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Introduction: Biological control holds great promise for environmentally friendly and sustainable management of the phytopathogens. The multi-function features of plant growth-promoting rhizobacteria (PGPR) enable to protect the plants from disease infections by replacing the chemical inputs. The interaction between the plant root exudates and the microbes stimulates the production of secondary metabolism and enzymes and induces systemic resistance in the plants., Aim: The aim was to identify the potential PGPR which would show an antagonistic effect against basmati rice fungal and bacterial diseases., Methods: In the study, native originating microbes have been isolated, characterized using 16S rRNA sequencing, and used as potential antagonistic microbial isolates against diseases of rice plants., Results: Rhizobacteria isolated from rhizosphere, endo-rhizosphere, and bulk soil samples of Basmati 370 exhibited promising inhibitory activity against rice pathogens. Molecular characterization of bacterial isolates based on 16S rRNA sequencing classified the bacterial isolates into different genera such as Bacillus, Pseudomonas, Streptomyces, Exiguobacterium, Aeromonas, Chryseobacterium, Enterobacter, and Stenotrophomonas. PGPRs exhibited biocontrol activities against various rice diseases like bacterial leaf blight, leaf blast, brown spot, and sheath blight and boost the plant growth traits., Conclusion: In the study, the potentially identified PGPRs isolates could be used as efficient bioinoculants as bio-fertilizers and biocontrol agents for sustainable rice crop production.

A backstepping controller augmented with a state predictor is proposed to control a quadrotor over a network subjected to both state and input time delay. The state predictor predicts the future values of the states by taking the measured delayed states as input. A backstepping control law is further designed based on these predicted states. It is shown with the aid of the Lyapunov-Razumikhin theorem that the error dynamics of the predictor is asymptotically stable. The cascade of state predictor and backstepping controller makes the tracking error dynamics of the quadrotor asymptotically stable. Simulation results are presented to validate the proposed approach., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 ISA. Published by Elsevier Ltd. All rights reserved.)

The inhibition of Plasmodium cytosolic phenylalanine tRNA-synthetase (cFRS) by a novel series of bicyclic azetidines has shown the potential to prevent malaria transmission, provide prophylaxis, and offer single-dose cure in animal models of malaria. To date, however, the molecular basis of Plasmodium cFRS inhibition by bicyclic azetidines has remained unknown. Here, we present structural and biochemical evidence that bicyclic azetidines are competitive inhibitors of L-Phe, one of three substrates required for the cFRS-catalyzed aminoacylation reaction that underpins protein synthesis in the parasite. Critically, our co-crystal structure of a PvcFRS-BRD1389 complex shows that the bicyclic azetidine ligand binds to two distinct sub-sites within the PvcFRS catalytic site. The ligand occupies the L-Phe site along with an auxiliary cavity and traverses past the ATP binding site. Given that BRD1389 recognition residues are conserved amongst apicomplexan FRSs, this work lays a structural framework for the development of drugs against both Plasmodium and related apicomplexans.

Panicle traits are the most important agronomic characters which directly relate to yield in rice. Panicle length (PL) being one of the major components of rice panicle structure is controlled by quantitative trait loci (QTLs). In our research, conducted at Research Farm of SKUAST-J, crosses of parental lines K343 and DHMAS were made for generating F 2 mapping population, which were then transplanted into the field using augmented design-I. The F 2 population was used for phenotypic evaluation, development of linkage map and identification of QTLs on the chromosomes by using SSR markers. A total of 450 SSR markers were used for screening both the parents of which 53 highly polymorphic markers were selected and used for genotyping of 233 genotypes of F 2 population. Linkage map was generated using MAPMAKER/EXP3.0 software, seven linkage groups were found distributed on 11 chromosomes of rice. QTLs were detected using QTL Cartographer (v2.5) software. Based on 1000 permutation tests, a logarithm of odds (LOD) threshold value 2.0 and 3.0 was set. Composite interval mapping was used to map QTLs in populations derived from bi-parental crosses. The phenotypic data, genotypic data and the genetic linkage map generated identified total three QTLs of which one was identified for PL qPL2, located at 85.01 cM position with 2.1 LOD value and in between the marker intervals RM324-RM208, this QTL explained the phenotype variation by 4.36%. The other two QTLs were identified for spikelet density (SD) qSD3.1 and qSD3.2, located at 28.91 and 39.51 cM, respectively, both with a flanking marker RM6832 on chromosome 3. The LOD value and phenotypic variation explained for qSD3.1 and qSD3.2 was 3.00 and 3.25; 9.70 and 12.34% respectively. The reported QTLs identified in the study suggested a less diversity in the parents used and also the rejection of not so useful markers from the used set of markers for PL and SD.

Antimalarial drugs have thus far been chiefly derived from two sources-natural products and synthetic drug-like compounds. Here we investigate whether antimalarial agents with novel mechanisms of action could be discovered using a diverse collection of synthetic compounds that have three-dimensional features reminiscent of natural products and are underrepresented in typical screening collections. We report the identification of such compounds with both previously reported and undescribed mechanisms of action, including a series of bicyclic azetidines that inhibit a new antimalarial target, phenylalanyl-tRNA synthetase. These molecules are curative in mice at a single, low dose and show activity against all parasite life stages in multiple in vivo efficacy models. Our findings identify bicyclic azetidines with the potential to both cure and prevent transmission of the disease as well as protect at-risk populations with a single oral dose, highlighting the strength of diversity-oriented synthesis in revealing promising therapeutic targets.