Effects of relay cover crop planting date on their biomass and maize productivity in a sub-humid region of Zimbabwe under conservation agriculture

One of the primary production challenges red raspberry (Rubus idaeus) growers in the Pacific northwestern United States confront is root lesion nematode [RLN (Pratylenchus penetrans)]. In this perennial production system, red raspberry serves as a sustained host for RLN. When a red raspberry planting is slated for removal in the fall, a new red raspberry planting quickly follows in the same field the following spring. The primary crop that occurs in rotation with red raspberry is a winter wheat cover crop to provide soil coverage and protection during the winter. The objectives of this research were to determine if winter wheat (Triticum aestivum) provides a green bridge for RLN in continuous red raspberry production systems and to determine if modified winter cover cropping practices can be used to reduce population densities of RLN before replanting red raspberry. Four trials were established in fields being replanted to red raspberry and the following modified winter cover cropping practices were considered: cover crop planting date (at fumigation or 2 weeks after fumigation), termination date (cover crop kill with herbicide 2 or 6 weeks before incorporation compared with the industry standard of incorporation immediately before planting), and the additional application of methomyl. ‘Rosalyn’ and ‘Bobtail’ winter wheat planted as cover crops in these trials were demonstrated to be maintenance hosts for RLN (ranging from 10 to 947 RLN/g winter wheat root across trials) allowing them to be a green bridge for RLN to infect the following red raspberry crop. Altering winter wheat cover crop planting date, termination date with herbicide, or methomyl application did not affect RLN population densities in the subsequent red raspberry crop. Although planting an RLN maintenance host may be of concern to growers, the advantages of reduced soil erosion and nitrate leaching associated with cover cropping outweigh the perceived risk to the subsequent red raspberry crop.

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Tillage and Planting Date Effects on Weed Dormancy, Emergence, and Early Growth in Organic Corn

Weed Science ◽

10.1614/ws-d-14-00112.1 ◽

2015 ◽

Vol 63 (2) ◽

pp. 477-490 ◽

Cited By ~ 7

Author(s):

John R. Teasdale ◽

Steven B. Mirsky

Keyword(s):

Cover Crop ◽

Dominant Species ◽

Management Practices ◽

Crop Management ◽

Planting Date ◽

Hairy Vetch ◽

Planting Dates ◽

Weed Biomass ◽

Giant Foxtail ◽

Smooth Pigweed

Insufficient weed control is a major constraint to adoption of reduced-tillage practices for organic grain production. Tillage, cover crop management, and crop planting date are factors that influence emergence periodicity and growth potential of important weed species in these systems. We assessed two hairy vetch cover crop management practices, disk-kill and roll-kill, across a range of corn planting dates from early May to late June in three experiments in Beltsville, MD. Patterns of seed dormancy, emergence, and early weed growth were determined for overseeded populations of common ragweed, giant foxtail, and smooth pigweed, three important species in the Mid-Atlantic states that represent early to late emergence. Common ragweed emergence was lowest and dormancy was highest of the three species across all planting dates. Giant foxtail emergence was higher than the other species in roll-killed hairy vetch and included a significant number of seeds that germinated before rolling operations in late June. Smooth pigweed had the highest emergence and lowest dormancy in disk-killed hairy vetch in June. Individual giant foxtail plant weight was higher in roll-killed than disk-killed hairy vetch in 2 of 3 yr, whereas that of smooth pigweed plants was higher in disk-killed than roll-killed vetch in 2 of 3 yr. Giant foxtail was the dominant species in roll-killed hairy vetch (averaged 79% of total weed biomass at corn silking), probably because of early germination and establishment before rolling operations. Smooth pigweed was the dominant species in disk-killed hairy vetch at June planting dates (averaged 77% of total weed biomass), probably because of high growth rates under warm conditions in tilled soil. This research demonstrated that cover crop management practices and the timing of planting operations can shift the dominant species of weed communities in organic farming systems and must be considered in long-term weed management planning.

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ROTATION IN CONSERVATION AGRICULTURE SYSTEMS OF ZAMBIA: EFFECTS ON SOIL QUALITY AND WATER RELATIONS

Experimental Agriculture ◽

10.1017/s001447971000030x ◽

2010 ◽

Vol 46 (3) ◽

pp. 309-325 ◽

Cited By ~ 88

Author(s):

C. THIERFELDER ◽

P. C. WALL

Keyword(s):

Soil Moisture ◽

Soil Quality ◽

Cover Crop ◽

Green Manure ◽

Conservation Agriculture ◽

Crop Rotations ◽

Water Infiltration ◽

Total Carbon ◽

Control Treatment ◽

Positive Effects

SUMMARYConservation agriculture (CA) systems are based on minimal soil disturbance, crop residue retention and crop rotation. Although the capacity of rotations to break pest and disease cycles is generally recognized, other benefits of crop rotations in CA systems are seldom acknowledged and little understood. We monitored different conventional and CA cropping systems over the period from 2005 to 2009 in a multi-seasonal trial in Monze, southern Zambia. Both monocropped maize and different maize rotations including cotton and the green manure cover crop sunnhemp (Crotalaria juncea) were compared under CA conditions, with the aim of elucidating the effects of crop rotations on soil quality, soil moisture relations and maize productivity. Infiltration, a sensitive indicator of soil quality, was significantly lower on conventionally ploughed plots in all cropping seasons compared to CA plots. Higher water infiltration rate led to greater soil moisture content in CA maize treatments seeded after cotton. Earthworm populations, total carbon and aggregate stability were also significantly higher on CA plots. Improvements in soil quality resulted in higher rainfall use efficiency and higher maize grain yield on CA plots especially those in a two- or three-year rotation. In the 2007/08 and 2008/2009 season, highest yields were obtained from direct-seeded maize after sunnhemp, which yielded 74% and 136% more than maize in the conventionally ploughed control treatment with a continuous maize crop. Even in a two-year rotation (maize-cotton), without a legume green manure cover crop, 47% and 38% higher maize yields were recorded compared to maize in the conventionally ploughed control in the two years, respectively. This suggests that there are positive effects from crop rotations even in the absence of disease and pest problems. The overall profitability of each system will, however, depend on markets and prices, which will guide the farmer's decision on which, if any, rotation to choose.

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Crop planting date matters: Estimation methods and effect on future yields

Agricultural and Forest Meteorology ◽

10.1016/j.agrformet.2016.03.023 ◽

2016 ◽

Vol 223 ◽

pp. 103-115 ◽

Cited By ~ 29

Author(s):

Laura Dobor ◽

Zoltán Barcza ◽

Tomáš Hlásny ◽

Tamás Árendás ◽

Tamás Spitkó ◽

...

Keyword(s):

Planting Date ◽

Estimation Methods ◽

Crop Planting

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Spatial and temporal variability in Powell amaranth (Amaranthus powellii) emergence under strip tillage with cover crop residue

Weed Science ◽

10.1614/ws-d-16-00082.1 ◽

2016 ◽

Vol 65 (1) ◽

pp. 151-163 ◽

Cited By ~ 5

Author(s):

Erin R. Haramoto ◽

Daniel C. Brainard

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Crop Residue ◽

Field Experiments ◽

Abiotic Factors ◽

Planting Date ◽

Spatial And Temporal Variability ◽

Natural Rainfall ◽

Strip Tillage ◽

The Impact

The objectives of this research were to evaluate temporal and spatial variability in the impact of strip tillage and oat cover crop residue on Powell amaranth emergence and to determine the role of rainfall in mediating these effects. In field experiments conducted in 2010, 2011, and 2012, Powell amaranth seeds were sown in a fully factorial combination of two tillage types (strip tillage [ST] vs. full-width tillage [FWT]) and cover crop residue (oats vs. none) at either 0 d after tillage (DAT) or 7 to 13 DAT to monitor emergence at two timings. In ST plots, seeds were sown both in the tilled zone (“in-row,” IR), and between these tilled zones (“between-row,” BR). In 2011 and 2012, three levels of rainfall were simulated in subplots by either excluding rainfall, allowing natural rainfall, or supplementing rainfall with irrigation. In most cases, ST and oats residue either had no effect on or suppressed emergence of Powell amaranth sown at the early planting date. In contrast, the emergence response to ST and residue at the later planting date was generally smaller and more variable, with increases in emergence observed in several cases. Differences between tillage systems in emergence were most pronounced in the BR zone but also occurred IR in some cases, suggesting that interzonal effects on biotic or abiotic factors influenced emergence. Oat residue effects—but rarely tillage effects—were often mediated by simulated rainfall, with increases in emergence occurring mostly in dry conditions and decreases occurring more commonly in wetter conditions. These results demonstrate that the suppressive effects of cover crops and ST on weed emergence are inconsistent, temporally and spatially variable, and dependent on complex interactions with factors including rainfall.

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Effectiveness of Cover Crop Termination Methods on No-Till Cantaloupe

Agriculture ◽

10.3390/agriculture12010066 ◽

2022 ◽

Vol 12 (1) ◽

pp. 66

Author(s):

Ted S. Kornecki ◽

Corey M. Kichler

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Hairy Vetch ◽

Two Stage ◽

Cereal Rye ◽

Crimson Clover ◽

Termination Rate ◽

Growing Seasons ◽

No Till ◽

Crop Planting

In a no-till system, there are many different methods available for terminating cover crops. Mechanical termination, utilizing rolling and crimping technology, is one method that injures the plant without cutting the stems. Another popular and commercially available method is mowing, but this can cause problems with cover crop re-growth and loose residue interfering with the planter during cash crop planting. A field experiment was conducted over three growing seasons in northern Alabama to determine the effects of different cover crops and termination methods on cantaloupe yield in a no-till system. Crimson clover, cereal rye, and hairy vetch cover crops were terminated using two different roller-crimpers, including a two-stage roller-crimper for four-wheel tractors and a powered roller-crimper for a two-wheel walk-behind tractor. Cover crop termination rates were evaluated one, two, and three weeks after termination. Three weeks after rolling, a higher termination rate was found for flail mowing (92%) compared to lower termination rates for a two-stage roller (86%) and powered roller-crimper (85%), while the control termination rate was only 49%. There were no significant differences in cantaloupe yield among the rolling treatments, which averaged 38,666 kg ha−1. However, yields were higher for cereal rye and hairy vetch cover crops (41,785 kg ha−1 and 42,000 kg ha−1) compared to crimson clover (32,213 kg ha−1).

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Conservation Tillage of Sweetpotato

HortScience ◽

10.21273/hortsci.32.4.605f ◽

1997 ◽

Vol 32 (4) ◽

pp. 605F-606

Author(s):

Lewis W. Jett ◽

Timothy P. Talbot

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Ipomoea Batatas ◽

Conservation Tillage ◽

Cultural Practice ◽

Planting Date ◽

White Grub ◽

Storage Roots ◽

Marketable Yield ◽

Crop Species

A cultural practice that can modify and conserve the soil environment is needed in sweetpotato [Ipomoea batatas (L.) Lam.] production. The objective of this research was to evaluate conventional and conservation tillage of sweetpotato with four cover crop species (fallow, ryegrass, rye, and wheat). The cover crops were seeded in late Oct. 1995, and the sweetpotato transplants (`Beauregard') were transplanted at two dates the following spring (May and June). Conservation tillage significantly lowered soil temperature (10 cm depth) during storage root initiation and development. Moreover, each cover crop significantly reduced weed emergence and soil erosion. The ryegrass conservation tillage treatment significantly increased marketable yield of sweetpotato in the first planting date, while rye and wheat performed equally well in the second planting date. In the second planting date, white grub (Phyllophaga ephilida Say) injury to storage roots was significantly higher in the conservation tillage treatments. However, conservation tillage seems to be a viable alternative to the conventional method of sweetpotato production.

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