Policing the legume-Rhizobium symbiosis: a critical test of partner choice

In legume-Rhizobium symbioses, specialised soil bacteria fix atmospheric nitrogen in return for carbon. However, ineffective strains can arise, making discrimination essential. Discrimination can occur via partner choice, where legumes prevent ineffective strains from entering, or via sanctioning, where plants provide fewer resources. Several studies have inferred that legumes exercise partner choice, but the rhizobia compared were not otherwise isogenic. To test when and how plants discriminate ineffective strains we developed sets of fixing and non-fixing strains that differed only in the expression of nifH - essential for nitrogen fixation - and could be visualised using marker genes. We show that the plant is unable to select against the non-fixing strain at the point of entry, but that non-fixing nodules are sanctioned. We also used the technique to characterise mixed nodules (containing both a fixing and a non-fixing strain), whose frequency could be predicted using a simple diffusion model. We discuss that sanctioning is likely to evolve in preference to partner choice in any symbiosis where partner quality cannot be adequately assessed until goods or services are actively exchanged

EcoTILLING in Capsicum species: searching for new virus resistances

<p>Abstract</p> <p>Background</p> <p>The EcoTILLING technique allows polymorphisms in target genes of natural populations to be quickly analysed or identified and facilitates the screening of genebank collections for desired traits. We have developed an EcoTILLING platform to exploit <it>Capsicum </it>genetic resources. A perfect example of the utility of this EcoTILLING platform is its application in searching for new virus-resistant alleles in <it>Capsicum </it>genus. Mutations in translation initiation factors (eIF4E, eIF(iso)4E, eIF4G and eIF(iso)4G) break the cycle of several RNA viruses without affecting the plant life cycle, which makes these genes potential targets to screen for resistant germplasm.</p> <p>Results</p> <p>We developed and assayed a cDNA-based EcoTILLING platform with 233 cultivated accessions of the genus <it>Capsicum</it>. High variability in the coding sequences of the <it>eIF4E </it>and <it>eIF(iso)4E </it>genes was detected using the cDNA platform. After sequencing, 36 nucleotide changes were detected in the CDS of <it>eIF4E </it>and 26 in <it>eIF(iso)4E</it>. A total of 21 <it>eIF4E </it>haplotypes and 15 <it>eIF(iso)4E </it>haplotypes were identified. To evaluate the functional relevance of this variability, 31 possible eIF4E/eIF(iso)4E combinations were tested against <it>Potato virus Y</it>. The results showed that five new <it>eIF4E </it>variants (<it>pvr2¹⁰</it>, <it>pvr2¹¹</it>, <it>pvr2¹²</it>, <it>pvr2¹³</it>and <it>pvr2¹⁴</it>) were related to PVY-resistance responses.</p> <p>Conclusions</p> <p>EcoTILLING was optimised in different <it>Capsicum </it>species to detect allelic variants of target genes. This work is the first to use cDNA instead of genomic DNA in EcoTILLING. This approach avoids intronic sequence problems and reduces the number of reactions. A high level of polymorphism has been identified for initiation factors, showing the high genetic variability present in our collection and its potential use for other traits, such as genes related to biotic or abiotic stresses, quality or production. Moreover, the new <it>eIF4E </it>and <it>eIF(iso)4E </it>alleles are an excellent collection for searching for new resistance against other RNA viruses.</p

Implementation of a Virtual Assistant for the Academic Management of a University with the Use of Artificial Intelligence

Currently, private universities, as a result of the pandemic that the world is facing, are going through very delicate moments in several areas, both academic and financial. Academically, there are learning problems and these are directly related to the dropout rate, which brings financial problems. Added to this are the economic problems caused by the pandemic, where the rates of students who want to access a private education have dropped considerably. For this reason, it is necessary for all private universities to have support to improve their student income and avoid cuts in budgets and resources. However, the academic part represents a great effort to fulfill their academic activities, which are the priority, with attention on those interested in pursuing a training programs. To solve these problems, it is important to integrate technologies such as Chatbots, which use artificial intelligence in such a way that tasks such as providing information on an academic courses are addressed by them, reducing the administrative burden and improving the user experience. At the same time, this encourages people to be a part of the college

[El rey Enrique el Enfermo]

Según el Catálogo de autores teatrales del siglo XVII de Urzáiz, esta obra está erroneamente atribuida a Cañizares; se trata de una comedia escrita por Juan de Zabaleta, Antonio Martínez de Meneses, Pedro Rosete Niño, Sebastián de Villaviciosa, Jerónimo de Cáncer y Velasco y Agustín MoretoPrecede al tit. "Num. 120"Los datos de publicación constan en el colofónLa imprenta de la Calle de la Rua de Salamanca es la Imprenta de la Santa Cruz, de Domingo Casero. Según Gutiérrez del Caño, ejerce ca.: 1777-1785Sign.: A-D4Texto a dos col

[El rey Enrique el Enfermo]

Según Urzáiz, esta obra está erronemaente atribuida a Cañizares; se trata de una comedia escrita por Juan de Zabaleta, Antonio Martínez de Meneses, Peddro Rosete Niño, Sebastián de Villaviciosa, Jerónimo de Cáncer y Velasco y Agustín MoretoPrecede al tít. "N. 125"Autor tomado del "Catálogo de comedias sueltas conservadas en la Biblioteca de la Real Academia Española", 1010Datos de publicación tomados del colofónSign.: A-D4Texto a dos col