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

Kalio išplova iš karbonatingo giliau glėjiško rudžemio, esant skirtingam kiekiui kritulių ir taikant įvairias žemdirbystės sistemas

The aim of this research was to compare a few crop management systems in respect of potassium leaching in order to reduce the leaching losses. Research was carried out on an Endocalcari-Endohypogleyic Cambisol (CMg-n-wcan) at the experimental site of Lithuanian Institute of Agriculture (currently – Institute of Agriculture, Lithuanian Research Centre for Agriculture and Forestry). The focus was on the search for factors responsible for leaching, including precipitation amount and rate, and selected soil properties. The highest potassium cation (K+) leaching with drainage runoff 3.8 kg ha-1 year-1 was determined in the conventional system with high K inorganic fertilization level as compared with 1.9 kg ha-1 year-1 in the treatment with zero fertilization (reference) during the first research period in 1995–1999. However, later, after a few changes in experimental design and under the drier conditions, leaching of K+ was low and similar in all crop management treatments on the arable plots (approx. 1.6 kg ha-1 year-1). The rate of K and N fertilizers positively influenced the leaching of K+ only during the normal and wet years with precipitation rate >450–600 mm. The content of soil aggregates <0.25 mm in topsoil positively correlated with K+ leaching losses during the first research period (P < 0.01). During the whole research period the precipitation rate was the factor from the main effects, which explained 64% of the K+ leaching variance. The final model explained 76% of K+ leaching variance for all data and 65 ± 16% on cross-validation data, showing relatively high and stable accuracy of predictions. Among the variables, the interaction of precipitation rate and content of humus, the interaction between the precipitation rate and content of soil aggregates <0.25 mm were the most important, each explaining more than 60% of the variance of K+ leaching losses

Paprastojo kiečio (Artemisia vulgaris L.) bei geltonžiedžio legėsto (Silphium perfoliatum L.) produktyvumo ir kietojo kuro ruošimo technologinis vertinimas

Tyrimai atlikti siekiant nustatyti dirvožemio pH (arba kalkinimo) ir tręšimo azoto trąšomis įtaką paprastojo kiečio (Artemisia vulgaris L.) ir geltonžiedio legėsto (Silphium perfoliatum L.) sausosios masės (SM) derliui, šilumingumui ir mechaninėms savybėms. Lauko bandymai įrengti 2008 m. Vakarų Lietuvoje, natūraliai rūgščiame (pH 4,2–4,4) moreniniame priemolyje. Remiantis vidutiniais ketverių metų tyrimų duomenimis, kiečių didžiausias SM derlius buvo nustatytas 2009 m. – 4100 kg ha-1, kuris esmingai sumažėjo vėlesniais tyrimų metais, o legėstų didžiausias SM derlius buvo gautas 2011 m. – vidutiniškai 17980 kg ha-1. Dirvožemio pH padidėjimas nuo 4,2–4,4 iki 5,6–5,7 (pakalkinus 6,0 t ha-1 CaCO3) legėstų SM prieaugį padidino 27,4 %. 120 kg ha-1 N trąšų panaudojimas iš esmės padidino bendrą kiečių ir legėstų SM derlių – atitinkamai 34,5 ir 26,7 % daugiau nei netręšiant. Tirta paprastųjų kiečių ir geltonžiedžių legėstų smulkinimo kokybė bei pjaustinio frakcinė sudėtis pagal Europos Sąjungos šalyse taikomą metodiką, naudojant sietus su skirtingo skersmens skylutėmis. Nustatyta, kad geltonžiedžių legėstų pjaustinys buvo smulkesnis ir tolygesnis, labiau tinkantis naudoti energetinėms reikmėms. Vertinant tirtų augalų malimo kokybę nustatyta, kad geltonžiedžių legėstų miltų dalelės buvo smulkesnės ir tolygesnės, todėl šie augalai labiau tinka presuoti ir naudoti deginimui. Didžiausias vidutinis paprastųjų kiečių biomasės šilumingumas siekė 17,97 MJ kg-1 (2010 m.), o geltonžiedžių legėstų – 17,48 MJ kg-1 (2012 m.). Abiejų augalų šilumingumo reikšmėms didžiausią įtaką turėjo augimo metai ir 120 kg ha-1 azoto trąšų panaudojimasThe research was carried out to determine the effects of soil pH (or liming) and nitrogen (N) fertilization on the common mugwort (Artemisia vulgaris L.) and cup plant (Silphium perfoliatium L.) dry mass (DM) yield, calorific value and mechanical properties. Field experiments were set up in 2008 in Western Lithuania on a naturally acid (pH 4.2–4.4) moraine loam. According to the averaged data of four experimental years, the highest DM yield 4100 kg ha-1 of common mugwort was established in 2009, which significantly decreased in the subsequent years. And, conversely, the highest cup plant DM yield 17980 kg ha-1 was obtained in 2011. An increase in soil pH from 4.2–4.4 up to 5.6–5.7, resulting from 6.0 t ha-1 CaCO3 application, increased cup plant DM yield by 27.4%. Fertilization with 120 kg ha-1 N significantly increased common mugwort and cup plant DM yield by 34.5% and 26.7% respectively, compared with the treatment without N fertilization. We also studied the chopping quality of common mugwort and cup plant and chaff fractional composition using sieves with different mesh sizes. The chaff of cup plant was finer and more even, and thus more suitable for use for energy purposes. Plant milling quality showed cup plant particles to be smaller and more even too, and thus better suited for pressing and combustion. The highest calorific value of common mugwort (17.97 MJ kg-1) was obtained in 2010 and that of cup plant (17.48 MJ kg-1) in 2012. The calorific values of common mugwort and cup plant were influenced most by the year of cultivation and 120 kg ha-1 N applicationVytauto Didžiojo universitetasŽemės ūkio akademij

Winter wheat leaf area index under low and moderate input management and climate change

With global warming, winter wheat growth conditions and production potential is changing, thus adjustments in management are necessary to optimize input levels under new environments. The aim of this study was to estimate winter wheat leaf area index changes as affected by low and moderate input management and climate change. Field experiments were carried out during 2007-2009 at the Institute of Agriculture, Lithuanian Research Centre for Agriculture and Forestry in Dotnuva, Kėdainiai, Lithuania. Winter wheat cultivar ‘Ada’ was grown under two input levels: moderate (conventional) where herbicides, fungicides, insecticides and industrial fertilizers (N110P90K140) were applied, and low (organic), without industrial fertilizers and plant protection products. Winter wheat leaf area parameters were simulated with the computer model DSSAT v4.0.2.0. The weather data (daily maximum and minimum air temperature and precipitation) were obtained from Dotnuva and solar radiation from Kaunas weather stations. Winter wheat leaf area index (LAI) in field experiments, despite the contrasting weather conditions among years, followed a similar pattern; however, with marked differences between input levels. The relatively low nitrogen concentration in plant biomass at the beginning of intensive growth period indicates nitrogen nutrition to be a major limiting factor for LAI, leaf area duration (LAD) and grain yield. Simulation with the DSSAT model according to the scenarios where weather, on daily bases, is +2ºC warmer, but the amount and distribution of precipitation are same as during the experimental years, a shift of LAI maximum to earlier dates in spring can be expected; however, without considerable changes in leaf area index (LAI) maximum and leaf area duration (LAD). It is likely that LAI maximum values both under low and moderate input will be limited by nitrogen supply and will be on the level of 3 and 5 m2 m-2, respectivelyVytauto Didžiojo universitetasŽemės ūkio akademij

Predicting of winter wheat productivity in different agro ecosystems as affected by climate change

Vytauto Didžiojo universitetasŽemės ūkio akademij