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NEGFRY system for late blight control on potato in Lithuania
2002
Danyte, V. (Lithuanian Inst. of Agriculture, Akademija, Kedainio reg. (Lithuania))
Late blight (Phytophthora infestans) is one of the most serious potato diseases. The light blight forecasting is a very important factor for the protection of potato plants. NEGFRY is a decision support system for scheduling the chemical control of potato late blight. Trials were carried out in 2000-2001 at the Lithuanian Institute of Agriculture (LIA) in Dotnuva in medium early and moderately susceptible to late blight varieties. Ordinary plant protection systems against late blight and different NEGFRY models were compared. Results of two years' investigations show that by using NEGFRY models we can obtain satisfactory protection of potato crop and get higher yield using fewer spray applications.
Показать больше [+] Меньше [-]Evaluation of microflora and somatic cell count changes in mastitic udder secretion
2002
Konosonoka, I.H. (Latvia Univ. of Agriculture, Sigulda (Latvia). Research Centre "Sigra")
Udder secretion samples from mastitic and healthy udders were examined at the Department of Veterinary Medicine of the LUA Research Centre "Sigra". In total, 117 samples from 117 cows were investigated. Somatic cell count was recorded for cows with clinical and subclinical infections, and uninfected cows. The mean somatic cell counts for cows with clinical and subclinical mastitis were 1 825 250+-417 697 cells ml*[-1) and 967 866+-75 796 cells ml*[-1), respectively. For healthy cows the mean somatic cell count was 87 666+-15 384 cells ml*[-1). Gram-positive microorganisms from the genera Micrococcus, Staphylococcus, Streptococcus, and Corynebacterium, and gram-negative microorganisms from the genera Enterobacter, Klebsiella, Salmonella, Escheria and Pseudomonas were isolated from samples from mastitic quarters.
Показать больше [+] Меньше [-]Spatial variation of temperature in two different types of Estonian loose-housing cowsheds
2002
Poikalainen, V. | Veermaee, I. | Praks, J. (Estonian Agricultural Univ., Tartu (Estonia))
The productivity, health and welfare of cows are considerably influenced by the microclimate of the cowshed in which they live. The present paper deals with the spatial variation in temperature within uninsulated wooden cowshed and cowshed renovated from stanchions into cubicles. The type of the cowshed (uninsulated wooden cubicle cowshed and renovated cowshed made of concrete elements) influences spatial variation of indoor temperature. Greater spatial variation existed in renovated cowsheds, but these remained within the range of cows' temperature comfort zone.
Показать больше [+] Меньше [-]Agroecological evaluation of organic and conventional cropping systems
2002
Guzys, S. | Petrokiene, Z. (Lithuanian Agricultural Univ., Akademija, Kauno reg. (Lithuania). Inst. of Water Management)
During the period 1995-1998, in the western part of Lithuania, the organic and intensive (conventional) cropping systems were compared on small autonomous drainage plots in limed Bathihypogleyi-Albic Luvisols (LVa-gld-w) and Dystri-Endohypogleyic Cambisols (CMg-n-w-dy) as well as non-acid Endocalcari-Endohypogleyic Cambisols (CMa-n-w-can) soils. This paper presents the summarised results of field crop productivity and the factors determining drainage water runoff as well as the migration and balance of elements in the organic and intensive cropping systems.
Показать больше [+] Меньше [-]Influence of seed treatment on the diversity of pathogenic fungus of flaxseed and seedlings
2002
Gruzdeviene, E. (Lithuanian Inst. of Agriculture, Upyte, Panevezys reg. (Lithuania). Upyte Research Station) | Lugauskas, A. | Repeckiene, J.
Major diseases occurring on flax crops in Lithuania are caused by Fusarium spp., Colletotrichum lini Manns et Bolley, Polyspora lini Laff. et Peth., Septoria linicola (Speg.) Gar. They can spread through seed, especially when the seed material does not meet quality standards. Microscopic fungi of other species can be found on flaxseed as well. Chemical seed treatment is one of the ways to control disease agents. When treated seed is sown, the seed treaters affect the indigenous micro-biota of the soil. The trial was carried out at the Upyte Research Station of the Lithuanian Institute of Agriculture in 1999. The tested seed treaters are registered for cereals in Lithuania. Our experimental results suggest that chemical treatment of flaxseeds is an efficient method to control seed-borne diseases. The microscopic fungi on seeds and roots of seedlings were analysed at the Institute of Botany. The data on the effect of seed treaters on the diversity of pathogenic fungi of flaxseed and seedlings, and the impact of treatment on the seedling infection are discussed in this paper.
Показать больше [+] Меньше [-]Genetic particularities of the population of causal agent of barley powdery mildew Blumeria graminis f.sp. hordei in Latvia
2002
Kokina, I. (University of Daugavpils (Latvia)) | Araja, I. | Rasals, I.
Evaluation of virulences of Blumeria graminis f.sp. hordei was started in Latvia in 1981, first in the Baltic States. Until 1994 the observations were carried out only in the central part of Latvia - Salaspils. As the climatic factors and the used barley varieties in various parts of Latvia are different, in 1995 we started regular observations of the particularities of the genetic structure of the pathogen population also in Daugavpils. The aim of this investigation was to detect particularities of the genetic structure of the pathogen population in different parts of Latvia in 1996-2000.
Показать больше [+] Меньше [-]The researches on the management of stream and ground water pollution in drained soils of karst zone in Lithuania
2002
Morkunas, V. | Rudzianskaite, A. | Sukys, P. (Lithuanian Inst. of Water Management, Vilainiai, Kedainiai reg. (Lithuania))
Trying to find the best solution for the ecological problem of karst zone (i.e. protection of surface and ground water from agricultural activity) it is important to determine the migration extent of plant nutrients leached from the soil into the streams and ground water depending on the type of land use. The paper presents the results of the studies carried out in two vicinities of intensive karst zone in Birzai district. The obtained results show the influence of drainage water on the quality of stream water in drained areas. It has also been determined that drainage water quality is influenced by soil forming rocks as well as by the type of land use. In the failures of karst zone, as well as in arable land the quality of ground water is worse, especially when ground water is found near the ground surface.
Показать больше [+] Меньше [-]ESP learner characteristics
2002
Kool, E. (Estonian Agricultural Univ., Tartu (Estonia))
As the majority of well-known researchers (All right 1982, Jordan 1989, Morrow 1977 etc.) evaluate needs analysis as the starting point for any kind of teaching and learning ESP, and the new developments in educational psychology contributed to ESP (Chambers F., 1980 etc.) emphasize a learner-centreted approach, the first attempt for such kind of data collecting was made in the Faculty of Veterinary Science, Estonian Agricultural University (EAU).
Показать больше [+] Меньше [-]Natural and economic risk factors in Estonian agriculture
2002
Astover, A. | Roostalu, H. | Vingissaar, V. (Estonian Agricultural Univ., Tartu (Estonia))
Agriculture more than any other branch of production is influenced by various natural, anthropogenic and economic risk factors on which the profitability of production and preservation of the environment in rural areas depend. The prerequisite of prevention or alleviation of risks is their all-round knowledge and consideration. In order to understand the nature of risks, they will be dealt with in the present study on the example of the cultivation of the most common cereal in Estonia - barley. The difference in barley yields, resulting from the pedoclimatic coditions of Estonia, may be 2-4-fold in different regions and in different years. At the same time, differences in the profitability of barley cultivation, depending on economic factors and on the specificity of production, may be up to 6-fold.
Показать больше [+] Меньше [-]Weed infestation and control in spring barley
2002
Vanaga, I. (Latvia Univ. of Agriculture, Jelgava (Latvia))
Weed surveys showed that annual broad-leaved weeds were dominant in spring barley sowings in central Latvia. Field trials on broad-leaved weed control in spring barley showed that herbicides Granstar and Duplosan Super at 0,5 and 0,25 doses gave good weed control. There were statistically significant relationships between the abundance of broad-leaved weed and the yield of spring barley when barley yield and broad-leaved weed population were both high.
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