Metabolomics and microbiome reveal impacts of rhizosphere metabolites on alfalfa continuous cropping

Alfalfa long-term continuous cropping (CC) can pose a serious threat to alfalfa production. However, the mechanism of alfalfa CC obstacle is unclear as of today. In this study, we determined physic-chemical property, microbial population structure, and metabolite differences of alfalfa rhizosphere soils with CC for 1, 7, and 14-years based on analysis of metabolomics and microbiomics. Shifts of functional microorganisms in rhizosphere soil were analyzed, key metabolites and their effects on alfalfa seeds, seedlings and root rot pathogens were assessed. Based on anlysis, p-coumaric acid and ferulic acid on alfalfa seed and seedling growth and root rot pathogens were basically consistent with the influence of CC obstacles in the field. With the increase of CC years, the microbial community in soils changed from fungal to bacterial, and beneficial microorganisms decreased with the increase of CC years, which echoed the performance of alfalfa CC obstacles. The autotoxicity of p-coumaric acid was the strongest.This study fully proved that the continuous accumulation of autotoxic substances in alfalfa rhizosphere was the key factor causing alfalfa CC obstacles.

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Rhizosphere Bacterial Community Response to Continuous Cropping of Tibetan Barley

Frontiers in Microbiology ◽

10.3389/fmicb.2020.551444 ◽

2020 ◽

Vol 11 ◽

Author(s):

Youhua Yao ◽

Xiaohua Yao ◽

Likun An ◽

Yixiong Bai ◽

Deqing Xie ◽

...

Keyword(s):

Bacterial Community ◽

Total Nitrogen ◽

Rhizosphere Soil ◽

Community Response ◽

16S Rrna Genes ◽

Rrna Genes ◽

Continuous Cropping ◽

Health Maintenance ◽

Rhizosphere Bacterial Community

Long-term continuous cropping influences the nutrient of soil and microbiome of the rhizosphere, resulting in the yield decrease of crops. Tibetan barley is a dominant cereal crop cultivated at high altitudes in Tibet. Its growth and yield are negatively affected by continuous cropping; however, the response of the rhizosphere microbial community to continuous cropping remains poorly understood. To address this question, we investigated the bacterial community structure and conducted predictive functional profiling on rhizosphere soil from Tibetan barley monocropped for 2–6 years. The results revealed that long-term continuous cropping markedly decreased total nitrogen and available nitrogen in rhizosphere soil. Illumina high-throughput sequencing of 16S rRNA genes indicated that the bacterial community was altered by continuous cropping; operational taxonomic units (OTUs), Shannon index, and Faith Phylogenetic Diversity decreased with increasing monocropping duration. Relative abundances of family Pseudomonadaceae, Cytophagaceae, and Nocardioidaceae were significantly increased, while those of Chitinophagaceae and Sphingomonadaceae were significantly decreased (all p < 0.05). Besides, continuous cropping significantly increased the abundance of bacteria associated with chemoheterotrophy, aromatic compound degradation, and nitrate reduction (p < 0.05). Generalized boosted regression model analysis indicated that total nitrogen was the most important contributor to the bacterial community diversity, indicating their roles in shaping the rhizosphere bacterial community during continuous cropping. Overall, continuous cropping had a significant impact on the structure of bacterial communities in rhizosphere soil of Tibetan barley, and these results will improve our understanding of soil bacterial community regulation and soil health maintenance in Tibetan barley farm systems.

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EFFECT OF LONG-TERM CONTINUOUS CROPPING OF SPRING WHEAT ON AGGRESSIVENESS OF Cochliobolus sativus

Canadian Journal of Plant Science ◽

10.4141/cjps89-051 ◽

1989 ◽

Vol 69 (2) ◽

pp. 395-400 ◽

Cited By ~ 16

Author(s):

H. M. EL-NASHAAR ◽

R. W. STACK

Keyword(s):

Spring Wheat ◽

Root Rot ◽

Wheat Root ◽

Cochliobolus Sativus ◽

Continuous Cropping ◽

Surrounding Area ◽

Helminthosporium Sativum ◽

Wheat Plot

Cochliobolus sativus cultures were collected from symptomatic wheat plants from a plot planted continuously to wheat for over 90 yr and from symptomatic wheat plants in commercial grain fields cropped rotationally in the surrounding area. Pathogenicity of these isolates was tested in replicated greenhouse trials using wheat plants scored for disease 6 wk after inoculation. Isolates from the continuous-cropped wheat plot were more aggressive on average than were isolates from commercial fields. Long-term continuous cropping to wheat appears to shift the population of C. sativus toward more aggressive types, although many less aggressive types also remain.Key words: Aggressiveness, Drechslera sorkiniana, Helminthosporium sativum, wheat root rot

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Rhizosphere Soil Bacterial Communities of Continuous Cropping-Tolerant and Sensitive Soybean Genotypes Respond Differently to Long-Term Continuous Cropping in Mollisols

Frontiers in Microbiology ◽

10.3389/fmicb.2021.729047 ◽

2021 ◽

Vol 12 ◽

Author(s):

Ming Yuan ◽

Taobing Yu ◽

Qihan Shi ◽

Dongwei Han ◽

Kanchao Yu ◽

...

Keyword(s):

Microbial Community ◽

Soybean Cyst Nematode ◽

High Throughput Sequencing ◽

Rhizosphere Soil ◽

Continuous Cropping ◽

Cyst Nematodes ◽

Short Term ◽

Soybean Genotypes ◽

Soil Bacterial

The continuous planting of soybeans leads to soil acidification, aggravation of soil-borne diseases, reduction in soil enzyme activity, and accumulation of toxins in the soil. Microorganisms in the rhizosphere play a very important role in maintaining the sustainability of the soil ecosystem and plant health. In this study, two soybean genotypes, one bred for continuous cropping and the other not, were grown in a Mollisol in northeast China under continuous cropping for 7 and 36years in comparison with soybean–maize rotation, and microbial communities in the rhizosphere composition were assessed using high-throughput sequencing technology. The results showed that short- or long-term continuous cropping had no significant effect on the rhizosphere soil bacterial alpha diversity. Short-term continuous planting increased the number of soybean cyst nematode (Heterodera glycines), while long-term continuous planting reduced these numbers. There were less soybean cyst nematodes in the rhizosphere of the tolerant genotypes than sensitive genotypes. In addition, continuous cropping significantly increased the potential beneficial bacterial populations, such as Pseudoxanthomonas, Nitrospira, and Streptomyces compared to rotation and short-term continuous cropping, suggesting that long-term continuous cropping of soybean shifts the microbial community toward a healthy crop rotation system. Soybean genotypes that are tolerant to soybean might recruit some microorganisms that enhance the resistance of soybeans to long-term continuous cropping. Moreover, the network of the two genotypes responded differently to continuous cropping. The tolerant genotype responded positively to continuous cropping, while for the sensitive genotype, topology analyses on the instability of microbial community in the rhizosphere suggested that short periods of continuous planting can have a detrimental effect on microbial community stability, although this effect could be alleviated with increasing periods of continuous planting.

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Effect of Autotoxicity and Soil Microbes in Continuous Cropping Soil on Angelica sinensis Seedling Growth and Rhizosphere Soil Microbial Population

Chinese Herbal Medicines ◽

10.1016/s1674-6384(15)60025-9 ◽

2015 ◽

Vol 7 (1) ◽

pp. 88-93 ◽

Cited By ~ 5

Author(s):

Zhang Xin-hui ◽

Duo-yong Lang ◽

En-he Zhang ◽

Zhi-sheng Wang

Keyword(s):

Seedling Growth ◽

Soil Microbes ◽

Microbial Population ◽

Rhizosphere Soil ◽

Angelica Sinensis ◽

Continuous Cropping ◽

Soil Microbial ◽

Soil Microbial Population

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Attachment of oral bacteria to titanium surfaces: An SEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170074 ◽

1994 ◽

Vol 52 ◽

pp. 468-469

Author(s):

J. E. Laffoon ◽

R. L. Anderson ◽

J. C. Keller ◽

C. D. Wu-Yuan

Keyword(s):

Technical Problem ◽

Titanium Implant ◽

Oral Bacteria ◽

Bacterial Cells ◽

Thin Sections ◽

Surface Ultrastructure ◽

Sem Study ◽

Key Factor ◽

Titanium Surfaces

Titanium (Ti) dental implants have been used widely for many years. Long term implant failures are related, in part, to the development of peri-implantitis frequently associated with bacteria. Bacterial adherence and colonization have been considered a key factor in the pathogenesis of many biomaterial based infections. Without the initial attachment of oral bacteria to Ti-implant surfaces, subsequent polymicrobial accumulation and colonization leading to peri-implant disease cannot occur. The overall goal of this study is to examine the implant-oral bacterial interfaces and gain a greater understanding of their attachment characteristics and mechanisms. Since the detailed cell surface ultrastructure involved in attachment is only discernible at the electron microscopy level, the study is complicated by the technical problem of obtaining titanium implant and attached bacterial cells in the same ultra-thin sections. In this study, a technique was developed to facilitate the study of Ti implant-bacteria interface.Discs of polymerized Spurr’s resin (12 mm x 5 mm) were formed to a thickness of approximately 3 mm using an EM block holder (Fig. 1). Titanium was then deposited by vacuum deposition to a film thickness of 300Å (Fig. 2).

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Designing a CRM Framework for online & offline sports footwear retailers

"Carácter" Revista Cientifica de la Universidad Del Pacifico ISSN 2602-8476 ◽

10.35936/caracter.v3i1.41 ◽

2015 ◽

Vol 3 (1) ◽

Author(s):

Rodrigo Cueva ◽

Guillem Rufian ◽

Maria Gabriela Valdes

Keyword(s):

Environmental Changes ◽

Customer Relationship ◽

Business Strategies ◽

Economic Sectors ◽

Running Shoes ◽

Brick And Mortar ◽

Key Factor ◽

On Line ◽

The Impact

The use of Customer Relationship Managers to foster customers loyalty has become one of the most common business strategies in the past years. However, CRM solutions do not fill the abundance of happily ever-after relationships that business needs, and each client’s perception is different in the buying process. Therefore, the experience must be precise, in order to extend the loyalty period of a customer as much as possible. One of the economic sectors in which CRM’s have improved this experience is retailing, where the personalized attention to the customer is a key factor. However, brick and mortar experiences are not enough to be aware in how environmental changes could affect the industry trends in the long term. A base unified theoretical framework must be taken into consideration, in order to develop an adaptable model for constructing or implementing CRMs into companies. Thanks to this approximation, the information is complemented, and the outcome will increment the quality in any Marketing/Sales initiative. The goal of this article is to explore the different factors grouped by three main domains within the impact of service quality, from a consumer’s perspective, in both on-line and off-line retailing sector. Secondly, we plan to go a step further and extract base guidelines about previous analysis for designing CRM’s solutions focused on the loyalty of the customers for a specific retailing sector and its product: Sports Running Shoes.

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Hepato-renal protective effects of gallic acid and p-coumaric acid in nicotinamide/streptozotocin-induced diabetic rats

International Journal of Bioassays ◽

10.21746/ijbio.2016.06.0011 ◽

2016 ◽

Vol 5 (06) ◽

pp. 4641 ◽

Cited By ~ 5

Author(s):

Adel Abdel Moneim* ◽

Sanaa M. Abd El-Twab ◽

Mohamed B. Ashour ◽

Ahmed I. Yousef

Keyword(s):

Body Weight ◽

Gallic Acid ◽

Protein Profile ◽

Serum Glucose ◽

Diabetic Rats ◽

Hypoglycemic Agents ◽

Protective Effects ◽

Coumaric Acid ◽

Experimental Type

The goal of diabetes treatment is primarily to save life and alleviate symptoms and secondary to prevent long-term diabetic complications resulting from hyperglycemia. Thus, our present investigation was designed to evaluate the hepato-renal protective effects of gallic acid and p-coumaric acid in nicotinamide/streptozotocin (NA/STZ)-induced diabetic rats. Experimental type 2 diabetes was induced by a single intraperitoneal (i.p.) injection of STZ (65 mg/kg b.wt.), after 15 min of i.p. injection of NA (120 mg/kg b.wt.). Gallic acid and p-coumaric acid were orally administered to diabetic rats at a dose of 20, 40 mg/kg b.wt./day, respectively, for 6 weeks. Body weight, serum glucose, protein profile, liver function enzymes and kidney function indicators was assayed. Treatment with either gallic acid or p-coumaric acid significantly ameliorated the elevated levels of glucose, alanine aminotransferase (ALT), aspartate aminotransferase (AST), urea and uric acid. Both compounds were also found to restore total protein, albumin, and globulin as well as body weight of diabetic rats to near normal values. It can conclude that both gallic acid and p-coumaric acid have potent hypoglycemic and hepato-renal protective effects in diabetic rats. Therefore, our results suggest promising hypoglycemic agents that can attenuate the progression of diabetic hepatopathy and nephropathy.

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Contributions to Management Strategies in the NE Atlantic Regarding the Life History and Population Structure of a Key Deep-Sea Fish (Mora moro)

Biology ◽

10.3390/biology10060522 ◽

2021 ◽

Vol 10 (6) ◽

pp. 522

Author(s):

Régis Santos ◽

Wendell Medeiros-Leal ◽

Osman Crespo ◽

Ana Novoa-Pabon ◽

Mário Pinho

Keyword(s):

Population Structure ◽

Life History ◽

Deep Sea ◽

Management Strategies ◽

Size Composition ◽

Large Size ◽

The Common ◽

Fishing Impacts ◽

Sea Fish

With the commercial fishery expansion to deeper waters, some vulnerable deep-sea species have been increasingly captured. To reduce the fishing impacts on these species, exploitation and management must be based on detailed and precise information about their biology. The common mora Mora moro has become the main deep-sea species caught by longliners in the Northeast Atlantic at depths between 600 and 1200 m. In the Azores, landings have more than doubled from the early 2000s to recent years. Despite its growing importance, its life history and population structure are poorly understood, and the current stock status has not been assessed. To better determine its distribution, biology, and long-term changes in abundance and size composition, this study analyzed a fishery-dependent and survey time series from the Azores. M. moro was found on mud and rock bottoms at depths below 300 m. A larger–deeper trend was observed, and females were larger and more abundant than males. The reproductive season took place from August to February. Abundance indices and mean sizes in the catch were marked by changes in fishing fleet operational behavior. M. moro is considered vulnerable to overfishing because it exhibits a long life span, a large size, slow growth, and a low natural mortality.

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