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141.
Screening of pea germplasm for resistance to powdery mildew 总被引:1,自引:0,他引:1
J. C. Rana D. K. Banyal K. D. Sharma Manish K. Sharma S. K. Gupta Satish K. Yadav 《Euphytica》2013,189(2):271-282
Powdery mildew caused by Erysiphe pisi DC results heavy losses in the yield and quality of pods and seeds of pea crop. Germplasm comprising 701 accessions of garden and field pea originating from 60 countries were screened for powdery mildew resistance under natural epiphytotic conditions and 64 accessions found resistant in field screening for 2?years at one location were further screened both in field at two locations and artificially in laboratory to four isolates. The information was also obtained on the amount of genetic diversity and agronomic superiority in resistant accessions. Fifty-seven accessions showed resistant reaction for 3 consecutive years in field screening but only 14 accessions originating from 10 countries showed resistant reaction in laboratory screening against the four most prevalent isolates of E. pisi collected from different places in the area of experiment. Germplasm lines showed both complete and incomplete levels of resistance and variable reactions to different isolates. There was sufficient genetic diversity and agronomic superiority in the resistant accessions e.g. EC598655, EC598878, EC598704, IC278261, and IC218988, which may serve as useful genetic material to plant breeders for breeding pea varieties for powdery mildew resistance and high yield. 相似文献
142.
Gopal Panthi Nasser A. M. Barakat Prabodh Risal Ayman Yousef Bishweshwar Pant Afeesh R. Unnithan Hak Yong Kim 《Fibers and Polymers》2013,14(5):718-723
Easy fabrication, porosity, good mechanical properties, and composition controllable of the electrospun nanofiber mat make this material a promising candidate for wound dressing applications. In the present study, nylon6/gelatin electrospun nanofiber mats are introduced as novel wound dressing materials. The introduced mats were synthesized by electrospinning of nylon6 and gelatin mixtures, three mats containing different gelatin content were prepared; 10, 20 and 30 wt%. Interestingly, addition of the gelatin did not affect the mechanical properties of the nylon 6, moreover the mat containing 10 wt% gelatin revealed higher mechanical properties due to formation of spider-net like structure from very thin nanofibers (~10 nm diameter) bonding the main nanofibers. Biologically study indicates that gelatin incorporation strongly enhances the bioactivity performance as increasing the gelatin content linearly increases the MC3T3-E1 cell attachment. Overall, the obtained results recommend exploiting the introduced mats as wound dressing material. 相似文献
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144.
Rice planthoppers' damage on Pusa Basmati 1 cultivar was simulated with InfoCrop, a generic crop growth simulation model. The model was calibrated and validated with two experimental data sets on planthopper population and rice yield that were generated through differential insecticide application during the rainy season 2006 and 2007. Simulated yield and total dry matter (TDM) in various treatments over the two experiments were found to be proximal to the observed yields (R2 = 0.972, RMSE = 4.61%) and TDM (R2 = 0.949, RMSE = 3.25%), respectively. Likewise, the simulated yield and TDM losses were also respectively close to observed yield losses (R2 = 0.938, RMSE = 13.53%) and TDM losses (R2 = 0.835, RMSE = 19.12%), suggesting appropriate validation of planthopper damage mechanism on Pusa Basmati 1 rice. Economic injury levels (EILs) of planthoppers were simulated with two control expenditures involving two applications with each of monocrotophos and imidacloprid, and three market prices of Pusa Basamti 1 rice. The EIL exhibited a negative relationship with market value of produce but a positive one with expenditure on control measures. Simulated EILs were comparable to earlier established empirical EILs, indicating utility of simulation models for developing location specific EILs that may help in doing away with the use of blanket EILs. Iso-loss curves, devised through validated model, depicted combinations of crop age and planthopper population that resulted in similar yield losses. Both the EILs and iso-loss curves can be useful in monitoring planthopper populations and promoting judicious pesticide applications that would avoid unwarranted control expenditure and environmental contamination. The simulation models being based on detailed crop ecological and physiological processes and pest damage mechanism can thus aid in development of location-specific decision support tools and ensure precision in pest management decisions. 相似文献
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146.
R. K. Naresh R. S. Rathore S. S. Dhaliwal R. B. Yadav Dipender Kumar S. P. Singh Adil Nawaz Narendra Kumar Raj K. Gupta 《Paddy and Water Environment》2016,14(3):373-386
A 3-year field experiment was carried out with tillage crop establishment (TCE) and rice nourishment in north-western India to evaluate the effect of five crop establishment methods and seven fertility treatments on crop production, water productivity, profitability, and soil physical quality. Maximum panicle length (30.9 cm) was noted with F3 treatment and minimum (22.7 cm) with F0 treatment. Zinc application methods and timing had significantly effect on paddy yield. Maximum yield (5.22 t ha?1) was achieved in treatment F3 and minimum yield (2.65 t ha?1) was noted in F0 treatment. Results also revealed that root dry weight, root volume, and root length were recorded with higher values in F3 treatment and minimum in F0 treatment. TCE methods were recorded with higher values in raised beds system than T5 at all growth stages. Treatments T1 and T2 reduced the mean maximum soil temperature at transplanting zone depth by 3.6 and 2.7 °C compared to the T3. Paddy yield in T3 was always significantly less than in T5. On average, treatment T4 recorded about 13 % lower water use and 3.7 % higher water productivity compared to T5. Treatment T5 had higher bulk density. The cumulative infiltration for 498 min was about 2 times in treatment T1, 5 times in T3 and more than 8 times in T4 of the values in T5. Mean weight diameter of aggregates was higher in T4 followed by the T1 and lowest in T5. The study reveals that TCE methods T1 and T4 with F3 nourishment could be more viable options for rice crop in order to save input costs and enhance profitability. 相似文献
147.
Poonam Yadav Arpana Verma Dheer Singh Sachinandan De Tirtha Kumar Datta 《Reproduction in domestic animals》2012,47(6):e88-e91
The present study was aimed to validate expression stability of 6 housekeeping genes (viz. YWHAZ, SDHA, GAPDH, RPS15, RPS18 and RN18S1) in the oocytes and embryos of different stages in buffalo. A modified Trizol protocol was optimized for RNA isolation from as few as five oocytes. The expression level of selected genes was studied by an optimized real time PCR using DCT method and their stability of expression was evaluated by Microsoft Excel based visual application, geNORM. The analysis revealed that the RPS15 and GAPDH were the most stable genes across different samples. Also, the geometric mean of three genes (i.e. RPS15, RPS18 and GAPDH) were found suitable for normalization of real time PCR data from buffalo oocytes/embryos. The information would help in more accurate interpretation of gene expression data from oocytes/embryos towards understanding the molecular events in these cells during development. 相似文献
148.
Soni VK Yadav DK Bano N Dixit P Pathak M Maurya R Sahai M Jain SK Misra-Bhattacharya S 《Fitoterapia》2012,83(1):110-116
Annona squamosa (AS) has traditionally been used as ethnomedicine. We have earlier extracted and fractionated the twigs of AS based upon its bioactivity and observed its immune potentiating activity that was localized in its three fractions. Present communication deals with the phytochemical analysis and pharmacological investigation of the most active chloroform fraction that led to isolation and identification of a number of compounds whose structures were elucidated using 1D and 2D NMR spectroscopic analysis. Amongst the twelve pure compounds isolated, five compounds Lanuginosine (1), (+) -O- methylarmepavine (2), (+)-anomuricine (3), Isocorydine (4), and N-methyl-6, 7-dimethoxyisoquinolone (5) were evaluated in vivo for their immune modifier activities in BALB/c mice after oral administration at three log doses of 0.3, 1.0 and 3.0 mg/kg for 14 consecutive days. Of these, three compounds (1, 2 and 5) showed dose dependent immune stimulating activity. However, the uppermost activity was noted in the compound N-methyl-6, 7-dimethoxyisoquinolone at the 3.0 mg/kg oral dose. The activity was assessed in the form of increased splenic T and B cellular proliferation, up-regulated CD4+, CD8+ and CD19+ cell population and accentuation in the peritoneal macrophage function. The compound possibly acted modifying the expression of Th1- and Th2- cytokines via stimulation of pro-inflammatory Th1 cytokines IL-2 and IFN-γ. These results warrant the use of the above compounds as an efficient immune-stimulant or immune-adjuvant against diseases with immune suppression. The analogs of the compound may further be chemically synthesized to achieve desired immune modifying activity. 相似文献
149.
Vinayagamurthy Balamurugan Arnab Sen Gnanavel Venkatesan Vandana Bhanot Vineeta Yadav Veerakyathappa Bhanuprakash Raj Kumar Singh 《Journal of veterinary science (Suw?n-si, Korea)》2012,13(2):203-206
In this study, peste des petits ruminants virus (PPRV) was detected in frozen pooled tissue samples from a dead Asiatic lion (Panthera leo persica). The samples were negative for canine distemper virus and positive for PPRV nucleic acids when tested with one-step RT-PCR using the appropriate virus-specific primers. Subsequent amplification, cloning, and sequencing of the partial nucleocapsid, matrix, and fusion genes confirmed the presence of PPRV nucleic acid. Comparative sequence and phylogenetic analyses of the structural genes of the isolated virus confirmed that the virus belonged to Asian lineage IV and was closely related to PPRV circulating in India. 相似文献
150.
Candidatus Actinochlamydia pangasiae sp. nov. (Chlamydiales,Actinochlamydiaceae), a bacterium associated with epitheliocystis in Pangasianodon hypophthalmus 下载免费PDF全文
N Sood D K Verma M K Yadav Ravindra A K Dev T R Swaminathan N K Sood 《Journal of fish diseases》2018,41(2):281-290
Chlamydial infections are recognised as causative agent of epitheliocystis, reported from over 90 fish species. In the present study, the farmed striped catfish Pangasianodon hypophthalmus (14–15 cm, 70–90 g) with a history of cumulative mortality of about 23% during June and July 2015, were brought to the laboratory. The histopathological examination of gills from the affected fish revealed presence of granular basophilic intracellular inclusions, mostly at the base of the interlamellar region and in gill filaments. A concurrent infection with Trichodina spp., Ichthyobodo spp. and Dactylogyrus spp. was observed in the gills. The presence of chlamydial DNA in the gills of affected fish was confirmed by amplification and sequencing of 16S rRNA gene. BLAST‐n analysis of these amplicons revealed maximum similarity (96%) with Candidatus Actinochlamydia clariae. On the basis of phylogenetic analysis, it was inferred that the epitheliocystis agents from striped catfish were novel and belonged to the taxon Ca. Actinochlamydia. It is proposed that epitheliocystis agents from striped catfish will be named as Ca. Actinochlamydia pangasiae. The 16S rRNA gene amplicons from novel chlamydiae were labelled and linked to inclusions by in situ hybridisation. This is the first report of epitheliocystis from India in a new fish host P. hypophthalmus. 相似文献