The impact of allelopathic winter rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth) residues on a vegetable cropping system

Experiments were conducted to determine the effect of allelopathic cover crops on a vegetable cropping system. A study was also undertaken to investigate the impact of cover crop residues on weed management. Winter rye (Secale cereale L. cv. Wheeler) and hairy vetch (Vicia villosa Roth cv. Oregon Crown) were interseeded in the fall. The following spring, cabbage (Brassica oleracea var. Capitata L. cv. Bravo), tomato (Lycopersicon esculentum Mill. cv. Market Pride) and snap bean (Phaseolus vulgaris L. cv. Mustang) were planted into cover crops that had been either desiccated with glyphosate (N-(phosphonomethyl)glycine) at 1.1 kg a.i ha$\sp{-1}$ (RT) or mowed and disked (Disked). Both methods left cover crop residue on the soil surface. A preplant incorporated application of trifluralin (2,6-dinitro-N,N--dipropyl-4-(trifluoromethyl)benzenanine) at 0.8 kg ha$\sp{-1}$ to bare ground was included as a conventional tillage (CT) control. Fifty percent of cover crop residues in RT persisted 12 wk in 1991, but only 6 wk in 1992, an unusually wet summer. In 1991, the decrease in residue mass during the growing season was linear. The greatest snap bean yields were in CT; total yields of cabbage and tomato were not affected by management system. However, early tomato yield was greater in the RT treatment than in the disked or CT production systems. In 1992, the greatest yields for cabbage and snap bean were in CT. Cabbage plants in the disked and CT treatments had significantly greater infestations of diamondback moth, imported cabbageworm, and cabbage looper than in RT plots. Rye and hairy vetch residues also inhibited weed growth. Redroot pigweed (Amaranthus retroflexus L.) accounted for 60 to 80% of the total weeds. Initial (2 wk) weed control in 1991, was poorest in the disked plots and was similar in RT and CT treatments. In 1992, all treatments were weedy. The RT treatment tended to have fewer grasses than the disked treatment.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Crop Sciences

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Mwaja, Vasey Nyamu

Contributors dc:contributor

• Masiunas, John B.

• Agriculture, Agronomy
• Agriculture, Plant Culture
• Agriculture, Plant Pathology

Statement dc:rights

• Copyright 1994 Mwaja, Vasey Nyamu

Language dc:language

eng

Identifier

AAI9416413
(UMI)AAI9416413

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/21455