Markku Kontturi

Soil Respiration in Three Soil Types in Agricultural Ecosystems in Finland

Seasonal changes in soil respiration (SR), soil temperature (ST) and soil water content (SWC) were monitored in three different soil types (peat, sand and clay soils) in Finnish agricultural ecosystems. Rates of CO2 emission were measured by the closed chamber method using an infrared gas analyser (IRGA) at intervals of 2-3 weeks from May to October. The seasonal changes in SR were different among the soil types: peat soil, maximum rate (650 mg CO2 m-2 h-1) in summer, positive significant relation between SR and ST and negative relation between SR and SWC; sandy soil, stable SR (300 mg CO2 m-2 h-1) without seasonal changes, positive relation between SR and SWC and no significant relation between SR and ST; clay soil, maximum rate (500 mg CO2 m-2 h-1) in summer, highly positive significant relation between SR and ST and negative relation between SR and SWC. A statistical model was developed to predict the amount of CO2 evolved from the cultivated soils based on the relationships between SR and certain abio...

Contents of trichothecenes in oats during official variety, organic cultivation and nitrogen fertilization trials in Finland

. The differences in DON concentrations between organic and conventional cultivation were small. The results showed also that the use of various nitrogen fertilization levels only slightly affected the trichothecene concentrations. The contents of trichothecenes in Finnish grains appeared to be similar to or lower than those reported earlier in the Northern Hemisphere.

Selenium content of Finnish oats in 1997-1999: effect of cultivars and cultivation techniques

-1 dw. Considerable regional and seasonal variations existed. The Se contents of oats were significantly higher in 1999 probably due to the combined effect of not increased fertilizer level (from 6 to 10 mg Se kg -1 fertilizer) and very low precipitation in 1999. The Se contents of oats were significantly lower in organic cultivation, due to the absence of Se-supplemented fertilization. Sig- nificant (P < 0.001) cultivar differences were detected in official variety trials. The cultivars Veli and Leila showed higher levels of Se.

Pea-oat intercrops to sustain lodging resistance and yield formation in northern European conditions

Abstract Locally produced crop protein is urgently needed in Europe. Pea is a good protein source and is well adapted to northern conditions. Pea can fix nitrogen that the following crop in rotation can benefit from. In cereal-dominated cropping systems pea is a break crop disrupting the life cycle of cereal diseases, leading to less fungicide application and thereby minimizing off farm inputs and benefiting the environment. Grain legumes provide animals with protein and energy, and the seeds of pulse crops are complementary to those of cereals. Field peas can be cultivated in most parts of Scandinavia and interest in peas has increased for inclusion in organic farming. Growing pea as a sole crop is a challenge since its stem is prone to lodging thereby resulting in harvesting difficulties, reduced yield and decreased profits. Intercropping of pea with oat could minimize the above listed problems but to our knowledge proportion of seeds mixture of the two crops and selection of pea cultivars without compromising the pea yield, especially protein production, at high latitudes conditions is limited. Therefore, our objective was to evaluate performance of sole cropped pea (Karita, Perttu, Hulda) and oat (seed proportions 7.5% and 15%) and their intercrop combinations and establish an appropriate seed mixture for a pea–oat intercropping systems that prevents lodging without markedly reducing pea yield. Field experiments were conducted at three locations (Jokioinen, Mietoinen, Ylistaro) of the Agrifood Research Finland in 2002–2004. Intercropping peas with oats prevented peas from lodging and made their harvest easier. Optimal numbers of oats in pea intercrops were difficult to determine, varying according to pea cultivar and local growth conditions. Excess oats in the seed mixture or conditions favouring oat growth prevented peas from lodging but pea yield was decreased.