Seed Pathology and Plant Quarantine in India     

S.P. Raychaudhuri    D. Kumar  R. Nath 《EPPO Bulletin》1976,6(5):439-444

The present situation regarding problems and achievements in seed pathology and domestic and international quarantine in India is described. Emphasis is placed upon the need for resolving present inadequacies in this country's quarantine legislation and for international alignment in seed health testing methods, in addition to a general information exchange on plant pathogens.  相似文献   

Use of next‐generation sequencing for the identification and characterization of Maize chlorotic mottle virus and Sugarcane mosaic virus causing maize lethal necrosis in Kenya     

I. P. Adams  D. W. Miano  Z. M. Kinyua  A. Wangai  E. Kimani  N. Phiri  R. Reeder  V. Harju  R. Glover  U. Hany  R. Souza‐Richards  P. Deb Nath  T. Nixon  A. Fox  A. Barnes  J. Smith  A. Skelton  R. Thwaites  R. Mumford  N. Boonham 《Plant pathology》2013,62(4):741-749

The diagnosis of novel unidentified viral plant diseases can be problematic, as the conventional methods such as real‐time PCR or ELISA may be too specific to a particular species or even strain of a virus, whilst alternatives such as electron microscopy (EM) or sap inoculation of indicator species do not usually give species level diagnosis. Next‐generation sequencing (NGS) offers an alternative solution where sequence is generated in a non‐specific fashion and identification is based on similarity searching against GenBank. The conventional and NGS techniques were applied to a damaging and apparently new disease of maize, which was first identified in Kenya in 2011. ELISA and TEM provided negative results, whilst inoculation of other cereal species identified the presence of an unidentified sap transmissible virus. RNA was purified from material showing symptoms and sequenced using a Roche 454 GS‐FLX+. Database searching of the resulting sequence identified the presence of Maize chlorotic mottle virus and Sugarcane mosaic virus, a combination previously reported to cause maize lethal necrosis disease. Over 90% of both viral genome sequences were obtained, allowing strain characterization and the development of specific real‐time PCR assays which were used to confirm the presence of the virus in material with symptoms from six different fields in two different regions of Kenya. The availability of these assays should aid the assessment of the disease and may be used for routine diagnosis. The work shows that next‐generation sequencing is a valuable investigational technique for rapidly identifying potential disease‐causing agents such as viruses.  相似文献   

A novel pathovar of Xanthomonas axonopodis causes gumming of Guggal (Commiphora wightii)     

Jatindra Nath Samanta  Kunal Mandal  Satyabrata Maiti 《European journal of plant pathology / European Foundation for Plant Pathology》2013,135(1):115-125

Guggal (Commiphora wightii (Arnott) Bhandari comb. nov.) is a small tree which is tapped for medicinally important oleo?Cgum?Cresin. Naturally infected plant oozes oleo?Cgum?Cresin from its trunk and primary branches. However, in either case, the plant dies slowly after oozing. A bacterium was established to be responsible for these phenomena. Four isolates of this bacterium were characterised by biochemical tests, Biolog GN2 microplate reaction, rDNA sequencing, which suggested that the pathogen belonged to the genus Xanthomonas. However, phylogenetic analysis based on chaperone protein (dnaK) gene, TonB?Cdependent receptor (fyuA) gene, DNA gyrase B (gyrB) gene and RNA polymerase sigma factor (rpoD) gene sequences placed it as a member of X. axonopodis 9.2 rep?CPCR/DNA?CDNA homology cluster close to X. perforans, X. alfalfae and X. euvesicatoria. Further elucidation of phylogenetic position of the test strains was achieved from a gyrB based tree considering sequences from 71 representative strains. Test strains were confirmed to be members of X. axonopodis. These had very narrow infectivity limited to Commiphora spp. Hence, we propose a novel pathovar, X. axonopodis pv. commiphoreae pv. nov. as the cause of gum oozing in guggal. Pathotype is DXA 01 = CFBP 7580 = LMG 26789.  相似文献   

Activin receptor type IIB in rohu (Labeo rohita): molecular characterization,tissue distribution and immunohistochemical localization during different stages of gonadal maturation     

Patnaik  Siddhi  Sahoo  Lakshman  Mohanty  Mausumee  Bit  Amrita  Meher  Prem Kumar  Das  Sachidananda  Jayasankar  Pallipuram  Saha  Jatindra Nath  Das  Paramananda 《Fish physiology and biochemistry》2021,47(5):1353-1367

Fish Physiology and Biochemistry - Activin receptor type IIB (ActRIIB) is a transmembrane serine/threonine kinase receptor which plays a pivotal role in regulating the reproduction in vertebrates...  相似文献   

Genetic divergence among a non-restorer collection of sorghum (Sorghum bicolor (L.) Moench) and its relationship with heterosis     

Bhola Nath  Abbas O. Omran  L. R. House 《Euphytica》1985,34(2):441-447

Summary A genetic diversity analysis in a collection of 171 non-restorer lines of sorghum (Sorghum bicolor (L.) Moench) using D² technique and canonical variate analysis indicated that considerable variation in grain yield has been added to the collection by the addition of lines derived from random mating populations. The efficiency of D² and canonical variate techniques in distinguishing extremely diverse genotypes was confirmed. However, the two techniques showed weak correspondence in their clusters. The F₁ hybrids of 15 diverse lines exhibited no relationship between heterosis or per se performance of crosses and diversity in their parents. Therefore, traditional plant breeding methods are being advocated.Approved by ICRISAT as Journal Article no. 435.  相似文献   

Pseudocercospora griseola,the causal agent of common bean angular leaf spot: Strain characterization and sensitivity to fungicides     

Samira Santiago Librelon  Fernanda Aparecida Castro Pereira  Paula Furtado de Pádua  Nathália Bottrel Maia Pereira  Luanna de Barros Wanderley Gomes  Rafael Pereira  Lucas Fidelis Pereira  Edson Ampélio Pozza  Elaine Aparecida de Souza 《Plant pathology》2022,71(6):1431-1439

Angular leaf spot (ALS), an important disease of common bean (Phaseolus vulgaris), is caused by the fungus Pseudocercospora griseola. This pathogen has a wide genetic variability and, therefore, poses a challenge to integrated disease management. The use of resistant cultivars is difficult; hence, the application of fungicides has been a common practice in common bean cultivation. P. griseola strains were morphophysiologically characterized and their sensitivity to common fungicides used to control ALS was studied. The strains were evaluated for sporulation capacity and a representative sample of 34 strains was bioassayed to determine their sensitivity to commercial concentrations of five fungicides, namely pyraclostrobin, mancozeb, pyraclostrobin + metconazole, chlorothalonil and tebuconazole. Another sample of 29 strains was studied for conidial germination and dimensions. Sporulation capacity ranged from 0.88 to 27.67 × 10⁴ conidia/ml and germination percentage ranged from 39% to 72%. The large differences among strains suggest a wide genetic variability among the strains. A wide variability in aggressiveness of P. griseola was observed, which has consequences for breeding programmes aimed at resistance. The behaviour of pathogen strains differed in every fungicide evaluated, even in a population that has not been under selection pressure in the field. These results confirm the need for further studies and may guide future research with this pathogen.  相似文献   

Activin A as a novel biomarker of equine inflammatory abdominal disease: preliminary findings     

Forbes G  Sorich E  Nath LC  Church S  Savage CJ  Bailey SR 《Veterinary journal (London, England : 1997)》2011,190(2):e154-e156

This study evaluated the inflammatory mediator activin A in horses with acute abdominal disease and compared this putative novel biomarker with serum amyloid A (SAA). Thirty-three adult horses referred for evaluation of acute abdominal disease were grouped into three lesion categories, non-strangulating, strangulating or inflammatory. Eleven healthy adult horses served as controls. Serum activin-A was significantly increased in animals with inflammatory or strangulating lesions compared with controls. Horses with non-strangulating, strangulating or inflammatory lesions had significantly elevated SAA concentrations. Activin A, along with other biomarkers, may be useful in monitoring inflammation in cases of acute abdominal disease in horses. Further validation is warranted to determine the utility of this biomarker in evaluating the effectiveness of novel anti-inflammatory treatments for equine colic and endotoxaemia.  相似文献   

Genetic control of surface curvature     

Nath U  Crawford BC  Carpenter R  Coen E 《Science (New York, N.Y.)》2003,299(5611):1404-1407

Although curvature of biological surfaces has been considered from mathematical and biophysical perspectives, its molecular and developmental basis is unclear. We have studied the cin mutant of Antirrhinum, which has crinkly rather than flat leaves. Leaves of cin display excess growth in marginal regions, resulting in a gradual introduction of negative curvature during development. This reflects a change in the shape and the progression of a cell-cycle arrest front moving from the leaf tip toward the base. CIN encodes a TCP protein and is expressed downstream of the arrest front. We propose that CIN promotes zero curvature (flatness) by making cells more sensitive to an arrest signal, particularly in marginal regions.  相似文献   

Understanding Brown Planthopper Resistance in Rice: Genetics,Biochemical and Molecular Breeding Approaches     

Muduli Lakesh  Kumar Pradhan Sukanta  Mishra Abinash  Nath Bastia Debendra  Chandra Samal Kailash  Kumar Agrawal Pawan  Dash Manasi 《水稻科学》2021,28(6):532-546

Brown planthopper (BPH, Nilaparvata lugens Stål) is the most devastating pest of rice in Asia and causes significant yield loss annually. Around 37 BPH resistance genes have been identified so far in indica, African rice varieties along with wild germplasms such as Oryza officinalis, O. minuta, O. nivara, O. punctata, O. rufipogon and O. latifolia. Genes/QTLs involved in BPH resistance, including Bph1, bph2/BPH26, Bph3, Bph6, bph7, BPH9, Bph12, Bph14, Bph15, Bph17, BPH18, bph19, Bph20, Bph21(t), Bph27, Bph27(t), Bph28(t), BPH29, QBph3, QBph4, QBph4.2, Bph30, Bph32, Bph33, Bph35 and Bph36, have been fine-mapped by different researchers across the globe. The majority of genes/QTLs are located on rice chromosomes 1, 3, 4, 6, 11 and 12. Rice plants respond to BPH attack by releasing various endogenous metabolites like proteinase inhibitors, callose, secondary metabolites (terpenes, alkaloids, flavonoid, etc.) and volatile compounds. Besides that, hormonal signal pathways mediating (antagonistic/synergistic) resistance responses in rice have been well studied. Marker-assisted breeding and genome editing techniques can also be adopted for improving resistance to novel BPH biotypes.  相似文献   

Reduced cell wall degradation plays a role in cow dung-mediated management of wilt complex disease of chickpea     

Chandra Shekhar Nautiyal  Suchi Srivastava  Sandhya Mishra  Mehar Hasan Asif  Puneet Singh Chauhan  Poonam C. Singh  Pravendra Nath 《Biology and Fertility of Soils》2013,49(7):881-891

  相似文献