Cover Crop Management in a Sauvignon Blanc/Ramsey Vineyard in the Semi-Arid Olifants River Valley, South Africa. 3. Effect of Different Cover Crops and Cover Crop Management Practices on the Organic Matter and Macro-Nutrient Contents of a Sandy Soil

Economic analysis compared the returns of cropping systems and management practices for production of fall lettuce (Lactuca sativa L.) and spring cantaloupe (Cucumis melo) following summer cover crops. The cover crop treatments included: cowpea [Vigna unguiculata (L.) Walp.] incorporated into the soil in the fall, cowpea used as mulch in the fall, sorghum sudangrass [Sorghum bicolor (L.) Moench] incorporated into the soil in the fall, and a bare ground control. Lettuce and cantaloupe were managed using conventional, integrated, and organic practices. The effect of each cropping system and management practice on crop yield, cost of production and net return was determined. In 1999 and 2000, yield and net return were greatest for cantaloupe and lettuce when the cowpea cover crop was incorporated into the soil before planting. The effect of crop management practice varied with type of cover crop. When lettuce was planted into cowpea-incorporated treatment in 1999, conventional management had the highest cash return followed by integrated crop management. In 2000, organically-grown lettuce after cowpea incorporated had the highest net return followed by integrated crop management grown under cowpea incorporated treatments. In 1999 and 2000, integrated cantaloupe following cowpea-incorporated treatment had the highest yield and cash-return. A 20% price premium for organic produce increased the net returns for the organic-grown lettuce and cantaloupe. Organic lettuce following cowpea-incorporated treatments produced a high net of $2,516/ha in 1999 and $5,971/ha in 2000. The net returns due to 20% organic premium price varied between 1999 and 2000 in cantaloupe production. They were highest for organic cantaloupe after bareground with a net return of $4,395 in 1999 and $3,148 in 2000 for organic cantaloupe after sudangrass.

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Response of soil organic matter indices and fractions after 37 years of wheat production management practices in semi-arid South Africa

South African Journal of Plant and Soil ◽

10.1080/02571862.2019.1698777 ◽

2020 ◽

Vol 37 (2) ◽

pp. 136-143

Author(s):

T Motema ◽

E Kotzé ◽

PF Loke ◽

CC du Preez

Keyword(s):

South Africa ◽

Organic Matter ◽

Soil Organic Matter ◽

Production Management ◽

Management Practices ◽

Wheat Production ◽

Semi Arid

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Organic Farming and Cover-Crop Management Reduce Pest Predation in Austrian Vineyards

Insects ◽

10.3390/insects12030220 ◽

2021 ◽

Vol 12 (3) ◽

pp. 220

Author(s):

Jo Marie Reiff ◽

Sebastian Kolb ◽

Martin H. Entling ◽

Thomas Herndl ◽

Stefan Möth ◽

...

Keyword(s):

Organic Farming ◽

Pest Control ◽

Cover Crops ◽

Cover Crop ◽

Management Practices ◽

Integrated Management ◽

Lobesia Botrana ◽

Management Options ◽

Natural Pest Control ◽

Predation Rates

Habitat simplification and intensive use of pesticides are main drivers of global arthropod declines and are, thus, decreasing natural pest control. Organic farming, complex landscapes, and local vineyard management practices such as implementation of flower-rich cover-crop mixtures may be a promising approach to enhance predator abundance and, therefore, natural pest control. We examined the effect of organic versus integrated management, cover-crop diversity in the vineyard inter-rows, and landscape composition on the natural pest control of Lobesia botrana eggs and pupae. Predation of L. botrana pupae was reduced by organic farming and species-poor cover-crops by about 10%. Predation rates of L. botrana eggs did not differ significantly in any of the studied management options. Dominant predators were earwigs (Forficulidae), bush crickets (Tettigoniidae), and ants (Formicidae). Negative effects of organic viticulture are most likely related to the negative nontarget effects on arthropods related to the frequent sulfur and copper applications in combination with the avoidance of strongly damaging insecticides by integrated winegrowers. While a 10% difference in predation rates on a single pest stage is unlikely to have strong practical implications, our results show that the assumed effectiveness of environmentally friendly agriculture needs to be evaluated for specific crops and regions.

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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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