically proved positive effect on the segregation of its progenies.
More factors indicate the appearance of a new race of Venturia inaequalis (Cke.) Wint.: change of the symptoms in the greenhouse; considerable increase of susceptible individuals after greenhouse inoculation in 1997; more and more progenies of the male parent Malus floribunda became susceptible to scab in open field.
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Effect of certain bentonite products on the temporal variation of elemental content in white wine
15-21.Views:192The 'terroir' character of wines can be shaped with certain technological elements such as bentonite fining. Bentonite is an agent used for the removal of thermolabile proteins in wines. However, during fining, the quantity of certain wine components can change, including the elemental composition of the wine. According to the recommendations of bentonite suppliers, wines should be racked off the bentonite fining sediment within 2-3 weeks. However, in winemaking practice, wines can remain on bentonite fining sediment for up to 1-4 months. One reason for this is that racking wines off the sediment has a negative impact on wine quality. Thus, it is a question of how much the later or earlier racking time can alter the elemental content of the wine. Our study aimed to examine the elemental content of wines treated with three different bentonite products sampled from over the bentonite fining sediment at various time points. Our investigation was conducted with the 2019 vintage white wine of the University of Debrecen. Fining was performed with three bentonite products: Nucleobent, BW200, and Granubent Poretec. The sampling schedule following fining was: 0 days - unfined control, 7th, 14th, 27th, 56th, and 85th days. The macro-, meso-, and microelement contents (P, K, Ca, Mg, S, Al, Na, B, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Cd, Ba, and Pb) of the wines were determined using ICP OES and ICP MS devices. Our results showed significant changes in the Al, Na, Cr, Fe, Co, Ni, Sr, Ba, Cu, and Pb contents of the wines depending on the sampling time. It is noteworthy that all three bentonite products increased the Al and Pb contents of the wines. For Fe, dynamic increases were observed over time with the BW200 product, reaching the threshold value of susceptibility to brakeage. However, from a winemaking technology perspective, it was favorable for the Cu content of the wines to decrease with both earlier and later racking times, for all bentonite products examined. Based on the elemental analyzes of the white wines studied, it can be concluded that racking of wines should be timed according to the recommendations of suppliers.
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The necessity and possibilities of irrigation in fruit growing under conditions of Hungary
93-94.Views:779Climatic and soil conditions are highly suitable for most temperate fruit species and promise profitable yields with good quality. An accurate choice of the growing site is, however, decisive because of the wide range agro-climatic variation an soils within the country. One of the most important factors is the annual precipitation which does not exceed, in general, 700 mm. The aims of irrigation practices are, succinctly speaking, the improvement of quantity and security of yields and the guarantee of quality. The relative importance of those criteria changes according to the fruit species. In up to date apple, pear and cherry production, micro-irrigation systems are mainly considered. According to recent experiences, the micro-jet type of water distribution should be preferred to the dripping system. In cherries, the choice of the method is motivated by the need to prevent fruit cracking. Most of the peach and apricot plantations are located on the dry and moderately dry regions of the country. Because of the late freezes, the improvement of security is crucial. There the investment of irrigation systems should concentrate to the possibility of anti-freeze sprays. High water requirements of plums are met in Hungary by irrigation where the method should be decided at the plantation and adapted to the harvesting procedure which could be mechanised or (in high density plantations) picked by hand. Sour cherries are perhaps the less dependent on watering under Hungarian conditions. Yields in small fruits: currents, gooseberries, raspberries and strawberries could be increased by irrigation to 40-50 % and may improve quality too. In those cultures the system of moving flexible wing tubes are considered to be the best irrigation technique.
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Evaluation of fruit quality parameters of Rosa taxa from the Carpathian basin
81-87.Views:282From the wide range of genetic sources available in Hungary, we have chosen as objective the evaluation of those rose taxa, which — on the base of their quality and morphologic features — are suitable for selecting fruit production varieties or parent varieties for further breeding. We examined physical and inner parameters of fruits of Rosa taxa, and evaluated the correlations by mathematical statistic methods. Namely, if a correlation can be found between physical and inner parameters, fruit production value can be determined by less examinations in the future. According to our results, there is a large variability in some physical parameters (weight, diameter of fruits; weight, number of achenes) as well as in inner content values (vitamin C, glucose, fructose, K, Ca, Fe, Zn and Cu content) of rosehip, regarding production year, habitat and even the individual of examination. Twice as much ascorbic acid can be found in achene-free fruits, and nearly five times as much in their dry product as in fresh whole fruits. It was established repeatedly, that vitamin C concentrates in fruit flesh, and ascorbic acid content can be preserved better in achene-free flesh. There is no essential difference in citric acid and carbo-hydrate content of whole and achene-free rosehips. However, macro- and microelement content of whole fruits is 30-40% higher than that of achene-free fruit flesh. The connection between fresh weight and diameter, as well as achene number and seed weight of fruits can be described by the function y=axb. A significant relationship can be found in case of K-Fe, Ca-Mg, Ca-B, Ca-Mn and Zn-Cu, between fresh weight and B content of fruits. According to our examinations, fresh weight of rose species with a higher citric acid content is usually higher, while their Fe content is smaller. Glucose content of fruits of rose species is directly proportional to their Ca and Zn contents. Zn content of rose species with higher fructose content is usually smaller.
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Pollen viability of ‘Besztercei plum' clones depending on the effect of the year
115-121.Views:546The percentage of dark staining pollen grains was higher in spring of 1996 than in the previous year. Data in 1998 resemble those of 1995, concerning the large amount of medium staining pollen grains in the majority of clones. Some clones produced excellent quality pollen also in the third year. whereas there were significant differences in other clones in various years.
The warmer February-March period in 1995 induced an early blooming, and frost affected the orchard not only in winter months, but also immediately before and during blooming. Thus, frost was the possible cause of weaker quality pollen this year. In 1996 warming began a bit late, but it was not broken by drastic falls in temperature, except for the middle of April, when a smaller frost affected the orchard. It is likely that this frost did not influence pollen quality of `Besztercei' and 'Early Besztercei' plum clones significantly. In 1998 warming was continuous and steady, the orchard was not affected by frost immediately before blooming. In March, however, there was frost almost every day, according to daily minimum temperatures.
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Ripening related processes in strawberry, a nonclimacteric fruit: a short overview
105-109.Views:413Fruits are essential part of the human diet: they provide vitamins, minerals, antioxidants to the mankind. Physiologically they can be divided into two groups-climacteric and nonclimacteric - depending if they display any respiratory peak and dramatic increase in ethylene biosynthesis or do not. Ethylene is a gaseous hormone playing a very important role in several physiological processes in plants. While climacteric fruits, like apples, bananas, tomatoes, peaches, apricots show increased ethylene biosynthesis and dramatic respiratory peak during their ripening, nonclimacteric fruits, like strawberries, grapes, citrus do not.
The most widely used fruits for studying nonclimacteric ripening are strawberries: several papers are focusing on the identification and characterization of ripening related genes from this plant. Therefore here we attempt to summarize the most important advances in strawberry fruit development, and ripening.
