The morphological and molecular characterization of Trichoderma spp. in cocoa agroforestry systems

Species of the genus Trichoderma have been used as growth inhibitors and regulators of phytopathogens. The aim of this work was to study and molecularly characterize the species of the genus Trichoderma that can be found in the rhizosphere of cocoa agroforestry systems in the state of Tabasco, Mexico. Four composite samples were taken from each of three municipalities (Cardenas, Comacalco and Cunduacan). Thirty homogeneous sub-samples were taken (0-30 cm of depth) from each site (plantation) in a random zig-zag pattern across the middle part of the plantations, avoiding the edges. Thirteen strains of the Trichoderma genus were isolated and morphologically identified, while two species, T. harzianum and T. koningiopsi, were molecularly identified. Of the 13 strains, only five were amplified, and of these five, four corresponded to T. harzianum and one to T. koningiopsi

The Cacao Agrosystems in Tabasco, México

The cacao agrosystems are very suitable for reforesting completely cleared areas and can become biological corridors between segments of the forest, allowing the repopulation of birds, mammals, reptiles, and amphibians, among others. Cacao (Theobroma cacao L.) is one of the most important tropical crops both nationally and internationally. However, by appropriate management of cacao crops and the inclusion of aggregate values in forest, fruit, vegetables, and ornamental production, as organic cultivation, specific varieties of plants could generate significant income for small producers in the Southeast from Mexico. This cacao agrosystem is involved in erosion, soil fertility, plant nutrition, water quantity and quality, carbon sequestration, reduction of greenhouse gas emissions, and soil biodiversity

Trichoderma ROLE IN AGROFORESTRY-CACAOTAL SYSTEMS AS AN ANTAGONAL AGENT

Agricultural and cocoa agroforestry systems are important for food production and biodiversity conservation. Among this diversity there is a group of fungi of the genus Trichoderma that present antagonistic effects against phytopathogens and this action can be used as a form of biological control of plant pathogens. In the agroforestry-cacao system the diseases with the highest frequency and with the greatest impact on cocoa production (Theobroma cacao) are black rot (Phytophthora spp.), Broom broom (Moniliophthora perniciosa) and moniliasis (Moniliophthora roreri). The objective of this work was to perform an analysis of the main theoretical and practical aspects about the genus Trichoderma and its role in agriculture as an antagonistic agent. One of the microscopic features in the delimitation of the genus, especially by the presence of structures called phalid. The antagonistic mechanisms used by Trichoderma spp. Are described as competition, antibiosis and mycoparasitism. Mycoparasitism is having a relevance on the implications of extracellular enzymes such as chitinases, cellulases, β-1-3-glucanases and proteases that lyse or digest the walls of fungi, Moniliophthora roreri disease. This fungus can inhibit the growth of other fungi and bacteria by producing several volatile and non-volatile secondary metabolites. On the other hand, it participates in the production of regulators of growth and stimulation of the division, differentiation and cellular growth in the plant by the elicitor agent. Trichoderma species that are commercialized for biological control, growth promoter and biofertilizer are T. viride, T. polysporum and T. harzianum. The T. virens and T. harzianum species are most used for the antagonistic control of M. roreri, Phytophthora spp., and M. perniciosa in agroforestry-cacao systems (Theobroma cacao L.) with optimal results to the inhibitory effect for these diseases

The Production and Marketing Issues of Pineapple (<em>Ananas comosus</em>) under Humid Tropical Conditions in the State of Tabasco and Way-out

Pineapple cultivation has had the greatest impact on the market and that has increased world production in the recent decades in all tropical and subtropical areas. It is one of the crops that best adapts to these environmental conditions. In Mexico, its production has decreased significantly. Tabasco pineapple producers have been facing various problems that have further worsened. The main causes of the crisis are increase in input costs, lack of provision of technical advice to small and medium producers, little support of field programs by the government, and the growth of imports of industrialized pineapple. At the same time, the problem is seen during the cultivation of pineapple in the field. The producer sows the plant with fertilization without having chemical tests of the soil and irrigation waterdue to the costs and no interpretation of the results of these soil analyses. This affects the harvest and quality of the pineapple in its sale price

Rendimiento y valor nutritivo del pasto mulato (Brachiaria hibrido, 36061) en respuesta al pastoreo: Performance and nutritive value of mulato grass (Hybrid brachiaria, 36061) in response to grazing

El objetivo de esta investigación fue determinar el rendimiento de materia seca (RMS), tasa de acumulación neta de forraje (TANF), y valor nutritivo del pasto mulato (VNPM), a diferente manejo de pastoreo en diferentes épocas del año. Los tratamientos se distribuyeron aleatoriamente en un diseño de bloques al azar con arreglo factorial 3 x 2, con tres repeticiones (Frecuencias: 14, 21 y 28 días; Intensidad de pastoreo: 9 a 11 y 13 a 15 cm.&nbsp; El pasto mulato presentó mayor acumulación de forraje, aparición de tallos y recambio de tejido foliar en la época de lluvias y nortes. Con pastoreo cada 28 días, a intensidad de 13-15 cm se obtuvo mayor acumulación de forraje (6732 kg MS ha-1), TANF (47 kg MS ha-1 dia-1) y altura de planta (35 cm), con una proporción de hojas y tallos de 5197 y 1473 kg MS ha-1, que propició una disminución en la relación hoja:tallo y una tasa de crecimiento foliar de 4.8 cm tallo-1 dia-1). Al ampliar el intervalo de pastoreo de 14 a 28 días, disminuyó la aparición y densidad de tallos (p&lt;0.05) y aumentó el peso de este (p&lt;0.05), en este sentido la MS digestible y el contenido de PC disminuyeron. En la época de seca no presentó síntomas de marchites y conservo un color verde en sus hojas, lo cual se observó en el crecimiento foliar. En conclusión, se debe pastorear cada 21 d a una intensidad ligera, en época de lluvias, nortes y secas cada 28 d

Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

Design and baseline characteristics of the finerenone in reducing cardiovascular mortality and morbidity in diabetic kidney disease trial

Background: Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials. Patients and Methods: The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate >= 25 mL/min/1.73 m(2) and albuminuria (urinary albumin-to-creatinine ratio >= 30 to <= 5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level alpha = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. Conclusions: FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen. Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049

Diversidad bacteriana en el tracto digestivo de la lombriz de tierra Pontoscolex corethrurus.

El objetivo del presente trabajo fue estudiar la diversidad bacteriana en el contenido digestivo de la lombriz de tierra endogea Pontoscolex corethrurus. El muestreo de la especie P. corethrurus se realizó en dos localidades de Veracruz, México: Plan de las Hayas, zona ganadera con suelo arcilloso y La Mancha, zona de reserva ecológica y con suelo arenoso. El intestino de las lombrices fue dividido en cuatro secciones (A, B, C y D). Bajo condiciones asépticas, se prepararon diluciones decimales con el contenido intestinal empleando el medio líquido Brain Heart Infusion. Posteriormente, la suspensión del contenido intestinal se sembró en medios específicos. La identificación taxonómica de los aislamientos bacterianos puros se realizó por dos procedimientos: 1﴿ pruebas bioquímicas empleando kits de biomerieux API20E®, API20NE® y el software apiwebTM, y 2﴿ la amplificación y secuenciación del gen 16rRNA bacteriano. Se observó que el número de las las poblaciones bacterianas aisladas del contenido intestinal de P. corethrurus presentaron un mismo comportamiento en ambas localidades, aumento en la sección B y disminución de la sección C a la sección D. En Plan de las Hayas fueron identificadas con el sistema API® trece especies de bacterias: Aeromonas hydrophila/caviae, A. salmonicida ssp salmonicida, Burkholderia cepacia, Ochrobactrum anthropi, Photobacterium damselae, Pseudomonas aeruginosa, P. fluorescens, P. putida, P. luteola, Psychrobacter phenylpyruvicus, Shewanella putrefaciens, Sphingomonas paucimobilis y Vibrio parahaemolyticus. En la Mancha fueron identificadas siete géneros de bacterias en el contenido intestinal de P. corethurus: Aeromonas hydrophila/caviae, Burkholderia cepacia, Ochrobactrum anthropi, Photobacterium damselae, Pseudomonas aeruginosa, P. fluorescens, P. putida, P. luteola, Shewanella putrefaciens y Sphingomonas paucimobilis. Con el uso de la secuenciación del gen 16S ADNr en las bacterias aisladas del contenido intestinal de P. corethrurus fueron identificadas siete géneros en Plan de las Hayas (Bacillus, Bacterium, Pseudomonas, Acinetobacter, Massilia, Aeromonas y Citrococcus) y en la Mancha cuatro géneros de bacterias (Bacillus, Terribacillus, Bacterium y Aeromonas). Los resultados obtenidos a través de la secuenciación y alineamiento de la región 16s rARN fueron diferentes a los obtenidos con el sistema API®. Se considera que el limitado número de aislamientos de bacterias estudiadas no permitió establecer una clara relación entre las variantes de reacciones enzimáticas con el sistema API®. No fue posible realizar pruebas metabólicas adicionales, pero la amplificación del gen 16s ARNr permitió discriminar a nivel de especie y mejorar el diagnóstico bacteriológico. En ambos sitios se observó diferencias filogenéticas y metabólicas en los géneros de las bacterias aisladas del contenido intestinal P. corethrurus. Estas diferencias se pueden deber al tipo de suelo, contenido de C, N y al tipo de ecosistema. Las enzimas catalasa, oxidasa, gelatinasa, citratasa, triptofanasa y cisteinasa, presentes en las bacterias que son ingeridas junto con el suelo por la lombriz de tierra geófaga, permiten la degradación y/o digestión de la materia orgánica estableciendose así un mutualismo anisosimbiótico entre bacterias y lombriz (paradigma de la bella durmiente﴿. La interacción entre las bacterias y el intestino de P. corethrurus contribuye a los servicios de los ecosistemas, al participar directamente en la explotación, degradación, neoformación y reciclaje de los recursos orgánicos y minerales del suelo. _______________ ABSTRACT: The objective of this work was to study the bacterial diversity within the digestive tract of the endogeic earthworm Pontoscolex corethrurus. Sampling of P. corethrurus was carried out in two localities in Veracruz, Mexico; “Plan de las Hayas”, a livestock zone with clayey soil and “La Mancha”, an ecological reserve zone with sandy soil. The intestines of the earthworms were divided in four sections (A, B, C, and D). Under aseptic conditions, the intestinal content was diluted with Brain Heart Infusion liquid medium. Subsequently, the diluted suspension containing the intestinal content was grew on plates of specific media. Taxonomic identification of pure bacterial isolates was done by two processes: 1) biochemical test using API20E® and API20NE® biomerieux kits and ApiwebTM software, and 2) the amplification and sequencing of bacterial 16r RNA gene. It was observed that the bacterial populations isolated from the intestinal content of P. corethrurus form both localities presented the same behavior: increase in section B and decrease in section C to D. In “Plan de las Hayas” 13 bacterial species were identified with the API® system and are as follows: Aeromonas hydrophila/caviae, A. salmonicidas sp salmonicida, Burkholderia cepacia, Ochrobactru manthropi, Photobacterium damselae, Pseudomonas aeruginosa, P. fluorescens, P. putida, P. luteola, Psychrobacter phenylpyruvicus, Shewanella putrefaciens, Sphingomonas paucimobilis andVibrio parahaemolyticus. In “La Mancha” nine bacteria species were identified within the intestinal content of P. corethrurus: Aeromonas hydrophila/caviae, Burkholderia cepacia, Ochrobactruman thropi, Photobacterium damselae.The sequencing of the 16S rDNA bacterial region showed seven genera from “Plan de las Hayas”(Bacillus, Bacterium, Pseudomonas, Acinetobacter, Massilia, Aeromonas andCitrococcus) and four from “La Mancha” (Bacillus, Terribacillus, Bacterium y Aeromonas). However, the results from API® system were not similar of those obtained from sequencing and alignment of 16S rRNA region. Finally, it was considered that the limited number of bacterial isolations studied did not allow the establishment of a clear relationship among the variants of the enzymatic reactions with the API® system. Additional metabolic tests were not made but the amplification of 16S rRNA permitted the discrimination at species level to improve the bacteriological diagnosis. In both sites, phylogenic and metabolic differences were observed in the bacterial genera isolated from the digestive tract of P. corethrurus. These differences may be due to soil type, C an N content as well as the ecosystem type. The enzymes catalase, oxidase, gelatinase, citratase, tryptophanase and cysteinaseare, present in the bacteria which are ingested together with soil by the geophagous earthworm, promote the degaradation and transformation of organic matter, establishing in this way an anisosymbiotic mutualism (sleeping beauty paradigm). The interaction among the bacteria and the digestive tract of P. corethrurus contributed to the services of the ecosystems, exploiting and degrading the organic and mineral soil resources.Tesis (Doctorado en Ciencias, especialista en Edafología).- Colegio de Postgraduados, 2010.Consejo Nacional de Ciencia y Tecnología (CONACYT﴿

THE SOIL BIOTA: IMPORTANCE IN AGROFORESTRY AND AGRICULTURAL SYSTEMS

The biological component of soil is important for the maintenance and functioning of ecosystems. Currently there have been some studies on the diversity of soil biota and their role in key soil processes. Microorganisms are critical to the functioning of biological systems and the maintenance of life on the planet, since they participate in metabolic, ecological and biotechnological processes on which we depend for survival and for facing future challenges. Soil organisms maintain soil processes such as carbon capture and storage, nutrient cycling, nitrogen fixation, water infiltration, aeration, and organic matter degradation. The effects of these ecosystem services are not yet fully explored, especially soil microorganisms (bacteria and fungi), and macro-organisms (earthworms)