|Shrefler, James - OSU, LANE, OK|
Submitted to: Proceedings of Horticultural Industry Show
Publication Type: Proceedings
Publication Acceptance Date: February 1, 2004
Publication Date: March 1, 2004
Citation: Webber III, C.L., Shrefler, J.W. 2004. Black bean production: Cover crops, tillage, and weed competition. Proceedings of Oklahoma and Arkansas Horticultural Industry Show. p. 171-175. Interpretive Summary: It is understood that cover crops can reduce soil erosion by protecting the soil surface and enhance soil tilth, soil moisture, and nutrient availability by increasing soil organic matter. The question is "Which winter cover crop will promote the best growth and yield for spring planted crops?" Our research compared the effect of four winter cover crops, barley, oats, rye, and wheat, and no cover crop to determine which would be best for a spring-planted dry bean crop. The research was repeated twice. The winter cover crops were planted in late September of 1999 and 2001. 'Black Knight' black beans were planted May 10 of 2000 and 2002. The study was conducted on a fine sandy loam soil at the USDA and Oklahoma State University research station at Lane, OK (southeast Oklahoma). In this research we also studied the best time to remove weeds. Black beans grew best when planted after barley (485 lb/ac), rye (448 lb/ac), and oats (401 lb/a). The worse black bean yields were produced when planted after wheat (270 lb/a) or no cover crop (322 lb/a). In addition to producing lower seed yields, the beans planted after wheat and no cover crops also produced bean plants with fewer seeds per pod and pods per plant. It was also discovered that early season weed control is nearly as important as full season weed control, and far more beneficial than receiving only late season weed control. Any weed removal (early, late, or full season) was better than no weed control. In conclusion, this research showed that the best dry bean yields were achieved when planted after barley, rye, or oats, and received early or full season weed control. Producers can protect and enhance their soils, and increase dry bean yields by using these research results to select the best winter cover crops.
Technical Abstract: Winter cover crops can reduce soil erosion by protecting the soil surface and enhance soil tilth, soil moisture, and nutrient availability by increasing soil organic matter. Winter cover crops can also interact with the tillage/planting and weed control system to improve spring planted crops. The objective of this research was to determine the effect of winter cover crops, tillage/planting systems, and weed control on black bean yield components. A two-year field study was conducted at Lane, OK (southeast Oklahoma), on a Bernow fine sandy loam, 0 - 3% slope, (fine-loamy, siliceous, thermic Glossic Paleudalf). The research included five winter cover crop treatments (barley, oats, rye, wheat, and "none" (no winter cover crop)), two spring tillage/planting systems, four weed control treatments, and four replications. Following the planting of black beans (Phaseolus vulgaris L.) cv. 'Black Knight' at Lane, OK on May 24 (2000 and 2002), four weed control treatments were evaluated, including a "weedy check" (no weed removal), an "early season" (weed removal for first 45 days), a "late season" (weed removal for last 45 days), and a "full season" treatment (weed removal during the entire 90 day growing season). At harvest an 8 ft length of plant row was harvested and used to determine seed yield (lb/a), pod number (pods/plant), seed number (seeds/pod), seed weight (g/100 seeds), and plant populations (plants/a). When averaged across years, tillage/planting systems, and weed control levels, the black beans following barley (485 lb/ac), oats (401 lb/a), and rye (448 lb/ac) produced greater yields than either wheat (270 lb/a) or no cover crop (322 lb/a). Early and full season weed control produced greater seed yields, pods per plant, seeds per pod, seed weight, and plant populations than the weedy check. Any weed removal (early, late, or full season) was better than no weed control. The results indicate that barley, oats, and rye were better for spring planted black bean production and early season weed control is nearly as important as full season weed control, and far more beneficial than a crop receiving only late season weed control.