Synchronised regulation of disease resistance in primed finger millet plants against the blast disease

Formulation-based antagonistic endophyte Amycolatopsis sp. SND-1 triggers defense response in Vigna radiata (L.) R. Wilczek. (Mung bean) against Cercospora leaf spot disease

In the present work, Amycolatopsis sp. SND-1 (SND-1) was isolated from Cleome chellidonii Linn. (C. chellidonii) was performed as biocontrol and resistance elicitor in Vigna radiata (L.) R. Wilczek (mung bean) plants against Cercospora leaf spot causing pathogen Cercospora canescens (C. canescens). The SND-1 isolate showed 74% of inhibition against C. canescens in dual culture and GC-MS analysis revealed the presence of antifungal compounds. Molecular characterization through 16S rRNA showed that the isolated SND-1 belongs to Amycolatopsis sp. The in vitro plant growth trials exhibited production of indole acetic acid, gibberellic acid, cytokinin, ammonia, hydrogen cyanide, and siderophore and phosphate solubilization. In vivo study with talcum formulation of SND-1 revealed a significant increase in plant root length, shoots length, root and shoot fresh weight, and reduced the disease severity in treated mung bean plants. Triggering of resistance by SND-1 formulation was studied by histochemical depositions and biochemical defense enzymes that resulted in the acceleration in defense response in comparison with control plants. The bioactive endophytic Amycolatopsis sp. SND-1 enhanced the defense against C. canescens infection; hence, it can be used as a biological control agent in mung bean cultivars.

Integration of transcriptomic and proteomic analyses for finger millet [Eleusine coracana (L.) Gaertn.] in response to drought stress

Drought is one of the most significant abiotic stresses that affects the growth and productivity of crops worldwide. Finger millet [Eleusine coracana (L.) Gaertn.] is a C₄ crop with high nutritional value and drought tolerance. However, the drought stress tolerance genetic mechanism of finger millet is largely unknown. In this study, transcriptomic (RNA-seq) and proteomic (iTRAQ) technologies were combined to investigate the finger millet samples treated with drought at different stages to determine drought response mechanism. A total of 80,602 differentially expressed genes (DEGs) and 3,009 differentially expressed proteins (DEPs) were identified in the transcriptomic and proteomic levels, respectively. An integrated analysis, which combined transcriptome and proteome data, revealed the presence of 1,305 DEPs were matched with the corresponding DEGs (named associated DEGs-DEPs) when comparing the control to samples which were treated with 19 days of drought (N1-N2 comparison group), 1,093 DEGs-DEPs between control and samples which underwent rehydration treatment for 36 hours (N1-N3 comparison group) and 607 DEGs-DEPs between samples which were treated with drought for 19 days and samples which underwent rehydration treatment for 36 hours (N2-N3 comparison group). Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified 80 DEGs-DEPs in the N1-N2 comparison group, 49 DEGs-DEPs in the N1-N3 comparison group, and 59 DEGs-DEPs in the N2-N3 comparison group, which were associated with drought stress. The DEGs-DEPs which were drought tolerance-related were enriched in hydrolase activity, glycosyl bond formation, oxidoreductase activity, carbohydrate binding and biosynthesis of unsaturated fatty acids. Co-expression network analysis revealed two candidate DEGs-DEPs which were found to be centrally involved in drought stress response. These results suggested that the coordination of the DEGs-DEPs was essential to the enhanced drought tolerance response in the finger millet.