Mechanical behavior of catching surfaces used for fruit harvesting59-64.Views:96
Various fruit gathering devices are important part of tree shakers used in fruit harvesting. The catching surface is generally used in the form of a stretched thin sheet interacting with the falling fruit. This interaction depends on many factors such as the shape and mass of the fruit, the falling height and the mechanical properties of the catching material.
In recent investigation different canvas, composite and silk materials were selected and their mechanical behavior was experimentally determined. Using the energy conservation principle, the main impact characteristics of the falling fruit was derived and used. Static and dynamic loading tests were carried out using spherical intenders and artificial fruits. Investigations have shown that, using the appropriate material characteristics, the catching surface can serve as a cushioning material and it can considerably reduce the impact stresses in the falling fruits.
Stress physiology of palm trees II. The effect of heavy metals and high irradiance on the photosynthesis of palm Trachycarpus fortunei84-88.Views:147
A study was carried out to analyse the individual and combined effects of heavy metal toxicity and high irradiance on the photosynthetic characteristics of young, fully expanded leaves of palm seedling Trachycarpus fortunei under laboratory conditions. Heavy metals were found to inhibit both the light and dark reactions of photosynthesis and the inhibition was more affected in the light than in the dark. Single photoinhibitory conditions caused a 60 % decrease in the electron transport activity after 120 min of light exposure which was completely reversible in the dark. In contrast, the combined effect of high light and heavy metal treatment resulted in a 90 % decrease in the activity, but no reversible recovery in the dark could be detected. This indicated that the simultaneous effect of these two stress factors led to irreversible damages of the photosynthetic machinery and as a consequence caused the general destruction of the plant.
Abbreviations and symbols: Fo: initial chlorophyll fluorescence; Fm: maximum total fluorescence; Fv: variable fluorescence; AFi: intermediate level of fluorescence induction; PSII: photosystem 2.
Evaluation of elder (Sambucus nigra) varieties and candidates for the canning industry. Results of the composition studies102-107.Views:140
Sambucus nigra is a very common elder species in Europe. Due to its excellent composition, natural dye content and healing power it can be considered as a biological active plant. In Hungary the cultivation of Sambucus nigra started in the nineties and since that time there is a growing demand for this plant. Sambucus nigra is a special fruit due to its sole.-application for processing industry. Partly fruit products are made of it, partly it is used as a natural dye. In both cases the first step is the knowledge and evaluation of the composition of the various elder varieties and candidates. For that reason composition studies of different elder types were performed in several years at the Department of the Canning Technology of the Szent Istvan University.
The most important sample was the Haschberg variety, which is the sole elder type accepted and allowed for propagation by the government. This plant is grown in the Pilot Plant of the Szent István University in Szigetcsép. Among the studied samples there were some varieties cultivated in the Fertőd Research Station. They were the following types: No. 33, 480 and 481. Besides elder collected wild in Szigetcsep and the very promising early-ripened SZ-CS 21-23 variety originated also from Szigetcsép were investigated. One year it was possible to study the Sambu variety, too. Department of the Fruit Culture of the Szent István University helped to obtain the various elder types and candidates. Along our experimental activities, the following components and parameters were studied: the content of pectin, organic acid, carbohydrate, mineral, vitamin C, total acid, aquesoluble dry material, anthocyanin and the pH.
After having obtained a juice, a concentrate from the species has been made and — after freezing — the aquesoluble dry substance and the acid content, as well as the colour parameters were monitored. Studies were performed in two years (1997-98). On the basis of these results classes were established for all compounds, from which an overall ranking was derived.
It was found that in both years the Haschberg variety proved to have the best composition. Therefore regarding to the overall series of order the experiments performed in the second year supported the results obtained in the previous year. Results have shown that Sambucus nigra has excellent composition beside its curative effect. Its mineral content has surpassed that of the other fruits and it had advantageous acid-and carbohydrate composition. The ascorbic acid content of the Haschberg variety is striking. It can be concluded from the experiments that the Haschberg type has the most advantageous composition, therefore it is suitable for making special curative and exclusive products.
Flavonoids, chalcones and phenyl-propanoids in apple and pear flowers35-38.Views:133
The presence of phloretin-glycosides in the hypanthium and pistil of apple and pear flowers can be verified. Thin layer chromatography is a reliable method for detecting phloretin, gained by acidic hydrolysis. The dominance of phloretin was equally characteristic for flowers in apple (`Sampion', 'Freedom') and pear (Tem-re Bosc', 'Conference') cultivars treated with various bioregulators (Biomit, Bion 50WG, Regalis), no significant difference could be found visually as compared to control samples. Chlorogenic acid and caffeic acid was detected in all apple and pear samples, rutin was present only in pear, and hyperoside was found only in a few apple samples.
Evaluation of essential oils by gas-chromatography and a new method: "electronic nose"85-89.Views:138
The chemical quality of the essential oils is determined by their composition as well as by the complex aroma features. For the evaluation of odour and aroma, sensory tests are practised, especially for applications such as aromatherapy, food industry or perfumery. In the recent studies we investigated eight Mentha origins (populations of Mentha iperita, M. spicata and M. arvensis) of our genebank collection using a new and effective instrumental sensory evaluation method parallelly with the usual GC analysis.
The results show that the examined mint clones possess different essential oil accumulation levels and special flavour characteristics, too. The GC analysis of the essential oil revealed characteristic differences at both inter- and intraspecific level in the proportion of mentol, menthon, carvon, limonene, menthyl acetate and in two not identified monoterpenes.
In the sensory tests the special complex aroma enables a reliable distinction with a single exception among the populations by the help of the "electronic nose" equipment. The distinction among the samples based on the sensor signals of the instrument — evaluated by multivariate methods — shows a close relation with the detected monoterpene components of the essential oil.
Reaction of different Capsicum genotypes to four viruses61-64.Views:145
The objective of this study was to examine the reaction of 44 Capsicum genotypes to common strain of Tobacco mosaic virus (TMV-C/U1), Obuda pepper virus (ObPV), NTN strain of Potato virus Y (PVYNTN) and legume strain of Cucumber mosaic virus (CMVU/246). Reaction (extreme resistance, hypersensitive reaction, latent susceptibility, susceptibility) of the tested Capsicum species/hybrids and breeding lines seemed to be greatly depending on hosts and viruses. Out of the breeding materials 4/99 F2 and IX-8 in to CMV-U/246, while 32.Bogyisz. type, VI-57 ii. 57/83 and V-12=19/98 to TMV-C/Ui showed extreme resistance. Two lines (V-25 F1=32/98 F1 and V-27 in F4=35/98 F4) showed hypersensitive reaction to ObPV. Latent susceptibility to PVYNTN was observed in case of all eleven tested Capsicum genotypes and in case of several lines to TMV-C/U1, ObPV and CMV-U/246. Other breeding materials proved susceptible to the mentioned viruses. Pepper genotypes showing extreme resistance and hypersensitivity could be used for resistance breeding to viruses.
Polyphenol- and anthocyanin content changes effected by different fermentation- pressing and aging technologies65-67.Views:169
Different grape processing, fermentation and aging technologies were compared in our study on the white wine-grape variety Grüner Veltliner between 2012 and 2014 in Hungary,Cserszegtomaj. The vines are grown on brown forest soil on dolomite bedrock, stocks were planted 3x1 m row and vine space, respectively in our experimental area. The soil has slightly alkaline pH, the orientation of the vine rows are East-West. The training system is modified Guyot cordon, with 1 m trunk height and cane pruning method. After the harvest half of the yield has been put into the de-stemmer crusher before pressing while the other half has been pressed immediately (whole bunches). From the filtered and bottled wine anthocyanin, and polyphenol content was measured in 2013 and 2014. Another enological technology testing experiment has been set on aging of Grüner Veltliner in 2013. The wine was fermented with addition of fine lees from juice sedimentation. Traditional (racking only), battonage and fast ready-made aging technologies have been set together, each treatment in three replicates were observed.
Experiments on the Resistance or Pepper Cultivars to Macrophomina phaseolina74-75.Views:119
The ashy stern blight of pepper (Capsicum annuum) is often caused by Macrophomina phaseolina. Serious wilt disease occurred between 1994 and 1996 of pepper plants in Hungary. In 1996-98 screening experiments were made on many pepper cultivars. Culture (Knopp) solution experiments, pot experiments, greenhouse and field trials were carried out. We determined the incidence of disease by visual examinations, testing on PDA culture, and light microscope. There were significant differences in susceptibility of cultivars and breeding materials.
Study on the viruses of Petunia in Hungary55-59.Views:118
Virus susceptibility of 11 varieties of vegetatively propagated petunia against 2 virus strains (TMV-C/U1 and PVYNTN) were examined. Neither resistant nor tolerant varieties of petunia were found. The virus infection of the Petunia genus was examined in Hungary. The most common pathogens were the Tobacco mosaic tobamovirus (TMV) and the Tomato mosaic tobamovirus (ToMV), but the samples also contained Alfalfa mosaic alfamovirus (AMV), Cucumber mosaic ClIC11171014171S (CMV) and Potato Y potyvirus (PVY). Potato X potexvirus (PVX) was isolated in the varieties of trailing petunia for the first time.
Effects of different rootstocks on the morphologic parameters of watermelon grafts during transplant production69-73.Views:159
Before Hungary joined the EU watermelon production was a key sector of the Hungarian vegetable industry. Its production area shrank by nearly 60 % since 2004, it is only 5000 ha today. Stable and reliable market failed to evolve in the last years and extreme weather events occurred more frequently. An unfavourable growing season can notably affect the production volume of the next season. Information gathered in the last years support the assumption, that suitable stocks can help eliminate the issues caused by extreme weather or short-term crop rotation. Choosing the right grafted or non-grafted transplant is not enough any more, growers also have to select stock. In fruit and vine production choosing the stock, which is the most suitable for the technology is evident and this approach should be widely adapted by watermelon growers as well. In this research we investigated the growth parameters of different watermelon stocks and their effect on the scion during the transplant production. Measurements were carried out on seven different stock-scion combinations of the scion ’Topgun F1’ hybrid. Two of the stocks were interspecific (Cucurbita maxima × Cucurbita moschata) and five stocks were Lagenaria-type (Lagenaria siceraria) stocks. We made and recorded observations of the transplants’ length (cm), diameter of the stock and scion (mm), number of leaves (piece), root length (cm), root mass (g) and shoot mass (g). We concluded that early pricking out of transplants with interspecific stocks is successful due to their hardiness and vigorous growth. The effect of the ’Shintosa camelforce F1’ interspecific stock was outstanding. Furthermore, the results confirmed the practical observation that the root system of interspecific stocks grow vertically more allowing them to take up water and nutrients from lower soil layers in poor sandy soils. From the Lagenaria group the root system of the ’DG-01 F1’ was similar to the interspecific stocks’. It can be grown even in sandy soil, however other Lagenaria-type stocks are more suitable for production in hard soils with nutrient supply because of their compact root system. This study can serve as a basis for further research in the topic that can conduce to site- and technology-specific stock selection.
Virus susceptibility and resistance of Hungarian pepper varieties68-73.Views:151
The aim of our study was to examine susceptibility or resistance of 18 pepper varieties to four viruses [tobacco mosaic
tobamovirus (TMV), sowbane mosaic sobemovirus (SoMV), NTN strain of potato Y potyvirus (PVYNTN) and cucumber mosaic cucumovirus (CMV). Out of the 18 varieties, 13 were resistant to CMV infection. Thirteen varieties were susceptible to TMV, while five ones (Dabora Fl, Brill Fl, Feherozon Synthetic, Ciklon Fl, Cecil Fl) showed only local hypersensitive reaction. All of the tested pepper varieties showed resistance to SoMV. Eight varieties (Tuba, Fehérözön Synthetic, Boni, Alba Regia, Korona, Édesalma, Cecil Fl, Star) were found to be resistant to PVYNTN. Out of the examined varieties five (Boni, Alba Regia, Korona, Édesalma, Star) were resistant to three viruses (SoMV, CMV and PVYNTN). Only one (Cecil F1) displayed complex, extreme resistance to SoMV, PVYNTN, CMV and hypersensitive reaction to TMV, therefore this hybrid is very important in pepper breeding and growing for virus resistance.
Mass and displacement relationships of tree shakers36-40.Views:105
The degree of mechanically harvested fruit removal by shakers is determined by the displacement pattern, the frequency and the amplitude of shaker mechanism attached to the tree trunk. The displacement pattern is derived from the structural setup of the vibration mechanism, the frequency can easily be adjusted by the rev/min (rpm) of the rotating masses. More problems are arising in determining the dynamics of the tree-shaker system. Among others the amplitude of the attachment point and its components, the effective masses reduced to the attachment point.
Recent work gives some new insight into the tree-shaker dynamics including new calculation methods to determine the displacement components and the effective masses reduced to the attachment point. A fully new approach is given to include the vibrating soil mass into the total effective mass. The assumptions are supported and verified by laboratory and field measurements.
Heat waves in Hungarian plant production113-118.Views:174
A 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.
Pollen viability of ‘Besztercei plum' clones depending on the effect of the year115-121.Views:144
The 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.
Sensory analysis as a supporting method for marjoram breeding73-77.Views:180
Marjoram is one of the most important spices in Hungary, which is utilized both in phytotherapy as well as in alimentary industry. Organoleptic quality of the drugs of two Hungarian varieties of Majorana hortensis /'Francia' and 'Magyar'/ were investigated by two different methods of sensory analysis. The chemical composition of the material was checked by GC analysis of the distilled essential oil. Although their main compounds and proportions showed similar patterns, both the human and instrumental sensory tests based on the complex odour and aroma of the drug, proved a significant differentiation of the two varieties.
On the basis of our results, sensory evaluation may be a useful tool in the practice in determination of complex aromatic values of marjoram, as a spice. At the same time it seems to be a suitable method in promotion of breeding efforts.
Changes in the population density of the horse-chestnut leafminer, Cameraria ohridella and of its parasitoid community at Hédervár during 7 consecutive years (1998-2004)65-73.Views:162
Studies available up to now usually report changes in populations of Camel-cola ohridella and its parasitoids in a period of 3 years or shorter. Due to the limited duration of investigations, no tendencies of changes could be disclosed and, according to the general idea, the infestation level of the horse-chestnut leafminer and the rates of parasitism do not change significantly. Based on our examinations carried out throughout 7 consecutive years we suggest that the infestation level of C. ohridella is generally decreasing and the rate of parasitism is increasing. A possible adaptation of the parasitoids to this new host is showed on the changes of parasitism. In contradiction with earlier studies, authors assume that a partially stable permanent parasitoid community is being developed around the horse-chestnut leafminer. Proportions of adult moths and parasitoids hatched in the same year of sampling or the next year were determined.
Influence of soaking periods and temperatures on germination and respiration of pea seeds69-71.Views:171
Samples 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.
Atropine and scopolamine in leaf and flower of Datura arborea L.61-64.Views:218
Angel's trumpet (Danira = Brugmansia arhorea) is a common, popular ornamental plant in Hungary. On the basis of thin layer chromatographic and densitometric alkaloid studies of leaf and flower samples collected from several places in Somogy and Baranya counties it can be stated that in samples of cultivars with different flower colour, taken approximately at the same time, the atropine and scopolamine content varies: there are samples free of alkaloids, but most of them are rich in alkaloids. Although the means do not reflect the extremes, they are suitable for determining the alkaloid accumulating capacity of flowers. Generally the amount of atropine and scopolamine is significant both in the leaf and the flower. It is conspicuous that the flower can be characterised by an extremely high scopolamine content (mean in mg/g dry matter of leaf: atropine 0.34, scopolamine 0.31; of flower: atropine 0.26, scopolamine 0.85). Thus it can be stated that the leaf, and especially the flower of angel's trumpet is a potential hallucinogen, just like in the case of Datura stramonium.