Responses of sorghum to cold stress: A review focused on molecular breeding.

Climate change has led to the search for strategies to acclimatize plants to various abiotic stressors to ensure the production and quality of crops of commercial interest. Sorghum is the fifth most important cereal crop, providing several uses including human food, animal feed, bioenergy, or industrial applications. The crop has an excellent adaptation potential to different types of abiotic stresses, such as drought, high salinity, and high temperatures. However, it is susceptible to low temperatures compared with other monocotyledonous species. Here, we have reviewed and discussed some of the research results and advances that focused on the physiological, metabolic, and molecular mechanisms that determine sorghum cold tolerance to improve our understanding of the nature of such trait. Questions and opportunities for a comprehensive approach to clarify sorghum cold tolerance or susceptibility are also discussed.

Isolation and Detection Methods of Plant miRNAs.

Small RNAs (sRNAs) are RNAs of low abundance in organisms. Among sRNAs, miRNAs are included and represent approximately 10% of the total number of sRNAs. The isolation of sRNAs is critical for miRNA detection and analysis. The precipitation of low-molecular-weight (LMW) RNAs from total RNA extracts has allowed enrichment of sRNAs. Here, we describe a simple method to isolate sRNAs from different plant species. The main advantage of this method is that it does not need first an extraction of total RNA and it is not based on TRIzol® reagent. This method has been successfully used for miRNA analyses by Northern blot assay and RT-qPCR (these techniques are as well described in this chapter), as well as sRNA library preparation.