Genetic, epigenetic, genomic and microbial approaches to enhance salt tolerance of plants: A comprehensive review

Globally, soil salinity has been on the rise owing to various factors that are both human and environmental. The abiotic stress caused by soil salinity has become one of the most damaging abiotic stresses faced by crop plants, resulting in significant yield losses. Salt stress induces physiological and morphological modifications in plants as a result of significant changes in gene expression patterns and signal transduction cascades. In this comprehensive review, with a major focus on recent advances in the field of plant molecular biology, we discuss several approaches to enhance salinity tolerance in plants comprising various classical and advanced genetic and genetic engineering approaches, genomics and genome editing technologies, and plant growth-promoting rhizobacteria (PGPR)-based approaches. Furthermore, based on recent advances in the field of epigenetics, we propose novel approaches to create and exploit heritable genome-wide epigenetic variation in crop plants to enhance salinity tolerance. Specifically, we describe the concepts and the underlying principles of epigenetic recombinant inbred lines (epiRILs) and other epigenetic variants and methods to generate them. The proposed epigenetic approaches also have the potential to create additional genetic variation by modulating meiotic crossover frequency

Marker-Assisted Selection for Biotic Stress Resistance in Peanut

Marker-assisted selection (MAS) in peanut has lagged behind other major crops. This is due in good part to the genetic bottleneck that occurred at tetraploidization, resulting in a limited amount of molecular variability detectable among accessions of the cultivated species. However, marker maps have been developed from wild species, and, to an increasing extent, the cultivated species using new marker types. It is expected that, with the increase in number of simple sequence repeat (SSR) markers and development of single nucleotide polymorphism (SNP)-based markers, there will be greater use of MAS in both interspecific and cultivated accession crosses. MAS has already proven itself to be useful in developing cultivars possessing resistance to the root-knot nematode, and is being used for selection for resistance to late leaf spot and rust, as well as for the high-oleic-acid trait

Influência de diferentes teores de sólidos insolúveis suspensos nas características reológicas de sucos de abacaxi naturais e despectinizados Influence of different contents of insoluble suspended solidS on rheological characteristics of natural and despectinized pineapple juice

Estudou-se, neste trabalho, a influência dos sólidos insolúveis suspensos nas características reológicas de sucos de abacaxi in natura e sucos tratados com enzima pectinolítica. Cada um dos dois tipos de suco foi estudado através de seis frações, divididas em quatro peneiradas, uma centrifugada e uma integral, representando seis teores de sólidos insolúveis suspensos. Os dados reométricos foram coletados através de um reômetro Haake rotovisco e os dados experimentais ajustados pelo modelo de Mizrahi-Berk. Das seis frações in natura, quatro apresentaram comportamento pseudoplástico, uma caracterizou-se como newtoniana e outra como dilatante enquanto das seis frações tratadas enzimaticamente cinco apresentaram comportamento pseudoplástico e uma caracterizou-se como newtoniana. O teor de sólidos insolúveis suspensos mostrou-se o principal fator responsável pelo comportamento reológico dos sucos de abacaxi naturais e despectinizados.<br>The influence of insoluble suspended solid contents in rheological characteristics of pineapple juice, both natural and treated with pectinolytic enzymes, was studied. Each type of juice was examined by six fractions, divided into four sievings, one centrifuged and the others whole, representing six contents of insoluble suspended solids. The rheometric data were collected by means of Haake rotovisco rheometer and the experimental data were adjusted by the Mizrahi-Berk model. In the natural material four fractions showed pseudoplastic behaviour, one characterized as newtonian and the others as dilatant, whereas in the enzyme treated material, five fractions presented pseudoplastic behaviour and one was characterized as newtonian. The insoluble suspended solid content was found to be the principal factor responsible for this rheological behaviour of natural and despectinized pineapple juices