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11.
Eighteen genotypes of Brassica napus were crossed to a cytoplasmic male sterile (CMS) line of B. napus BO 15 carrying B. tournefortii cytoplasm (‘tour’ cytoplasm). Fourteen genotypes were found to be stable maintainers of the ‘tour’ CMS. Of the remaining four genotypes, GSL-1 and ‘Asahi-natane’ were found to be heterozygous and ‘Mangun’ and ‘Yudal’ were homozygous for the restorer gene. Analysis of the F1 and F2 progenies of (CMS) BO 15 בMangun’ and (CMS) BO 15 בYudal’ showed that fertility restoration is controlled by a single dominant gene. The availability of a number of stable maintainer lines and the simple inheritance pattern of fertility restorer gene makes ‘tour’ CMS a useful system for hybrid seed production in rapeseed.  相似文献   
12.
In vitro studies with organ (oviduct and trachea) and chicken embryo kidney cell cultures were attempted to assess the pathogenicity of locally isolated infectious bronchitis virus (IBV-P:120) initially isolated from the oviduct of young chicks. In oviduct cultures infected with IBV, ciliary movements decreased as early as 24 hours postinoculation (PI), and on the 6th day ciliary movements ceased completely. Cytopathic changes were also noticed. Immunofluorescent antigen was detected from 1 to 6 days PI, the maximum being on the 3rd day. The characteristic microscopic changes in the oviduct explants were reduced by 24 hours PI and had completely ceased on the 5th day. Cytopathic effect and immunofluorescent antigen were present from 1 to 8 days PI, being maximum on the 5th day. Histological changes marked by loss of cilia, rounding of the epithelial cells, degeneration, and sloughing were detected from 2 to 8 days PI. Low-embryo-passaged (EP-7) IBV did not produce cytopathic effect on the chicken embryo kidney cell cultures. On the contrary, high-embryo-passaged (EP-14) virus produced cytopathic effect at the third tissue-culture-passage level.  相似文献   
13.
Marek's disease-associated tumour surface antigen (MATSA) removed by enzymatic (papain) digestion of Marek's disease tumour cells was fractionated by gel filtration chromatography. The first peak (F1) was used to raise antibody in rabbits. Monoclonal antibody (RPH-6) directed against MATSA and the anti-F1 IgG were used as idiotypic antibodies to raise polyclonal anti-idiotype serum in heterologous hosts; rabbit and goat, respectively. The anti-idiotypes (anti-Id) were purified by affinity chromatography and characterized by competitive binding assay using immunofluorescent (IF) tests.

Day-old white Leghorn chicks were immunized with anti-Id to MATSA (Group 1) or anti-Id to F1 (Group 3) and challenged with virulent Marek's disease virus (MDV) on the tenth day post immunization. In positive control groups, the day-old chicks were inoculated with anti-BALB/c mouse globulin (Group 2) and anti-rabbit globulin (Group 4) and challenged with virulent MDV on the tenth day post inoculation. As compared with positive control groups, the vaccinated groups (1 and 3) had considerably lower level of MATSA positive cells during the post challenge observation period. The protection level against MD in the immunized groups was 66.6% (Group 1) and 86.6% (Group 3).  相似文献   

14.
We investigated the effects of Arbuscular Mycorrhiza (AM) fungi and various phosphorus (P) levels on the distribution and availability of P in dominant soils of Bihar, India. Potassium chloride (KCl)-P (labile P), sodium hydroxide (NaOH)-P (Fe-Al-bound P), hydrochloric acid (HCl)-P (Ca-bound P), and residual P (Res-P) fractions were analyzed in the soils under maize plant. Ca-bound P was the most abundant P fraction in the alkaline soils (65% of the total P) followed by neutral soil (35% of the total P), whereas it was less abundant (<4%) in the acidic soil type. Fe-Al-bound P was found to be highest for acidic soil (65% of the total P). Soils under the inoculation with Glomus mossae and control gave the highest and lowest values (15.63 mg kg?1 and 10.74 mg kg?1 respectively) for the labile fraction which was similar to the organically bound residual fractions of P (200.17 mg kg?1 and 193.66 mg kg?1 respectively. Inoculation of the soils with AM fungi leads to the redistribution of P fractions in different soils which consequently helps in improvement of available P in soil conducive for plant uptake.  相似文献   
15.
Since cattle are widely infected by bovine viral diarrhea virus (BVDV) in India, we searched for pestivirus infection in yaks. Of 71 pure and crossbred yaks from Himalayan region, pestivirus antigen was detected by Ag-ELISA in three animals. Pestivirus in leukocyte and cell culture isolated virus samples originating from positive yaks was also confirmed by RT-PCR using panpestivirus specific primers selected from 5'-untranslated region (5' UTR). The 5' UTR, N(pro) and E2 regions were sequenced and used for genetic typing. Phylogenetic analysis revealed that pestiviruses detected in three Himalayan yaks were similar genetically, belonging to BVDV-1. Antigenic characterisation of yak pestivirus also confirmed the typing as BVDV-1. This is the first report on the identification of BVDV type 1 in yaks.  相似文献   
16.
A triploid hybrid with an ABC genome constitution, produced from an interspecific cross between Brassica napus (AACC genome) and B. nigra (BB genome), was used as source material for chromosome doubling. Two approaches were undertaken for the production of hexaploids: firstly, by self-pollination and open-pollination of the triploid hybrid; and secondly, by application of colchicine to axillary meristems of triploid plants. Sixteen seeds were harvested from triploid plants and two seedlings were confirmed to be hexaploids with 54 chromosomes. Pollen viability increased from 13% in triploids to a maximum of 49% in hexaploids. Petal length increased from 1.3 cm (triploid) to 1.9 cm and 1.8 cm in the two hexaploids and longest stamen length increased from 0.9 cm (triploid) to 1.1 cm in the hexaploids. Pollen grains were longer in hexaploids (43.7 and 46.3 μm) compared to the triploid (25.4 μm). A few aneuploid offsprings were also observed, with chromosome number ranging from 34 to 48. This study shows that trigenomic hexaploids can be produced in Brassica through interspecific hybridisation of B. napus and B. nigra followed by colchicine treatment.  相似文献   
17.
Deeper rooting 1(Dro1) and Deeper rooting 2(Dro2) are the QTLs that contribute considerably to root growth angle assisting in deeper rooting of rice plant. In the present study, a set of 348 genotypes were shortlisted from rice germplasm based on root angle study. Screening results of the germplasm lines under drought stress identified 25 drought tolerant donor lines based on leaf rolling, leaf drying, spikelet fertility and single plant yield. A panel containing 101 genotypes was constituted based on screening results and genotyped using Dro1 and Dro2 markers. Structure software categorized the genotypes into four sub-populations with different fixation index values for root growth angle. The clustering analysis and principal coordinate analysis could differentiate the genotypes with or without deeper rooting trait. The dendrogram constructed based on the molecular screening for deep rooting QTLs showed clear distinction between the rainfed upland cultivars and irrigated genotypes. Eleven genotypes, namely Dular, Tepiboro, Surjamukhi, Bamawpyan, N22, Dinorado, Karni, Kusuma, Bowdel, Lalsankari and Laxmikajal, possessed both the QTLs, whereas 67 genotypes possessed only Dro1. The average angle of Dro positive genotypes ranged from 82.7° to 89.7°. These genotypes possessing the deeper rooting QTLs can be taken as donor lines to be used in marker-assisted breeding programs.  相似文献   
18.
19.
Two shallow lowland male sterile lines, MotiA and PadminiAwith Miz.4 cytoplasmic source were developed throughintervarietal hybridization and recurrent backcrossing withtheir respective parents. In all probability, MotiA and PadminiA of Miz.4 source may be genetically different from the Wild abortive CMS source (V.20A). These two CMS lines are semitall in stature, photosensitive, of late duration in flowering with easy fertility restoration ability, and thus could be useful for developing hybrid rice suitable for shallow lowland areas.  相似文献   
20.
The increasing drug resistance of infectious microorganisms is considered a primary concern of global health care. The screening and identification of natural compounds with antibacterial properties have gained immense popularity in recent times. It has previously been shown that several bioactive compounds derived from marine algae exhibit antibacterial activity. Similarly, polyphenolic compounds are generally known to possess promising antibacterial capacity, among other capacities. Phlorotannins (PTs), an important group of algae-derived polyphenolic compounds, have been considered potent antibacterial agents both as single drug entities and in combination with commercially available antibacterial drugs. In this context, this article reviews the antibacterial properties of polyphenols in brown algae, with particular reference to PTs. Cell death through various molecular modes of action and the specific inhibition of biofilm formation by PTs were the key discussion of this review. The synergy between drugs was also discussed in light of the potential use of PTs as adjuvants in the pharmacological antibacterial treatment.  相似文献   
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