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1.
Sujata Mohapatra Rajesh Kumar Srianga Tilak Patnaik Choudhury Suryakant Mishra Lakshman Sahoo Jitendra Kumar Sundaray 《Aquaculture Research》2020,51(8):3230-3236
Monocrotophos (MCP) is one of the organophosphate pesticides extensively used in agriculture and animal husbandry. The present study reports the effects of sub‐lethal concentrations of MCP on gonadosomatic index (GSI), gonadal histology and breeding fitness of the fish Anabas testudineus. The fish were exposed to three sub‐lethal concentrations of monocrotophos (T1: 3.5 mg/L, T2: 5.3 mg/L and T3: 10.6 mg/L) for 45 days with 12 fish (males and females in equal numbers) in each tank, and one group was kept as control (C) without any treatment. GSI decreased in all treatment groups in comparison with control. Significant decrease in fertilization and hatching rate was observed at all concentrations in comparison with control on 15, 30 and 45 days of monocrotophos exposure. The decreased vitellogenesis, disruption of follicular wall and oocyte atresia were observed in all the treated females at 30 and 45 days of exposure. Rupture of seminiferous tubules was noticed in all the treated males irrespective of exposure periods. The results thus indicated that monocrotophos could deleteriously impact the gonadal structure and function in A. testudineus, which could seriously impact the reproductive success of the animal. 相似文献
2.
Umesh PANKAJ Durgesh Narain SINGH Pooja MISHRA Pooja GAUR C. S. Vivek BABU Karuna SHANKER Rajesh Kumar VERMA 《土壤圈》2020,30(5):671-683
Phytoremediation is a promising approach for reclamation of salt-affected soil. Phytoextraction is the most commonly used process, which exploits plants to absorb, immobilize, and accumulate salt in their shoots. In this study, halotolerant plant growth-promoting rhizobacteria (PGPR) were isolated from the rhizosphere of wild grasses growing naturally in salt-affected areas of Lucknow, Uttar Pradesh (India) and were tested for their efficacies of salt-tolerance and plant growth-promoting (PGP) abilities. Based on 16S rRNA sequences, the most efficient halotolerant isolates possessing PGP traits were identified as Pseudomonas plecoglossicida (KM233646), Acinetobacter calcoaceticus (KM233647), Bacillus flexus (KM233648), and Bacillus safensis (KM233652). Application of these isolates as bio-inoculants significantly (P < 0.05) increased the growth and bacoside A yield of a medicinal plant, Bacopa monnieri (L.) Nash, grown on natural salt-affected soil. The phytoremediation of salt-affected soil was evident by the substantial increase in shoot Na+:K+ ratio of bio-inoculant-treated plants. When compared to un-inoculated control plants, the soil physico-chemical properties of bio-inoculant-treated plants were improved. The shoot and root biomass (fresh and dry weights), soil enzymes, and soil nutrient parameters showed significant positive correlations with the shoot Na+:K+ ratio. Consequently, the halotolerant PGPR screened in this study could be useful for the reclamation of saline soils concomitant with improved plant growth and bacoside A yield. 相似文献
3.
4.
The growth hormone (GH) gene isolated and cloned from various Labeo species (L. rohita, L. calbasu, L. fimbriatus, L. gonius, L. bata, and L. kontius) is shown to contain a single copy in the haploid genome, with an overall size of ∼2.5 kb. The GH gene in all the Labeo species studied has five exons and four introns of various sizes with the exon/intron boundary sequence of GT/AG. The length
variation of the GH gene between the species is found to be due to length variation in the form of several deletions in the
third intron. The length of individual exons is the same in all the species with an open reading frame (ORF) of 630 bp (210
amino acids) except in L. rohita, which has a 9 bp deletion in the fourth exon, resulting in a shorter GH of 621 bp (207 amino acids). The similarity in the
nucleotide and amino acid sequences between the different Labeo species is greater than 97%, in spite of eight amino acids being altered in the GH protein of Labeo that reside outside the conserved domain sequence required for its function. Nucleotide substitutions are seen in the form
of 20 transitions and three transversions in the ORF of the GH gene. Both types of transitions (A–G; T–C) and only one type
of transversion (A–C) are detected in the GH gene. Codon preference in GH gene shows a strong preference for G and C in the
wobble position of the codons. Genetic interrelationships determined between Labeo and other species of fishes using nucleotide sequence of GH cDNA supports the overall teleost classification of Nelson (Fishes
of the World. Wiley, New York, 1984) with separate clades for Ostariophysi, Protacanthopterygii, and Acanthopterygii. Besides, the unweighted pair group method
with arithmetic means (UPGMA) analysis clearly distinguishes between the species having five exons and four introns in the
GH gene from the species having six exons and five introns in the same gene. The Labeo species analyzed in the present study could be clustered into two groups using the maximum-parsimony method on the intron
sequences data of the GH gene. 相似文献
5.
In the present study, nanofibrils of cellulose are extracted from waste jute fibers using high energy planetary ball milling process in wet condition. The rate of refinement of untreated fibers having non-cellulosic contents was found slower than treated fibers due to strong holding of fiber bundles by non-cellulosic contents. At the end of three hours of wet milling, untreated fibers were refined to the size of 850 nm and treated fibers were refined to the size of 443 nm. In the subsequent stage, composite films of poly lactic acid (PLA) were prepared by solvent casting with 3 wt% loading of untreated jute nanofibrils, treated jute nanofibrils and microcrystalline cellulose. The influence of non-cellulosic contents on mechanical properties of PLA films are investigated based on results of tensile test, dynamic mechanical analysis and differential scanning calorimetry. The maximum improvement was observed in case of treated jute nanofibril/PLA composite film where initial modulus and tensile strength increased by 207.69 % and 168.67 %, respectively as compared to neat PLA film. These improvements are attributed to the increased interaction of treated jute nanofibrils with PLA matrix due to their higher precentage of cellulosic contents and mechanically activated surface. 相似文献
6.
Frederick J. Muehlbauer Seungho Cho Ashutosh Sarker Kevin E. McPhee Clarice J. Coyne P. N. Rajesh Rebecca Ford 《Euphytica》2006,147(1-2):149-165
Summary Lentil is a self-pollinating diploid (2n = 14 chromosomes) annual cool season legume crop that is produced throughout the world and is highly valued as a high protein
food. Several abiotic stresses are important to lentil yields world wide and include drought, heat, salt susceptibility and
iron deficiency. The biotic stresses are numerous and include: susceptibility to Ascochyta blight, caused by Ascochyta lentis; Anthracnose, caused by
Colletotrichum truncatum; Fusarium wilt, caused by
Fusarium oxysporum; Sclerotinia white mold, caused by
Sclerotinia sclerotiorum; rust, caused by
Uromyces fabae; and numerous aphid transmitted viruses. Lentil is also highly susceptible to several species of
Orabanche prevalent in the Mediterranean region, for which there does not appear to be much resistance in the germplasm. Plant breeders
and geneticists have addressed these stresses by identifying resistant/tolerant germplasm, determining the genetics involved
and the genetic map positions of the resistant genes. To this end progress has been made in mapping the lentil genome and
several genetic maps are available that eventually will lead to the development of a consensus map for lentil. Marker density
has been limited in the published genetic maps and there is a distinct lack of co-dominant markers that would facilitate comparisons
of the available genetic maps and efficient identification of markers closely linked to genes of interest. Molecular breeding
of lentil for disease resistance genes using marker assisted selection, particularly for resistance to Ascochyta blight and
Anthracnose, is underway in Australia and Canada and promising results have been obtained. Comparative genomics and synteny
analyses with closely related legumes promises to further advance the knowledge of the lentil genome and provide lentil breeders
with additional genes and selectable markers for use in marker assisted selection. Genomic tools such as macro and micro arrays,
reverse genetics and genetic transformation are emerging technologies that may eventually be available for use in lentil crop
improvement. 相似文献
7.
8.
Manoj Kumar Solanki Nidhi Singh Rajesh Kumar Singh Pratiksha Singh Alok K. Srivastava Sudheer Kumar Prem L. Kashyap Dilip K. Arora 《Phytoparasitica》2011,39(5):471-481
Tomato root rot caused by Rhizoctonia solani is a major soilborne disease resulting in significant yield loss. The culture filtrates of six isolates of Trichoderma/Hypocrea species were evaluated for in vitro production of hydrolytic enzymes. Results demonstrated that all the six isolates were able to produce chitinase, β-1, 3 glucanase
and protease in the range of 76–235 μmol GlcNAc min-1 mg-1 protein, 31.90–37.72 nmol glucose min-1 mg-1 proteins and 63.05–86.22 μmol min-1 mg-1 proteins, respectively. Trichoderma/Hypocrea-based formulation(s) were prepared with chitin (1% v:v) and CMC (0.5% w:v) for root rot management in a greenhouse. Root dip
application with bioformulation(s) resulted in a significant reduction of the root rot index. In addition, bioformulations
increased plant growth attributing traits significantly relative to untreated control. Accumulation of total phenols, peroxidase,
polyphenoloxidase and phenylalanine ammonia lyase increased in chitin-supplemented Trichoderma/Hypocrea formulation-treated plants challenged with R. solani. The results suggest that chitin-fortified bioformulation(s) could be an effective system to control root rot of tomato in
an eco-compatible manner. 相似文献
9.
Young rabbit appendix is a homologue of chicken bursa of Fabricius; both are crucial sites for preimmune B-cell repertoire diversification. Here, we report that appendix regulates precursor lymphocyte recruitment for further development by modulating the sites of extravasation. The total area of peripheral node addressin-positive (PNAd(+)) high endothelial venules (HEVs) increased from 1 day to 1 week after birth, remained constant up to 2 weeks and declined to a low and persistent amount by 3 weeks. In normal 1-week and manipulated 5-week appendix where growth of follicles was retarded, PNAd(+) HEVs were present in the basolateral sides of B-cell follicles whereas, in normal 5-wk-appendix these were restricted to T-cell areas. The PNAd was expressed on the lumenal surface of HEVs. The proportions of CD62L(+) B cells in appendix declined from approximately 40% at 3 days to 2-3% at 4 weeks. In lymphocyte transfer experiments, CD62L(+) B cells were preferentially recruited compared with CD62L(-) B cells, anti-PNAd antibody blocked migration of B cells by approximately 50%, and 100 times more B cells were recruited in 1-week compared to 6-week appendix. Thus, a unique spatiotemporal expression pattern of PNAd(+) HEVs is associated with development of B-cell follicles. This regulates migration of blood-borne B-lymphocytes into developing appendix by interacting with CD62L. 相似文献
10.
Ogawa H Chahota R Hagino T Ohya K Yamaguchi T Fukushi H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(7):743-745
Although birds infected with avian polyomavirus (APV) subclinically could be a source of infection, no epidemiological studies of APV in psittacine birds have been reported in Japan. In the present study, we investigated subclinical morbidity rate of APV in imported and domestically bred psittacine birds by polymerase chain reaction (PCR). Of 402 live birds from which blood or feather samples were taken between April, 2003 and March, 2004, 11 (2.7%) were found to be APV positive. The DNA sequences of the APV t/T antigen region were determined for five APV-positive randomly selected samples and were found to be conserved. 相似文献