Integration of Cover Crop, Conservation Tillage, and Low Herbicide Rate for Machine-harvested Pickling Cucumbers

Abstract

The effects of two cover crops [cereal rye (Secale cereale L.) and oat (Avena sativa L.)], four tillage systems [no tillage (NT), strip tillage (ST), conventional tillage with cover crops incorporated (CTC), and conventional tillage without cover crop (CTN)], and three pre-emergence herbicide rates (full rate, half rate, and no herbicide) on pickling cucumber (Cucumis sativus L.) growth and production, weed populations, and the incidence of pythium fruit rot were studied. Weed infestations, cucumber establishment, and cucumber leaf chlorophyll content were similar between the rye and oat treatments. However, the oat treatment had higher cucumber fruit number and weight and a lower percentage of cucumber fruit infected with Pythium spp. compared with the rye treatment. The NT and CTC systems reduced cucumber stand and leaf chlorophyll content, but had equivalent cucumber fruit number and weight compared with CTN. The NT and ST had lower weed biomass and weed density than CTN and CTC. The NT also reduced the percentage of cucumber fruit affected with pythium compared with CTN and CTC. Reducing the pre-emergence herbicide rate by half did not affect weed control or cucumber fruit yield compared with the full rate. However, weeds escaping herbicide application were larger in the half-rate treatment. The experiments indicate that with the integration of cover crops and conservation tillage, it is possible to maintain cucumber yield while reducing both herbicide inputs (by 50%) and the incidence of fruit rot caused by Pythium spp. (by 32% to 60%).

Weed Ecology and Nonchemical Management under Strip-Tillage: Implications for Northern U.S. Vegetable Cropping Systems

“…For example, Barralis and Chadoeuf (1980) observed 12% total emergence of germinable weed seeds following tillage compared with 8% from undisturbed soil. Likewise, reduced emergence of weeds under ST, compared with CT, systems has been observed in pickling cucumber (Wang and Ngouajio 2008), carrot (Brainard and Noyes 2012), corn (Hendrix et al 2004), and cabbage (Haramoto and Brainard 2011).…”

“…Unfortunately, very few empirical studies have examined differences in growth and fecundity of individual weeds in the distinct BR and IR zones of ST systems, relative to that in CT or NT systems. Wang and Ngouajio (2008) reported that individual weed biomass in processing cucumber was twice as great under ST, compared with CT, management. This result may have been due, in part, to lower weed emergence under ST systems, resulting in less competition between weeds in ST, compared with CT, systems, rather than because of improvements in edaphic conditions regulating weed growth under ST management.…”

“…ST has been shown to reduce fuel and labor costs, protect soils, and maintain crop yields in vegetable crops including sweet corn (Luna and Staben 2002;Luna et al 2012;Brainard et al 2012b), winter squash, snap beans (Bottenberg et al 1999;Brainard et al 2012a), carrots (Brainard and Noyes 2012), cabbage (Brassica oleracea var. capitata L.) (Haramoto and Brainard 2012;Hoyt et al 1996;Mochizuki et al 2007;Mochizuki et al 2008), garden cucumber (Cucumis sativus L.) (Lonsbary et al 2004;Wang and Ngouajio 2008), and broccoli (Brassica oleracea L. var. botrytis L.) (Luna et al 2012).…”

Evaluating pest-regulating services under conservation agriculture: A case study in snap beans

“…In general, RT systems result in lower rates of weed emergence, but higher rates of seedling survival. For example, reduced emergence of weeds under strip-till (ST), compared with full-width tillage (FWT), has been observed for summer annual species in pickling cucumber (Wang and Ngouajio, 2008), carrot (Brainard and Noyes, 2012), and corn (Hendrix et al, 2004). In contrast, weed seedling survival-particularly of winter annual or perennial species-is typically higher under RT systems, since tillage is not used to sever, uproot or bury seedlings .…”

Age-related Resistance of Diverse Cucurbit Fruit to Infection by Phytophthora capsici

“…Rotation to a nonhost crop is of limited value because oospores of P. capcisi can survive in the soil for a long period of time, up to 10 years (Hausbeck and Lamour, 2004). Wider plant spacing, cover crops, trellises, or variant architectural phenotypes may help to control the disease by facilitating better fungicide coverage, modifying the microclimate, or reducing contact with the inoculum-containing soil, thereby facilitating disease avoidance (Ando and Grumet, 2006;Ngouajio et al, 2006;Ristaino et al, 1997;Wang and Ngouajio, 2008). However, these methods can be difficult to implement in a commercial setting.…”