The interactions between nitrogen dose, year and stage of ripeness on nitrogen and trace element concentrations and seed‐borne pathogens in organic and conventional wheat

Abstract

The effects of N dose and stage of ripeness on Fe, Co, Cr, Ni, Se and N concentration and incidence of fungal diseases were measured in winter wheat grain from conventional (CONV) and organic (ORG) systems on neighbouring areas of a 10-year-old manure-based farm. Principal components analysis (PCA) of the data showed that year had the greatest influence on the results, but that cropping system affected N, Ni, Fe and Se content and incidence of diseases. Attack by Dreschlera tritici-repentis was highest in ORG and attack by Stagonospora nodorum in CONV. Increasing stage of maturity increased incidence of fungal disease and Fe content. Analysis of variance and MANOVA showed that wheat yield was affected by weather (precipitation and temperature), cropping system and N dose. The 10% lower yield in ORG than CONV was explained by a lower amount of plant available N at the same N dose. Nitrogen, Fe, Ni, Se and Co contents in grain were affected by year, while dry matter content was significantly lower in ORG than in CONV. The MANOVA identified correlations between Co and Fe, Ni and Se. Incidence of fungal diseases was foremost affected by weather, stage of ripeness and N dose. Organic cropping increased Fe and Se uptake and decreased S. nodorum attack, but increased attack by D. tritici-repentis.

Influence of mechanical weeding and fertilisation on perennial weeds, fungal diseases, soil structure and crop yield in organic spring cereals

“…Increased N rates have been shown in a number of studies to increase fusarium head blight, wheat leaf spot complex, barley net blotch, powdery mildew, rust diseases, etc (e.g. Lemmens et al 2004;Baeckström et al 2006;Askegaard et al 2011;Salgado et al 2017). In our study, we did not see a significant effect of nitrogen fertilisation on fungal disease levels, although there was a trend towards increased disease with increased N supply.…”

“…As commented by a number of studies, cereal diseases are greatly influenced by weather conditions in the growing season (e.g. Baeckström et al 2006;Walters and Bingham 2007). In our experiments, it is likely that weather conditions late in the growing season caused considerable development of barley net blotch and oat leaf spot infections evenly dispersed throughout the experimental fields.…”

Effects of organic and conventional production systems and cultivars on the technological properties of winter wheat

“…Therefore it is important to study those parameters of different wheat varieties grown under organic conditions 3. It is known that grain grown under organic farming has lower protein content than the conventionally grown crop 4, 7. Consequently, it is important to have varieties well adapted to organic growing conditions.…”

Cultivar and Nitrogen Fertiliser Effects on Fresh and Stored Winter Wheat Grain Quality Indices

“…Quality parameters of winter wheat are not stable between production years because of changes in factors such as initiation of the growing season, distribution of rainfall and heat units available for crop growth during corresponding phases of plant growth and development (Cesevièienë et al, 2009). Addition of nitrogen fertiliser in accordance with the plant requirement is necessary to attain high yields and quality of winter wheat (Ragasits, 2000;L-Baeckström et al, 2006).…”