Microbial biomass and mineral N transformations in soil planted with barley, ryegrass, pea or turnip

Wheatley, Ron E.; Ritz, Karl; Griffiths, Bryan S.

doi:10.1007/bf00014422

Cited by 74 publications

(44 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A high C:N ratio stimulates the microbial community to degrade organic substrate thereby increasing determined microbial population. C:N ratio is higher in cereals straw substrates [20,21], which provides more substrate to microorganisms explaining the highest SDI found in this work on plots where uniquely cereals (oat and maize) were grown throughout the year. Besides crops and C:N ratio, root exudates are also key factors that influence microbial communities, as they provide a carbon source to soil microorganisms [22,23].…”

Section: Discussionmentioning

confidence: 55%

The Effect of Tillage System and Crop Rotation on Soil Microbial Diversity and Composition in a Subtropical Acrisol

et al. 2012

View full text Add to dashboard Cite

Agricultural management alters physical and chemical soil properties, which directly affects microbial life strategies and community composition. The microbial community drives important nutrient cycling processes that can influence soil quality, cropping productivity and environmental sustainability. In this research, a long-term agricultural experiment in a subtropical Acrisol was studied in south Brazil. The plots at this site represent two tillage systems, two nitrogen fertilization regimes and three crop rotation systems. Using Illumina high-throughput sequencing of the 16S rRNA gene, the archaeal and bacterial composition was determined from phylum to species level in the different plot treatments. The relative abundance of these taxes was correlated with measured soil properties. The P, Mg, total organic carbon, total N and mineral N were significantly higher in the no-tillage system. The microbial diversity was higher in the notillage system at order, family, genus and species level. In addition, overall microbial composition changed significantly between conventional tillage and no-tillage systems. Anaerobic bacteria, such as clostridia, dominate in no-tilled soil as well as anaerobic methanogenic archaea, which were detected only in the no-tillage system. Microbial diversity was higher in plots in which only cereals (oat and maize) were grown. Soil management influenced soil biodiversity on Acrisol by change of composition and abundance of individual species. OPEN ACCESSDiversity 2012, 4 376

show abstract

Section: Discussionmentioning

confidence: 55%

The Effect of Tillage System and Crop Rotation on Soil Microbial Diversity and Composition in a Subtropical Acrisol

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Several workers have reported a stimulatory effect of plants on the net mineralisation of soil organic nitrogen (N) (BiUes et al, 1986;Clarholm, 1985a;Haider et al, 1989;Hart et al, 1979;Wheatley et al, 1990). The reason for this enhancement is uncertain.…”

Section: Introductionmentioning

confidence: 99%

“…In these current models we assess if the amount of N made available through rootinduced N mineralisation represents a significant proportion of the total amount of N taken up by the plant. More recent experimental evidence has shown that the population of fauna in the rhizosphere of 4 crop plants was sufficient only to supply a small proportion of the plants' N requirements (Griffiths et al, 1991;Wheatley et al, 1990). In view of these latter observations, the theoretical basis of root-induced N mineralisation is further examined.…”

Section: Introductionmentioning

confidence: 99%

Root-induced nitrogen mineralisation: A nitrogen balance model

Griffiths¹,

Robinson²

1992

Plant Soil

Self Cite

View full text Add to dashboard Cite

The possibility is examined that carbon (C) released into the soil from a root could enhance the availability of nitrogen (N) to plants by stimulating microbial activity. Two models are described, both of which assume that C released from roots is used by bacteria to mineralise and immobilise soil organic N and that immobilised N released when bacteria are grazed by bacterial-feeding nematodes or protozoa is taken up by the plant. The first model simulates the individual transformations of C and N and indicates that root-induced N mineralisation could supply only up to 10% of the plant's requirement, even if unrealistically ideal conditions are assumed. The other model is based on evidence that about 40% of immobilised N is subsequently taken up by the plant. A small net gain of N by the plant is shown (i.e. the plant takes up more N than it loses through exudation), although with exudate of up to C : N 33:1 less than 6% of the plant's requirement is supplied by root-induced N mineralisation. It is argued, however, that rhizosphere bacteria do not use plant-derived C to mineralise soil organic N to any great extent and that in reality root-induced N mineralisation is even less important than these models indicate.

show abstract

“…A relação C:N da biomassa microbiana geralmente apresenta uma correspondência com a relação C:N dos resíduos orgânicos adicionados ao solo (Gunapala & Scow, 1998) e é uma resposta à disponibilidade de N (Salinas-Garcia et al, 1997) e à qualidade dos resíduos. Palhas de cereais são decompostas principalmente por fungos, cuja relação C:N é mais elevada do que bacté-rias e actinomicetos (Wheatley et al, 1990;Garcia & Rice, 1994).…”

Section: Resultsunclassified

“…A mudança na relação C:N da biomassa microbiana pode ser o resultado de modificações na sucessão microbiana ou de adaptações no conteúdo interno de fungos (Mary et al, 1996) e está associada com a disponibilidade de nitrogênio. Embora alguns indivíduos ou populações possam ajustar a sua relação C:N à do substrato, é pouco provável que toda a comunidade microbiana apresente este comportamento (Wheatley et al, 1990). O mais provável é que a diminuição da relação C:N tenha ocorrido em razão do aumento da população bacteriana em resposta às aplicações de uréia (Garcia & Rice, 1994).…”

Section: Resultsunclassified

Alterações microbianas no solo durante o ciclo do milho nos sistemas plantio direto e convencional

Vargas

Selbach

Sá

2004

Pesq. agropec. bras.

View full text Add to dashboard Cite

Resumo -A disponibilidade de resíduos de aveia-preta, com relação C:N elevada, resulta em imobilização microbiana de nitrogênio no solo, exigindo cuidados no manejo da adubação nitrogenada da cultura subseqüente. O objetivo deste trabalho foi avaliar as alterações na estrutura da comunidade microbiana ao longo do ciclo do milho, na presença de resíduos de aveia-preta e da aplicação de nitrogênio. Foram coletadas amostras de um Argissolo Vermelho distrófico no dia da semeadura do milho e 46, 62, 88 e 112 dias após a semeadura. O nitrogênio foi aplicado 25 dias e 49 dias após a semeadura. As alterações na comunidade microbiana foram avaliadas mediante relações entre carbono (C) e nitrogênio (N), nitrogênio reativo com ninidrina (N-Nin) e carboidratos (CHO) da biomassa microbiana, além da análise do rDNA fúngico e bacteriano. As diferenças na composição da comunidade microbiana, reveladas pela análise do rDNA, relacionaram-se mais com as relações C:N e C:N-Nin do que com a relação C:CHO. As relações C:N-Nin e C:N e as avaliações do rDNA mostraram um predomínio inicial de população fúngica. Com a aplicação de N, a população bacteriana tornou-se preponderante e, ao final do ciclo do milho, retornou para uma condição semelhante à inicial.Termos para indexação: biomassa microbiana, PCR, preparos de solo, imobilização de nitrogênio, Zea mays. Microbial changes in soil during a maize crop season in no-till and conventional systemsAbstract -The availability of black oat residues, with high C:N ratio, leads to microbial immobilization of soil nitrogen, demanding special strategies to supply nitrogen to subsequent crops. The objective of this work was to evaluate shifts in microbial community structure due to the availability of black oat residues and nitrogen applications during the corn growing season. Soil (Paleudult) samples were collected on the day of the corn seeding and after 46, 62, 88 and 112 days. Nitrogen fertilizer was applied 25 and 49 days after corn seeding. Changes in microbial community were assessed by microbial biomass carbon (C) and nitrogen (N), ninhydrinreactive N (N-Nin) and carbohydrates (CHO) ratios, besides the analysis of the rDNA of bacteria and fungi. Changes in microbial community shown by rDNA analysis were more related to C:N and C:N-Nin ratios than to C:CHO ratio. The C:N and C:N-Nin ratios and the analysis of the rDNA showed that microbial community was predominantly fungal at the beginning of the evaluation period. After nitrogen application, the bacterial population became preponderant and, at the end of the evaluation period, microbial community turned back to a composition similar to the initial.

show abstract

Microbial biomass and mineral N transformations in soil planted with barley, ryegrass, pea or turnip

Cited by 74 publications

References 51 publications

The Effect of Tillage System and Crop Rotation on Soil Microbial Diversity and Composition in a Subtropical Acrisol

The Effect of Tillage System and Crop Rotation on Soil Microbial Diversity and Composition in a Subtropical Acrisol

Root-induced nitrogen mineralisation: A nitrogen balance model

Alterações microbianas no solo durante o ciclo do milho nos sistemas plantio direto e convencional

Contact Info

Product

Resources

About