Effect of Cover Crops Associated With Lettuce Production Under No-Tillage System

The use of cover crops has benefits for the chemical, physical and biological properties of the soil. However, together with the need for good vegetable productivity, considerable challenges arise in several regions of Brazil. The preparation of conventional soil for initiating no-tillage systems is necessary to create a management history and assimilate the benefits of the no-tillage system in vegetables, ensuring sustainable production. The objective of this research was to evaluate lettuce yield as a function of different cover crops as a function of resistance to soil penetration. The experiment was conducted in the horticulture sector of the University of Rio Verde, Rio Verde, Goiás, Brazil. The cover crops used were sunflower (Helianthus annuus), sunn hemp (Crotalaria juncea), and fallow, and the vegetable used was lettuce (Lactuca sativa). The variables analyzed were plant height and lettuce yield, straw decomposition, and soil resistance to penetration. The collected data were submitted to analysis of variance, and if significant, was compared by Tukey test (p < 0.05) and regression analysis. The lettuce height in the different management systems showed no statistical differences. The decomposition of the straw presented accentuated degradation for the evaluated cover crops and the productivity was bigger in the straw of crotalaria and fallow. Soil resistance for cover crops was not greater than 2 MPa.

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Agronomic performance of cover crops and upland rice cultivars grown in sucession with different nitrogen rates in no-tillage system

Cultura Agronômica: Revista de Ciências Agronômicas ◽

10.32929/2446-8355.2018v27n2p173-189 ◽

2018 ◽

Vol 27 (2) ◽

pp. 173-189

Author(s):

Geovane Lima Guimarães ◽

Salatiér Buzetti ◽

Edson Cabral Da Silva ◽

Orivaldo Arf ◽

Marco Eustáquio De Sá ◽

...

Keyword(s):

Grain Yield ◽

Cover Crops ◽

Upland Rice ◽

No Tillage ◽

Rice Cultivars ◽

Positive Effects ◽

Sunn Hemp ◽

Tillage System ◽

World Food Security ◽

N Rates

Rice is considered by FAO as one of the most important foods to world food security and nitrogen (N) is the nutrient that most often affects the productivity of this crop, with its dynamics in the soil-plant system changed by management used. With the objective of evaluating the yield and quantities of nutrients in the phytomass of cover crops; and to evaluate the influence of the isolated and combined use of cover crops and urea as N sources on the growth, productivity and grain quality of upland rice cultivars irrigated, in the implantation of the no-tillage system, was carried out a study in an Oxisol (Rhodic Haplustox), cerrado (savannah) phase at the Experimental Farm of UNESP/FEIS, in Selvíria-MS, Brazil. The experimental design was in randomized blocks, with four repetitions, in a 4x2x3 factorial scheme. The treatments were a combination of four cover crops: velvet bean (Mucuna aterrima), sunn hemp (Crotalaria juncea), millet (Pennisetum glaucum) and spontaneous vegetation (fallow in off-season); and two rice cultivars: Primavera and IAC 202; and three N rates: 0, 50 and 100 kg ha-1 as urea. The millet, followed by sunn hemp, produced the highest yield of dry phytomass and accumulation of nutrients. The succession sunn hemp-rice promoted higher grain yield, regardless of the N rate applied, while the cultivar IAC 202 was the most productive than Primavera. The increase of the N rate caused a drop in the number of spikelets seedless per panicle, with positive effects on grain yield. These results contribute with information about the cover plants and more efficient N rates to increase the quality and yield of rice crop.

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Green and sweet corn grown under different cover crops and phases of the no-tillage system

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v26n3p173-179 ◽

2022 ◽

Vol 26 (3) ◽

pp. 173-179

Author(s):

Diemisson O. Nunes ◽

João H. de S. Favaro ◽

Hamilton C. de O. Charlo ◽

Arcângelo Loss ◽

Antônio C. Barreto ◽

...

Keyword(s):

Cover Crops ◽

Dry Matter ◽

Sweet Corn ◽

Block Design ◽

Dry Mass ◽

Agronomic Performance ◽

No Tillage ◽

Randomized Block Design ◽

Sunn Hemp ◽

Tillage System

ABSTRACT Special corn is cultivated all year conventionally round; however, its productivity increases when grown under a no-tillage system (NTS). This study aimed to evaluate the agronomic performance of sweet and green corn cultivated under residues of different cover crops and the NTS implantation stages. Two experiments were carried out in the randomized block design, with four replications, in each of the three areas. The experiments consisted of evaluating the sweet and green corn, simultaneously, in three areas at different stages of development of NTS: initial (1 year), transition (7 years), and consolidation (19 years) with six types of cover crops: Signal grass (SG), Pearl millet (PM), Sunn hemp (SH), a mixture of SG + SH, SG + PM, and PM + SH. The dry matter (DM) production of the cover crops, the productivity of husked and unhusked ears, straw, and grain yield were evaluated. The SH had the highest dry mass production among the studied cover crops in all phases of the NTS. The phase of the NTS did not influence the productivity of ears with or without husk in green corn. The cultivation of sweet corn in transition and consolidation areas of the NTS showed better yields when compared to the initial phase of the system.

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Soil organic matter of aggregates physicogenic and biogenic in areas under no-tillage system in the Cerrado, Brazil

Research Society and Development ◽

10.33448/rsd-v10i5.15012 ◽

2021 ◽

Vol 10 (5) ◽

pp. e39910515012

Author(s):

Luiz Alberto da Silva Rodrigues Pinto ◽

Melania Merlo Ziviani ◽

Igor de Sousa Morais ◽

Robert Ferreira ◽

Wanderson Farias da Silva Junior ◽

...

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Organic Carbon ◽

Cover Crops ◽

No Tillage ◽

Aggregate Formation ◽

Density Fractionation ◽

Sampling Area ◽

Sunn Hemp ◽

Tillage System

The aim of this study was to evaluate i) the different cover crops contribution used in no-tillage system (NT) to biogenic aggregation; and ii) the influence of aggregate formation pathways on the compartmentalization and the soil organic carbon origin. Two areas managed under NT with different implementation times (6 and 18 years, NT06 and NT18, respectively) and cover crops were evaluated, totaling six sampling areas: NT06, millet (NT06MI); NT06, brachiaria (NT06BR); NT06, sunn hemp (NT06SH); NT18, millet (NT18MI); NT18, brachiaria (NT18BR); NT18, and sunn hemp (NT18SH). In each sampling area, five pseudo-replicates were collected in the 0.00-0.05 and 0.05-0.10 m layers. The samples were air-dried and sieved using sieves with 9.7 and 8.0 mm mesh, and the aggregates retained within this interval were selected. The percentage of each type of aggregate (physicogenic and biogenic) was quantified. Total organic carbon (TOC) and the natural abundance of δ13C (‰) were analyzed and the physical fractionations of SOM were performed: particulate organic carbon (POC) and mineral-associated organic carbon (MAOC) and density fractionation (free light fraction carbon, FLFC). Physicogenic aggregates were quantified in greater proportion, except for the areas of NT06BR and NT18BR in the 0.00-0.05 m layer. The biogenic aggregates showed the highest contents of TOC, POC, MAOC, FLFC and more negative values of δ13C. The use of grasses, especially Brachiaria spp., as cover plants in NT after 6 and 18 years of adoption favors the formation of aggregates through the biogenic pathway and they influence the compartmentalization and origin of stored organic carbon.

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Diversity and Longevity of the Soybean Debris Mycobiota in a No-Tillage System

Plant Disease ◽

10.1094/pdis.1997.81.5.530 ◽

1997 ◽

Vol 81 (5) ◽

pp. 530-534 ◽

Cited By ~ 25

Author(s):

R. E. Baird ◽

B. G. Mullinix ◽

A. B. Peery ◽

M. L. Lang

Keyword(s):

Cover Crops ◽

Survival Rates ◽

Fungal Species ◽

No Tillage ◽

Cercospora Kikuchii ◽

Tillage System ◽

Mesh Bags ◽

Colletotrichum Spp ◽

The Mean ◽

Total Fungi

The survival of the mycobiota on pod and stem debris of soybean produced in a no-tillage system with cover crops of alfalfa, canola, rye, or wheat or with no cover was studied during 1994 and 1995. Fiberglass mesh bags containing pods and stems were assayed every 28 to 31 days to determine the isolation frequency of fungi. Over 90% of the 11,906 isolates obtained were members of the Deuteromycotina. The most common genera isolated were Alternaria, Cercos-pora, Colletotrichum, Epicoccum, Fusarium, and Phoma. Alternaria spp. had the greatest isolation frequencies and constituted 40% of the total cultures. Numbers of total fungi (all fungi isolated) on sampling dates in 1994 were similar to the totals in 1995. In May 1994, the mean isolation rates for many of the fungal species were significantly lower (P = 0.05) in several of the cover crops, but no consistent pattern could be determined. Common soybean pathogens isolated included Colletotrichum spp., Diaporthe spp., and Cercospora kikuchii. Fusarium graminearum, which is responsible for several diseases of maize and wheat, was commonly isolated during this study. Of the Diaporthe spp. (anamorph Phomopsis spp.), 87% were identified as D. phaseolorum var. sojae. Colletotrichum spp. were identified as C. truncatum in 85% of the isolates, C. destructivum (teleomorph Glomerella glycines) in 12%, and both species in 3%. Cercospora kikuchii was more commonly isolated from pods than from stem tissue, and Colletotrichum spp. occurred more frequently on stems. Isolation frequencies of Diaporthe spp. were greater in May of both years than in the preceding months. These results show that no-tillage soybean debris harbors numerous fungi pathogenic to soybean, and producers who grow soybeans continuously may find more disease in this crop and lower yields. Fungi that attack crops such as maize and wheat were commonly isolated from soybean debris in both years, and a no-tillage rotation which includes maize or wheat could result in increased disease in these crops. Isolation frequencies of the fungi from cover crops varied with the sampling date, but no consistent patterns could be determined for a particular cover crop or fungal species. This is the first detailed study of survival rates of soybean, maize, and wheat pathogens that overwinter on soybean debris in a no-tillage system.

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Nitrogen fertilization of vegetables cultivated under no-tillage after cover crops

Horticultura Brasileira ◽

10.1590/s0102-053620170116 ◽

2017 ◽

Vol 35 (1) ◽

pp. 103-110 ◽

Cited By ~ 2

Author(s):

Roberto BF Branco ◽

Sally F Blat ◽

Tais GS Gimenes ◽

Rodrigo HD Nowaki ◽

Humberto S Araújo ◽

...

Keyword(s):

Plant Growth ◽

Cover Crops ◽

Nitrogen Fertilization ◽

Nitrate Concentration ◽

Dry Mass ◽

Growth And Yield ◽

No Tillage ◽

Biological Fixation ◽

Sunn Hemp ◽

Nitrogen Rates

ABSTRACT The production of horticultural crops in no-tillage and in rotation with cover crops reduces the dependency in nitrogen fertilizer, due to increased soil organic matter and by biological fixation performed by legumes. Thus, the aim of this work was to study rates of nitrogen fertilization and cover crops in the agronomic performance of tomato and broccoli grown under no-tillage. The experiment was conducted in a split plot design with four replications. Treatments consisted of cover crops, sunn hemp and millet, and four rates of nitrogen fertilization (0, 50, 100 and 200 kg/ha of nitrogen), for both the tomato and broccoli crops. All soil management was performed in no-tillage. For tomato crops we evaluated the plant growth, the nitrate concentration of sprouts and fruits and yield of commercial and non commercial fruits. For broccoli we evaluated plant growth and yield. There was an interaction effect between cover crop and nitrogen rates to tomato growth measured at 100 days after transplanting, for plant height, number of fruit bunches, dry mass of leaves and diameter of the stalk. The tomato commercial fruit number and yield showed maximum values with 137 and 134 kg/ha of N respectively, on the sunn hemp straw. The nitrate concentration of the tomato sprouts was linearly increasing with the increase of nitrogen rates, when grown on the millet straw. For broccoli production, the maximum fresh mass of commercial inflorescence was with 96 kg/ha of N, when grown on the millet straw.

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Strategies to terminate summer cover crops for weed management in no-tillage vegetable production in southeast Brazil

Weed Science ◽

10.1017/wsc.2021.58 ◽

2021 ◽

pp. 1-26

Author(s):

Roberto Botelho Ferraz Branco ◽

Fernando de Carvalho ◽

João Paulo de Oliveira ◽

Pedro Luis da Costa Alves

Keyword(s):

Pearl Millet ◽

Cover Crops ◽

Weed Management ◽

Cover Crop ◽

Weed Suppression ◽

No Tillage ◽

Weed Biomass ◽

Jack Bean ◽

Organic Mulch ◽

Sunn Hemp

Abstract Cover crop residue left on the soil surface as organic mulch in no-tillage crop production provides several environmental benefits, including weed suppression. Thus, many farmers who use cover crops attempt to reduce the use of agricultural inputs, especially herbicides. Therefore, our objectives were to study the potential of different cover crop species to suppress weeds and produce an in situ organic mulch, and evaluate the effect of the organic mulch with and without spraying glyphosate on weed suppression for vegetable (tomato (Solanum lycopersicum L. and broccoli (Brassica oleracea L. var. botrytis) growth and yield. Five cover crop treatments (sunn hemp (Crotalaria juncea L.), jack bean [Canavalia ensiformis (L.) DC.], pearl millet [Pennisetum glaucum (L.) R. Br.], grain sorghum [Sorghum bicolor (L.) Moench ssp. bicolor] and a no-cover crop (control)) were used in the main plots; and spraying or no spraying glyphosate on the flattened cover crop in the sub plots of split-plot experimental design. Organic mulch from pearl millet, sorghum and sunn hemp resulted in lower weed biomass during the early season of both tomato and broccoli than jack bean and no-cover crop (control). Spraying glyphosate after roller crimping reduced weed biomass by 103 g m−2 and 20 g m−2 by 45 and 60 days after transplanting (DAT) of tomato, respectively and resulted in a better tomato yield compared to non spraying. Glyphosate reduced weed biomass by 110 g m−2 in the early season of broccoli (30 DAT), but did not affect yield. Terminating high biomass cover crops with a roller crimper is a promising technique for weed management in vegetable crops, which has the potential to reduce or even eliminate the need for herbicide.

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