Search
Search Results
-
What mechanisms are involved in cabbage-clover intercropping and a further proof of the 'host plant quality' hypothesis
47-51.Views:133Over 10 years of field trials show reductions of most of the pests in Brassicas undersown by clover. The pest-reducing effects are due to the 'appropriate / inappropriate landings' hypothesis (Finch, 1996), and the 'host plant quality' hypothesis (Theunissen, 1994). To find out the mechanisms within the 'host plant quality' hypothesis in the most promising intercropping (collards undersown by clover) glasshouse experiments were conducted to see whether intercropping influences the mean relative growth rate, fecundity and time of maturity of Myzus persicae (Sulzer) (Homoptera: Aphididae) a common pest of Brassicas.
The treatment modelling intercropping showed the smallest mean relative growth rate, delayed the maturity and slowed down the growth of cabbages. The treatment modelling monocropping showed the highest mean relative growth rate and the maturity was reached earlier. These results may indicate that intercropping delays the growth of settled aphid populations, giving another proof that in the case of clover undersown cabbages the 'host plant quality' hypothesis is likely to be acting. The differences between treatments where the roots of clover and cabbages were separated and allowed to grow together suggest that the effect is via the roots by competition.
-
Cultivars, marketing and integrated Production of apples in the Czech Republic
87-92.Views:122Development in apple production in the Czech Republic has been adversely effected during a few recent years by escape of capital investment from the agrifood industry (due to privatisation, restitution and transformation). On the other way round the competition on the domestic market is much higher than it was before because of unlimited import of subtropical and tropical fruit and some import of traditional fruit species as well. Therefore fruit growers are very much concerned in any possible means (which are not economically feasible) to be more competitive. One of the most common approach is the use of new cultivars bred in the country which are resistant or tolerant to diseases and offer better quality both for fresh market and processing. Another way for increasing competition ability for fruit growers is the join and mastering of integrated production which also considerably improve the quality of fruit as far as aspects of health are meant.
-
Changes in Some Quality Criteria During Controlled Atmosphere (CA) Storage of Peaches
58-61.Views:123Intensive research has been implemented on different aspects of the bee pollination of pear in Hungary in the past decade, extending to the following topics: the effect of the opening sequence of the flowers within the inflorescence of pear cultivars on the effectiveness of bee pollination; the nectar production of flowers of pear cultivars; intensity of honeybee visitation and their foraging behaviour at the flowers of pear cultivars; flower constancy of honeybees to pear plantations; competition by weeds in bloom for bee pollination in flowering pear orchards; and some aspects to the bee pollination strategies of pear plantations (the effect of the limitation of bee pollination period on the set and the yield, possible compensation of frost damage of flowers by bee pollination in pear orchards, the optimal size of single cultivar block in pear plantations). The results of these studies are reviewed in this paper and some important aspects that need further studies are outlined.
-
Some flower characters, variety features and environmental effects affecting bee pollination of pear (Pyrus communis L.): a review of the results of latest research
59-66.Views:177Intensive research has been implemented on different aspects of the bee pollination of pear in Hungary in the past decade, extending to the following topics: the effect of the opening sequence of the flowers within the inflorescence of pear cultivars on the effectiveness of bee pollination; the nectar production of flowers of pear cultivars; intensity of honeybee visitation and their foraging behaviour at the flowers of pear cultivars; flower constancy of honeybees to pear plantations; competition by weeds in bloom for bee pollination in flowering pear orchards; and some aspects to the bee pollination strategies of pear plantations (the effect of the limitation of bee pollination period on the set and the yield, possible compensation of frost damage of flowers by bee pollination in pear orchards, the optimal size of single cultivar block in pear plantations). The results of these studies are reviewed in this paper and some important aspects that need further studies are outlined.
-
Foliar Nutrition and Post-Harvest of Onion Seed: Effects of storage temperatures, storage period and foliar nutrition
29-47.Views:223The 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.
-
Nutritional aspects of producing fruits organically
69-74.Views:345Recent interest to avoid use of agrochemicals in fruit growing to safeguard environmental and human health has stimulated interest in organic fruit production (OFP) all over the world. Organic production requires a holistic approach to agricultural ecosystem management. Because of the perennial nature of orchards, this is not a great departure from conventional orchard management, except that corrective techniques are limited primarily to naturally derived materials. Organic mineral nutrition management hinges on two principles: 1) practices that lead to the build up and maintenance of soil that is biologically active and high in organic matter; 2) supplementing the mineral nutrients provided by the soil with fertilizers from approved sources. Organic orchards should be sited on land with superior soils and preplant soil preparation to increase organic matter and correct any sub-optimal soil characteristics. For successful organic fruit growing the following statement should be considered:Weed management is critical to reduce competition for nutrients and water. Soil and leaf analysis provide the basis for correcting mineral nutrient deficiencies or imbalances in organic production. It may be necessary to use a number of strategies to supply mineral nutrients over the life of the orchard. The slower, natural methods applied require a management approach that is simultaneously patient and dynamic.
-
Fruit drop: The role of inner agents and environmental factors in the drop of flowers and fruits
13-23.Views:525The basic conditions of fruit set (synchronic bloom, transfer of pollen, etc.) still do decide definitely the fate of the flower (Cano-Medrano & Darnell, 1998) in spite of the best weather conditions (Stösser, 2002). Beyond a set quantity of fruits, the tree is unable to bring up larger load. A system of autoregulation works in the background and causes the drop of a fraction of fruits in spite of the accomplished fertilisation and the equality of physiological precedents (Soltész, 1997). There are also basically genetic agents in action. The further development of fruits maintained on the tree depends mainly on the growing conditions (e.g. water, supply of nutrients, weather adversities, pruning, fruit thinning, biotic damages, etc.), which may cause on their own turn fruit drop especially at the time of approaching maturity.
-
Economic aspects of aged apple plantations in Hungary
13-16.Views:147Being competitive is a goal all over in the EU. Competition is free and getting closer among the competitors of the apple industry. In Hungary, one of the most important issues of apple industry has been what are the prospects for aged plantations, which account for 50% of crop land. Based on our results, 80% of those apple plantations on the down-grade yielding apple, the ones only for processing, do not meet the criteria of competitive production. For those plantations in better shape that yield 30-40 t/ha, of which at least 20-30% are for fresh production, it can he profitable. Because of the future trend in technology and economy, however, even the latter ones can not be considered being competitive in the long run.