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  • The role of pruning in the intensification of plum production
    83-86.
    Views:
    478

    In an orchard planted in the spring of 1997, four kinds of spacing have been applied (4.0 m x 1.5 m, 4.0 m x 2.0 m, 5.0 m x 2.5 in and 6.0 m x 3.0 m). Four cultivars (‘Cacanska lepotica', Stanley' ‘Bluefre' and ‘President') grafted on Myrobalan rootstock were studied in the experiment aimed to explore the performance of plums under different spacing and training conditions.

    It could be stated that the trees grown on vigorous rootstock are prone to be cultivated much more intensely (smaller tree size, higher tree density) by the consequent use of green pruning technique. The most favourable economic combination (yield and labour costs) was found to be: 4.0 in x 2.0 in and 5.0 x 2.5 in (800-1200 tree/hectare), whereas the most adapted was the cultivar: 'Stanley'.

  • Evaluation of hot pepper (Capsicum annum L.) varieties for green pod yield and quality under rain fed production at Teppi, South Western Ethiopia
    45-49.
    Views:
    383

    The trials were designed with three replications in a randomized complete block design in order to evaluate the phenological, growth and yield potential of hot pepper varieties such as ‘Mareko fana’, ‘Melka Zala’, ‘Melka Awaze’, ‘Melka Shote’ and local check. Significant difference was observed between growing year and used varieties. The varieties also performed significantly different (p<0.05) for most of the considered traits in the study. The result revealed that varieties ‘Melka Zala’, ‘Mareko fana’ and ‘Melka Awaze’ were scored highest green pod yield of 8.39, 8.71 and 11.39 ton per hectare, respectively. However, ‘Mareko fana’ variety was susceptible to disease attack as compared to other varieties. Therefore, promoting both ‘Melka Awaze’ and ‘Melka Zala’ varieties for widespread production for Teppi and the areas with similar agro-ecological conditions could contribute to boost the productivity of hot pepper. ‘Mareko fana’ could also be used for dry pod purpose due to its attractive color.

  • Participatory evaluation of tomato (Lycopersicon esculentum Mill.) varieties under irrigation conditions at Abergelle district, Eastern Amhara
    17-22
    Views:
    221

    Participatory on-farm evaluation of improved tomato varieties (‘Melka salsa’, 'Roma VF' and 'Kochero’) against the local tomato variety was carried out during the 2019/2020 growing season involving six farmers of Abergelle district, Eastern Amhara. The objective of the experiment was to assess the performance of different tomato varieties for the farmers, then to collect their feedback. Based on the actual and farmers’ preference data, the analysis underscores the better performance of improved tomato varieties over local varieties by most yield-related attributes. Average marketable fruit yields of ‘Melka salsa’, ‘Roma VF’, ‘Kochero’, and the local variety were 4.62, 3.88, 3.64, and 3.10 ton ha-1, respectively. The improved varieties thus had a yield advantage of 72.38%, 37.14%, and 25.72% over the local variety in that order. Among improved tomato varieties, ‘Melka salsa' provided the highest fruit yield on top of owing the highest score of overall preference attributes rank. Scale-wide diffusion of ‘Melka salsa’ tomato variety is therefore suggested for similar and potential agro-ecologies. Biological scientists also should take farmers’ preference attributes and feedback as a backup for future breeding and adaptation studies on tomato varieties.

  • Severely pollen-limited fruit set in a pear (Pyrus communis) orchard revealed by yield assessments and DNA-based paternity assignment of seedlings
    67-74.
    Views:
    339

    In commercial fruit tree orchards, consistently high yields are necessary for a durable economy. The Swedish pear cultivar 'Carola' has been noted for low setting in some orchards, possibly due to insufficient pollination. In this study, fruit set was evaluated in a research orchard where `Carola' had been planted together with four potential pollinators. Total yield and number of fruits was noted during three and four years, respectively. In 2003, seeds were germinated from the harvested `Carola' fruits, and the paternity of three seedlings from 50 trees was determined with RAPD analysis. 'Clapp's Favourite' had sired 39.6% of the seedlings, closely followed by `Seigneur d'Esperen' (30.7%) and 'Clara Frijs' (26.7%) whereas 'Skanskt sockerparon' only sired 1.1% of the seedlings. The remaining 2.3% appeared to have been derived by selfing. Pollen-limited seed set was indicated at surprisingly short distances; accumulated number of fruits on the `Carola' trees was significantly higher when separated by only 2 m from one of the two most efficient pollinators, 'Clapp's Favourite' or 'Seigneur d'Esperen‘, compared to trees 4—l0 in away in the same row. Number of viable seeds per fruit was also higher in fruits from trees immediately adjacent to the pollinators, suggesting an effect of improved pollination success. The importance of very short inter-cultivar distances for efficient pollen transfer became even more clear when comparisons involved the true pollination distances as determined by RAPD; the accumulated yields decreased linearly from 55 kg at a 2 in distance to only 17 kg at 13 m.

  • Effect of postharvest on the economic viability of walnut production
    28-38.
    Views:
    677

    In this study we were studying the question whether walnut production under domestic natural and economic circumstances shall be considered a profitable activity or not. Our partial objective is to determine, what level of natural inputs and production costs are required for walnut production, what yield level, selling price and production value can be attained, what level of profitability, rentability and efficiency may production have, is the establishment of a walnut orchard profitable on the entire lifespan of the plantation, and the production of which is more efficient: the dry shelled walnut production requiring postharvest activity or the raw, shelled walnut without postharvest activities. In this study, comparison of two systems is conducted. First version: producer establishes a walnut plantation and sells walnut raw and shelled. Second version: producer also invests into a drying facility, and in this case the end product is the dry, shelled walnut. If the producer sells walnut right after harvest in a raw bulk, total production costs in productive years reaches 974,011 HUF/ha. Attainable yield is 2.63 t/ha with 396.3 HUF/kg selling price, therefore the profit is 138,258 HUF/ha with 14.19% cost-related profitability. In the case when the producer sells dried, shelled walnut, production costs are 25% higher compared to that of raw walnut due to the cost of drying. By calculating with the postharvest loss, average yield is 1.84 t/ha, however, its selling price is way higher (882.84 HUF/kg), therefore the profit per hectare reaches 475,496 HUF with 39.01% cost-related profitability. Thus it can be stated that walnut production in an average year may be profitable even without postharvest, but efficiency is improved significantly when the producer sells the products dried. Investment profitability analysis revealed that production of raw, shelled walnut is not economically viable, since the plantation does not pay off on its entire lifespan (30 years), while walnut production with postharvest is efficient and rentable, since both net present value (NPV) and internal rate of return (IRR) showed more favourable values than in the previous case, and the orchard pays off in the 21th year after establishment.

  • The comparison of several soil cultivation methods in the Tokaj-wine region
    35-37.
    Views:
    344

    Our results show that the different cultivation methods have higher effect on the yield than on the grape quality. In 2007 the weather was extreme dry (from May to August only 195 mm precipitation was recorded) the straw mulch proved to be the best solution regarding the yield and the grape quality. Although no significant differences were observed in the sugar- and titratable acidity content of the must, the ratio of noble rotted berries was higher on the straw mulched plots. Straw mulch could conserve the moisture content of the soil and it seems to be contributed to the conformation of suitable microclimate for Botrytis infection, but for long distance conclusions further examinations need to be investigated. The less yield and ratio of rot was observed in case of barely covered vines and the vegetative growth of the grape was less intensive in case of these vines.

  • Production technology and fruit tree nutrition
    39-42.
    Views:
    372

    Fruit yield quality and quantity are effectively enhanced if healthy vegetative conditions are ensured. These optimal conditions — i.e. the balance between shoot development and yield — can be achieved by the rationalization of the production technologies, such as:

    • reduction of the size of the crown
    • adaptation of the severity and method of pruning to the conditions of the actual year
    • removal of the shoot tips
    • timely fruit thinning

    By establishing an improved level of plant nutrient uptake, this will ensure a healthy balance between shoot growth and yield.

  • Water relations of apple and influence on fruit quality (minireview)
    59-63.
    Views:
    543

    The saving of soil water content and the improvement of adaptability of plants to periodical insufficient water and use of deficit irrigation technology become more important because of the occurrence of frequently dry periods. The water use efficiency of apples can be increased by the choice of appropriate rootstocks and determination of water requirement of varieties that depend on their growing periods and climatic factors. Depletion of soil water resources need to develop efficient irrigation techniques for quality apple production. A new deficit irrigation strategy (PRD) has been developed that based on partial water supply of root-zone. This does not result a decrease in the sizes and yield of the fruit. The larger fruit size and lower firmness in frequently irrigated trees can result in excessive internal growth stresses that cause higher rate of fruit splitting. Many studies revealed the relationship between irrigation and yield quantity. Recent researches investigate the effects of irrigation on apple fruit quality particularly on the colouration and post-harvest quality. Use of cooling irrigation improves the development of coluour an apple fruit but its schedule can influence on the incomes. Aroma volatiles are responsible for odour and contribute to overall flavour of the fruit and its processed products. Deficit irrigation had only affects some volatile aroma but no the all of concentrations in apple fruit. In the future the high apple quality for consumers could be provided with improvement of transpiration-yield model based on the water requirement of varieties and economic irrigation schedules.

  • Effect of the placement of self-incompatible apricot varieties on their yield in commercial plantations
    82-86.
    Views:
    1213

    Earlier studies concerning self-, free- and cross- fertilization of apricot varieties grown in Hungary, proved the existence of self-sterile as well as self-fertile varieties within the recommended assortment. The self-sterile and partially self-fertile varieties should be planted in association with polliniser varieties, only. The present paper reports about the yields of trees of the widely grown, self-sterile local variety, Ceglédi óriás (Giant of Cegléd), depending on the distance of adequate polliniser trees. In the univarietal, 27 row-wide block of the relevant variety, an efficient polliniser, Magyar kajszi was planted to the 10th and 19th row. In the close vicinity, another block of polliniser, Rózsakajszi C. 320 was located. The number of fruits set per tree has been counted or estimated in two consecutive years. In both seasons, the yield of the Ceglédi óriás trees diminished with the growing distance from the nearest polliniser trees. Those trees in the center of the block, between the two (10th and 19th) rows of Magyar kajszi bore acceptable yield (40 kg/tree in 1987), however, considerable reduction of the number of the fruits set was stated already in the 4-5th row from the polliniser away. Similar gradient of fruit set was apparent in relation to the neighbouring block of Rózsakajszi C 320. The beneficial effect of the vicinity of polliniser varieties was obvious as far as the distance of the 10th row. Taking into consideration the self-sterility, the early blooming time and the poor fertilization of the variety Ceglédi óriás, a planting design of associating it with at least two polliniser varieties (e.g. Gönci magyar kajszi and Ceglédi bíbor) is highly recommended. On the basis also of earlier results, a proposal has been developed for the association of apricot varieties as recommendations for optimising yields. Blooming time, fertilizing potential, schedule of the picking season and market possibilities have to be considered simultaneously.

  • Effects of farmyard manure (FYM) and blended NPSB fertilizer rate on growth and yield of potato (Solanum tuberosum L.) in Gewata, Kaffa, southwest Ethiopia
    14-22.
    Views:
    333

    Potato (Solanum tuberosum L.) is an essential crop for nutrition and food security and generating income to small-holder farmers in Ethiopia. Productivity of the crop is, however, limited by poor nutrient management practices and low soil fertility. In most parts of potato growing areas of Ethiopia, soil are deficient in macro (nitrogen, phosphorus and sulfur) and micro nutrients (boron) which are known to affect production and productivity of potato. A field trail was accompanied to determine the growing response of potatoes ’Belete varieties’ to combine the treatment of farmyard manure and blended NPSB (nitrogen, phosphorous, sulfur and boron) fertilizer at Gewata, southwest Ethiopia during 2019/2020 main cropping season. The variables are laid out four level of farmyard manure (0, 5, 10 and 15 t/ha) and four level of blended NPSB fertilizer (0, 50, 100, and 150 kg/ha). The treatments were organized in a completely randomized block design with three replications using a 4x4 factorial layout. SAS (version 9.4) was used for data were analyzed. The finding indicate that, combined application of FYM (farmyard manure) with NPSB significantly (p<0.01) affects plant height, average mass of tuber, number of marketable and unmarketable tuber per hill, and tuber yields per plot. It also significantly (p<0.05) influenced days to flowering, maturity, and tuber number per hill. The highest tuber weight (99.33 g), tuber number per hill (9.67), and yield (34.10 kg) per plot were recorded from the mixed fertilization of 15 t FYM with 150 kg/ha NPSB mineral nutrients. As a current finding, it can be stated that the combined use of FYM (15 t/ha) and NPSB blended fertilizer could improve potato growth and yield in the study area (150 kg/ha).

  • Yield and composition of supercritical fluid extracts of different Lamiaceae herbs: Satureja hortensis L., Ocimum basilicum L. and Melissa officinalis L.
    75-79.
    Views:
    363

    In our work the effectiveness of supercritical carbon dioxide extraction was studied on volatile and nonvolatile components of Lamiaceae herbs. The aim of our investigations was to determine the optimal extraction parameters yielding high amount of volatiles and nonvolatiles in a desirable composition. As plant materials, dried and powdered cude drugs of Satureja hortensis, Ocimum basilicum and Melissa officinalis were chosen. Pressure (8-50 MPa), temperature (35-60 °C), time (5-60 min) and the ratio of modifier (5-50% methanol) of extraction were regulated. Results obtained by supercritical fluid extraction (SFE) were compared to that of the conventional extraction procedure, hydrodistillation (HD). In the case of Satureja hortensis, Ocimum basilicum and Melissa officinalis extract yield of SFE was comparable to the essential oil amount obtained by hydrodistillation from the same drug. Essential oil rich extracts were analysed by GC-FID, while extracts rich in nonvolatile compounds were analysed by HPLC. We have found that yield and quality of SFE extracts highly depend on the conditions of extraction.

  • A preliminary study on some features of two new resistant apple cultivars in a multi-row planting system
    11-14.
    Views:
    910

    The aim of this work was to report preliminary results on some features of two new resistant apple cultivars (cvs. ‘Galiwa’ and ‘Story Inored’) in multi-row system in the early bearing years of the orchard. Trees were planted in spring of 2015 in double row design (3.5 m+1.4 m x 1.0 m) with planting density of 5357 tree/ha. According to our results cv. ‘Story Inored’ presented more vigorous growth, than cv. ‘Galiwa’. Trees of cv. ‘Story Inored’ reached 2.7 m in the third year, but cv. ‘Galiwa’ could reach only 1.95 meter. Due to late spring frost 100% yield loss was observed in the second year. In 2017 cv. ‘Galiwa’ produced 5.3 kg/tree (25 fruit/tree), while cv. ‘Story Inored’ presented 7.7 kg/tree (50 fruit/tree). Average yield was 28.4 t/ha for cv. ‘Galiwa’, as ‘Story Inored’ reached 41.3 t/ha in the third year. Cultivar ‘Galiwa’ reached the required fruit size (79.1 mm), but its coloration was weaker (43% fruit surface color). Cultivar ‘Story Inored’ can be described with smaller fruit size (69 mm) and higher percentage of surface color (93%).

  • Nutrient demand of stone fruits
    19-23.
    Views:
    258

    Effects of nitrogen, phosphorus and potassium fertilization were investigated on the change of nutrient content, vegetative and generative production of apricot, peach and sour cherry trees, as well as on frost hardiness in long term experiments. Nitrogen and phosphorus fertilization increased only the concentration of these elements in cherry leaves without effect on growth and yield. Consequent potassium effect was proved on these stone fruit species. Effect on yield appeared following the first higher crop load.

    Potassium supply has positive effect on frost hardiness of apricot and sour cherry flowers and peach flower buds.

    In peach, the lime content of soil decreased the yield but it could be compensated by potassium dressing to some extent. Favourable nutrient boundary values were determined for soil and foliage.

  • Economic analysis of up-to-date sour cherry or in Hungary
    89-94.
    Views:
    373

    In this study cost-profit analysis is carried out to up-to-date Hungarian sour cherry orchards. These orchards cover only 1 to 3 thousand hectares from the sour cherry territory of 16 thousand hectares. In a many-year-average a yield of 15 tons per hectare may be reached in up-to-date sour cherry orchards cultivated under high standard conditions. Per hectare direct production costs take up of approximately 1000 thousand HUF, from which the major portion (60%) is accounted for the personal cost of harvesting. Regarding the above mentioned average yield and a selling price of 100 HUF per kilogram a revenue of 1 500 thousand HUF may be realized, which results in a per hectare contribution of 500 thousand HUF. To sum up, regarding the present extremely unfavourable selling price only reaching an average yield of 15 to 20 tons per hectare may lead to appropriate profit.

  • Comparison of three soil cultivation method in case of grape
    47-50.
    Views:
    335

    Our results show that the different cultivation methods have effect on the yield and the grape quality as well. In 2008 and 2009 the straw mulch proved to be the best solution regarding the yield. The soil compaction was reduced in these plots and the photosintetical activity was also higher. Straw mulch could conserve the moisture content of the soil. The less yield was observed in case of barely covered vines and also the vegetative growth of the grape was less intensive in case of these vines, but it seems to be contributed to the conformation of suitable microclimate for Botrytis infection.

  • The effect of the limitation of insect pollination period on the fruit set and yield of temperate-zone fruit tree species
    90-95.
    Views:
    3413

    The duration of effective bee pollination period was limited by caging flowering branches for shorter or longer time in blooming fruit trees in a number of experiments during the past decades. In the case of self-sterile fruit species and cultivars (apples, pears, quinces, some plums, some sour cherries) even partial limitation of the effective duration of bee pollination period significantly reduced the fruit set and the yield. In the case of self-fertile apricots the effect of the total and also the influence of partial limitation of bee pollination period was the same as in the case of the mentioned self-sterile fruits. On the other hand, in the case of another self-fertile fruits (some plums, some sour cherries), the effect of partial limitation of bee pollination period was usually small, but complete (or incomplete but strong) limitation of be pollination usually resulted in a strong reduction of yield. This means that not only self-sterile but also self-fertile fruits clearly depend on insect (bee) pollination. This is because pollen dehiscence of anthers and the receptive period of stigmas do not overlap in time within the individual flowers. Stigmas in self-fertile trees, therefore, need pollen carried by bees from another flowers of the same tree (or compatible pollen from another trees). Accordingly, additional bee pollination (moving bee colonies to the orchards in flower) is needed to all kinds of temperate-zone fruit tree species when bee visitation of plantations is not abundant enough for some reasons.

  • Foliar Nutrition and Post-Harvest of Onion Seed: Effects of storage temperatures, storage period and foliar nutrition
    29-47.
    Views:
    495

    The aim of onion bulb storage is to meet consumer demand for extended availability of onions whilst maintaining product quality. The principal biological factors leading to onion bulb deterioration are respiration, resumption of growth and pathogen attack. In onion bulbs a dormant period, when sprouting and rooting cannot be induced, is followed by a period of internal changes that prepare the bulb for breaking of dormancy and subsequent growth. Out of storage, the bulb then proceeds towards flowering and seed production. Two successive winter seasons of 2008/2009 and 2009/2010 were conducted under sandy soil conditions to study the effect of spraying with 12 commercial compounds on yield and yield components of onion seeds and storage The seed yield of each commercial compounds plot from previous experiment was divided into two groups, storage under room temperature and 5°C. Seeds transferred immediately after drying to Increasing Export Competition of Some Vegetable Crops Project Laboratory located in Faculty of Agriculture, Cairo University. The effects of storage temperature, storage period and foliar with some commercial compounds on onion seed quality were considered. Storage in 5°C had the higher germination percentage than storage in room temperature. Results indicated that as storage period increased the germination percent decreased. The treatment with boron or amica in the first season had the highest germination percentage. While, the treatment with union Zn, union feer, union Mn, boron, elga 600, caboron, amica, hummer or amino X had the highest germination percentage in the second season. Storage in 5°C resulted in higher moisture content than storage in room temperature. Regarding the effect of storage period on moisture content, the water content was significantly increased with prolongation of storage period. The lowest values of water content were recorded for treatments with union feer, shams K or boron in the first season, and union feer, shams K, boron, magnesium, shetocare or hummer in the second one. Catalase activity was significantly decreased as storage period increased. The treatment with shams K, boron, shetocare or amino X had the highest catalase activity in both seasons. Peroxidase activity was significantly decreased as storage period increased. Foliar application with boron had the highest peroxidase activity in both seasons. Seed stored in room temperature had the higher malondialdehyde content than those stored in 5°C in the second season. The malondialdehyde content increased as storage period increased. The treatment with magnesium, caboron and the control in the first season, and the treatment with magnesium and the control in the second season had the highest malondialdehyde content.

  • Influence of foliar nutrition on apple production
    15-18.
    Views:
    253

    On the basis of different experiments the technology of intensive foliar nutrition was studied in apple orchards in the period from 1996 until 2000. Yearly apple nutrition programs based on soil analyses. The foliar nutrition program was prepared in accordance with the soil, fruit analyses and climatic conditions. If needed, certain improvements were made according to the analyses of leaves and precipitation in the current year. The richness of the soil and ratios between individual nutrients gradually improved. The foliar nutrition influenced the yield quantity, quality and flower bud differentiation. The yield was doubled and the mean of five years reached 70 tons per hectare. In spite of high yields there were no problems with alternative bearing. The analyses of soluble solids, firmness, fructose, glucose, sucrose, malic acid, citric acid in the fruits and mineral soil composition indicated that the produced fruits were of high quality despite greater yields.

  • Yield and composition of supercritical fluid extracts of different Lamiaceae herbs
    79-82.
    Views:
    367

    In our work the effectiveness of supercritical carbon dioxide extraction was studied on volatile components of Lamiaceae herbs. The aim of our investigations was to determine the optimal extraction parameters yielding high amount of volatiles in a desirable composition. As plant materials, dried and powdered cude drugs of Thymus vulgaris, Thymus pannonicus, Satureja hortensis, Ocimum basilicum, Rosmarinus officnalis and Salvia officinalis were chosen. Pressure (8-30 MPa), temperature (35-60 °C) and time (5-60 min) of extraction were regulated. Results obtained by supercritical fluid extraction (SFE) were compared to that of the conventional extraction procedur, hydrodistillation (HD). In the case of Thymus vulgaris, Thymus pannonicus and Salvia officnalis, extract yield of SFE was comparable to the essential oil amount obtained by hydrodistillation from the same drug. Essential oil rich thyme extracts were analysed by GC-FID. We have found that yield and quality of SFE extracts highly depend on the conditions of extraction.

  • Overwintering capability and spring population size of honeybee colonies (Apis mellifera L.) in Hungary
    153-156.
    Views:
    209

    Honeybee races and ecotypes of different genetic background have different population development in spring. Some of them can reach the necessary population size by the beginning of Robinia pseudoacacia (black locust) blooming period. There were significant differences in the spring population development between the colonies of different genetic background. The Italian races (A. m. ligustica) and their cross-breeds over-wintered poorly in Hungary, their spring population was low and they collected small amount of Robinia honey. The Austrian improved Carniolan (A. m. carnica) colonies over-wintered well, they had the largest spring population in both years. There was no significant difference between the size of the spring population of the same colonies of different genetic background in 1995 and 1996. The rate of the population development of the colonies was different in the two examined years. There was strong correlation (r = 0.8) between the spring population size and the Robinia honey yield, and between the mid-April population size and the Robinia honey yield of the colony groups of different genetic background. Spring population size also important in the effective pollination of fruit tree species that bloom earlier than the black locust trees.

     

  • Character association and genetic gain of nine agronomic traits of F1 populations in onion (Allium cepa L.)
    50-58.
    Views:
    694

    F1 populations of half diallel cross were considered for this investigation. Phenotypic component of variation (s2P) was higher than genotypic (s2G), interaction ((s2I) and within error (s2w) components of variation. Trait bulb weight showed the highest values for s2P, s2G, s2I and s2w. The noticeable amount of phenotypic, genotypic, interaction and within error covariation was found in the combination of BW×BY, possibly indicating wide scope of selection for this pair of characters. Genotypic correlations were higher than the respective phenotypic correlations. This situation was also marked in the path coefficient analysis. Bulb yield/plot showed highly significant and positive correlation coefficient with other characters both at phenotypic and genotypic levels. When all the nine characters were included in an index, it exhibited the highest genetic gain as percentage. When a combination of two or more characters was studied in a function, the efficacy was higher than that of direct selection for bulb yield. The combination of five, six, seven or eight characters showed higher percentage of expected gain. Due to significantly correlated with BY and having high positive direct effect at phenotypic level characters viz., LL, BW, PH and NLs is considered as primary yield components. Again combinations of these four characters gave the commendable expected genetic gain of 330.7290% may be considered as important selection index for this material.

  • The effect of spring frosts on the nectar production and the bee visitation of fruit trees
    86-89.
    Views:
    929

    Fruit tree species suffered very strong spring frosts in 1997 in Hungary. This caused partial or total damages at buds and flowers depending on site and time of blooming. It was demonstrated at a number of experiments that frost and cold weather also strongly affected the nectar production of surviving flowers. No or very little amount of nectar was measured in flowers first of all of early blooming fruit tree species (apricot) but also of pear and apple in some places. In spite of this fact intensive honeybee visitation was detected in the flowers of fruit trees that suffered partial frost damage only at those sites where honeybee colonies were placed in or at the experimental plantations and the lack of sufficient amount of nectar did not affected bee behaviour seriously on fruit flowers. This means that bad nectar production failed to affect bee visitation of fruit trees definitely. The reason for this was the fact that not only fruit trees but another early bee plants (wild plants, too) suffered frost damage. Accordingly, in lack of forage bees intensively searched for food at blooming fruit trees with some living flowers. Consequently, there was an acceptable yield at those plantations where bud and flower damage was not complete. Accordingly, intensive bee visitation (that is moving additional bee colonies to overpopulate fruit orchards with honeybees) can be an effective tool to decrease or eliminate the detrimental effect of spring frost on the yield of fruit trees where bud or fruit damage is not too high.

     

  • Efficacy of N-phenylphtalamic acid in some Solanaceae species
    89-91.
    Views:
    218

    : N-phenylphthalamic acid — Cl4H1 1 NO3 (Nevirol 60 WP) was successfully used for enhancing yield in some important vegetable crops namely, tomato (Lycopersicon esculentum), chilli (Capsicum annuum) and brinjal (Solanum melongena) of Solanaceae. Aqueous sprays with 0.2% and 3.0% significantly enhanced fruit production in chilli and tomato respectively. On the other hand, various treatments in brinjal failed to enhance yield significantly. The increase in yield in both tomato and chilli is largely due to increase in the number of flowers and fruit-set percentage.

  • Flower characters and self-fertilization capacity in relation to the bee pollination at sour cherry cultivars
    121-132.
    Views:
    836

    Detailed studies and comparisons were carried out on those flower characters of sour cherry cultivars that may affect bee pollination of flowers. Flower characters of sour cherry are fairly similar to other temperate zone fruit tree species. Their relatively small flowers distinguish the Cigánymeggy-types of cultivars from the flowers of tart cherries cultivars that are conspicuously larger, almost as large as the sweet cherry flowers. The relative position of flower organs was much more variable according to the season than according to the cultivars. So the differences were rather the consequences of seasonal effects than of variety features of sour cherry cultivars. As far as individual cultivars are concerned differences in the nectar production and the sugar concentration are revealed rather between groups of cultivars than between individual cultivars. The pollen production of flowers was extremely changeable in consecutive years. Most honeybees collected nectar at sour cherry flowers; pure pollen gatherers and mixed behaviour bees were half as frequent but differences among the behaviour of honeybees according to cultivars cannot be stated. The fidelity of honeybees to sour cherry is less expressed than to some other fruit tree species. Accordingly, it is very strongly suggested to take the competitive effect other plant species (weeds) flowering in and around the orchard carefully into account when organizing additional bee pollination in sour cherry plantations. Several sour cherry cultivars possess more or less self-fertilization capacity but this is greatly changeable according to the season. It has been proved that self-sterile sour cherry cultivars are sensitive even on the partial restriction of the effective time of bee pollination and it is to be stressed too that even in the case of partly self-fruitful cultivars bee pollination is also vital in yield formation because medium or strong restriction of the effective bee pollination period is of a definite negative effect on their fruit set and yield. In years with unfavourable weather the yield can dramatically be reduced sometimes down to nil. However, very high fruit set is also unfavourable because a negative correlation was detected between the final set and the mean mass of fruits.

  • Analyses of temporal dynamics of brown rot development on fruit in organic apple production
    97-100.
    Views:
    431

    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.

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