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61.
Transgenic of Indian potato cultivar Kufri Badshah expressing synthetic, modified cry1Ab gene were developed against potato tuber moth (Phthorimaea opercullela Z.) a destructive pest. The cry1Ab gene was in spatial and temporal expression under the control of tuber-specific GBSSi promoter. The transformation vector pBinCG1 was developed harbouring transgene expression cassette comprising cry1Ab gene under the control of potato GBSSi promoter, castor bean catalase intron (5′UTR) and OCS termination signals. Selected kanamycin-resistant putative transformed potato lines were evaluated by positive PCR amplification of 713 bp, 1206 bp and 700 bp with npt II, GBSSi promoter and cry1Ab gene specific primers, respectively. Gene integration in transformed potato plants was elucidated through Southern hybridization and in planta transgene expression analysis. Transgene expression was highest in stolons, followed by tubers matured leaves and young leaves. Insect bioassay of stored transgenic tubers resulted in significant retardation and mortality in neonate tuber moth larvae. RT-PCR and northern hybridization confirmed stable expression in stored tubers. These transgenic lines; thus can represent an effective resistance management strategy which can significantly reduce the selection pressure on target and non-target insect pests to a threshold level.  相似文献   
62.
Thirty-eight Indian potato varieties and fifty-two advanced hybrid lines were analyzed for cytoplasm types using both plastid and mitochondrial genome specific markers. Indian genotypes thus analysed could be broadly grouped into 4 cytoplasm types i.e. T/β (69), W/α (18), W/γ (1) and A/ɛ (2). The T/β type cytoplasm, typical of common cultivated potato (ssp. tuberosum) was absent in six released varieties (Kufri Chipsona-1/-2/-3 series, Kufri Jawahar, Kufri Megha and Kufri Himalini) and fifteen out of fifty two hybrids analyzed. This information was further used to predict cytoplasm type on the basis of common shared maternal pedigree in thirty-eight other advanced hybrids, which revealed majority (25) had T/β type cytoplasm with W/α and A/ɛ cytoplasm observed in 12 and 1 genotype, respectively. T/β type cytoplasm was observed in all 28 early bulking hybrids studied along with all old genotypes. It was revealed that considerable broadening of maternal base was observed in recently developed genotypes. W/α type cytoplasm was present in most of processing (all 3 chipping varieties and 9 of 12 MP hybrids) and late blight resistant (11of 23 hybrids) genotypes.  相似文献   
63.
Paddy and Water Environment - Traditional rice–wheat cropping system, which follows wet puddling in rice and conventional tillage in wheat, is deteriorating soil health resulting yield...  相似文献   
64.
Cytoplasmic-nuclear male-sterility is an important biological tool, which has been used by plant breeders to increase yields in cross-pollinated cereals and vegetables by commercial exploitation of the phenomenon of hybrid vigor. In legumes, no such example exists due to the absence of an economic way of mass pollen transfer from male to female parent. Pigeonpea [Cajanus cajan (L.) Millsp.], however, is a different legume where a moderate level of insect-aided natural out-crossing (25–70%) exists and it can be used to produce commercial hybrid cultivars, if an efficient and stable cytoplasmic-nuclear male-sterility (CMS) system is available. This paper reports the development of a stable CMS system (ICP 2039A), derived from an inter-specific hybrid of Cajanus cajanifolius, a wild relative of pigeonpea, with a cultivar ICP 11501. Using this genetic material, designated as the A4 cytoplasm, a number of fertility restorers and maintainers have been developed. The best short-duration experimental pigeonpea hybrid ICPH 2470 produced 3205 kg ha−1 grain yield in 125 days, exhibiting 77.5% advantage over the control cultivar UPAS 120. At present, all the important biological systems necessary for a successful commercial hybrid breeding program are available in pigeonpea and the package of this technology has been adopted by private seed sector in India for the production and marketing of hybrid varieties.  相似文献   
65.
Ancymidol was investigated as an alternative mediumsupplement to mannitol for slow-growth conservation ofpotato microplants in vitro. Differentconcentrations of ancymidol (0, 5, 10, 15, 20, 25, 30,35 and 40 M) were tested in slow-growthmedia based on MS medium supplemented with either 30or 60 gl-1 sucrose. The cultures were conservedunder a 16-h photoperiod at two temperature regimesi.e. 24 ± 1 °C and 6 ± 1 °C. Therewere significant interactions between ancymidol andother factors such as sucrose, temperature andgenotype for microplant survival, microshoot heightand overall microplant growth. Ancymidol did have abeneficial effect on culture viability after prolongedmaintenance in vitro. The growth-inhibitingeffect of ancymidol persisted through a 16-monthculture period. Combined effect of ancymidol, sucroseand temperature showed that optimum culture viabilityand desirable microplant growth were obtained when thecultures were grown in MS medium supplemented with 10M ancymidol plus 60 gl-1 sucrose at6 ± 1 °C. Vitrification and flaccidity, whichare very frequently observed in potato microplantcultures during prolonged maintenance in vitrounder osmotic stress (mannitol), were not observedwhen the microplants were conserved in ancymidolmedia. Genetic stability of potato microplantsconserved in ancymidol media was evaluated usingrandomly amplified polymorphic DNA (RAPD)fingerprints. Ancymidol did not induce any detectablegenetic variation in genomic DNA as visualized by theabsence of either any additional RAPD fragment oralterations in RAPD fragment patterns.  相似文献   
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68.
Hamycin activity (in vitro) against Malassezia ovale was studied and compared with old and newly discovered polyene antifungal antibiotics. Hamycin showed a marked anti-M. ovale activity which was enhanced in the presence of divalent cations like Cu++ and Zn++. Furthermore, the absorption of hamycin onto the cell membrane or cell surface of M. ovale was also increased in the presence of divalent cations. It is suggested that hamycin alone or along with metal ions, specifically Cu++ may be useful clinically in the treatment of dandruff or seborrheic dermatitis.  相似文献   
69.
The hydraulics of pitcher irrigation in saline water condition was studied in laboratory conditions in terms of flow behaviour of pitcher, soil moisture distribution, wetting front advance and distribution of salt concentration in the soil using different pitcher making materials. The Pitcher Type 1 (PT1) made up of local soil and sand yielded the lowest mean hourly depletion ranging from 0.42 to 0.62% depending on salinity of the water used. It was followed by PT2 made up of local soil, sand and resinous material with a mean hourly depletion of 0.51-0.69% and PT3 with local soil, saw dust and sand with a mean hourly depletion of 0.91-1.02%. In all cases, with the increase in salinity level of the water used (ranging from 5 to 20 dS/m), the depletion rate and moisture content in the soil profile were found to decrease.Similarly, it was found that PT1 yielded the lowest wetting front advance and salt movement followed by PT2 and PT3. It was observed that the wetting front advance in the soil decreased with increasing salinity level of the water. The salt concentration in the soil was minimum near the pitcher and maximum at the soil surface and periphery of the wetted zone. In case of PT1, the maximum salt concentration in the soil profile ranged between 1.09 and 3.88 dS/m using water with a salinity ranging from 5 to 20 dS/m, respectively. Similarly, for PT2 the maximum salt concentration in the soil profile also ranged from 1.09 to 3.88 dS/m and for PT3 from 2.30 to 6.07 dS/m. A paired t-test revealed that the moisture as well as the salt distribution of PT3 differed significantly from PT1 and PT2 at α = 0.05. Even, if the salt concentration remained the same and the moisture content remained within field capacity for PT1 and PT2, PT1 is preferred in comparison to PT2 and PT3 as the pitcher material of PT1 is locally economically available.  相似文献   
70.
Naik SR  Panda VS 《Fitoterapia》2008,79(6):439-445
The protective effects of Ginkgoselect Phytosome((R)) (GBP) on Rifampicin (RMP) induced hepatotoxicity and the probable mechanism(s) involved in this protection were investigated in rats. Liver damage was induced in Wistar rats by administering rifampicin (500 mg/kg, p.o.) daily for 30 days. Simultaneously, GBP at 25 mg/kg and 50 mg/kg, and the reference drug silymarin (100 mg/kg) were administered orally for 30 days/daily to RMP treated rats. Levels of marker enzymes (SGOT, SGPT and SALP), albaumin (Alb) and total proteins (TP) were assessed in serum. The effects of GBP on lipid peroxidation (LPO), reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione reductase (GR) were assayed in liver homogenates to evaluate antioxidant activity. GBP (25 and 50 mg/kg) and silymarin elicited a significant hepatoprotective activity by lowering the levels of serum marker enzymes and lipid peroxidation and elevated the levels of GSH, SOD, CAT, GPX, GR, Alb and TP in a dose dependant manner. The present findings suggest that the hepatoprotective effect of GBP in RMP induced oxidative damage may be related to its antioxidant and free radical scavenging activity.  相似文献   
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