Variety and weed management effects on organic chickpea stand establishment and seed yield

Authors: Mohammed, Yesuf; MILLER, ZACHARIAH - Montana State University; HUBBEL, KYRSTAN - Montana State University; CHEN, CHENGCI - Montana State University

Submitted to: Agrosystems, Geosciences & Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/6/2020
Publication Date: 4/1/2020
Publication URL: https://handle.nal.usda.gov/10113/6937454
Citation: Mohammed, Y.A., Miller, Z., Hubbel, K., Chen, C. 2020. Variety and weed management effects on organic chickpea stand establishment and seed yield. Agrosystems, Geosciences & Environment. 3:e20035. https://doi.org/10.1002/agg2.20035.
DOI: https://doi.org/10.1002/agg2.20035

Interpretive Summary: People’s interest in consuming organic products is increasing worldwide but weed control in organic legumes like chickpea (Garbanzo) can be challenging. Integrated management practices are needed to reduce weed competition and improve yields. The objective of this study was to determine the effects of chickpea varieties (CDC Orion and Black Butte), seeding rate (standard seeding rate and 50% increase from the standard seeding rate) and two pre-emergence weed control measures (flame weeding and shallow tillage). The study was established at two locations (Sidney and Corvallis) in Montana, USA. The results revealed that choice of variety make a great difference in terms of chickpea emergence, weed suppression, and grain yield. Black Butte chickpea produced more grain yield than CDC Orion. Increasing seeding rate for the Black chickpea increased grain yield by 26% than standard seeding rate and reduced weed biomass as well. Flaming increased chickpea grain yield only at Corvallis. The use of increased seeding rate with shallow tillage reduced weed biomass. Shallow tillage, if properly implemented, helps to uproot early germinating weeds but one must check the depth and timing of this tillage to avoid damage to emerging chickpea seedlings. The results also indicated the importance of developing chickpea varieties targeted for organic production. This result provides information for producers interested in growing organic chickpea, and benefits extension specialists, other researchers and consultants advising organic chickpea production.

Technical Abstract: The need for organic produce is increasing worldwide but weed control remains a critical problem for organic crop production. Three types of weed control practices were evaluated for two organic chickpea (Cicer arietinum L.) varieties at the Western (Corvallis) and Eastern (Sidney) Agricultural Research Centers of Montana State University. Treatments included two chickpea varieties (Black and CDC Orion chickpeas), two seeding rates (standard seeding rate or 1× at 43 seeds m-2 and 50% increase over the standard rate or 1.5×), and two pre-emergent weed control practices (flame weeding and shallow tillage). Results revealed that Black chickpea was associated with greater stand densities and grain yield with lower weed biomass than CDC Orion. Increasing seeding rate for Black chickpea improved crop density and increased grain yield to the extent of 26% compared with the standard seed rate. Flaming increased chickpea grain yield only at Corvallis in 2016. The combined effects of shallow tillage and increased seeding rates resulted in reduced weed biomass. Shallow tillage can be successfully integrated to improve yields and reduce weed pressure in organic chickpea. However, precaution must be taken for the tillage timing to avoid damage to emerging chickpea seedlings. More research is needed to select chickpea varieties that have improved vigor and are more competitive to weed pressure commonly seen in organically-managed fields.