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71.
During last decades, stripe rust has emerged as a major disease of wheat causing considerable yield loss in northern western plain and northern hill zones of India. Considering significant impact of the disease on wheat crop, field experiments were conducted during rabi seasons of 2013 and 2015 to evaluate the effect of different abiotic factors in different varieties (HD 2967, RSP 561, Agra Local and PBW 343) on the progress and spread of the disease as well as development of a predictive model to predict the disease initiation and spread in the field. Statistical analysis of data revealed that existing of low temperature (10–12 °C), high relative humidity (90%) along with intermittent rainfall was found conducive for disease onset. Thermic variables (atmospheric, canopy and soil temperature) along with age of crop in the selected varieties showed significant positive correlation with disease severity. Step-wise regression showed high R2 of 0.919, 0.885, 0.967 and 0.956 for the predicative model of stripe rust in RSP 561, HD 2967, Agra Local and PBW 343, respectively.  相似文献   
72.
Click reaction approach toward the synthesis of two sets of novel 1,2,3-triazolyl linked uridine derivatives 19a19g and 21a21g was achieved by Cu(I)-catalyzed 1,3-dipolar cycloaddition of 5′-azido-5′-deoxy-2′,3′-O-(1-methylethylidene)uridine (17) with propargylated ether of phenols 18a18g and propargylated esters 20a20g. Structure of one of the representative compound 19d was unambiguously confirmed by X-ray crystallography. Chitin synthase inhibition study of all these compounds 19a19g and 21a21g was carried out to develop antifungal strategy. Compounds 19d, 19e, 19f, and 21f were identified as potent chitin synthase inhibitors by comparing with nikkomycin. Compounds 19a, 19b, 19c, 19d, 21a, and 21b showed good antifungal activity against human and plant pathogens. Compounds 19a, 19b, 19f, 21c, 21f, and 21g were identified as lead chitin synthase inhibitors for further modifications by comparing results of inhibition of growth, % germ tube formation and chitin synthase activity.  相似文献   
73.

Background  

Previously it has been shown that insulin-mediated tyrosine phosphorylation of myosin heavy chain is concomitant with enhanced association of C-terminal SRC kinase during skeletal muscle differentiation. We sought to identify putative site(s) for this phosphorylation event.  相似文献   
74.
The essential oil (EO) obtained from the fresh and dried leaves of Cinnamomum tamala was analysed by gas chromatography/mass spectrometry. EO from fresh leaves showed the presence of 21 compounds, whereas, EO from the dried leaves of C. tamala showed the presence of 20 compounds. In vitro assays namely scavenging ability against 1,1-diphenyl-2-picrylhydrazyl, reducing power and chelating ability on Fe2+ ions were used to determine the antioxidant potential of EO of C. tamala. With regard to antifungal activity, EO from dried leaves was more effective against Alternaria alternata and Curvularia lunata than the EO from fresh leaves. Similarly, EO from C. tamala leaves also showed potent antibacterial activity against two Gram negative and two Gram positive bacteria namely, Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus and Pseudomonas aeruginosa. Furthermore, bioactive molecule from C. tamala EO having antifungal and antioxidant activity was isolated and characterized using bioautography, preparative thin layer chromatography and GC/MS analysis and was determined as eugenol. Its minimum inhibitory amount against A. alternata and C. lunata was determined using bioautography assay and was found to be 9.5 and 8.2 µg respectively.  相似文献   
75.
Production of haploid plants has been restricted to only a few ornamental species. In this paper an efficient anther culture protocol has been devised for production of haploid plants of Phlox drummondii, a garden ornamental. Anthers with microspores at early- to late-uninucleate stages were inoculated on MS (Murashige and Skoog, Physiol Plant 15:473–479, 1962) basal medium containing 9% sucrose, 10 μM 2,4-D + 5 μM BA in the dark for callus induction. The callus (~2 mm) was transferred to MS medium containing 3% sucrose + 10 μM BA + 5 μM NAA under a 16 h photoperiod for multiplication. Anther-derived callus showed the greatest shoot differentiation (60% with greater than 3 shoots per culture) at 13 weeks after culture initiation when maintained on MS medium supplemented with 3% sucrose and cytokinin (7.5 μM BA). At 68 weeks, only 4.6% of cultures differentiated with less than one shoot per callus. Anther-derived shoots rooted readily on MS medium containing 7.5 μM IAA. Of 60 plants that regenerated from anther callus, 50% were haploid, 30% diploid, and 20% aneuploid. Developed protocol could be useful for the haploid induction of outcrossing ornamental plants for production of their homozygous double haploids.  相似文献   
76.
Triploid plants of neem were obtained by immature endosperm culture. Immature seeds, at the early dicotyledonous stage of embryo development, is the best explant to raise endosperm callus on MS + NAA (5 mumol/L) + BAP (2 mumol/L) + CH (500 mg L-1). Maximum shoot bud differentiation from the endosperm callus occurred on MS + 5 mumol/L BAP. Shoots were multiplied by forced axillary branching and rooted in vitro. The plants were established in soil. Over 66% of the plants were triploid with chromosome number 2n = 3x = 36. A characteristic feature of the shoots of endosperm origin is the presence of a large number of multi-cellular glands.  相似文献   
77.
Three new triterpenoids, designated as koelpinin-A, B and C and characterised as 28-nor-lup-12,17-dien-3 beta,16 alpha-diol,3 beta-acetoxy-28-nor-lup-12,17-dien-16 alpha-ol and 28-nor-lup-12,17-dien-3 beta-ol-16-one, respectively, together with 30-nor-lup-3 beta-ol-20-one, taraxeryl acetate and germanicol, were isolated, from the aerial parts of Koelpinia linearis. 13C-NMR shifts were assigned after performing APT and DEPT experiments.  相似文献   
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