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The brown rot fungi of fruit crops (Monilinia spp.): II. Important features of their epidemiology (Review paper)
17-33.Views:677Plant disease epidemiology provides the key to both a better understanding of the nature of a disease and the most effective approach to disease control. Brown rot fungi (Monilinia spp.) cause mainly fruit rot, blossom blight and stem canker which results in considerable yield losses both in the field and in the storage place. In order to provide a better disease control strategy, all aspects of brown rot fungi epidemiology are discribed and discussed in the second part of this review. The general disease cycle of Monilinia fructigena„M. laxa, M. fructicola and Monilia polystroma is described. After such environmental and biological factors are presented which influence the development of hyphae, mycelium, conidia, stroma and apothecial formation. Factors affecting the ability of brown rot fungi to survive are also demonstrated. Then spatio-temporal dynamics of brown rot fungi are discussed. In the last two parts, the epidemiology of brown rot fungi was related to disease warning models and some aspects of disease management.
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Effects of excessive weather on the micro-climate of apple plantations under the hail protection nets
81-85.Views:32345The general utilisation of hail nets is spreading all over the world and in Hungary too. Hail nets are at present the only tool, which
is able to prevent heavy hail damage in agricultural crops. Besides its numerous advantages, there are also deleterious side effects, e.g. it
changes the microclimate of the crop stand. Our study aimed to observe the differences, which characterise the physical status of crop stands
under the protection of hail nets compared with the stands in open air under various meteorological conditions: high or low temperature, calm
or windy atmosphere and their possible combinations. The results indicated that on hot and calm days the difference may attain 3–4° C. On
cool summer days, the difference was only 1.5 ºC. The hail net influences the relative humidity of the air, which means on ho summer days
often 7-8% differences. Conditions of radiation may also differ conspicuously. Measurements prove the reduced global radiation on sunny
summer days to 70%. This impairs as a rule the development of fruits reducing their quality and also its quantitative traits. Sunburn is, on the
other hand, significantly prevented by shadow. -
Studies on the Tobamovirus resistance of the pepper (Capsicum annuum L.) cultivar Greygo
71-75.Views:267Resistance of the Hungarian pepper (Capsicum annuum L.) cultivar "Gre.ygo" to Tohamoviruses has been investigated. All plants of the population of Greygo proved to be resistant to tobacco mosaic and tomato mosaic viruses (TMV, ToMV), both represent the pepper pathotypes Po of Tohamoviruses. Individuals of Greygo, however, were found to be susceptible to pathotypes P12 and P123 of pepper mild mottle virus (PMMV). When inoculated with the XM isolate of dulcamara yellow fleck virus (DYFV, pathotype P1) the population of Greygo segregated in resistant and susceptible plants. These results as well as inoculations of the progenies of three TMV resistant plants clearly showed, that besides the resistance allele Li the cultivar Greygo possesses also an another allele. This allele, provisionally marked by L2g behaves like to the allele L2 characteristic to Capsicum frutescens cv. . Tabasco. Determination of the identity of the allele L2g to the allele L2 needs further genetic and pathological informations. Relations between the Tohamoviruses pathogenic to pepper and the alleles of the resistance gene L are outlined for the discussion.
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Histological studies on small bulb flower crops
83-85.Views:278Investigations were done in order to obtain more information on the histological structure of bulbs of Allium moly, Allium sphaerocephalon, Muscari armeniacum and corms of Crocus sativus. While starch grain were found in the bulb of Muscari armeniacum, fluid nutrient content were shown in Allium species. Narrow and fleshy scales were found in the bulbs of Muscari. Histological characteristics of Allium moly and Allium sphaerocephalon showed a closer relationship with corms than with the bulbs. To clarify this question, further investigations are needed (Bailey, 1942; Larson, 1980).
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Changes in the Dry Matter and Sugar Content of Nantes Type Carrots during Storage
67-71.Views:332Changes in the dry matter and sugar content occurring during the winter storage of Nantes type carrot hybrids grown on soils of different quality were studied in 199912000 and 200012001. The dry matter content of the varieties tested depended on the production site and on the weather conditions prevailing in the growing season. The increase in the dry matter content during winter storage reached 6 to 7 per cent in the crop grown in a dry year and 1.5 to 2 per cent in a rainy year. The sugar content was lower in the rainy year (1999) and on brown sand (Szatymaz) than in the rather dry year (2000) and on chernozem soil with residual forest (Tordas), respectively. The increase in sugar content (1 to 5 per cent) measured at the end of storage was related to the season's weather conditions.
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Influence of abiotic factors on the green mass and seed productivity of the raw material of Levisticum оfficinalе c. Koch in the conditions of Transcarpathia
46-51.Views:540For the wide implementation of Levisticum officinalе C. Koch in Transcarpathia into production it is necessary to widen its sort composition, as it is rather poor in Ukraine. Solving this problem is possible by enriching the source material with the samples of different ecological and/or geographical origin, by studying the influence of abiotic factors on the formation of green mass and seed productivity, separating the specimens best adapted to the conditions of growing, involving them into the selection process and creating new, highly productive sorts on this basis. The scientists of the Transcarpathian State Agricultural Experimental Station (TSAES) conducted researches (during 2011-2016) on the adaptive potential of the source material of the type of Levisticum officinalе C. Koch, which counts seven samples (Ukraine – 5 samples, Poland – 1, and Romania – 1), the selection work on creating new varieties for the given region is being done. The investigations were made on soddy podzolic gleyed low-humus soils with low content of nutrients. The results were obtained on the basis of generally accepted methods of investigation, i.e.: laboratory, field, visual, measuring-weighing, biochemical, mathematically statistic, and comparative-calculating. In the conditions of Transcarpathia the spicy greens of the high quality L. officinalе C. Koch are being gathered on days 25-30, the output of the essential oil makes up from 0.72 tо 1.89% on c.d.s., depending on the climate conditions of growing. The plants pass through all the stages of development, the bush is 55.4 to 92.7 сm in height, the plants form a big amount of rosette-shaped stems (11-34 pieces), the productivity of spicy greens is between 9.9 and 42.1 t hа1. The scientists of TSAES created the following sorts – Mriya (А. с. 06131 Ukraine, first registered in the State register of plant varieties of Ukraine) and Coral (Pat. on the variety № 140830). Economic effect from growing of the Coral variety in the conditions of Transcarpathia is 10230 UAH/ha and the level of profitability is 28.4%. The geographic position and agroclimatic conditions of Transcarpathia, as well as the unpretentiousness of L. officinalе C. Koch. tо the conditions of growing contribute to the enrichment of the local flora with useful plants; and the rich chemical composition contributes to the spread of this culture in the given region.
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Carotenoid composition and content in products of sea buckthorn and peach as determined by high-performance liquid chromatography
69-74.Views:1357A study was conducted to analyse the carotenoids by high-performance liquid chromatography (HPLC) using reversed-phase cross linked end-capping and to study the pigment content and composition in sea buckthorn products as well as in freshly harvested fruits from peach thees grown under organic and integrated farming conditions. It was found that carotenoids in fruits of both crops occur mainly esterified with fatty acids in form of mono- and di-esters. The major carotenoids were esters of zeaxanthin, lutein, β-cryptoxanthin and β-carotene. The major carotenoids showed different response to processing of sea buckthorn being highly sensitive to thermal treatments such as blanching, cooking and drying. Significant differences were found between peach varieties in their carotenoid content, whereas the impact of organic farming on carotenoids formation was found to be variety-dependent. Two of the three varieties examined in this work, when cultivated under organic farming conditions contained lower carotenoid level as compared to that found in the fruits of the same varieties but produced in integrated farms.
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Studies for using frameless plastic in the forcing of some ornamental crops
148-150.Views:290On the basis of a six-year experiment a method was elaborated for forcing and off-seasons growing of tulips, narcissus and gladioli under frameless plastic cover. The advantages of this cheap energy-saving method are manifested in an improved quality of flowers and essentially in the earlier flowering. With this method mostly first-class flowers can be obtained immediately after the season of forcing in heated constructions with plastic cover, and anticipated outdoor flowering.
The possibilities of applying the method are studied on further ornamental plant species (other bulbous plants, Paeonia lactiflora, annual ornamentals).
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Effect of seedling quality on growth, yield and quality of tomato (Solanum lycopersicum L.)
64-72.Views:742A two trial greenhouse experiment was carried out at Rwanda-Israel Horticulture Centre of Excellence located at Mulindi Station to evaluate seedling quality on growth, yield and quality of tomato. The seedlings were grown in different growing media and produced seedlings with varying quality indices. The growing media of peat moss 100% (T2) and sand + goat manure + carbonized rice husks 50%: 10%: 40% (T8) were revealed in seedlings with the highest mean quality indices of 31 and 28 respectively, while sand 100% (T2) presented the lowest quality indices during both trials. The transplants were planted in polybags filled with 2:1 of topsoil and kitchen manure arranged in a randomized complete block design (RCBD) with four replications. Collected data were subjected to analysis of variance and means were separated using HSD test at a 5% level of significance. The results revealed that the seedlings grown in T1 (S1) and T8 (S8) consistently presented tomatoes with better growth performance and yield. S1 and S8 produced mean yield of 93.59 and 92.35 t/ha respectively while S2 had the lowest yield with 53.86 t/ha. The fruit produced from seedlings grown in T4 (S4) had the highest mean sugar acid ratio of 5.88 but not significantly different from 5.61 and 5.44 of S1 and S8 respectively. Hence, there was a positive relationship among seedling quality and growth and yield performance of tomato but not in fruit quality.
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Allyl isothiocyanate baited traps to monitor cabbage flea beetles (Phyllotretra spp., Coleoptera: Chrysomelidae)
95-99.Views:473A new trapping concept has been proposed based on a volatile compound, allyl isothyocianate, known to be attractant to some of these insects for a long time.
(l) The first question was whether this compound is effectively attractive to all flea beetle species attacking cabbage under our conditions? Field experiments were made at different localities with non-sticky baited traps early and late spring. Eleven Phyllotreta species attacking cabbages were captured at baited traps most of them were first observed at this bait. So the bait has proved to be sufficient for use for trapping purposes effectively.
- Based on these findings a second question arose whether the captured samples reflected the specific composition of natural flea beetle populations at trapping localities? To reply the question field samples were taken at four different kinds of cabbage crops and at a fallow ground in the close vicinity by a manual sampler device suitable to detect the local composition of flea beetles and trapping was made parallel with baited and unbaited traps from early spring to early autumn. No significant differences were found between the specific structures of Phyllotreta assemblages sampled with the different methods applied. This means baited traps reflected the specific composition of local Phyllotreta populations fairly well.
- Thirdly, the most effective trap design was searched for. Some sticky and non-sticky trap designs which had been developed to capture other insects were compared. The tested sticky and funnel trap designs baited with allyl isothiocyanate captured large numbers of flea beetles attacking cabbages. Results showed that non-sticky funnel traps were more effective than sticky delta traps. Accordingly, non-sticky funnel trap designs can advantageously be used and could possibly be recommended in plant protection practice to monitor flea beetles attacking cabbages as their catching capacity is considerably greater than that of the delta type and additionally captured beetles are much cleaner, more intact and consequently their identification is much easier.
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Salt tolerance of sweet pepper seedlings
62-66.Views:408Laboratory germination tests have been made with three white fruit pepper varieties and with one spice pepper in filter paper rolls wetted with KCl solutions of different concentration. Parallel tests have been conducted with the other species (lettuce, tomato, kohlrabi) to compare the salt tolerance of paprika with that of other vegetable crops.
In greenhouse, the action of KCl has been investigated with transplants raised in soil mixture, in rockwool and with seedlings transplanted from rockwool into soil mixture. Like the trials in the laboratory, the experiments in soil mixture have been made with other plant species, too.
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Giant reed (Arundo donax L.) from ornamental plant to dedicated bioenergy species: review of economic prospects of biomass production and utilization
39-46.Views:909Giant reed (Arundo donax L.) is a perennial, herbaceous grass, it has been spread all over the world from continent to tropical conditions by human activities. In continental climate, especially Hungary, it has been considered as ornamental species, due to its decorative appearance, striped variants’ colour of leaves, long growing season and low maintenance requirements. It does not produced viable seeds, so it can be propagated vegetative ways by rhizomes or stem cuttings and by in vitro biotechnology methods. Because of its growth habits and good adaptation capability, it has been considered invasive weed primarily in coastal regions in warmer climate areas. In the previous century, giant reed produced for paper/cellulose/viscose production, woodwind musical instruments, stakes for plants or fishing rods etc. Over the last few decades, it has been produced for bioenergy purposes (bioethanol, biogas, direct combustion) or utilize as chemical basic compounds or construction materials. It has been considered a dedicated promising biomass crops thanks to high biomass production, high energy balance of cultivation and adaptability of different kind of soils and conditions. The objective of the present paper is to overview the most significance literature data on giant reed production and utilization, compare to own experimental data and economic calculations and to determine some critical factors, advantages and disadvantages of giant reed production compare to other biomass species.
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Effect of water supply on canopy temperature, stomatal conductance and yield quantity of processing tomato (Lycopersicon esculentum Mill.)
13-15.Views:556Tomato (Lycopersicon esculentum Mill.) is one of the most extensively cultivated horticultural crops in the world.Water supply is important for yield quantity and quality. The aims of the present study were 1) to evaluate the canopy temperature and the stomatal conductance on processing tomato substances with different water supply, 2) to investigate the effect of different water supply on yield quantity. There were two irrigated treatments, one of them was the reguralry irrigated plant stand which got 333 mm water during investigated period, including the precipitation and the other was the cut off substance which means the irrigation (drip) was stopped at the beginning of the ripening process and there was a control as well which got 189 mm precipitation. The canopy temperature was measured row by row with a Raytek MX 4 type infrared remote thermometer. The stomatal conductance was measured by Delta-T AP4 type porometer. There were significant differences between the control and irrigated plants according to the water supply which was formulated the canopy values. The plants with a deficient water supply were decreased the transpiration rate, therefore its cooling effect didn’t show up. The regularly irrigated tomato plants’ yield exceeded the unirrigated ones more than twice. It is emerged from the study that the irrigation has a positive effect on the amount of the harvestable yield in this year type.
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Effects of silicon in plants with particular reference to horticultural crops - Review article
95-105.Views:644Silicon (Si) has long been considered as non-essential element for plant’s growth and production. Numerous efforts are being made for the discovery of its beneficial effects with large scale studies laying foundation for new findings and hypotheses. Therefore, Si has been suggested to be a quasi-essential element due to its positive effects against biotic and abiotic stresses alike. Though Si is the second most abundant element in the soil profile, its availability to plants is limited to the form of monosilicic acid only. Besides, plants’ ability to take-up Si and use it in their physiological processes also depends on the available transporters associated with it. Thus, the present review covers uptake and transport of silicon in plants as well as Si mediated physiological processes, including mechanisms underlying induced tolerance against biotic and abiotic stresses with a particular emphasis on horticultural species.
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Scheduling of irrigation in snap bean (Phaseolus vulgaris var. nanus) using canopy temperature
89-94.Views:279The present paper evaluates the result of irrigation experiments carried out on snap beans sown in spring and summer and grown with and without irrigation. The experiments were run over the course of 12 years. In the average of 12 years, the yield was 2.8t ha-I for spring sown and 1.9 t ha-I in summer-sown plants without irrigation. The lowest level of profitable production, the 5.5t ha-I was reached twice in the case of spring sowing and only once in the case of summer sowing. Profitable yield production can be ensured only with regular irrigation and thus the yield may be increased by 4-5 times. In four of the twelve years we determined the canopy surface temperature of snap bean stands with and without irrigation. A Raynger II infrared remote thermometer determined the canopy surface temperature every day at 13.00 hours. The canopy temperature can well characterize the water supply of plant stands. This parameter may be used for describing the degree of drought and the water turnover of plant stands with different water supply. The positive values of foliage-air temperature differences (SDD) numerically express the degree of drought and the water supply of the crops. The results indicated that a 1 °C higher SDD value may cause 90-130 kg/ha yield loss.
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Review of the self-incompatibility in apple (Malus x domestica Borkh., syn.: Malus pumila Mill.)
31-36.Views:947Apple (Malus x domestica Borkh.) is one of the most important fruit crops showing ribonuclease-mediated self-incompatibility, and no self-compatible apple cultivars are known. Twenty-nine S-alleles were identified in apple and many more incompatibility groups are present compared to sweet cherry. Results from a Belgian, English and a Japanese research group are combined and the S-genotypes of the most important world cultivars are collected. Two different allele labelling system are reconciled and detection methods used in case of the specific alleles are shown. Effects of the resistance breeding programmes are discussed; and scientific efforts involving transgenic technology to create self-compatible genotypes are shown. This review covers the most interesting issues regarding self-incompatibility in apple.
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Fruit drying traditions in Hungary
7-10.Views:683Since the early eras of human history, the gathered products (roots, shoots, crops, fruits etc.), the environmental conditions of the preservation of the animals caught and the fishes; and accidental observations have been born new methods. Under cold and moderate climates, the effect of permanent frost, the use of ice as a means of curing as in dry, desert areas is the drying or exsiccation and the dehydration of salt. For convenience reasons, some of these methods have been forgotten, but the resurfacing of different fruits seems to resume. The short review gives an overview of the methods of drying used in the Carpathian Basin, especially among the Hungarian ethnic groups, which by the Hungarian ethnology thoroughly explored. The author attaches outstanding importance to the fruit-drying industry, because dried-ups at industrial scale are not equivalent to traditional low-fat lime scales. Excellent drying products are much better in terms of eating habits, with modern methods and small-scale production relatively easy to produce.
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Irrigation modeling in a pear orchard
75-79.Views:1015The pear has large water requirement, therefore the planting of high density and grass covered pear orchards are needed irrigation
conditions in Hungary. Drip irrigation spread in the orchards is due to the 90–95% of water use efficiency. One of the key role of irrigation is the
proper determination of evapotranspiration and crop coefficients. As there is a considerable lack of information for different crops or fruits the
Penman-Monteith method is used for the estimation of evapotranspiration, using CROPWAT 8.0. The research field was the genetic collection of
pear at Újfehértó, in Hungary, which is situated in Nyírség meso-region. Our aim was to establish drip irrigation at this site. Based on the results
of CROPWAT irrigation model the mean amount of the total gross irrigation is between 230–270 mm, within 3 irrigation interval regarding
climatic and rainfall data of the last 10 years. In 2009, due to heavy drought, the total gross irrigation was 355,4mm/year on sandy soil calculating
with 45% total available water depletion in 5 irrigation interval. The sizing of the irrigation system was set to the maximum 0.55 l/s/ha, which is
6.3 l/tree/h. 6.3 l/tree/h can be carried out with a drip emitter having 16 mm wing lines diameter, 4 l/h water flow at 3 atm pressure. -
Preliminary data on attractiveness of phenylacetaldehyde-based lures on economically important plant bug pests (Hemiptera: Miridae)
87-94Views:831Several plant bug species (Miridae) are important pests of crops and vegetables, thus monitoring them is of essential importance for effective pest control. During the current, preliminary study synthetic plant volatile combinations were tested in field conditions in Hungary in alfalfa fields. Beside semiochemical baited traps, sweep-netting was also performed. In the experiments three plant bug species were found in higher numbers: Adelphocoris lineolatus, Lygus rugulipennis and L. pratensis. As a novel, interesting finding L. pratensis was attracted to phenylacetaldehyde baited traps. For all species, both males and females were trapped in all combinations. Sweep-netting and semiochemical baited traps showed different efficacy in case of the three species, as sweep-netting catches were highly biased for A. lineolatus, which indicates the higher efficacy of this method as compared to the tested semiochemical-baited traps. On the other hand, semiochemical baited showed better performance for L. rugulipennis and L. pratensis. For these species none of the tested combinations performed better than phenylacetaldehyde baited traps. The potential implication of results in view of monitoring are discussed.
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Adaptation of temperate climate horticultural plants in tropical and subtropical developing countries II. General characteristics, Hungarian experiences and possibilities
5-11.Views:4575The cooperation of Hungarian professionals with Chinese, Thai, South-Korean, Taiwanese and Brazilian colleagues should deserve much more attention than actually done. We refer to the transfer and adaptation of production technologies as well as biotechnological developments in vegetables, fruits, ornamentals and medicinal plants from the Temperate Zone to the tropical and subtropical regions. According to our information Hungarian colleagues involved in extension work are highly esteemed on the same level as Japanese, Chilean, Italian and French colleagues. We could state that immigration of investors, local enterpreneurs as well as those coming from expansive regions of Europe, North America and oversses, representaives of supermakets keeps to be accelerated by the increasing confidence triggered also by the successful management of profitable plantations, vineyards and fruits initiated first about 15 years ago.
For Hungary, the presence and achievements of Hungarian horticultural expertise in tropical and subtropical zones yielded unequivocal advantages. Therefore, the next actual step of development would mean the organisation of a network of the "Units of Horticultural Mission" in the tropic and subtropic countries. We are convinced that those Units will stimulate the traffic of technologies as centers of transfer within and between the regions and contribute to the increasing influence of professionals on the production and trade of horticultural commodities. The introduction and testing of new varieties of vegetables, fruits, medicinal plants (as well as ornamentals), the development of the growing technologies, adaptation and acclimation of Temperate Zone germ plasm representing the general trends of advanced production will be the most important tasks of the Mission with a sufficient oversight upon the whole world. It is taken as a fact that Hungarian horticulture and breeding is competitive on the world market. We are ready to contribute to the development of horticulture on a worldwide scale. The Hungarian R & D will be attentive in the future to manage the accumulated capacities by information and mediating needs and offers to the volonteers of the profession. The reality of the above propositions are amply proved by successes of the Agroinvest Co and of other professionals registered in abroad.
To keep on the top of the world list of the profession we have to follow up the international trends by our permanent presence on the most important centers of administration and production of the world in order to hold on the hot line of the Hungarian administration competent in financing the R & D activities. We need specialists which are open minded, speak languages, familiar with the tricks of informatics, economics and politics, competent in deals, able to make decisions, etc. The education and training should be strenghtened to he conform with those trends. That proposal involves also the need to follow up the activities of the transnational companies, the regular, active participation on international conferences, the permanent attention paid to electronic informations available in the worldwide networks as well as the printed periodicals of horticulture. It is also related to the attraction of investors to the developments aimed within the country as well as abroad. At last but not at least we have to keep in mind that the work performed abroad by the Hungarian professional is a kind of "para-diplomatic mission" which cannot be substituted by any other, sometimes very expensive activity charged on the officia erliplomatic missions. The benefit of it is, however, valid to the whole country because false stereotypes developed during the last 50 years cannot be abolished otherwise.
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Review of the molecular background of self-incompatibility in rosaceous fruit trees
7-18.Views:480This review gives a presentation of the gametophytic self-incompatibility system in the roscaeous fruit trees. Studies to discover the pistil (S-ribonucleases) and pollen-part components (F-box molecules) are summarized and models for the self-incompatibility reactions as well as their molecular background are discussed. We describe how mutations within the S-RNase or F-box genes can contribute to the transition from self-incompatibility to the self-compatible phenotype in many fruit tree crops. The current state of the arts is compared to the information obtained in other plant species possessing similar incompatibility system.
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Fungicide resistant Trichoderma strains causing compost infection in shiitake production
67-70.Views:258Trichoderma infection represents the major problem of shiitake production in the growing house of the Research Institute at Kecskemet. Heavy infections occur mainly on the compost before spawn run. All the isolated strain belongs to the species Trichoderma harzianurn, but morphology of the colony indicates that there are more strains liable for the infection. Source of infection remained unclear but the Trichoderma strains can be considered as weed moulds rather than true pathogens of shiitake. All the Trichoderma isolates showed unusual high degree of resistance to fungicides.
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Brown rot blossom blight of pome and stone fruits: symptom, disease cycle, host resistance, and biological control
15-21.Views:1877In this paper, important features of symptoms, biology and biological disease management are summarised for brown rot blossom blight fungi of pome and stone fruit crops (Monilinia laxa, Monilinia fructicola and Monilinia mali). Firstly, European brown rot caused by Monilinia laxa is discussed highlighting the blossom epidemiology features, then host susceptibility of the most important stone fruit species including several Hungarian and international cultivars. At the end of this chapter, recent biological control possibilities against Monilinia laxa are also included. Secondly, American brown rot caused by Monilinia fructicola is discussed. Symptoms, biological features of blossom blight and host susceptibility of flowers to Monilinia fructicola are demonstrated. Finally, the symptoms and the biology of the least frequent species, Monilinia mali are shown.
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Reactions of some cucumber (Cucumis sativus L.) lines and hybrids to zucchini yellow mosaic virus (ZYMV) and selection of tolerant breeding lines
66-68.Views:343In the past years zucchini yellow mosaic virus (ZYMV) has been appeared as a new pathogen of cucurbitaceous plants in Hungary. It caused severe disease outbreaks on the fields of pickling cucumber hybrids which are highly tolerant to cucumber mosaic virus (CMV). Preliminary inoculation tests have showed that all of the important pickling cucumber hybrids produced in Hungary were susceptible to ZYMV-P. However, a selection of Chinese Long and the breeding line I- KS 10C proved to be highly tolerant. The Fl plants of the crosses between the tolerant lines and the susceptible genotype H I were susceptible to ZYMV-P. F2 populations segregated for susceptible and tolerant individuals at a ratio of 3:1. The results strongly suggest that the resistance to ZYMV in our sources is controlled by a single recessive gene. Inoculations of the ZYMV and CMV susceptible cultivar Budai csemege and the CMV tolerant hybrid Perez Fl with the complex of ZYMV+CMV resulted extremely severe symptoms (strong mosaic and necrotic spotting of the leaves) on both cultivars. On the Chinese Long line, which is tolerant to ZYMV and CMV, respectively, the complex of the two viruses caused mild symptoms. The results show a synergistic pathological effect of ZYMV and CMV on differrent cucumber genotypes. More detailed studies on the interactions among the plant genotypes, viruses and virus strains are needed to develop cucumber hybrids that are highly resistant to the ZYMV+CMV complex.
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Correlation between pigment contents and FRAP values in beet root (Beta vulgaris ssp. esculents var. rubra)
85-89.Views:540It is well known that beetroot quality is determined mainly by the red pigment content (betacyanins) and its uniformity of the root. The effect of the most important red pigment components (betanin). the total polyphenol content and antioxidants were studied in 20 beet root varieties. Antioxidants were expressed in FRAP (ferric reducing ability of plasma) values in pM/I.
Our results indicated a close correlation (r = 0.7799 and r = 0.7435. respectively) between betanin and total polyphenol contents of the root as well as between FRAP values.
Our measurements showed more than threefold differences in total antioxidant activity among varieties. the lowest value being 196.4 13M/1 and highest 702.57 pM/I. The corresponding betanin (16.3 and 57.8 mg/100 ml) and total polyphenol (37.5 and 85.5 mg/100 ml respectively) contents show similar differences. Based on our results it can be stated that varieties of higher betanin and poliphenol contents have higher antioxidant values as well.
Accordingly, the two compounds must have a role in the evolution of antioxidant effects.
