Mineralinio azoto kiekio dirvožemyje ir azoto trąšų įtaka miežiams

Santr. anglBibliogr.: p. 99 (4 pavad.

Extraction and mapping of soil factors using factor analysis and geostatistical analysis on intensively manured heterogenous soils

|a To investigate both natural variability and anthropogenic inputs, a small lake catchment that collects water from slurry-irrigated (similar to 300 m(3).ha(-1) annual application) natural meadows was explored. Analysis of the distribution of heavy metals suggests that concentrations of Ni, Zn, Pb, and Cu are closely associated with the geochemical signatures of soil parent material and, to a lesser extent, with soil organic matter. The data set of selected soil parameters was subjected to factor analysis (FA), which reduced the dataset into two major components (Factors 1 and 2) representing the different elemental sources. Geostatistical analysis showed interrelationships between heavy metal accumulations and soil genetic properties. Contour mapping of these variables identified the areas where anthropogenic processes are especially evident. Such visual information allowed spatial identification of the optimum number of 'tipping points' for soil monitoring

Climate change impact on agriculture in Lithuania : challenges, situation analysis and forecast

Article introduces the concept of extreme events in Lithuania and current extreme weather events in isolation, assesses international experience in solving similar problems. Lithuanian climatic conditions have been gradually changing over the past 20 years. Climatic symptoms vary in different regions of Lithuania, but changes are observed everywhere. Lithuanian agriculture must find ways to adapt to the constantly changing climate. Prevention of climate change provides new opportunities for agriculture: on the one hand, products derived from biomass can replace minerals, and, on the other hand, can lead to carbon capture in soil. Animal husbandry is more resistant to impacts of climate change than agriculture is. However, possibilities for local communities adapt to climate change and mitigate its impact are highly dependent on socio-economic and environmental conditions and available resources. There are changes in livestockproduction. These changes may include: diversification, intensification, and (or) pasture management, livestock and crop integration, land use and irrigation expansion, and duration of the production processes, ecosystems and protection of nature, improvement of routes for transportation of raw materials and produce, shortening of distances, mixed livestock farming systems.It is necessary to emphasize the importance of diversification ofbusiness ofsmall farms. The essential thing is adaptation to climate change, which means the need for rapid recovery and cost reduction actions. Climate change over the next two decades cannot be avoided, yet some degree of protection for our societies and economies from these changes can be achieved, for example, provision of relevant information, improved planning for production under particular climatic conditions better suited to crop growth and infrastructure development. It is very important to develop a common international vision of long-term goals and international co-operation, to achieve common goals to which each country will have to contribute its share, coordinate the actions of neighbouring countries in managing climate change

Energy potential of cereals crop in Middle Lithuania

Fossil fuels - oil, coal, and natural gas - dominate the world energy economy, covering more than 80% of the totai primary energy supply. Commitments to decreasing greenhouse gas emission, desire to secure and diversify the supply of energy and uncertainties related to oil price are rendering various biomass types more interesting fuels in industrialized countries, and the modern use of biomass is inereasing rapidly in many parts of the world. Lithuania has a goal to reach 23% of all energy will be make from renewable resources in 2020. In nowadays the bigger part of renewable energy are make from wood and wood wastes. To reach the goal of 2020 will be necessary to use the potential of agriculture. The middle plane of Lithuania is the area of the most suitable lands for agriculture. The data of Department of Statistics to the Government of the Republic of Lithuania about the produetiviry of yield of cereal crops at the farms at Lithuania shows that the produetiviry of winter wheat is more than 4 Mg ha1. The produetivity of triticale is about 3 Mg ha1. The yield of grain of winter wheat and triticale are inereasing during the last three years. The results of Lithuanian statė plant varieties testing center showed that the potential of yield of winter wheat and triticale could reach higher produetiviry in the middle plane of Lithuania. The hypothesis and calculations that only third part of all winter wheat and triticale grain yield could be used for renewable energy showed 174 000 Mg and 50 000 Mg yield of bioethanol produetiviry. The other part of energy could be received from straw.The intensity of agriculture could be three levels - conventional, sustainable and organic. The yield of cereals depends from intensity of agriculture. The results of field experiments at Valinava showed the similar energy value of biomass of spring barley affected by conventional and sustainable agriculture. The energy of winter wheat biomass is more than spring barley biomass. The earbon amount is 56-57% in the biomass of spring barley and winter wheat affected by all three level of agriculture intensity. It is possibilities get energy 120 GJ ha"1 from earbon of spring barley biomass grown in organic agriculture. The energy from winter wheat is bigger in organic agriculture - from 216 GJ ha"' to 243 GJ ha"1. The energy of spring barley biomass in conventional agriculture is more than 230 GJ haA and more than 400 GJ ha~l of biomass of winter wheat. The data in literature gives one tone of biomass could generate 10-17 GJ of energy. This range make difficult calculation amount of energy of biomass. The output of energy, the balanee of earbon dockside sets the option of crops growing and intensity for bioenergy

CERES‐Maize model performance under mineral and organic fertilization in nemoral climate conditions

Little information is available regarding the performance of the CERES-Maize model under nemoral climate conditions. Therefore, this study aims to estimate and compare major soil-plant N cycle parameters in grain maize (Zea mays L.) crop after application of synthetic and different organic fertilizers solely or in combination in nemoral zone maize production, using the Decision Support System for Agrotechnology Transfer (DSSAT) model. Field experiments carried out during 2015, 2016, and 2017 in Akademija (Lithuania) were considered for model calibration and validation. The model was successfully validated for total aboveground biomass (TAB, R2 = .89), grain yield (GY, R2 = .85), and acceptably for leaf area index (LAI, R2 = .57), total plant N uptake (R2 = .61), and residual soil mineral N (R2 = .64). The lower plant N uptake and soil mineral nitrogen (SMN) observed for the pelletized cattle manure (PCM) and green waste compost (GWC) treatments compared to the fertilization with synthetic ammonium nitrate (AN) were successfully captured by the model. Finally, the model provided reasonable predictions of the temporal dynamics of measured soil water content (SWC) and soil temperature. The validated model was further used to provide N loss estimations during the maize growing seasons via leaching and gaseous emissions. The results showed that the CERES-Maize model can successfully be used to simulate maize growth under the extreme climatic conditions of the nemoral zone in combination with different N managements. Nevertheless, additional efforts are needed to verify and fine-tune the model to comprehensively simulate the N cycle, especially losses by drainage water and gaseous emissions

Relationship between spring barley productivity and growing management in Lithuania’s lowland

Purpose: The current study was aimed to analyse the occurrence of water and nitrogen stress in spring barley and estimate their effects on the crop performance under low-input and conventional management. Materials and methods: Field experiments were conducted during 2007–2009 at the Institute of Agriculture, Lithuanian Research Centre for Agriculture and Forestry on a sandy-loam soil. The management systems were: (a) conventional, with the application of fertilizers and pesticides adjusted to target 5 t ha−1 grain yield; and (b) low-input, without fertilizers and pesticides. Biomass and nitrogen concentration, leaf area index, soil moisture, drainage water runoff and ground water table were measured periodically during the growing season. Results: In all three experimental years, the annual precipitation was close or above the climate normal, but a large part of the rainfall (up to 310 mm) was lost through drainage contributing to the occurrence of temporary moisture deficit in late spring or summer. Water stress resulted in a lower spring barley biomass accumulation rate and lower biomass yield in the years characterized by sub-optimal rainfall distribution. Direct measurements of water retention in the soil and DSSAT model simulations gave relatively good indication of water stress occurrence. Under the low-input management, nitrogen nutrition level was a major constraint for spring barley biomass and grain yield formation. Conclusions: Under Central Lithuania’s conditions, spring barley frequently experiences temporary water stress, because a relatively high proportion of annual precipitation is lost during the non-growing period. This crop can benefit from anticipated increased precipitation and carbon dioxide levels if adequately provided with nitrogen

Thermal Weed Control by Water Steam in Bulb Onions

Bibliogr.: p. 48 (2 pavad.)Vytauto Didžiojo universitetasŽemės ūkio akademij

Žieminių rapsų (C3) ir kukurūzų (C4) konkurencija esant didesnei anglies dioksido koncentracijai ir temperatūrai bei vandens trūkumui

Tyrimo tikslas – įvertinti sausros streso įtaką žieminių rapsų ir kukurūzų konkurencijai, kai aplinkoje buvo didesnė CO2 koncentracija ir temperatūra. Tyrimai atlikti Lietuvos agrarinių ir miškų mokslų centro Sodininkystės ir daržininkystės instituto reguliuojamo klimato kamerose. Eksperimento metu monokultūriniai augalai (100:0) arba žieminių rapsų ir kukurūzų mišiniai (50:50) augo skirtingose aplinkose: 1) esamo klimato sąlygomis, kai temperatūra buvo 21/14 °C dieną/naktį, CO2 – 350 ppm (CO2 T) ir 2) kintančio klimato sąlygomis, kai temperatūra buvo 30/23 °C dieną/naktį, CO2 – 700 ppm (+CO2 T). Abiejose kamerose auginamiems augalams buvo palaikomi du skirtingi substrato drėgnio lygiai. Kukurūzai (C4) konkurencijoje su žieminiais rapsais (C3) išaugino žymiai mažesnį asimiliacinį lapų plotą ir sukaupė šviežios masės kiekį, palyginus su monokultūriniais augalais abiejose aplinkose (CO2 T ir +CO2 T), o neigiamą įtaką dar sustiprino nepakankamas kiekis vandens. Lyginant žieminių rapsų ir kukurūzų monokultūrinius augalus, +CO2 T veiksniai, kai substrate buvo pakankamas kiekis drėgmės, turėjo žymią teigiamą įtaką kukurūzų asimiliacinio ploto augimui (padidėjo ~21%) ir masės kaupimuisi (padidėjo ~22%). Kai substrate buvo nepakankamas kiekis vandens, žieminių rapsų ir kukurūzų monokultūriniai augalai, nepriklausomai nuo aplinkos, išaugino žymiai mažesnį asimiliacinį lapų plotą ir sukaupė žalios masės. Vandens trūkumas substrate skatino kauptis chlorofilus lapuose žieminių rapsų, kurie augo kaip monokultūra arba konkuruodami su kukurūzais. Nustatytas reikšmingai sumažėjęs chlorofilo a kiekis kukurūzų monokultūrinių augalų lapuose +CO2 T aplinkoje, kai vandens kiekis substrate buvo pakankamasThe aim of this study was to estimate the effects of drought stress under elevated CO2 and temperature on the competition between winter rape and maize plants. The experiment was conducted in a controlled-environment growth chamber at the Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry. Plants grown in monoculture (100:0) or in mixture (winter rape:maize, 50:50) irrigated and non-irrigated (drought stress), were exposed to ambient environment conditions – day/night temperature 21/14°C, CO2 – 350 ppm (CO2 T), and enhanced environment conditions – day/night temperature 30/23°C, CO2 – 700 ppm (+CO2 T). Maize (C4) grown in mixture with winter rape (C3), had significantly smaller assimilating leaf area and produced less fresh mass at CO2 T and +CO2 T, as compared to monoculture, and water deficit strengthened the negative effect. Comparison of the data obtained for monoculture revealed that elevated CO2 and temperature in the conditions of sufficient moisture supply had significantly positive effect on maize assimilating leaf area (increased ~21%) and fresh mass accumulation (increased ~22%). Assimilating leaf area and fresh mass of winter rape and maize monocultures significantly decreased in response to water deficit both at CO2 T and +CO2 T. Water shortage had a stimulating effect on chlorophylls in leaves of winter rape in monocultures and mixtures. At +CO2 T and sufficient water supply, maize in monoculture and mixture with rape significantly reduced the content of chlorophyll a. Carotenoid content significantly decreased in maize leaves (monoculture and mixture) under +CO2 T in both irrigated or non-irigated substrates. Winter rape, in monoculture and mixture, accumulated significantly higher content of carotenoids under water deficit and ambient CO2 T. However, a significant decrease in carotenoids was determined in rape leaves under +CO2 TLietuvos agrarinių ir miškų mokslų centro Sodininkystės ir daržininkystės institutasLietuvos agrarinių ir miškų mokslų centro Žemdirbystės institutasVytauto Didžiojo universitetasautŽemės ūkio akademij

Effect of simulated frost on biometrics indices of agricultural plants

Vegetaciniai bandymai atlikti 2008 metais Lietuvos sodininkystės ir daržininkystės instituto Augalų fiziologijos laboratorijos fitotroniniame komplekse. Tirta: vasarinis miežis (Hordeum vulgare L.) ‘Luokė’, vasarinis rapsas (Brassica napus L.) ‘Mascot’, ankstyvoji bulvė (Solanum tuberosum L.) ‘Satina’ ir trys sėjamojo žirnio (Pisum sativum L.) veislės – ‘Pinochio’, ‘Gloriosa’, ‘Cud Kelvedonu’. Augalai šaldyti dvi ir keturias dienas, imituojant 3,5 valandos trukmės šalnas. Dviejų ir keturių dienų trukmės šalnos skirtingai paveikė tirtų augalų augimo rodiklius. Miežių augimą neigiamai paveikė tiek dviejų, tiek keturių dienų šalnos, o rapsų ir bulvių augimą sutrikdė ilgiau trukusios (keturių dienų) šalnos. Žirnių reakcija į šalnų sukeltą stresą priklausė nuo genotipo. Keturių dienų šalnos stabdė žirnių veislių ‘Gloriosa’ ir ‘Cud Kelvedonu’ augalų augimą, o veislės ‘Pinochio’ augimo rodikliams neturėjo įtakosThe object of this study was to evaluate the effect of simulated late frost on growth indices of agricultural plants. Vegetative experiments were carried out in Laboratory of plant physiology, in phytotron complex at the Lithuanian Institute of Horticulture in 2008. Investigated agricultural plants: Hordeutn vulgare L. var. 'Luoke', Brassica napus L. var. 'Mascot', Solarium tuberosum L. var. 'Satina', Pisum sativum L. var. 'Pinochio', var. 'Gloriosa' and var. 'Cud Kelvedonu'. Under frost effect plants were treated for two and four days, simulating frosts of three and a half hour. Different influence on plants growth indi¬ces of two and four day's frosts was observed. Analysing growth of barley negative affect of both two and four day's frost was observed. However, only long lasting (4 days) frosts negatively influenced growth of rapes and potatoes. The reaction of peas to stress depended on their genotype. Four days long frosts stopped the growth of pea's var. 'Gloriosa' and var. 'Cud Kelvedonu', whereas frost didn't influenced the growth indices of peas var. 'Pinochio'Vytauto Didžiojo universitetasŽemės ūkio akademij