Potassium fertilization in relation to downy mildew disease incidence in grape leaves

Influence of different sources of potassium and their method of application was studied on incidence of downy mildew infection in grape leaves of 'Sharad Seedless' (syn: 'Kishmish Chorni'). The total phenolic content and individual phenolic acids were analysed from healthy and downy mildew infected leaves of 'Sharad Seedless' and the degree of downy mildew infection was well correlated with potassium content in the petioles. Different sources and method of potassium application had significant effect on Phenylalanine ammonia-lyase (PAL) enzyme activity and preformed phenols in healthy vines. Significant increase in PAL enzyme activity, total phenols and individual phenolic acids was registered with increase in disease severity. Magnitude of percent change in PAL enzyme activity and total phenolic content was highest in vines with maximum disease infection. Among the phenolic acids, o-Coumaric acid, p-Coumaric acid have a definite role in disease resistance. We could also observe the variation in disease severity in vines which received different sources of potassium which was supplied in different quantities whether through soil and/or through fertigation

Inheritance and Allelic Relationship among Downy Mildew Resistance Genes in Pearl Millet

Pearl millet downy mildew (DM), caused by Sclerospora graminicola is of serious economic concern to pearl millet farmers in the major crop growing areas of the world. To study the inheritance and allelic relationship among genes governing resistance to this disease, three DM resistant pearl millet lines (834B, IP 18294-P1 and IP 18298-P1) and one susceptible line (81B) were selected on the basis of disease reaction under greenhouse conditions against two isolates of S. graminicola (Sg 526-1 and Sg 542-1). Three resistant parents were crossed with the susceptible parent to generate F1s, F2s and backcrosses BC1P1 (susceptible parent × F1) and BC1P2 (resistant parent × F1) for inheritance study. To carry out test for allelism, the three resistant parents were crossed with each other to generate F1s and F2s. The different generations of these crosses were screened for disease reaction against two isolates Sg 526-1 and Sg 542-1 by artificial inoculation under greenhouse conditions. The segregation pattern of resistance in the F2s, and corresponding backcross generations revealed that resistance to DM is controlled by a single dominant gene in 834B and IP 18294-P1, and by two dominant genes in IP 18298-P1. Test for allelism inferred that single dominant gene for resistance in 834B is non-allelic to that governs resistance in IP 18294-1; whereas one of the two dominant genes for DM resistance in IP 18298-P1 against the test isolates is allelic to gene for DM resistance in 834B and second gene is allelic to the resistance gene present in IP 18294-P1

Identification of genes controlling compatible and incompatible reactions of pearl millet (Pennisetum glaucum) against blast (Magnaporthe grisea) pathogen through RNA-Seq

Blast [Magnaporthe grisea (Herbert) Barr] is an economically important disease in Asian pearl millet production ecologies. The recurrent occurrence of blast in the past one decade has caused enormous strain on grain and forage production. Identification of resistance genes is an important step to develop durable varieties. The present study is the first attempt to use RNA-Seq to investigate the transcript dynamics in a pearl millet inbred ICMB 93333, which had a unique differential reaction to two isolates—Pg 45 (avirulent) and Pg 174 (virulent) of M. grisea. The inbred was inoculated by both isolates and samples taken at six different time intervals for genome-wide RNA-Seq experiment. The transcriptome results revealed the differential expression of more than 2,300 genes. The time-specific comparison showed activation or repression of specific genes in various pathways. Genes and transcriptions factors related to pathogenesis-related proteins, reactive oxygen species generating and its scavenging genes, cell wall defense, primary and secondary metabolic pathways, and signaling pathways were identified by comparing the host-plant compatible and incompatible interactions. The genes identified from this experiment could be useful to understand the host-plant resistance and design novel strategies to manage blast disease in pearl millet

Inheritance and allelic relationship among gene(s) for blast resistance in pearl millet [Pennisetum glaucum (L.) R. Br.]

Six blast‐resistant pearl millet genotypes, ICMB 93333, ICMB 97222, ICMR 06444, ICMR 06222, ICMR 11003 and IP 21187‐P1, were crossed with two susceptible genotypes, ICMB 95444 and ICMB 89111 to generate F1s, F2s and backcrosses, BC1P1 (susceptible parent × F1) and BC1P2 (resistant parent × F1) for inheritance study. The resistant genotypes were crossed among themselves in half diallel to generate F1s and F2s for test of allelism. The F1, F2 and backcross generations, and their parents were screened in a glasshouse against Magnaporthe grisea isolates Pg 45 and Pg 53. The reaction of the F1s, segregation pattern of F2s and BC1P1 derived from crosses involving two susceptible parents and six resistant parents revealed the presence of single dominant gene governing resistance in the resistant genotypes. No segregation for blast reaction was observed in the F2s derived from the crosses of resistant × resistant parents. The resistance reaction of these F2s indicated that single dominant gene conferring resistance in the six genotypes is allelic, that is same gene imparts blast resistance in these genotypes to M. grisea isolates

Ontology Mapping Techniques for Semantic Information Integration - A Literature Survey

The widespread adoption of the semantic web and information technologies has led to the development of ontologies to represent domain concepts in a very specific, independent and formal way. However, the proliferation of these ontologies now pose a different kind of problem in terms of managing and reusing ontologies effectively. The heterogeneity in the structure, content, representation, and purpose of the ontologies make it difficult to find appropriate ontologies for specific tasks. Similar ontologies with overlapping content and coverage can be integrated to begin to address this issue. Thus, it is worthwhile to merge some of the ontologies in a particular domain into a more general ontology with a common representation and clearly articulated semantic information. In order to make progress in developing a scalable approach for integrating ontologies, one needs to analyze and understand the existing approaches so that the gaps and the limitations can be clearly explicated and then develop approaches to mitigate these problems. A clear understanding of the status-quo will go a long way in developing a robust approach for mapping ontologies and integrating the semantic information. Thus, the aim of this research is to survey the existing literature and develop an understanding of the approaches used for extracting information from ontologies, identifying similar content, and integrating the semantic information. The existing mapping techniques are briefly summarized below. A) Structure based technique – the structure of entities found in ontologies can be compared, in addition to comparing their names or identifiers. This comparison can be on the internal structure of an entity, i.e., besides its name and annotations, its properties or, in the case of OWL ontologies, the properties which take their values in a datatype, or the comparison of the entity with other entities to which it is related. B) Instance based technique – this method determines the similarity between concepts of different ontologies by examining the extensional information of concepts that is the instance data. C) Semantic based technique – semantic based techniques find the semantic relations between ontologies and making corresponding mapping rules first, and then integrating all independent ontologies into a whole to be operated. Semantic based methodology uses semantics or the science of meaning in language, to produce highly relevant search results. D) Terminological based technique – some terminological methods compare strings. They can be applied to the name, the label or the comments of entities in order to find those which are similar. This can be used for comparing class names and/or URIs. Ontology mapping is needed to promote knowledge sharing and integrating semantics in an environment with different underlying ontologies. For given two ontologies, A and B, mapping one ontology with another means that for each concept in ontology A, finding the same or similar semantics in ontology B, and vice versa. The various ontology mapping methods and ontology integration techniques applied in different domain ontologies need to be compared based on various parameters such as input, output, sources of knowledge, algorithms and methods used, evaluation result etc. In this research, we focus on understanding the different levels of ontology mapping, ontology merging, aligning and integrating into a single ontology for the same domain. Different techniques have been used to map the different ontologies of same domain and we focus on how the semantic information is integrated using mapping techniques. Our future work includes additional literature survey and building a tool for mapping ontologies and developing an architecture for integrating into a target ontology using temporal information

NORMATIVE NASALANCE VALUES ACROSS STIMULI AND GENDER IN MALAYALAM SPEAKING INDIVIDUALS

Nasality is the common problem in subjects with repaired / unrepaired cleft palate, which affects the speech intelligibility. Nasal resonance is not only seen in disordered speech, even normal speech also consist some amount of nasality. Example: Among the Indian languages, Malayalam has got more nasal resonance than any other languages. Nasality can be assessed by subjective as well as objective methods. Perceptual judgment of nasality is done using various rating scales. These rating scales have used different rating points ranging from five point scale to nine point scales. The judges for these rating scales were from trained speech pathologists to clients themselves. Since this is a subjective task, standard data / normative data cannot be established due to many disadvantages associated with this method. Hence, standard objective methods are essential to assess the velopharyngeal dysfunction and to provide guidelines for suitable rehabilitation method.

Fertility and Mating Type Frequency in Indian Isolates of Sclerospora graminicola, the Downy Mildew Pathogen of Pearl Millet

Sclerospora graminicola, the downy mildew pathogen of pearl millet, is an oomycetous obligate parasite which reproduces by both sexual and asexual means. Fertility and mating type frequencies were studied in 70 single-zoospore isolates (SZIs) obtained from seven representative oo-sporic isolates (Sg 021, Sg 048, Sg 110, Sg 139, Sg 149, Sg 152, and Sg 153) of S. graminicola collected from major pearl millet-growing states of India. Of the 70 SZIs tested for fertility according to oospore production potential, 62 were self-sterile and 8 were self-fertile, indicating the low occurrence of homothallism in the S. graminicola populations. The sexual mating type test of the 70 SZIs, conducted by pairing each isolate with the two standard mating type tester isolates PT2 (Mat A) and PT 3 (Mat B), revealed 28 (40.0%) isolates of Mat A, 33 (47.14%) of Mat B, 8 (11.43%) of both Mat A and Mat B, and 1 (1.43%) as unknown. The frequencies of Mat A and Mat B were in approximately equal proportions among the isolates tested, except in three parental isolates. Implications of these results in understanding the dynamic genetic structure of S. graminicola population and potential for evolution of new virulence in the pathogen are discussed

Inheritance of avirulence in Sclerospora graminicola, the pearl millet downy mildew pathogen

The inheritance of avirulence in S. graminicola was studied by hybridizing the isolates Sg 139-4 (Mat A), highly virulent, and Sg 110-9 (Mat B), avirulent, on a pearl millet (Pennisetum glaucum) genotype IP 18292 containing a downy mildew resistance gene Rsg1. Pot-grown seedlings of IP 18292 were inoculated with sporangial inocula generated from sexual spores (oospore) of the parental isolates and their F1, F2, BC1 and BC2 progenies and incubated at 25±2°C and >90% relative humidity in a greenhouse. Downy mildew incidence was recorded two weeks after inoculation. Avirulence was dominant over virulence and a single gene pair (AA/Aa) controlled avirulence in isolate Sg 110-9 to a corresponding resistance gene Rsg1 in IP 18292. The pattern of segregation of virulence:avirulence suggested the presence of a gene-for-gene interaction between S. graminicola and P. glaucum

In vitro studies in Sauropus androgynous (L.) Merr.

Plant regeneration studies were carried out on Sauropus androgynous to standardize a protocol for high frequency plant regeneration. Nodal segments, shoot tip and leaves were used as explants which were obtained from the plants raised in polyhouse. Callus formation was observed on MS and L 2 medium supplemented with different concentrations (1-6 μM) of various auxins (NAA, 2,4-D, IAA and IBA). Direct single shoot with roots were obtained from shoot tip explants on MS & L 2 media supplemented with AS and multiple shoots were obtained from nodal explants on MS and L 2 media supplemented with BAP (1-6 μM). Leaf explants gave multiple shoots on MS media supplemented with BAP (13.20μM) + IAA (5.71 μM) and BAP (8.87 μM) + NAA (5.37 μM). Individual shoots were inoculated on 1/2 MS and 1/2 L 2 medium supplemented with different concentrations of auxins (NAA, 2,4-D, IAA and IBA) for rooting. Plantlets were able to regenerate within three to four months and were transferred to plastic pots for hardening

Rock-water interaction and chemical quality analysis of groundwater in hard rock terrain of Chamrajanagara district, Karnataka, India using geoinformatics

Groundwater is one of the main natural resources having its application in various fields which affects its quantity. Groundwater pollution occurs when used water is returned to the hydrological cycle. The present study aims to assess the spatial variations of groundwater quality parameters in Southern tip of Karnataka using Geoinformatics technique. Efforts have been made to evaluate a total number of 46 representative groundwater samples (C1 to C46) from different parts of the study area during pre-monsoon period (April-May 2005) to assess its parameters such as F- , NO3-, CO3-, Cl- , Ca2+, Mg2+, Na+ , SO4 2-, Fe, K+ , pH and EC. Groundwater quality is found to be more controlled by rock-water interaction and residence time of water in aquifers and affected more by anthropogenic factors at many locations. Each Land Use/Land Cover (LU/LC) patterns and major lineaments are mapped and digitized using SoI topomap of 1:50,000 scale and IRS-1D, PAN+LISS-III satellite data through GIS softwares. Wide applications of chemicals, pesticides, fertilizers, herbicides in large agricultural and vegetative lands; mining activities are the major factors that are contaminating the soil and leaching through seepage, fractures, faults and joints (lineaments) into the groundwater. The study reveals the potentiality of Geoinformatics application in preparation of more consistent and accurate baseline information predicting the groundwater quality in Precambrian hard rock terrain of the study area