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A review of the bee pollination research on temperate zone crop plants in the past decade: results and the need of further studies
7-23.Views:152Intense research was made on the pollination of cultivated crop plants in the temperate zone region during the past decade. Some 400 publications appeared on the subject and some additional 150 papers on the effect of pesticides to the most important pollinating insects, the honeybee and the wild bees. Progress of knowledge is discussed in this paper based on the most important publications. Most new results relate to field crops and deciduous fruit species and much less to field vegetables and small fruits. Great effort was taken to improve insect pollination of crops grown under cover. All these are connected to the utilization of the honeybee as a pollinating agent and much less to native or managed wild bees. However, a number of questions arose partly from the results of latest pollination research and partly from practical experiences in commercial plant production. These indicate several research tasks to understand and to solve the problems possibly in the near future. The questions concentrate on the effectiveness of bee visits in the pollination of individual crop plants and their different cultivars and on the reliable estimate of the overall amount of bees as well as on the control of bee density during the flowering periods of crops for optimal, controlled pollination in the changing environment of agricultural crop production.
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Evaluation of biological control option for Bagrada bug (Bagrada hilaris (Burmeister)) in Kenya
43-47.Views:82Brassica production is important for economic development of Kenya. Bagrada bug, a significant pest of brassicas, affects their yields and quality, currently posing a threat to both local and commercial vegetable production in Kenya. Biological control of bagrada bug using natural enemies is a cheaper and environmentally friendly method. The study aimed to identify native egg parasitoid species in Kenya. A field prospection survey of the bagrada bug egg parasitoid was done by a series of bagrada bug egg exposure in different parts of the country. Freshly laid bagrada bug eggs in cards were exposed for possible parasitism in the field for three days. The eggs were later carried to the laboratory at NSRC to await hatching. Two egg parasitoid species Trissolcus basalis (Hymenoptera, Scelionidae) and Gryon sp. were identified during the study after a period of bagrada bug egg exposure in Machakos and Kisumu. Two cards with parasitized bagrada bug eggs were recovered from Machakos from which one card yielded four parasitoids of one species Trissolcus basalis and the other yielded two parasitoids Trissolcus basalis and Gryon sp. One card with two parasitized eggs by Trissolcus basalis was recovered from Kisumu, however, there were no parasitoids identified in Nanyuki, Naivasha and Kitengela where bagrada bug is also prevalent. Results showed parasitoid presence in fields with high bug populations compared to areas with few or no Bagrada bug infestations. Conducting trials in both laboratory and field settings is recommended to obtain clear data on the effectiveness of the identified egg parasitoid in managing the bagrada bug population.
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Allyl isothiocyanate baited traps to monitor cabbage flea beetles (Phyllotretra spp., Coleoptera: Chrysomelidae)
95-99.Views:189A new trapping concept has been proposed based on a volatile compound, allyl isothyocianate, known to be attractant to some of these insects for a long time.
(l) The first question was whether this compound is effectively attractive to all flea beetle species attacking cabbage under our conditions? Field experiments were made at different localities with non-sticky baited traps early and late spring. Eleven Phyllotreta species attacking cabbages were captured at baited traps most of them were first observed at this bait. So the bait has proved to be sufficient for use for trapping purposes effectively.
- Based on these findings a second question arose whether the captured samples reflected the specific composition of natural flea beetle populations at trapping localities? To reply the question field samples were taken at four different kinds of cabbage crops and at a fallow ground in the close vicinity by a manual sampler device suitable to detect the local composition of flea beetles and trapping was made parallel with baited and unbaited traps from early spring to early autumn. No significant differences were found between the specific structures of Phyllotreta assemblages sampled with the different methods applied. This means baited traps reflected the specific composition of local Phyllotreta populations fairly well.
- Thirdly, the most effective trap design was searched for. Some sticky and non-sticky trap designs which had been developed to capture other insects were compared. The tested sticky and funnel trap designs baited with allyl isothiocyanate captured large numbers of flea beetles attacking cabbages. Results showed that non-sticky funnel traps were more effective than sticky delta traps. Accordingly, non-sticky funnel trap designs can advantageously be used and could possibly be recommended in plant protection practice to monitor flea beetles attacking cabbages as their catching capacity is considerably greater than that of the delta type and additionally captured beetles are much cleaner, more intact and consequently their identification is much easier.
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The brown rot fungi of fruit crops (Monilinia spp.): II. Important features of their epidemiology (Review paper)
17-33.Views:246Plant disease epidemiology provides the key to both a better understanding of the nature of a disease and the most effective approach to disease control. Brown rot fungi (Monilinia spp.) cause mainly fruit rot, blossom blight and stem canker which results in considerable yield losses both in the field and in the storage place. In order to provide a better disease control strategy, all aspects of brown rot fungi epidemiology are discribed and discussed in the second part of this review. The general disease cycle of Monilinia fructigena„M. laxa, M. fructicola and Monilia polystroma is described. After such environmental and biological factors are presented which influence the development of hyphae, mycelium, conidia, stroma and apothecial formation. Factors affecting the ability of brown rot fungi to survive are also demonstrated. Then spatio-temporal dynamics of brown rot fungi are discussed. In the last two parts, the epidemiology of brown rot fungi was related to disease warning models and some aspects of disease management.
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Preliminary data on attractiveness of phenylacetaldehyde-based lures on economically important plant bug pests (Hemiptera: Miridae)
87-94Views:354Several plant bug species (Miridae) are important pests of crops and vegetables, thus monitoring them is of essential importance for effective pest control. During the current, preliminary study synthetic plant volatile combinations were tested in field conditions in Hungary in alfalfa fields. Beside semiochemical baited traps, sweep-netting was also performed. In the experiments three plant bug species were found in higher numbers: Adelphocoris lineolatus, Lygus rugulipennis and L. pratensis. As a novel, interesting finding L. pratensis was attracted to phenylacetaldehyde baited traps. For all species, both males and females were trapped in all combinations. Sweep-netting and semiochemical baited traps showed different efficacy in case of the three species, as sweep-netting catches were highly biased for A. lineolatus, which indicates the higher efficacy of this method as compared to the tested semiochemical-baited traps. On the other hand, semiochemical baited showed better performance for L. rugulipennis and L. pratensis. For these species none of the tested combinations performed better than phenylacetaldehyde baited traps. The potential implication of results in view of monitoring are discussed.
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Irrigation modeling in a pear orchard
75-79.Views:289The pear has large water requirement, therefore the planting of high density and grass covered pear orchards are needed irrigation
conditions in Hungary. Drip irrigation spread in the orchards is due to the 90–95% of water use efficiency. One of the key role of irrigation is the
proper determination of evapotranspiration and crop coefficients. As there is a considerable lack of information for different crops or fruits the
Penman-Monteith method is used for the estimation of evapotranspiration, using CROPWAT 8.0. The research field was the genetic collection of
pear at Újfehértó, in Hungary, which is situated in Nyírség meso-region. Our aim was to establish drip irrigation at this site. Based on the results
of CROPWAT irrigation model the mean amount of the total gross irrigation is between 230–270 mm, within 3 irrigation interval regarding
climatic and rainfall data of the last 10 years. In 2009, due to heavy drought, the total gross irrigation was 355,4mm/year on sandy soil calculating
with 45% total available water depletion in 5 irrigation interval. The sizing of the irrigation system was set to the maximum 0.55 l/s/ha, which is
6.3 l/tree/h. 6.3 l/tree/h can be carried out with a drip emitter having 16 mm wing lines diameter, 4 l/h water flow at 3 atm pressure. -
Influence of abiotic factors on the green mass and seed productivity of the raw material of Levisticum оfficinalе c. Koch in the conditions of Transcarpathia
46-51.Views:281For the wide implementation of Levisticum officinalе C. Koch in Transcarpathia into production it is necessary to widen its sort composition, as it is rather poor in Ukraine. Solving this problem is possible by enriching the source material with the samples of different ecological and/or geographical origin, by studying the influence of abiotic factors on the formation of green mass and seed productivity, separating the specimens best adapted to the conditions of growing, involving them into the selection process and creating new, highly productive sorts on this basis. The scientists of the Transcarpathian State Agricultural Experimental Station (TSAES) conducted researches (during 2011-2016) on the adaptive potential of the source material of the type of Levisticum officinalе C. Koch, which counts seven samples (Ukraine – 5 samples, Poland – 1, and Romania – 1), the selection work on creating new varieties for the given region is being done. The investigations were made on soddy podzolic gleyed low-humus soils with low content of nutrients. The results were obtained on the basis of generally accepted methods of investigation, i.e.: laboratory, field, visual, measuring-weighing, biochemical, mathematically statistic, and comparative-calculating. In the conditions of Transcarpathia the spicy greens of the high quality L. officinalе C. Koch are being gathered on days 25-30, the output of the essential oil makes up from 0.72 tо 1.89% on c.d.s., depending on the climate conditions of growing. The plants pass through all the stages of development, the bush is 55.4 to 92.7 сm in height, the plants form a big amount of rosette-shaped stems (11-34 pieces), the productivity of spicy greens is between 9.9 and 42.1 t hа1. The scientists of TSAES created the following sorts – Mriya (А. с. 06131 Ukraine, first registered in the State register of plant varieties of Ukraine) and Coral (Pat. on the variety № 140830). Economic effect from growing of the Coral variety in the conditions of Transcarpathia is 10230 UAH/ha and the level of profitability is 28.4%. The geographic position and agroclimatic conditions of Transcarpathia, as well as the unpretentiousness of L. officinalе C. Koch. tо the conditions of growing contribute to the enrichment of the local flora with useful plants; and the rich chemical composition contributes to the spread of this culture in the given region.