Role of Annual Legume Cover Crops in Efficient Use of Water and Nitrogen

Long-term carbon (C) stabilisation in tropical and subtropical soils under no-tillage (NT) rests on the formation of mineral–organic associations (MOAs) that can be enriched with microbial metabolites. In this work, we assessed the role of long-term tillage and cropping systems and mineral N fertilisation in enriching MOAs with microbial metabolites in a subtropical soil. For this purpose, we sampled a sandy clay loam Acrisol up to 1 m depth involved in an ongoing 30-year-old experiment under two different tillage systems (conventional tillage and NT) in the presence and absence of legume cover crops and mineral nitrogen (N) fertilisation. The soil samples were subjected to particle size fractionation and n-alkane analysis. The NT and the presence of legume cover crops in the surface soil layer (0−5 cm) increased the abundance of plant-derived lipids (i.e. compounds with n-alkane chains of 25−33 C atoms) in the whole soil. Microbial-derived lipids (i.e. compounds with shorter n-alkane chains (15−24 C atoms)) were more abundant in the clay fraction of the surface (0−5 cm) and sub-surface soil layers (20−30 and 75−100 cm) in NT soil receiving high-quality residues of legume cover crops. However, N fertilisation decreased the abundance of microbial-derived lipids in the clay fraction of the 0−5 and 20−30 cm soil layers. Our findings highlight the role of N-rich residues of legume cover crops, but not of mineral N fertilisation, in the long-term stabilisation of C in MOAs in NT soils through the action of microbial residues.

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Legume Cover Crops as a Nitrogen Source for No‐Till Corn and Grain Sorghum

Agronomy Journal ◽

10.2134/agronj1990.00021962008200040023x ◽

1990 ◽

Vol 82 (4) ◽

pp. 769-772 ◽

Cited By ~ 88

Author(s):

R. L. Blevins ◽

J. H. Herbek ◽

W. W. Frye

Keyword(s):

Nitrogen Source ◽

Cover Crops ◽

Grain Sorghum ◽

No Till ◽

Legume Cover Crops

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Legume Cover Crops with Winter Cereals in Southern Manitoba

Agronomy Journal ◽

10.2134/agronj2001.9351086x ◽

2001 ◽

Vol 93 (5) ◽

pp. 1086-1096 ◽

Cited By ~ 38

Author(s):

Joanne R. Thiessen Martens ◽

Jeff W. Hoeppner ◽

Martin H. Entz

Keyword(s):

Cover Crops ◽

Winter Cereals ◽

Legume Cover Crops

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Influence of legume cover crops and conservation tillage on soil populations of selected fungal genera

Canadian Journal of Microbiology ◽

10.1139/m88-038 ◽

1988 ◽

Vol 34 (3) ◽

pp. 201-206 ◽

Cited By ~ 9

Author(s):

C. S. Rothrock ◽

W. L. Hargrove

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Conservation Tillage ◽

Field Studies ◽

Macrophomina Phaseolina ◽

Hairy Vetch ◽

Fusarium Spp ◽

Crimson Clover ◽

Legume Cover Crops ◽

Legume Cover Crop

The influence of winter legume cover crops and of tillage on soil populations of fungal genera containing plant pathogenic species in the subsequent summer sorghum crop were examined in field studies. Legume cover crops significantly increased populations of Pythium spp. throughout the sorghum crop compared with a rye cover crop or no cover crop. This stimulation of the populations of Pythium spp. was not solely due to colonization of cover-crop residue, as populations were significantly greater at the time the legume cover crop was desiccated. Removal of aboveground residue generally decreased populations of Pythium spp. in soil. Incorporation of residue by tillage increased populations of Pythium spp. at some sampling dates. Legumes differed in the magnitude of stimulation, with hairy vetch stimulating Pythium spp. more than crimson clover. Cover crop treatments did not consistently influence soil populations of Fusarium spp., Rhizoctonia solani, Rhizoctonia-like binucleate fungi, or Macrophomina phaseolina. Macrophomina phaseolina populations were significantly greater under no tillage.

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Enzymatic activity and mineralization of carbon and nitrogen in soil cultivated with coffee and green manures

Revista Brasileira de Ciência do Solo ◽

10.1590/s0100-06832010000500010 ◽

2010 ◽

Vol 34 (5) ◽

pp. 1573-1583 ◽

Cited By ~ 17

Author(s):

Elcio Liborio Balota ◽

Julio César Dias Chaves

Keyword(s):

Enzyme Activity ◽

Cover Crops ◽

Leucaena Leucocephala ◽

N Mineralization ◽

Urease Activity ◽

Tree Canopy ◽

C And N Mineralization ◽

Legume Cover Crops ◽

C And N ◽

Coffee Plants

There are great concerns about degradation of agricultural soils. It has been suggested that cultivating different plant species intercropped with coffee plants can increase microbial diversity and enhance soil sustainability. The objective of this study was to evaluate enzyme activity (urease, arylsulfatase and phosphatase) and alterations in C and N mineralization rates as related to different legume cover crops planted between rows of coffee plants. Soil samples were collected in a field experiment conducted for 10 years in a sandy soil in the North of Paraná State, Brazil. Samples were collected from the 0-10 cm layer, both from under the tree canopy and in-between rows in the following treatments: control, Leucaena leucocephala, Crotalaria spectabilis, Crotalaria breviflora, Mucuna pruriens, Mucuna deeringiana, Arachis hypogaea and Vigna unguiculata. The soil was sampled in four stages of legume cover crops: pre-planting (September), after planting (November), flowering stage (February) and after plant residue incorporation (April), from 1997 to 1999. The green manure species influenced soil enzyme activity (urease, arylsulfatase and phosphatase) and C and N mineralization rates, both under the tree canopy and in-between rows. Cultivation of Leucaena leucocephala increased acid phosphatase and arilsulfatase activity and C and N mineralization both under the tree canopy and in-between rows. Intercropped L. leucocephala increased urease activity under the tree canopy while C. breviflora increased urease activity in-between rows.

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Evaluation of Chemical Termination Options for Cover Crops

Weed Technology ◽

10.1017/wet.2017.113 ◽

2018 ◽

Vol 32 (3) ◽

pp. 227-235 ◽

Cited By ~ 7

Author(s):

Matheus G. Palhano ◽

Jason K. Norsworthy ◽

Tom Barber

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Agricultural Research ◽

Yield Potential ◽

Crop Acreage ◽

Potential Cost ◽

Cereal Rye ◽

Crimson Clover ◽

Legume Cover Crops ◽

And Control

AbstractCover crop acreage has substantially increased over the last few years due to the intent of growers to capitalize on federal conservation payments and incorporate sustainable practices into agricultural systems. Despite all the known benefits, widespread adoption of cover crops still remains limited due to potential cost and management requirements. Cover crop termination is crucial, because a poorly controlled cover crop can become a weed and lessen the yield potential of the current cash crop. A field study was conducted in fall 2015 and 2016 at the Arkansas Agricultural Research and Extension Center in Fayetteville to evaluate preplant herbicide options for terminating cover crops. Glyphosate-containing treatments controlled 97% to 100% of cereal rye and wheat, but glyphosate alone controlled less than 57% of legume cover crops. The most effective way to control hairy vetch, Austrian winterpea, and crimson clover with glyphosate resulted from mixtures of glyphosate with glufosinate, 2,4-D, and dicamba. Higher rates of auxin herbicides improved control in these mixtures. Glufosinate alone or in mixture controlled legume cover crops 81% or more. Paraquat plus metribuzin was effective in terminating both cereal and legume cover crops, with control of cereal cover crops ranging from 87% to 97% and control of legumes ranging from 90% to 96%. None of these herbicides or mixtures adequately controlled rapeseed.

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The role of cover crops in irrigated systems: Soil salinity and salt leaching

Agriculture Ecosystems & Environment ◽

10.1016/j.agee.2012.06.012 ◽

2012 ◽

Vol 158 ◽

pp. 200-207 ◽

Cited By ~ 26

Author(s):

J.L. Gabriel ◽

P. Almendros ◽

C. Hontoria ◽

M. Quemada

Keyword(s):

Soil Salinity ◽

Cover Crops ◽

Salt Leaching

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Biomass Production and Potential Fixed Nitrogen Inputs from Leguminous Cover Crops in Subtropical Avocado Plantations

Agronomy ◽

10.3390/agronomy9020070 ◽

2019 ◽

Vol 9 (2) ◽

pp. 70

Author(s):

Terry J. Rose ◽

Lee J. Kearney

Keyword(s):

Biomass Production ◽

White Clover ◽

Cover Crops ◽

Persea Americana ◽

N Fixation ◽

N Losses ◽

N Accumulation ◽

Tree Crop ◽

Nitrogen Inputs ◽

Legume Cover Crops

Nitrogen (N) fertiliser is applied to perennial horticultural crops to increase yields, but subsequent N losses in subtropical plantations may be high due to intense rainfall and warmer temperatures. While legume cover crops could potentially contribute N to the tree crops and reduce fertiliser-N requirements, few studies have quantified potential fixed-N inputs from cover crops legumes in tropical or subtropical tree crop systems. To address this, we investigated growth and N fixation of summer-growing Pinto peanut (Arachis pintoi Krapov. & W. C. Greg cv. Amarillo) and winter/spring dominant white clover (Trifolium repens L. cv. Haifa) grown as a mixed species cover crop in two commercial subtropical avocado (Persea americana Mill. cv. Hass) plantations. Legume biomass was assessed prior to mowing of the inter-row (fortnightly in summer and every 6–8 weeks over winter) and N fixation was estimated using the 15N natural abundance technique. Biomass production was 7377 kg ha−1 (930 kg ha−1 for white clover and 6447 kg ha−1 for Pinto peanut) at the first site over the 14-month period from December 2014 to January 2016, and 4467 kg ha−1 (1114 kg ha−1 for white clover and 3353 kg ha−1 for Pinto peanut) at the second site over the same period. Estimation of N fixation was not possible at the first site, due to a lack of difference in isotopic discrimination between the legume shoots and the reference plant (kikuyu (Pennisetum clandestinum Chiov.)) material. While legume shoots accumulated 157 kg N ha−1 (38 kg ha−1 for white clover and 119 kg ha−1 for Pinto peanut) across the season at site 1, the % N derived from atmosphere (%Ndfa) in legumes was relatively low (50–60% in Pinto peanut during the warmer months and around 30% in autumn and early spring, and from 13 % in April to 69% in September for white clover). The low %Ndfa in the legumes may have been due to low rainfall or molybdenum (Mo) deficiency. Ultimately the legume cover crops contributed an estimated 50 kg fixed N ha−1, which could partially offset fertiliser N requirements of the tree crop. Our results demonstrate the need to quantify N fixation in legume cover crops to assess potential N benefits as opposed to relying on typical measurements of legume biomass and N accumulation.

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