Abstract
The use of herbicides amongst smallholder farmers is minimal because herbicides are expensive and they require specialized application equipments. Weeds are problematic in conservation agriculture where herbicides are expensive for smallholder farmers. The use of cover crops can help to suppress weed growth and development by creating an environment which is not suitable for weeds survival. Cowpea (Vigna unguiculata (L.) Walp) dolichos lablab (Lablab purpureus L.) and velvet bean (Mucuna pruriens (L.) DC) were evaluated for biomass accumulation and weed suppression under conservation agriculture system in two contrasting experimental sites: Ukulinga and Bergville in KwaZulu-Natal. Bare plot and herbicide treatments served as controls. Treatments were laid in a randomized complete block design, replicated three times. Mucuna pruriens (L.) DC had the highest biomass accumulation in both sites Bergville (0.72 t/ha) and Ukulinga (1.59 t/ha). Cowpea had the lowest biomass accumulation in Bergville (0.59 t/ha) and lablab was the lowest in Ukulinga (0.88 t/ha). Lablab was effective in suppressing weed biomass in Bergville (P < 0.05). Cowpea performed best in suppressing weed biomass in Ukulinga (P < 0.05). The results suggest that cowpea and lablab can be effective for weed suppression and therefore can be recommended for use in conservation agricultural systems.
Highlights
Frequent tillage with a moldboard, which is normally called conventional tillage, may lead to soil degradation
The results suggest that cowpea and lablab can be effective for weed suppression and can be recommended for use in conservation agricultural systems
The highest biomass accumulation by velvet bean was attributed to its robust growth habit which allowed it to do best in acidic soils
Summary
Frequent tillage with a moldboard, which is normally called conventional tillage, may lead to soil degradation. This degradation is in form of soil erosion, soil compaction and destruction of soil aggregates (Hamza and Anderson, 2005). Land degradation can cause low crop yields and an interest by South African smallholder farmers to adopt conservation agriculture. Conservation agriculture has a potential to improve crop yields, reduce soil erosion and improve soil fertility (Giller et al, 2009). Weed management is a problem in conservation agriculture compared to conventional tillage. This is attributed to deep burial of weed seeds by conventional ploughing and reduced seed germination as compared to conservation agriculture which leaves weed seeds on the surface and allow weeds to germinate (Singh et al, 2015)
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
