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Two species of Ceratosporella collected on leaf litter of Mohru Oak Quercus floribunda in Uttarakhand, India, are described herein and compared with closely allied species. They are Ceratosporella deviata and Ceratosporella cheiroidea. Among them, C. cheiroidea is newly recorded from India. Morphological descriptions, illustrations, and comments are provided for the aforementioned species. [ABSTRACT FROM AUTHOR]

In this study, we identified and characterize a plant pathogenic isolate, collected from naturally infested bean (Phaseolus vulgaris var. Anupama) seedlings presenting root rot symptoms from an agricultural land of the Prayagraj district, Uttar Pradesh, India. Based on morphological features, growth characteristics and the ITS sequencing‐based molecular data, the isolate was assumed very closed to the species of the Pythium genera. However, ITS sequencing data and the BLAST results for gene annotation clustered the identified isolate more closely to the Pythium catenulatum (p‐value e‐value), and therefore, confirmed as P. catenulatum. The pathogenicity assay confirmed the role of the isolate as a root rot causing pathogen. Furthermore, the isolate was tested for its growth under in‐vitro conditions against several environmental parameters including temperature, pH, salt, drought and metals. The Biolog FF MicroPlate method assessed the carbon utilization profile and reported the ability of the isolate in utilizing both carbohydrates and amino acids as a primary energy source. Moreover, in‐vitro colony growth inhibition assay performed with different agrochemicals (fungicides and insecticides) and the dyes determined their efficacy in suppressing the growth and development of the isolated pathogen. The dual culture assay of the isolate along with several fungal and bacterial strains confirmed the antagonistic potential of some tested microbes in delimiting the growth of the pathogen. Overall, the study provides a new sustainable, effective and eco‐friendly solution for controlling the root rot pathogen. [ABSTRACT FROM AUTHOR]

Plant growth‐promoting rhizobacteria (PGPR) are diverse groups of plant‐associated microorganisms, which can reduce the severity or incidence of disease during antagonism among bacteria and soil‐borne pathogens, as well as by influencing a systemic resistance to elicit defense response in host plants. An amalgamation of various strains of PGPR has improved the efficacy by enhancing the systemic resistance opposed to various pathogens affecting the crop. Many PGPR used with seed treatment causes structural improvement of the cell wall and physiological/biochemical changes leading to the synthesis of proteins, peptides, and chemicals occupied in plant defense mechanisms. The major determinants of PGPR‐mediated induced systemic resistance (ISR) are lipopolysaccharides, lipopeptides, siderophores, pyocyanin, antibiotics 2,4‐diacetylphoroglucinol, the volatile 2,3‐butanediol, N‐alkylated benzylamine, and iron‐regulated compounds. Many PGPR inoculants have been commercialized and these inoculants consequently aid in the improvement of crop growth yield and provide effective reinforcement to the crop from disease, whereas other inoculants are used as biofertilizers for native as well as crops growing at diverse extreme habitat and exhibit multifunctional plant growth‐promoting attributes. A number of applications of PGPR formulation are needed to maintain the resistance levels in crop plants. Several microarray‐based studies have been done to identify the genes, which are associated with PGPR‐induced systemic resistance. Identification of these genes associated with ISR‐mediating disease suppression and biochemical changes in the crop plant is one of the essential steps in understanding the disease resistance mechanisms in crops. Therefore, in this review, we discuss the PGPR‐mediated innovative methods, focusing on the mode of action of compounds authorized that may be significant in the development contributing to enhance plant growth, disease resistance, and serve as an efficient bioinoculants for sustainable agriculture. The review also highlights current research progress in this field with a special emphasis on challenges, limitations, and their environmental and economic advantages. [ABSTRACT FROM AUTHOR]

Postemergence damping‐off of chilli caused by Pythium spp. is a common and serious problem in large chilli growing areas of India under the moist conditions that generally prevails during the sowing period. Therefore, in order to better understand this disease, an isolate belonging to the genus Pythium (Pythiales) was isolated from the infected chilli (Capsicum annuum L.) plant root parts collected from the fields of Chandauli district, Uttar Pradesh, India. Based on the congruence of cultural, morphological, cardinal growth rate and the sequence data analysis, the isolate was identified as Pythium graminicola. The molecular phylogenetic analysis based on ITS‐rDNA sequences clustered the isolate with representative sequences for P. graminicola from GenBank in the Pythium clade. The isolate carbon utilization profiles were characterized using Biolog FF MicroPlate method. The results revealed that the isolate used a wide range of carbon sources, mainly carbohydrates, but also amino acids, suggesting the use of metabolic routes that include glycolysis/gluconeogenesis. Moreover, an in vitro colony growth inhibition assay was performed to determine the influence of chemical (fungicides) and biological (bacteria and fungi) antagonists over the pathogen using the poison plate and dual culture method, respectively. Overall, the results revealed that the presence of aggressive broad range biocontrol agents can be used as an effective environmentally friendly approach for management and control of damping‐off in production systems. The antagonist can serve as a bio‐efficient and eco‐friendly alternative to synthetic fungicides for the development of an effective integrated pest management (IPM) system and obtaining higher yields. [ABSTRACT FROM AUTHOR]