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Very long-chain fatty acids (VLCFAs) possess more than twenty carbon atoms and are the major components of seed storage oil, wax, and lipids. FAE (Fatty Acid Elongation) like genes take part in the biosynthesis of VLCFAs, growth regulation, and stress responses, and are further comprised of KCS (Ketoacyl-CoA synthase) and ELO (Elongation Defective Elongase) sub-gene families. The comparative genome-wide analysis and mode of evolution of KCS and ELO gene families have not been investigated in tetraploid Brassica carinata and its diploid progenitors. In this study, 53 KCS genes were identified in B. carinata compared to 32 and 33 KCS genes in B. nigra and B. oleracea respectively, which suggests that polyploidization might has impacted the fatty acid elongation process during Brassica evolution. Polyploidization has also increased the number of ELO genes in B. carinata (17) over its progenitors B. nigra (7) and B. oleracea (6). Based on comparative phylogenetics, KCS, and ELO proteins can be classified into eight and four major groups, respectively. The approximate date of divergence for duplicated KCS and ELO genes varied from 0.03 to 3.20 million years ago (MYA). Gene structure analysis indicated that the maximum number of genes were intron-less and remained conserved during evolution. The neutral type of selection seemed to be predominant in both KCS and ELO genes evolution. String-based protein-protein interaction analysis suggested that bZIP53, a transcription factor might be involved in the activation of transcription of ELO/KCS genes. The presence of biotic and abiotic stress-related cis-regulatory elements in the promoter region suggests that both KCS and ELO genes might also play their role in stress tolerance. The expression analysis of both gene family members reflect their preferential seed-specific expression, especially during the mature embryo development stage. Furthermore, some KCS and ELO genes were found to be specifically expressed under heat stress, phosphorus starvation, and Xanthomonas campestris infection. The current study provides a basis to understand the evolution of both KCS and ELO genes in fatty acid elongation and their role in stress tolerance. [ABSTRACT FROM AUTHOR]

Background: Disease-resistant cultivars are the best solution to get their maximum yield potential and avoid fungicide application. There is no doubt about the contribution, and use of R genes (resistance genes) in resistance development in plants, while S genes (susceptibility genes) also hold a strong position in pathogenesis by resistance repression, and their loss of function contributes to enhanced resistance. Hence, we attempted to knock out the function of the StERF3 gene in potatoes through CRISPR/Cas9-based genome editing and investigated the CRISPR/Cas9 approach as strategic control against late blight disease in potato plants. Methods and results: The StERF3 gene was edited in late blight susceptible cv. Lady Rosetta. Full allelic edited plants were identified through DnpI, and N1aIV mediated restriction digestion and then further analyzed through Indel Detection by Amplicon Analysis. Sequence analysis of targeted plants for indel identification showed full allelic editing. The detached leaf assay of full allelic edited plants demonstrated the role of the StERF3 gene in susceptibility to late blight in potatoes. In planta disease assay also showed reduced, slowed, and delayed disease progression in StERF3-loss-of-function mutants compared to wild-type (control) plants. Less fungal biomass was quantified in knockouts through Real-time qPCR that supported less susceptibility of edited plants to late blight. Besides, relatively high expression of pathogens-related genes, StPR1, and StNPR1, were also observed in StERF3-loss-of-function mutants compared to the corresponding control. Conclusion: The results showed the functional inhibition of StERF3 genes using the CRISPR/Cas9 approach. The functional knockouts (StERF3 gene-edited potato plants) revealed enhanced resistance against Phytophthora infestans, thereby demonstrating the best strategic control for late blight disease in potato plants. [ABSTRACT FROM AUTHOR]

We investigated the anti-phytopathogen potential of silver nanoparticles synthesized by the bioreduction of AgNO3 in Bacillus subtilis culture supernatant against Cercospora canescens, causing leaf spot disease in Vigna radiata (mungbean). The biosynthesized AgNPs were characterized using UV–visible spectroscopy that showed a broad Surface Plasmon resonance (SPR) peak at 410 nm, dynamic light scattering (DLS) measurement for size distribution and intensity, polydispersity index, and zeta potential for determining their stability. Atomic Force Microscopy determined that they were spherical with an average particle size of 8 nm. In vitro study and tripartite assay under greenhouse conditions were carried out to evaluate the nanoparticles application as a management strategy to control and/ protection from the Cercospora leaf spot disease in mungbean. The inhibitory effect of eight AgNPs concentrations was investigated for in vitro antifungal potential assessment; biosynthesized AgNPs were found to decrease the fungal growth and increase the mycelial inhibition. Their antagonistic effect was also recorded on conidial germination. The conidia under AgNPs exposure showed germination repression. The maximum mycelial inhibition (94.00 ± 0.5) was observed for 800 ppm at 96 h. The greenhouse experimentations revealed the antifungal efficiency of AgNPs against Cercospora Leaf spot disease in mungbean. The 800 ppm AgNPs concentration gave a statistically significant result (46.87 ± 3.74) and proved best in In planta experiment with maximum disease reduction. Cercospora leaf spot-induced biochemical alterations were recorded to be reversed towards normal levels after biosynthesized AgNPs application on challenged mungbean plants. Our data unravelled the potential of biosynthesized AgNPs against Cercospora canescens challenge in mungbean, pointing towards its application in plant disease management. [ABSTRACT FROM AUTHOR]

Using surface tension and fluorescence methods, the surface and solution properties of two cationic gemini surfactants {pentanediyl-1,5-bis(dimethylcetylammonium bromide) and hexanediyl-1,6-bis(dimethylcetylammonium bromide)} (referred to as 16- 5-16 and 16- 6-16) have been studied in the presence and absence of primary linear alkanols. Parameters studied include the critical micelle concentration (CMC), C20 (the surfactant concentration required to reduce the surface tension of the solvent by 20 mN·m −1), Гmax (maximum surface excess), and Amin (minimum surface area per molecule). These parameters indicate mixed micelle formation and, therefore, surfactant-additive interaction parameters in mixed micelles and mixed monolayers, as well as activity coefficients, were calculated. A synergistic effect was observed in all instances and was found to be correlated with the chain length of the alkanols. The CMC values of 16- s-16 ( s =  5, 6) decrease with increasing alkanol concentration and the extent of this effect follows the sequence: 1-octanol (C 8OH) > 1-heptanol (C 7OH) > hexan-1-ol (C 6OH) > 1-pentanol (C 5OH) > butanol (C 4OH). The micelle aggregation number ( Nagg) of mixed micelles has been obtained using the steady state fluorescence quenching method. The micropolarity of gemini/alkanol systems has been evaluated from the ratio of intensity of peaks ( I1/ I3) of the pyrene fluorescence emission spectra. Results are interpreted on the basis of the structure of mixed micelles and monolayers. [ABSTRACT FROM AUTHOR]