Association analysis in chia (Salvia hispanica L.)

The present study was carried out in a set of germplasm accessions for yield related traits in Chia. Results of the correlation coefficient revealed a highly significant and positive effect of the number of primary branches, harvest index and oil content on seed yield per plant on both genotypic and phenotypic levels, while plant height had a positive significant correlation with seed yield only at the genotypic level. Through analysis of path coefficients, the positive and significant direct effect of harvest index on genotypic as well as phenotypic levels was inferred, whilst days to 50% flowering and plant height illustrated positive direct effects on seed yield per plant only at the genotypic level. Moderate direct and positive effects of days to maturity at the genotypic level along with the number of primary branches at the phenotypic level were observed on seed yield per plant. The study revealed that harvesting index, days to 50% flowering and fruiting branches could be used as selection criteria traits, which will be very useful in future breeding programmes to enhance yield in Chia

Advancement in the Breeding, Biotechnological and Genomic Tools towards Development of Durable Genetic Resistance against the Rice Blast Disease

Rice production needs to be sustained in the coming decades, as the changeable climatic conditions are becoming more conducive to disease outbreaks. The majority of rice diseases cause enormous economic damage and yield instability. Among them, rice blast caused by Magnaportheoryzae is a serious fungal disease and is considered one of the major threats to world rice production. This pathogen can infect the above-ground tissues of rice plants at any growth stage and causes complete crop failure under favorable conditions. Therefore, management of blast disease is essentially required to sustain global food production. When looking at the drawback of chemical management strategy, the development of durable, resistant varieties is one of the most sustainable, economic, and environment-friendly approaches to counter the outbreaks of rice blasts. Interestingly, several blast-resistant rice cultivars have been developed with the help of breeding and biotechnological methods. In addition, 146 R genes have been identified, and 37 among them have been molecularly characterized to date. Further, more than 500 loci have been identified for blast resistance which enhances the resources for developing blast resistance through marker-assisted selection (MAS), marker-assisted backcross breeding (MABB), and genome editing tools. Apart from these, a better understanding of rice blast pathogens, the infection process of the pathogen, and the genetics of the immune response of the host plant are very important for the effective management of the blast disease. Further, high throughput phenotyping and disease screening protocols have played significant roles in easy comprehension of the mechanism of disease spread. The present review critically emphasizes the pathogenesis, pathogenomics, screening techniques, traditional and molecular breeding approaches, and transgenic and genome editing tools to develop a broad spectrum and durable resistance against blast disease in rice. The updated and comprehensive information presented in this review would be definitely helpful for the researchers, breeders, and students in the planning and execution of a resistance breeding program in rice against this pathogen