Year: 2019
Type: dissertation
Abstract: In the urge to mitigate the negative impact of weeds, like reduced yields, both agricultural and \nhorticultural production have heavily relied on herbicides for weed control. This has led to \nvast environmental problems like human health risks and negative impact on biodiversity. \nConsequently, other measures relying more on the ecological properties controlling weeds \nhave been explored. One such attribute is the competitive ability of crops. Intercropping is \none method of increasing the competitive ability of crops against weeds regarding acquisition \nof light, nutrients and space. Field pea, Pisum sativum, and spring barley, Hordeum vulgare, \nare a good combination for intercropping with weed suppression effect. Sole cropping of oat, \nAvena sativa, has also a highly competitive ability against weeds. The weed seed bank is the \nviable weed seeds in the soil and evaluation of its composition can give indications of soil, \ncrop and weed management. The aim of this thesis is to examine the weed seed bank of \norganic crop rotations in Alnarp, Sweden. The aim is also to see if there is an impact of \nintercropping of pea and barely on the weed seed bank compared to sole cropping of pea and \noats and the weed management technique black fallow. The most abundant species in the \nweed seed bank in the organic crop rotations in Alnarp were similar with two other seed \nbanks related to organic crop rotation in Scandinavia. The Alnarp seed bank had however a \nhigher species richness. Analysis could not detect any significant difference in impact from \nthe treatments intercropping pea+barley, sole crop pea, sole crop oat and black fallow on the \nweed seed bank. In the present study it was concluded that weed seed bank assessments could \nbe an uncertain method if the treatments have similar characteristics and the assessment is \ndone after only one cropping season. Treatments that have similar characteristics need to go \non for a longer time for the effects to be visible in analysis. However, this study constitutes a \ngood baseline for future research on the weed seed bank and the impact from intercropping \nand sole cropping.
Author: Harald Helgesson
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDGs: Life on land, Zero hunger
Open Access status: green
OpenAlex ID: W2991486924