Search

Search Results

• The influence of nitrogen-fertilizer and harvest time on the productivity of Thymus vulgaris L.

  43-46.

  R. Omidbaigi

  A. Rezaei Nejad

  Views:

  256

  The influence of nitrogen-fertilizer applied in 0, 50, 100 and 150 kg/ha dosages, as well as the time of the harvest carried out in full flowering and early fruit set stages were studied on the herb and essential oil production of garden thyme (Thymus vulgaris L.). The small plot experiment was installed in the Experimental Field of Tarbiat Modarres University near Teheran, under sandy loam soil conditions. On the basis of the results the nitrogen-fertilizer had a significant effect on the dry-matter production of the species: the herb yield, calculated on one hectare, increased from 671.88 kg up to 1021.00 kg value as a result of 150 kg nitrogen dosage. The essential oil yield proved to have a similar tendency because neither the accumulation level of essential oil, nor the ratio of thymol were effected by the nutrient supply. Analyzing the effect of harvest time changes in both dry-mass production and essential oil accumulation were observed. The highest herb yield (1238.20 kg/hectare) was obtained in early fruit set, when about.50 per cent of fruits reached their full size in the inflorescence. The accumulation level of essential oil also reached its maximum at the sane development stage, showing 0.75 per cent value, which is about two fold higher comparing to the accumulation level was measured at the time of full flowering (0.41 %).

• The quality and storage efficiency of some apple varieties as a function of picking date, area of production and duration of storage

  99-103.

  P. Sass

  Z. Lakner

  Views:

  156

  Numerous apple varieties have been tested parallel with traditional Jonathan varieties during four years, 1990-1994 on three different geographical areas of Hungary. The picking time took place at three different times in a year: ten days before the probably optimal picking time, at close-to-optimal picking time, and ten days after the optimal picking time. The effect of storage on quality of fruits have been tested in February, March, and April under circumstances of a semi-industrial storage experiment.

  The results of experience can contribute to answer numerous current, from point of view of practice important topics:

  • The stochastic relations between various fruit quality parameters at different varieties
  • The change of fruit — quality during storage
  • The effect of different picking date on storage losses
  • The possibilities of storage — loss predicting by the utilization of multiple regression analysis.

  The most important results of experiences are as follows :

  1. The starch — degradation test and Streiff — index are well applicable for practical purposes to determine the optimal harvest-date.
  2. On base of analysis of various losses and physiological diseases the high importance of mass loss is obvious. In the variety Jonnee the earlier picking date considerably increased the mass loss. The effect of variety on mass loss is rather limited. In the Jonathan varieties the Jonathan spot was a rather important physiological disease. The late picking time increased the frequency of Jonathan - spot. At optimal date of harvest at Jonnee the frequency of Jonathan -spot was lower, than at Jonathan M 41. In the Jonathan M41 and Jonnee the importance of scald was rather limited, but in the Wellspur Delicious and Smoothee this disease occurred relatively frequently. In the Smoothee the earlier picking time considerably increased the probability of scald.
  3. The multiple regression analysis yielded reliable results, fit for prediction of storage losses and diseases on the base of chemical and physical properties, determined at the time of picking.

   

• The antioxidant capacity of sea buckthorn (Hippophae rhamnoides L.) berries depends on the genotype and harvest time

  27-29.

  N. Makovics-Zsohár

  A. Hegedűs

  É. Stefanovits-Bányai

  R. Rédei

  N. Papp

  Views:

  313

  Berries of sea buckthorn (Hippophae rhamnoides L.) are characterized by increasing popularity due to their presumable healtheffects. The aim of this study was to compare the antioxidant capacity and total polyphenolic content in the berries of six Hungarian grown sea buckthorn genotypes and characterize the genetic variability in this trait. The harvest time of sea buckthorn berries affects the antioxidant capacity and total phenolic contents in berries of three popular cultivars of German origin. Berries harvested in October had higher antioxidant capacity compared with those harvested one month later. The extent of the difference was genotype-specific. Our analysis revealed a nearly 3-fold difference between the lowest and highest antioxidant capacities of the 6 tested genotypes with ‘Leikora’ showing the highest ferric reducing antioxidant power and total phenolic content. The TEAC values ranged between 1.76 and 3.13 mmol Trolox/100g fresh weight with Pető 1 and ‘Frugana’ having the highest values. The results presented in this study demonstrated that Hippophae rhamnoides berries possess in vitro antioxidant activity strongly determined by genotype but also influenced by harvest time.

• Effect of the terroir and the harvest time on the Kékfrankos grape berries sensorial properties in Eger (Hungary)

  87-92.

  Z. Barócsi

  Views:

  197

  In this research the effects of the production site “terroir” and the harvest time on the most important organoleptic properties of the berries of Kékfrankos (Blaufrankish) grape variety were observed. The follow-up of the maturation process in a given parcel can effectively supplemented by the results of sensorial evaluations of the grape berries. In most cases, the tasters found significant differences in sensorial characteristics of the berries due to the harvest time, although the trends of each parcels were different. Significant differences were frequently found in the result of the observed terroirs.

• Effect of the terroir and the harvest time on the Kékfrankos grape berries visual and physical parameters in Eger (Hungary)

  81-85.

  Z. Barócsi

  Views:

  164

  In this research, the effects of the “terroir” and the harvest time on the most important physical properties of the berries of Kékfrankos (Blaufrankish) grape variety were examined in 2010 and 2011. The results of the experimentation shown, that the maturation processes can be well described by different physical parameters of the grape berry. The terroir and harvest time effects were investigated in two different vintages and four different territories. It can be concluded, that these physical parameters change significantly during the ripening period, but trends differ between vintages and regions.

• Alternate bearing of 'Golden Reinders' and 'Summered' apples

  77-85.

  J. Racskó

  J. Nagy

  Z. Szabó

  M. Soltész

  I. J. Holb

  J. Nyéki

  Views:

  274

  The aim of the present study was to study the effect of biennial bearing (irregular yields) on the generative production of apple cultivars 'Golden Reinders' and 'Summerred' on M.9 rootstock. The observations were made at Nagykutas in West-Hungary for four years. The authors have studied the flowering time, flower density, fruit density, fruit drop, seed content, yielding and fruit quality in the on-year and off-year. Based on the results, it can be stated that the alternation does not cause a significant change in the flowering time of cvs. 'Golden Reinders' and `Summerred': the difference between the flowering time of trees in the on-year and off-year period was 0-1 day. However, there were significant differences in the flower density. 'Golden Reinders' proved to have a weaker tendency to alternation similarly to the statements of the literature. Alternation (off-year) was observed only in three years from the studied four years. While in the case of `Summerred', strong alternation was observed in all four years. In fruit density, there were differences among the cultivars and among the different cycles of biennial bearing. Fruit density (and its opposite, fruit drop) changed inconsistently in the period between flowering and harvest. In the case of 'Golden Reinders' and 'Summerred' 2 and 4 fruit drop periods were detected, respectively. In the off-year, the different periods were less distinct, in most cases they were overlapping each other. The dynamics of fruit drop was related to seed content per fruit. The lower the seed number was, the higher the degree of fruit drop was. In both the high- and off-year cycles, the number of seeds in fruits on the tree and on the ground increased with time. In the yield parameters (fruit number, fruit load, yield efficiency), the differences were greater among the yields of trees in the high- and off-year cycles for 'Summerred'. The fruit quality parameters were greatly influenced by the fruit load of the trees in the different alternation cycles. In general, it can be stated that fruit mass, diameter and height were lower on trees in the on-year. A similar trend could be observed in flesh firmness, cover colour and dry matter content, but the differences were smaller. 'Summerred' was more sensitive to the differences in fruit load.

• Effects of nitrogen fertilizer application rate and time to first harvest on leaf area index; leaf nitrate content and yield of irrigated leaf rape (Brassica napus L. var. Giant)

  64-75.

  J. Masaka

  M. Chandiposha

  B. T. Makaure

  B. Mazina

  Views:

  265

  In Zimbabwe, smallholder cultivation of leaf rape is of considerable importance due to the increasing demand for the leaf vegetable from the rapidly increasing urban populations.  A two-season field trial was conducted in the Agricultural Practice Experimental Plots of the Midlands State University in central Zimbabwe. The objective of the study was to establish selected biometric responses of leaf rape to N fertilizer rates and time to first harvesting. Increasing the rate of N fertilizer application considerably improves the yield of fresh rape leaf; LAI and concentration of leaf nitrate. Delaying rape leaf harvest after N fertilizer side dressing can be used as a strategy to boost rape leaf yield for vegetable markets with high single delivery demand. When harvesting is deliberately delayed after N fertilizer application rape LAI are significantly increased. Delaying the first leaf harvests by 7; 14 and 21 days after N fertilizer side dressing amendments increases the content of nitrate in fresh rape leaves. Fresh rape yield can be more accurately predicted by values of rape LAI. Nitrate concentrations in fresh rape leaf is a poor predictor of rape yield under field conditions.

• Analyses of temporal dynamics of brown rot development on fruit in organic apple production

  97-100.

  I. J. Holb

  Views:

  200

  In a two-year study, yield loss and temporal dynamics of brown rot development caused by Monilinia fructigena (Aderh. & Ruhl.) Honey were quantified and analysed in two organic apple orchards (Debrecen—Pallag and Debrecen—Józsa). The first infected fruits were observed at the beginning of August in both years and both locations, except for one occasion when the first infected fruit was found at the end of July. Temporal disease development was continuous up to harvest time in both years and locations. In the two years, pre-harvest yield loss on the trees amounted between 8.9% and 9.3% at Debrecen-Pallag and between 9.7% and 10.8% at Debrecen—Jozsa by fruit harvest. Incidence of infected fruits on the orchard floor ranged from 32.4% to 43.2% and from 53.3% to 61.9%, at Debrecen—Pallag and Debrecen—Józsa, respectively, by fruit harvest. Analyses of temporal disease progress showed that the best-fitted mathematical function was the power function in both orchards and years. Both parameters of the power function clearly demonstrated that incidence of brown rot on fruit increased faster on the orchard floor than on the tree. Moreover, the disease increase was faster at Debrecen—Józsa in most cases than at Debrecen—Pallag. Our results indicated that the strategy of disease management, the ripeness of the fruit and the presence of a wounding agent played an important role in the yield loss and in the temporal development of fruit disease incidence caused by M. fructigena in organic apple orchards. Biological and practical implications of the results are discussed.

• Results of experimental storage of sour cherry (Prunus cerasus L.) fruit

  65-78.

  M. Soltész

  T. Szabó

  J. Nyéki

  H. G. Davarynejad

  Z. Aryanpooya

  Z. Szabó

  Views:

  296

  In utilisation of sour cherry cultivars, the paradigm has gradually changed in the sense that fresh consumption gained much more attention than before on a worldwide scale. Consequently, much more attention is paid to the problems connected with the storage, i.e. preservation of fresh fruit for direct consumption. It is a genuine interest of growers, traders as well as of consumers to be informed about the possibilities of preserving economically the fresh status for a longer period after harvest during the warm summer weather in addition to the lengthening of the harvest season by choosing cultivars of different dates of ripening. Recent results of purposeful experiments indicate that the storability of the fruit of 6 main Hungarian sour cherry cultivars is on the same level ('Érdi bőtermő, 'Debreceni bőtermő’, 'Újfehértói fürtos', 'Kántorjánosi', 'Éva', 'Petri'). The traditional conditions facilitated the maintenance of freshness over a 5-week-long period, and the loss of volume was less than 7%. During the first 2 weeks, there was no difference between the cultivars regarding loss of volume and decay, moreover, the effect of time elapsed after harvest and of adversities of transport was not significant. It could be stated that 2 week of storing is safely feasible. We need only 2 ^°C temperature and 90% of relative humidity. The relations of oxygen and CO₂ of the atmosphere is less decisive than temperature alone. No essential difference has been registered between the storing in plastic trays versus plastic boxes either. A study was performed to assess the modified atmosphere packaging (MAP) effect on Hungarian sour cherries growing in Iran (`Érdi bőtermő and ‘Érdi jubileum') shelf life. The harvested fruits stored at 0 °C under modified atmospheres (15% 0, and 10% CO₂ and 75% nitrogen) for 6 weeks. Descriptive analysis showed that sour cherry stored in control condition had a higher deterioration rate than those stored in under modified atmosphere, which showed a lower rejection rate and a longer shelf life than those stored in modified atmosphere.

• The effect of the method and the timing of the propagation on the growth, earliness and productivity of sweet corn

  134-139.

  S. Hodossi

  A. Kovács

  E. Besenyei

  Views:

  188

  Direct sowing in 16 cm deep trench covered with perforated plastic sheet (for 3 weeks), transplant using, and uncovered direct sowing (control) was tried on 2 locations, with 2 varieties (very early Kecskeméti korai extra, and middle early Kecskeméti SC-370) in Szarvas on loamy soil, and in Kecskemét on sandy soil in 1996 — after a preliminary trial concerning perforated plastic covered trench sowing in Szarvas, in 1995.

  The plant height (weekly), the average leaf number/plant, the total leaf area (once), the total yield, the quality of cobs, and the earliness was measured. The results are:

  1. Kecskeméti korai extra during the first 6 week period the transplanted plants were the highest, but from the 7th week the plants which were sown in trench and than were covered with perforated plastic sheet (for 3 weeks) were the highest.
  2. SC-370: The transplanted plants were the highest-until the end of plant height development.

  The plant height development stopped at the 9th week of the measurement by early, - and stopped at the 10th week by middle early variety. The average leaf number/plant varied between 9,25-10,50 and was not influenced either by variety or by the treatment. The total leaf area was (on 5th of June) the largest by transplanted plants, which was followed by plants that were sown in trench and then were covered with perforated plastic film (for 3 weeks).

  2. The highest yield was observed by plants, which Were sown in trench, and then were covered with perforated plastic film (for 3 weeks). Transplanted plants followed it.
  3. Quite the total yield (98,3%) of transplanted Kecskeméti korai extra variety plants were harvested on 4th July. 89% of the total yield was picked up of trench sown and then with perforated plastic covered plants. The harvest of uncovered control started on 15th July. The harvest of transplanted SC-370 plants started 19th July, when more than half of the total yield (57%) was picked. The uncovered control was harvested 29th July.
  4. The weight and the measure of cobs generally were not influenced by the treatments, but the average weight of the cobs of the transplanted Kecskeméti korai extra plants (0,21-0,18 kg) are less than the, requirement.

   

• Relation between the germination and infection ratio on Sida hermaphrodita L. Rusby seeds under hot water treatment

  117-121.

  E. Kurucz

  P. Szarvas

  M. G. Fári

  Views:

  210

  Sida hermephrodita or virginia mallow is a perspective perennial herb in the Malvaceae family able to yield a biomass crop through between ten and twenty years. Additionally, the plants have a lot of uses and benefits for instance it can use it as a fodder crop, honey crop, ornamental plant in public gardens. It has favorable features like fast growing and resistance against the disease and climatic fluctuations, etc. Sida is in base stage of domestication therefore has a serious disadvantage the low and slow germination as a big part of wild plants. Due to the expressly low germination percent the need of seed showing of driller is should tenfold, 200 thousand seed/acre instead of 10-20 thousand what is not available and expensive Therefore practical purposes of our research of seed physiology was to increase the seed germination percent in a disposable ,basically wild Sida population. We examined two factors relating to seed germination percent and seed germination power during our research: the influence of hot water treatment and the effect of exogenus or endogenus infection of seed. However, in our germination tests, utilizing scarified seeds with hot water (65, 80 and 95 oC), 29,33 to 46% germinated of the seeds collected from the population of S. hermaphrodita in Debrecen. The average germination for all season was 5-10 % wihitout treatment and rised using hot water up to almost 50%. When physically scarified used, the oldest seeds showed the best germination (46 %) after the hot water operation in spite of the previus studys (Spooner 1985; Chudik et al. 2010; Doliński R. 2009.). We discovered that there are a distinguished close relationship between the seeds collecting time and the infection, as well as germination percentage. Thus, 2009 season was the most favourable in case of contamination (control:17,33 and 80 oC treatment:0%) as well as germination percent. It could be concluded that, the best season for our findings was 2009 due to autumn harvest of Sida seeds. In our oppinion, the autumn harvesting should be the best time to overcome the problem of the low germination and high infection percentage.

• Evaluation of generative accomplishment of new apple cultivars in Hungary

  11-15

  Á. Csihon

  I. J. Holb

  I. Gonda

  Views:

  336

  In a two year study, 14 new apple cultivars (cvs ’Gala Venus Fengal’, ’Gala Decarli-Fendeca’, ’Galaval’, ’Jugala’, ’Gala Schnitzer (S) Schniga’, ’Red Cap Valtod (S)’, ’Early Red One’, ’Jeromine’, ’Crimson Crisp (Co-op 39)’, ’Red Topaz’, ’Wilton’s Red Jonaprince’, ’Red Idared’, ’Fuji September Wonder’ and club cultivar) were studied in Eastern Hungary at Nyírbátor. The following parameters were measured: trunk cross sectional area (cm2), harvest time with yield (date, kg/tree, number/tree), fruit size (mm), fruit surface color (%), and color intensity of the fruit surface (1-5). According to our two year assessments regarding, the best generative accomplishment was achieved for the cvs ‘Gala’ sorts trained to slender spindle and the cv ‘Red Jonaprince’ trained to super spindle. According to the trunk cross sectional area the ‘Gala’ sport trained to slender spindle showed the strongest growth among the 4 years old trees, while the cv ‘Fuji SW’ and the cv ‘Jeromine’ presented lower vegetative accomplishment. The ripening time of the cultivars started at the end of August and finished at the beginning of October. ‘Gala’ mutants trained to slender spindle provided the highest yields. Fruit size of all cultivars reached the market required standard, however, cvs ‘Red Jonaprince’ and ‘Red Idared’ produced large fruits over 90 mm. The fruit size of the ‘Gala’ sort was 72–75 mm. Most of the cultivars showed high fruit surface color and color intensity.

• Storage ability and differences of carrot varieties defined by firmness changes measured with new non-destructive acoustic method

  37-40.

  S. Istella

  V. Muha

  I. Terbe

  Views:

  189

  Carrot production in Hungary is getting more important these days. The condition of the quality insurance is to choose the proper variety of carrot and store on optimal conditions therefore measuring firmness and matter parameters are very important. Four varieties of carrots were measured (Bangor, Olympus, Napa and I3olero). The roots were stored in unsealed polyethylene bags at 4-10 degrees Celsius and 95% relative humidity. The vegetables were measured three times: at harvest, after I .5 months of storage and after four months of storage. The samples were tested by non-destructive acoustic. Stillness measuring method during the 112 days experiment for firmness. In laboratory were measured weight loss, dry material -NO3 and sugar content as an important matter parameters.

  The firmness change as a function of storage time are the following: First part of the storage (after 60 days), the Napa variety changed least in the case of acoustical parameter, at the same time its weight Foss and dry material content were not rise significantly, while its sugar content increased with 50%. The l3olero variety had the highest changes of sugar content during storage. During the second storage period, the softening speed of all samples was increased. The Bolero had the highest average mass loss (32,7%) and NO₃ content changes as well. All measurements showed the largest changes for the Bolero variety. The highest percentage of dry material content was found by the Bolero and Napa varieties (18-20%).

  In this experiment, we found that the Bolero variety showed the greatest loss in compressibility during storage. If both firmness and weight loss results are considered, the Napa variety is found to be the most storable variety in sort period. The Bangor variety was found to be the best for long-term storage.

• The effect of storage to optical properties in case of two apple fruit varieties

  33-36.

  A. M. El Shal

  P. Riczu

  A. Nagy

  E. Sulyok

  Z. Szabó

  J. Nyéki

  Views:

  286

  The keeping quality of fruits is a very important factor in storage point of view, since it could be elongated the consumption time of fruits. In many cases the storage may be necessary, e.g. in short time it is not able to market due to the rich harvest, or all fruits could sell in markets throughout the year. The keeping quality of various fruit species is greatly different; moreover it could be observed some differences between the varieties as well. In our research, we have investigated the spectral properties of the external surface and fl esh of two ripe apple varieties – Jonagored and Granny Smith – before and after storage (about 3°C and about three weeks). The hyperspectral investigation was carried out with AvaSpec-2048 Fiber Optic Spectrometer. The experimental results represented the differences between healthy and chilling injured apple fruits. Furthermore, some indices were created to given countenance to the spectral differences.

• The size of the canopy of sour cherry trees depends on the time of pruning

  49-52.

  I. Gonda

  Views:

  175

  The intensive culture of sour cherry is achieved by training of trees to form smaller canopies not by means of dwarfing rootstocks but by growth moderation techniques. The rootstocks traditionally used cause vigorous growth, and it is up to the technology to apply procedures less utilised earlier for that purpose. One of those techniques is the transfer of hibernal pruning to the estival period. The best term of the latter is the period of 1-3 weeks after fruit harvest.

  The prolongation of the period of favourable illumination and the reduction of the canopy size facilitate higher densities of planting (number of trees per hectare) and a better exploitation of the crown (specific yield). The regular use of summer pruning resulted also in a better quality of fruit.

• Morphological and phenological properties of sour cherry varieties grown in Hungary and their inter-incompatibility relations

  114-117.

  J. Nyéki

  Z. Szabó

  T. Szabó

  M. Soltész

  Views:

  220

  Regular observations and experiments were performed during a 14 year period on 6 sour cherry varieties. The morphological traits of leaves and fruits were compared, and the phenology of blooming as well as of ripening dates served to start an estimation of the possibilities of mutual pollination and the planning of harvest operations. Experiments involved obligate autogamy, artificially controlled allogamy and open pollination in order to reveal self-fertility, self-sterility or inter-incompatibility relations.

  The varietal characters represent, each, different values in the distinction of the items, because of their intra-varietal variability. From that point of view, the most reliable are the data of blooming and ripening time, fruit size and the fertility relations.

  Inter-incompatibility was observed between the group of self-fertile, "Pándy type" varieties (`Újfehértói fürtös’, ‘Debreceni bőtermő’, ‘Kántorjánosi’) on one side and the selection of Pándy 7', a self-sterile variety on the other side. Unilateral incompatibility has been detected within the former group of new, self-fertile varieties, the combinations: (`Újfehértói fürtös’ x ‘Debreceni bőtermő’ as well as `Újfehértói fürtös’ x Kántorjánosi’.

  Our results prove the close kinship between those three new varieties and the original Pándy variety on the base of being highly similar in their morphology and also of the fact of their inter-incompatibility, though unilateral.

   

• Apricot fruit chilling injuries during the cold storage affected by harvest maturity

  28-31.

  A. Ezzat

  Views:

  251

  The study aimed to find the effect of different maturity classes (up to the days after full blossom) on the post-harvest life of 3 different apricot varieties Gold Cot, Bergarouge and Flavor Cot in Hungary. The fruit harvested in a particular time 65, 75 and 85 days after full blossom and divided to three maturity classes (Class 1, 2 and 3, respectively). Fruit stored in cold storage for 7 days at temperature 1 °C. Fruits were investigated in regard to physical parameters (weight loss, fruit firmness and soluble solid content SSC) and chilling injuries. The results showed that the varieties followed different ways in regard to response to different maturity classes. The maturity class I for all the tested varieties recorded the lowest weight loss, while with the increasing maturity stage the weight loss percentage for all the varieties recoded high values. The firmness decreased with delayed harvesting for all the varieties. Data of the chilling injuries showed that all the fruits which harvested at maturity I, recorded the highest percentage of fruit with CI (chilling injuries) at 0 (48.5, 37.25 and 38.75%) and CI class I (44.75, 35.75 and 39.75%) for Bergarouge, Gold Cot, and Flavor Cot.

• Changing of inert content values of apricot varieties

  39-41.

  Sz. Németh

  G. Ficzek

  M. Stéger-Máté

  G. Sándor

  Gy. Végvári

  E. Kállay

  M. Tóth

  L. Szalay

  Views:

  199

  The consumers have been exigent increasingly about excellent quality. The speci fie flavour and fragrance of apricot evolve during ripening. We need to be acquainted with changing of inert content during ripening to the choosing of optimal harvest time. The Regional University Knowled ge Centre -Research and Development in Foodstuff Chain project had presented an opportun ity to study the inner content of apricot. Our aim was to study evaluation of health care attributes of apricot fruit. We investigated different ripeness samples of four apricot varieties ('Mandulakajszi', 'Pann 6nia', 'Gonci magyar kajszi'. 'Harcot') in our study of 2007-2009. Samples were taken the orchard of Sóskútfruct Ltd. Hungary. We had measured the water soluble antioxidant capacity, polyphenol-, f3-carotene content and the dissimilar sugar­ and acid-fractions during ripening. We had experienced significant different in inert content between varieties.

• Epidemiology of brown rot on two apple cultivars in an organic apple orchard

  49-52.

  I. J. Holb

  J. Gáll

  Views:

  211

  In a two-year-study, the temporal development of brown rot (Monilinia fructigena) on fruits was analysed in an organic apple orchard on an early (Prima) and one late (Idared) maturing cultivars at Debrecen-Józsa in Hungary. Out of five mathematical functions (linear, exponential, three-parameter logistic, Gompertz, Bertalanffy-Mitscherlich), the three-parameter logistic function gave the best fit to brown rot incidence of all cultivars in both years. Disease progress started at the end of June for cv. Prima and at the end of July for cv. Idared, then disease increased continuously from 6-8 weeks up to harvest in all cultivars. Descriptive disease variates derived from the three-parameter logistic function were used to analyse disease progress. These were: Yf, the final disease incidence; Y55, fruit incidence at day 55; Y95, fruit incidence at day 95; b and q, the relative and the absolute rate of disease progress, respectively; T1.5, the time when disease incidence reaches 1.5 %; M, the inflection point and AUDPC, area under disease progress curve. Descriptive disease variates were significantly different (P<0.05) for cv. Prima compared to cv. Idared, except for the relative and absolute rate of disease increase, b and q, respectively. The largest differences among cultivars were in the values of the AUDPC. Disease progress curves and descriptive disease variates were presented and the practical implications of the results were discussed.

• The effect of pre-fruiting temperatures on the yield of Pleurotus strains

  49-51.

  A. Somosné Nagy

  A. Kovács

  Views:

  166

  Authors studied the effect of different temperatures prior to fruit body appearance on the yield of 3 Pleurotus strains P70, HK35 and 357. After 17 days of incubation at 25 °C and 28 °C the substrate blocks were kept for 7 days at 13, 16, 19, 22 and 25 °C. Then temperature was reduces to 16 °C during harvest time. Tests showed difference of some degrees in the optimal prefruiting temperature requirements of the strains which could result in even in 10-15% surplus yield. It is advisable to use technologies specially adapted to strains.

• Dynamic analysis of a simple fruit tree structure model

  53-55.

  Z. Láng

  Views:

  132

  The effect of shaker harvest on root damage was studied on a simple tree structure model. Equations were set up to be able to calculate the relation between shaking height and stress in the roots. To get the strain at break data field experiments were carried out. The acceleration versus time curves were recorded on different heights of the stem. Evaluating measured and calculated data it can be concluded, that the risk of root damage increases when

  • the height of shaking is decreased,
  • the stern diameter is smaller, and if
  • the unbalanced mass of the shaker is increased.