Incompatibilidade de enxertia em Prunus

A incompatibilidade de enxertia é um problema que, além de prejuízo econômico aos produtores, causa atraso no lançamento de novas cultivares-copa e portaenxertos, devido ao longo período de tempo necessário para os testes de compatibilidade. O objetivo desta revisão é fazer um apanhado das principais e mais relevantes pesquisas realizadas envolvendo o tema incompatibilidade de enxertia em espécies frutíferas, especialmente as do gênero Prunus. Incompatibilidade é um fenômeno extremamente complexo, que envolve interações anatômicas, fisiológicas, bioquímicas e moleculares entre a cultivar-copa e o portaenxerto. Sendo, por essa razão, um problema de difícil estudo. Porém, acredita-se que através de uma análise conjunta dos diversos mecanismos de incompatibilidade, se pode avançar mais rapidamente no entendimento deste fenômeno

To defend or to grow: Lessons from Arabidopsis C24

The emergence of Arabidopsis as a model species and the availability of genetic and genomic resources have resulted in the identification and detailed characterization of abiotic stress signalling pathways. However, this has led only to limited success in engineering abiotic stress tolerance in crops. This is because there needs to be a deeper understanding of how to combine resistances to a range of stresses with growth and productivity. The natural variation and genomic resources of Arabidopsis thaliana (Arabidopsis) are a great asset to understand the mechanisms of multiple stress tolerances. One natural variant in Arabidopsis is the accession C24, and here we provide an overview of the increasing research interest in this accession. C24 is highlighted as a source of tolerance for multiple abiotic and biotic stresses, and a key accession to understand the basis of basal immunity to infection, high water use efficiency, and water productivity. Multiple biochemical, physiological, and phenological mechanisms have been attributed to these traits in C24, and none of them constrains productivity. Based on the uniqueness of C24, we postulate that the use of variation derived from natural selection in undomesticated species provides opportunities to better understand how complex environmental stress tolerances and resource use efficiency are co-ordinated

Arabidopsis peptide methionine sulfoxide reductase2 prevents cellular oxidative damage in long nights

Peptide methionine sulfoxide reductase (PMSR) is a ubiquitous enzyme that repairs oxidatively damaged proteins. In Arabidopsis (Arabidopsis thaliana), a null mutation in PMSR2 (pmsr2-1), encoding a cytosolic isoform of the enzyme, exhibited reduced growth in short-day conditions. In wild-type plants, a diurnally regulated peak of total PMSR activity occurred at the end of the 16-h dark period that was absent in pmsr2-1 plants. This PMSR activity peak in the wild-type plant coincided with increased oxidative stress late in the dark period in the mutant. In pmsr2-1, the inability to repair proteins resulted in higher levels of their turnover, which in turn placed an increased burden on cellular metabolism. This caused increased respiration rates, leading to the observed higher levels of oxidative stress. In wild-type plants, the repair of damaged proteins by PMSR2 at the end of the night in a short-day diurnal cycle alleviates this potential burden on metabolism. Although PMSR2 is not absolutely required for viability of plants, the observation of increased damage to proteins in these long nights suggests the timing of expression of PMSR2 is an important adaptation for conservation of their resources

Variations in the activity of glutathione reductase and the cellular glutathione content in relation to sensitivity to methylviologen in Escherichia coli

International audienc

pGreen : a versatile and flexible binary Ti vector for Agrobacterium-mediated plant transformation

Binary Ti vectors are the plasmid vectors of choice in Agrobacterium-mediated plant transformation protocols. The pGreen series of binary Ti vectors are configured for ease-of-use and to meet the demands of a wide range of transformation procedures for many plant species. This plasmid system allows any arrangement of selectable marker and reporter gene at the right and left T-DNA borders without compromising the choice of restriction sites for cloning, since the pGreen cloning sites are based on the well-known pBluescript general vector plasmids. Its size and copy number in Escherichia coli offers increased efficiencies in routine in vitro recombination procedures. pGreen can replicate in Agrobacterium only if another plasmid, pSoup, is co-resident in the same strain. pSoup provides replication functions in trans for pGreen. The removal of RepA and Mob functions has enabled the size of pGreen to be kept to a minimum. Versions of pGreen have been used to transform several plant species with the same efficiencies as other binary Ti vectors. Information on the pGreen plasmid system is supplemented by an Internet site (http://www.pgreen.ac.uk) through which comprehensive information, protocols, order forms and lists of different pGreen marker gene permutations can be found

Light-dependent changes in glutathione redox state in different organelles in cd-treated arabidopsis leaves

1 página - Poster presentado en: Understanding plant responses to climate change: redox-based strategies. Universidad Internacional de Andalucía, Baeza, Jaén. 20-22 septiembre 2021.This study was co-funded by the Ministry of Science, Innovation and Universities, the European Regional Development Fund (MCIU/AEI/ERDF) grant PGC2018-098372-B100 and I-LINK1247 from CSIC

Integrating transcriptomic techniques and k-means clustering in metabolomics to identify markers of abiotic and biotic stress in Medicago truncatula

Nitrogen-fixing legumes are invaluable crops, but are sensitive to physical and biological stresses. Whilst drought and infection from the soil-borne pathogen Fusarium oxysporum have been studied individually, their combined effects have not been widely investigated