We have isolated an Arabidopsis thaliana gene that codes for a receptor related to antifungal pathogenesisrelated (PR) proteins. The PRSK gene codes for a predicted 665-amino acid polypeptide that comprises an extracellular domain related to the PR5 proteins, a central transmembranespanning domain, and an intracellular protein-serine/threonine kinase. The extracellular domain of PR5K (PR5-like receptor kinase) is most highly related to acidic PR5 proteins that accumulate in the extracellular spaces of plants challenged with pathogenic microorganisms. The kinase domain of PR5K is related to a family of protein-serine/threonine kinases that are involved in the expression of self-incompatibility and disease resistance. PR5K transcripts accumulate at low levels in all tissues examined, although particularly high levels are present in roots and inflorescence stems. Treatmentg that induce authentic PR5 proteins had no effect on the level of PR5K transcripts, suggesting that the receptor forms part of a preexisting surveillance system. When the kinase domain of PR5K was expressed in Escherichia coli, the resulting polypeptide underwent autophosphorylation, consistent with its predicted enzyme activity. These results are consistent with PRSK encoding a functional receptor kinase. Moreover, the structural similarity between the extracellular domain of PR5K and the antimicrobial PR5-proteins suggests a possible interaction with common or related microbial targets.Reversible protein phosphorylation is a major mechanism for the transduction and amplification of cellular signals in plants (1). Biochemical and molecular genetic evidence has implicated protein phosphorylation in processes as diverse as the cellular transduction of ethylene (2), the regulation of leaf and flower development (3), and the transduction of calciummediated responses (4).A number of studies have implicated protein phosphorylation in the expression of disease resistance and selfincompatibility (SI). Exposure of plant cells to elicitors of the defense response leads to the rapid phosphorylation of microsomal polypeptides (5, 6). Moreover, activation of the defense response is sensitive to inhibitors of protein kinases and can be simulated by inhibitors of phosphoprotein phosphatases (7-9). The recent identification of the Pto disease-resistance (R) gene product from tomato as a raf-like protein kinase (10) suggests a central role for protein phosphorylation in the perception and signaling of pathogenic signals. The cloning of genes encoding the S-locus receptor kinase (SRK) of Brassicaceae (11, 12) has similarly uncovered a key role for protein phosphorylation in the expression of sporophytic SI. Both SRK and the related, secreted S-locus glycoprotein (SLG) are required for SI (13)(14)(15) and are thought to act in concert in the perception and signaling of a polypeptide ligand yet to be identified (16).The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement...

We report here the development of transgenic tobacco plants with thaumatin gene of Thaumatococcus daniellii under the control of a strong constitutive promoter -CaMV 35S. Both polymerase chain reaction and genomic Southern analysis confirmed the integration of transgene. Transgenic plants exhibited enhanced resistance with delayed disease symptoms against fungal diseases caused by Pythium aphanidermatum and Rhizoctonia solani. The leaf extract from transgenic plants effectively inhibited the mycelial growth of these pathogenic fungi in vitro. The transgenic seeds exhibited higher germination percentage and seedling survival under salinity and PEG-mediated drought stress as compared to the untransformed controls. These observations suggest that thaumatin gene can confer tolerance to both fungal pathogens and abiotic stresses.

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Aim: The present study was undertaken to analyze genetic diversity among pearl millet genotypes based on drought linked morpho-physiological and microsatellite markers. Study Design: In the present investigation, 96 pearl millet germplasm lines were screened against drought using different morphological and physiological traits along with SSR markers. Place and Duration of the Study: The present study was conducted at College of Agriculture, Gwalior, Rajmata Vijayaraje Scindia Krishi Vishwa Vidyalaya, Gwalior, M.P., India during July 2019 to December, 2020. Methodology: The study was conducted to record different morphological and physiological traits related to drought tolerance and susceptibility. Thirty five microsatellite markers were also used in laboratory to analyze the variability among pearl millet genotypes under study. Results: Pearl millet genotypes were grouped according to their morpho-physiological characteristics. Among 35 SSR markers, twenty-two were successfully amplified across all germplasm lines and seven SSR markers were found to be polymorphic and fifteen markers were monomorphic. All seven polymorphic SSR markers were used consequently for amplification of all the 96 germplasm lines. The range of PIC value was 0.0939 to 0.2980 with the average of 0.2274. The highest PIC value was recorded for the markers Xibmsp26 and Xibmsp29 (0.2980), followed by Xibmsp03 (0.2392), Xibmsp29 (0.2392), Xibmsp06 (0.2289) and Xibmsp07 (0.1948) while the lowest for the marker Xibmsp01 (0.0939). The range of major allele frequency value was 0.7604 to 0.9479 with the average of 0.8363. The range of genetic diversity value was 0.0987 to 0.3644 with the average of 0.2665. Conclusions: According to the morpho-physiological data a total of 22 pearl millet genotypes were found to be grouped distantly from rest of the genotypes. These genotypes had shown their drought tolerance bahaviour however, rests of the genotypes were found to be susceptible against drought.

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