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1.
J. P. Pimentel F. Olivares R. M. Pitard S. Urquiaga F. Akiba J. Döbereiner 《Plant and Soil》1991,137(1):61-65
Bacteria causing mottled stripe disease in sugar cane, known asPseudomonas rubrisubalbicans, were shown to be able to fix molecular N2 and to grow on it. The root associated diazotroph known asHerbaspirillum seropedicae, after artificial inoculation caused mottled stripe disease symptoms on sorghum and Napier grass but not on sugar cane. Both bacteria could be reisolated from leaves even 60 days after. Sugar cane leaves contained large numbers of these bacteria even in the uninoculated controls. Additional physiological characteristics of six strains ofP. rubrisubalbicans were compared with those of twoH. seropedicae strains and were shown to be very similar. 相似文献
2.
Inés Urquiaga Sonia D’Acu?a Druso Pérez Sara Dicenta Guadalupe Echeverría Attilio Rigotti Federico Leighton 《Biological research》2015,48(1)
Background
The Mediterranean diet is a healthy diet with positive scientific evidence of preventing chronic diseases. Bioactive components support the healthy properties of the Mediterranean diet. Antioxidants and fiber, two components of the Mediterranean diet, are key functional nutrients for healthy eating and nutrition. Wine grape pomace is a rich source of these dietary constituents and may be beneficial for human health. Our hypothesis was that the intake of red wine grape pomace flour (WGPF) prepared from red wine grapes (Cabernet Sauvignon variety) reduced the metabolic syndrome in humans. To evaluate the effect of WGPF on components of metabolic syndrome we design a 16-week longitudinal intervention study. Thirty-eight males, 30–65 years of age, with at least one component of metabolic syndrome, were randomly assigned to either the intervention group (n = 25) or the control group (n = 13). At lunch, the intervention group was given 20 g of WGPF per day, which contained 10 g of dietary fiber, 822 mg of polyphenols and an antioxidant capacity of 7258 ORAC units. Both groups were asked to maintain their regular eating habits and lifestyles. Clinical evaluation, anthropometric measurements and biochemical blood analyses were done at the beginning and the end of the study.Results
WGPF intake significantly decreased systolic and diastolic blood pressure as well as fasting glucose levels. Plasma γ-tocopherol and δ-tocopherol increased and carbonyl group in plasma protein decreased in WGPT group, significantly. No significant effect was observed for waist circumference, HDL cholesterol, triglycerides, total antioxidant capacity and vitamin C in and between groups. The group-dependent magnitude of the differences between the baseline and final postprandial insulin values and γ-tocopherol concentrations was statistically significant.Conclusions
The consumption of WGPF-rich in fiber and polyphenol antioxidants, as a food supplement in a regular diet improves blood pressure, glycaemia and postprandial insulin. In addition, increased antioxidant defenses and decreased oxidative protein damage indicating attenuation of oxidative stress. WGPF might be a useful food ingredient for health promotion and chronic disease prevention. 相似文献3.
The success of BNF in soybean in Brazil 总被引:6,自引:1,他引:5
Approximately forty years after commercial cropping of soybean in Brazil began, the total area under this crop has reached over 13 M ha with a mean productivity of 2400 kg ha–1. Soybean varieties introduced from the USA and varieties rescued from early introductions in Brazilian territory were part of the Brazilian soybean-breeding programme which spread the crop from high to low latitudes. Disease-resistance, pest-resistance, tolerance to low fertility soils, as well as production of plants with pods sufficiently high above the ground for efficient mechanical harvesting, were all aims of the programme. Although BNF was not explicitly considered as a trait for selection in the breeding/selection programme, maximisation of biological nitrogen fixation (BNF) was favoured by conducting selection and breeding trials on soils low in N, in which the seeds were inoculated with efficient Bradyrhizobium inoculants but without N fertiliser application. Several efficient imported Bradyrhizobium strains were found to be unable to compete with native soil micro-flora and other previously-introduced Bradyrhizobium strains. Surprisingly, after being in the soil for many years one or two of these strains had become more competitive while maintaining their high BNF capacity. Today, these strains are included amongst the recommended Brazilian inoculants and have promoted significant improvements in grain yields. The breeding of soybeans in conditions that made grain yield highly dependent on BNF, and the continuous attention paid to the selection of Bradyrhizobium strains appropriate for the newly released varieties, have been the main contributors to today's high yields and their great benefit to the Brazilian economy. There seems to be no reason why this ongoing research programme should not serve as an appropriate model to improve BNF inputs to grain legumes in other countries of the world. 相似文献
4.
Alexander S. de Resende Rogério P. Xavier Octávio C. de Oliveira Segundo Urquiaga Bruno J. R. Alves Robert M. Boddey 《Plant and Soil》2006,281(1-2):339-351
Since the 1970s the area under sugarcane in Brazil has increased from 2 million to over 5 million ha (M ha), and it is expected
to pass the 7 M ha mark in 2007. More than half of the cane is harvested to produce bioethanol as a fuel for light vehicles.
The distilleries produce approximately 13 L of distillery waste (vinasse) for each litre of ethanol produced. In the 1980s
there was considerable concern over the long-term effects of the disposal of this material (containing about 1% carbon and
high in K) on cane yields if it was applied to the field. At the same time there was a growing movement to abandon the practice
of pre-harvest burning and some research was showing that some Brazilian varieties of sugar cane were able to obtain significant
contributions of N from plant-associated biological nitrogen fixation (BNF). For these reasons an experiment was installed
on a cane plantation in the state of Pernambuco, NE Brazil to investigate the long-term effects of vinasse and N fertiliser
additions and the practice of pre-harvest burning on crop and sugar yield, soil fertility parameters, N balance and soil C
stocks. The results showed that over a 16-year period, trash conservation (abandonment of burning) increased cane yields by
25% from a mean of 46 to 58 Mg ha−1. Vinasse applications (80 m3 ha−1 crop−1) increased mean cane and sugar yield by 12 to 13% and the application of 80 kg N ha−1 as urea increased cane yields by 9%, but total sugar yield by less than 6% (from 7.0 to 7.4 Mg ha−1 crop−1). The total N balance for the soil/plant system when only the surface 20 cm of the soil was considered was positive in plots
where no N fertiliser was added. However, the data indicated that during the 16 years of the study considerable quantities
of soil organic matter were accumulated below 20 cm depth such that the N balance considering the soil to 60 cm depth was
strongly positive, except where N fertiliser was added. The data indicated that there were considerable BNF inputs to the
system, which was consistent with its low response to N fertiliser and low N fertiliser-use-efficiency. There were no significant
effects of vinasse or urea addition, or trash conservation on soil C stocks, although the higher yields proportioned by trash
conservation had potentially significant benefits for increased mitigation of CO2 emissions where the main use of the cane was for bioethanol production. 相似文献
5.
German Andres Estrada Vera Lúcia Divan Baldani Danilo Messias de Oliveira Segundo Urquiaga José Ivo Baldani 《Plant and Soil》2013,369(1-2):115-129
Background and Aims
Plant growth-promoting bacteria, mainly diazotrophs and phosphate solubilizers, can reduce the use of chemical fertilizers for rice crops. Here, diazotrophic bacteria isolated from rice were screened for their ability to solubilize inorganic P (Pi) in vitro and in association with rice plants cultivated in pots.Methods
Forty-nine isolates were tested for the ability to solubilize Pi on NBRIP and GL agar plate media and seven selected strains were further evaluated in NBRIP liquid medium. Three of these strains were inoculated in rice plants grown in soil pots containing 15N-labeled fertilizer and two sources of P: tricalcium phosphate (TCP) or simple superphosphate (SSP). The dry matter, yield, N, P, and the 15N content accumulated in plant tissues were measured at 135 days after planting.Results
Seven strains belonging to the genera Herbaspirillum and Burkholderia formed a halo of solubilized Pi on agar plates. The Burkholderia strains showed peak soluble P (around 200 mg P L?1) on the fifth day when grown in NBRIP liquid medium for 14 days. Inoculation of Herbaspirillum strains (H18, ZA15) and a Burkholderia vietaminensis strain (AR114) increased rice grain yield from 33 to 47 % with TCP and 18 to 44 % with TSS, respectively. The bacterial inoculation led to enhanced N-use efficiency of the 15N-labeled fertilizer.Conclusion
These results suggest that the selection and use of P-solubilizing diazotrophic bacteria are a good strategy to promote P solubilization and/or N use efficiency in rice plants. 相似文献6.
The effect of inoculating endophytic N2-fixing bacteria on micropropagated sugarcane plants 总被引:1,自引:0,他引:1
We investigated the effects of an autumn sowing of contrasting cover crops (oats, rye and a combination of oats and rye) on soil aggregate stability, mycorrhizal colonization, phosphorus uptake and yield of sweet corn planted the following summer. Rye is a common cover crop in the middle Atlantic region of the United States of America. It grows slowly in the autumn, survives the winter, grows rapidly in the spring and flowers in the summer. Thus, herbicide is commonly used to kill rye prior to planting spring crops. Oats, in contrast, grows rapidly in the autumn but is killed by frost during the winter. Thus, with oats, potentially less herbicide is needed to prepare the field for spring planting. When compared to fallow, oats was as effective as rye in increasing mycorrhizal colonization of sweet corn, density of mycorrhizal hyphae, and soil aggregate stability. An oats cover crop may thus be a viable alternative to rye. The combination of cover crops (rye and oats), however, was significantly better than single species of cover crops in terms of sweet corn mycorrhizal colonization, P uptake and yield of sweet corn. 相似文献
7.
In this study the contribution of biological N2 fixation (BNF) to leguminous green manures was quantified in the field at different sites with different 15N methodologies. In the first experiment, conducted on a Terra Roxa soil in Cuba, the BNF contribution to three legumes (Crotalaria juncea, Mucuna aterrima and Canavalia ensiformis) was quantified by applying 15N-labelled ammonium sulphate to the soil. The second experiment was planted in a very low fertility sandy soil near Rio de Janeiro, and the 15N natural abundance technique was applied to quantify BNF in C. juncea, M. niveum and soybean. In both studies the advantages of using several non-N2-fixing reference plants was apparent and despite the much greater accumulation of the C. juncea in the experiment performed on the fertile soil of Cuba, the above ground contributions of BNF at both sites were similar (40-80 kg N x ha(-1)) and greater than for the other legumes. In a further experiment the possible contribution of root-derived N to the soil/plant system of two of the legumes was quantified using a 15N-leaf-labelling technique performed in pots. The results of this study suggested that total below-ground N could constitute as much as 39 to 49% of the total N accumulated by the legume crops. 相似文献
8.
Yield of micropropagated sugarcane varieties in different soil types following inoculation with diazotrophic bacteria 总被引:4,自引:1,他引:3
André Luiz Martinez de Oliveira Erineudo Lima de Canuto Segundo Urquiaga Veronica Massena Reis José Ivo Baldani 《Plant and Soil》2006,284(1-2):23-32
It is well described that the beneficial interactions between plants and bacteria are genotype and site specific. Brazilian
sugarcane varieties can obtain up to 70% of their nitrogen requirement from biological nitrogen fixation (BNF), and this contribution
is related to the Brazilian breeding and selection processes, by example of the variety SP70-1143. In this study the effect
of two inoculation mixtures containing diazotrophic bacteria in our earlier pot experiment was evaluated with two sugarcane
varieties, a known responder, SP70-1143, and a newly selected variety, SP81-3250, to investigate the sugarcane genotype effect
and the role of the mixtures. The sugarcane varieties SP70-1143 and SP81-3250 were grown under commercial field conditions
at three sites with contrasting soil types: an Alfisol, an Oxisol and an Ultisol that means a low, medium and high natural
fertility respectively. The stem yield and BNF contribution in response to bacterial inoculation were influenced by the strain
combinations in the inoculum, the plant genotype, and the soil type and nitrogen fertilization, confirming the genetic and
environmental influence in PGP-bacteria interactions. Inoculation effects on the BNF contribution and stem yield increased
in the variety SP70-1143 grown in the Alfisol without nitrogen fertilization for three consecutive crops, and it was equivalent
to the annual nitrogen fertilization. The plants grown in the Oxisol showed small increases in the productivity of the variety
SP70-1143, and in the Ultisol the sugarcane plants presented even decreases in the stem productivity due to inoculation with
diazotrophic bacteria mixtures. The results demonstrate the feasibility of the inoculation technology using diazotrophic bacteria
in micropropagated sugarcane varieties grown in soils with low to medium levels of fertility. In addition, the results also
indicated that specific plant – bacteria – environment combinations are needed to harness the full benefits of BNF.
Section Editor: C. P. Vance 相似文献
9.
Segundo Urquiaga Rogério P. Xavier Rafael F. de Morais Rafael B. Batista Nivaldo Schultz José M. Leite Jerusa Maia e Sá Karolina P. Barbosa Alexander S. de Resende Bruno J. R. Alves Robert M. Boddey 《Plant and Soil》2012,356(1-2):5-21
Aims
In Brazil N fertilization of sugarcane (Saccharum spp.) is low compared to most other countries. 15N-aided studies and the occurrence of many N2-fixing bacteria associated with cane plants suggest significant contributions from biological N2 fixation (BNF). The objective of this study was to evaluate BNF contributions to nine cane varieties under field conditions using N balance and 15N natural abundance techniques.Methods
The field experiment was planted near Rio de Janeiro in 1989, replanted in 1999 and harvested 13 times until 2004. Soil total N was evaluated at planting and again in 2004. Samples of cane leaves and weeds for the evaluation of 15N natural abundance were taken in 2000, 2003 and 2004.Results
N accumulation of the commercial cane varieties and a variety of Saccharum spontaneum were persistently high and N balances (60 to 107?kg?N ha?1?yr?1) significantly (p?<?0.05) positive. The δ15N of leaf samples were lower than any of the weed reference plants and data obtained from a greenhouse study indicated that this was not due to the cane plants tapping into soil of lower 15N abundance at greater depth.Conclusion
The results indicate that the Brazilian varieties of sugarcane were able to obtain at least 40?kg?N ha?1?yr?1 from BNF. 相似文献10.
Érika Flavia Machado Pinheiro Eduardo Lima Marcos Bacis Ceddia Segundo Urquiaga Bruno J. R. Alves Robert M. Boddey 《Plant and Soil》2010,333(1-2):71-80
Owing to the increased demand for ethanol biofuel from sugar cane, the area planted to this crop in Brazil has increased from 4.8 to 9.5 Mha since 2000. At the same time there has been pressure from environmental groups and others to cease the pre-harvest burning of cane, and today over 40% of the crop is harvested without burning, thus conserving the trash on the soil surface. While most trash decomposes during the year, it is generally assumed that this transition from burning to trash conservation will have benefits for cane productivity and increase soil carbon stocks. To investigate the possible benefits of this change of practice an experiment was carried out in the state of Espírito Santo, south-eastern Brazil, to investigate the long-term effects of the practice of pre-harvested burning compared to trash conservation on soil fertility and soil C and N stocks. The results showed that over a 14-year period, trash conservation marginally decreased soil acidity and significantly increased soil C and N stocks in 0–10 cm depth interval. Although the trash conservation treatment accumulated 13 Mg C ha?1 more than the burned treatment, this difference was not statistically different. However, the stocks of N to 100 cm depth were 900 kg ha?1 higher under the trash conservation treatment and this difference was statistically significant. The 13C abundance data suggested that where trash was conserved, more soil C was derived from the sugar cane than from the original native vegetation. 相似文献