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71.
Severe mosaic accompanied by leaf and fruit deformation symptoms was observed on banana plants growing in three banana farms of Uttar Pradesh, India. The disease incidence was approximately 18–25% at these locations during the three successive years from 2005 to 2007. The occurrence of Cucumber mosaic virus (CMV) was initially detected by bioassay, electron microscopic observations, Western blot immunoassay and RT-PCR. For molecular identification of virus, the RNA 1a, RNA 2b and RNA 3 genomic fragments were amplified by RT-PCR and sequenced. The sequence analysis of these genomic fragments revealed its highest identities and close relationships with Indian strains of CMV of subgroup IB; therefore, virus associated with the mosaic disease of banana was identified as an isolate of CMV of subgroup IB. In the limited reports existing from India, which provided preliminary serological or only coat protein-based identification of CMV infecting banana but the comprehensive studies were lacking. In the present communication, we present a detailed biological, serological and molecular characterization of CMV-Banana for the first time from India.  相似文献   
72.
Two-year rice (Oryza sativa L.)-based crop rotation of “maize (Zea mays L.) relay cropped by horse gram (Dolichos biflorus L.) in the first year followed by upland rice in the second year”, was reported earlier to increase phosphorus (P) uptake by rice through enhancing native arbuscular mycorrhizal (AM) activities. This crop rotation was compared with three other rice-based crop rotations practiced by the upland rice farmers of eastern India for AM-mediated P acquisition of upland rice through on-farm experiment in farmers' participatory mode during wet seasons of 2004, 2005, 2006, and 2007 in fixed plots. The farmers' rotations included (1) green gram (Phaseolus aureus) in first year followed by upland rice in second year; (2) black gram (Phaseolus mungo) in first year followed by upland rice in second year; and (3) radish (Raphanus sativus) in first year followed by upland rice in second year. “Maize–horse gram/rice” rotation encouraged maximum native AM fungal colonization (10.4–38.8%) and P uptake (2.2–2.6 mg P/g plant) by rice over other three farmers' rotations tested. Rice grain yield was also highest (2.25–2.35 t/ha) in the maize–horse gram/rice rotation.  相似文献   
73.
竹房屋系统的建造与实用建筑的方法有很大的区别。(1)原竹的利用和构架橡子作为主要的承载元素。(2)劈蔑竹和竹片胶合作为剪切壁,它能起到透风的作用,并能为其结构提供整体的稳定性;(3)根据危害和公共条件的程度作适当的竹子防腐处理;(4)在屋顶结构上,用于承载的接合点与软钢螺丝相结用于竹子的三角架;(5)竹席皱纹片用于顶部的包层。根据房屋的设计、内部的修饰和当地的条件,建造房屋时可采用低成本,在印度,每张板的价格为300~500卢比/m^2。为了改进技术,印度胶合板工业研究与培训所近几年修建了几个样板建筑。活动房的具体建筑、创新理念以及观点在本文进行了阐述。  相似文献   
74.
OBJECTIVE: Recent reports suggest persistence of health disparities related to socio-economic position (SEP). To understand if diet may be a contributor to these trends, we examined secular trends in the association of diet and indicators of SEP from 1971-1975 to 1999-2002. DESIGN: We used data from the National Health and Nutrition Examination Surveys (NHANES) I (1971-1975), II (1976-1980), III (1988-1994) and 1999-2002 to examine the independent associations of poverty income ratio (PIR) and education with diet and biomarkers of diet and disease in 25-74-year-olds (n = 36,600). We used logistic and linear regression methods to adjust for multiple covariates and survey design to examine these associations. RESULTS: A large PIR differential in the likelihood of reporting a fruit or all five food groups and vitamin C intake, and an education differential in likelihood of obesity and carbohydrate intake, was noted in 1971-1975 but narrowed in 1999-2002 (P < 0.007). The positive association of education with intake of a fruit, vegetable or all five food groups, vitamins A and C, calcium and potassium intake remained unchanged across surveys (P < 0.001). Similarly, the positive association of PIR with the amount of foods and intakes of energy and potassium remained unchanged over three decades (P < 0.001). The education and the PIR differential in energy density, and the PIR differential in the likelihood of obesity, persisted over the period of the four surveys (P < 0.001). CONCLUSIONS: Persistence of unfavourable dietary and biomarker profiles in Americans with low income and education suggests continued need for improvement in the quality of diets of these high-risk groups.  相似文献   
75.
Genetic Resources and Crop Evolution - Crop breeding for abiotic stress tolerance entails introgression of stress tolerant genes into the cultivated types. With the augmentation in salt tolerance,...  相似文献   
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78.
  • ? In seasonally dry tropical forests deciduousness (leaflessness) is an important strategy of trees to survive in water stress period during summer. Deciduousness is a reflection of interacted effect of seasonal drought, tree characteristics and soil moisture conditions.
  • ? The present study aims to document the diversity in leaf pheno-phases in terms of duration of deciduousness (which is reciprocal to growing season length), wood density, leaf mass per area (LMA) and leaf strategy index in 24 important tree species growing in the Vindhyan dry tropical forest in India.
  • ? On the basis of phenological observations, the tree species were categorized into two main groups: leaf exchanging species exhibiting overlapping periods of leaf fall and leaf flush, and deciduous species whose timings of leaf flush and leaf fall differ resulting in a time lag (deciduousness) between the completion of leaf fall and initiation of leaf flush. Presence of wide range of deciduousness duration (from ca. a week to 7 months) among dry tropical trees indicates large variations in their growing season length. In the tree species studied, as the duration of deciduousness increased, leaf flushing period decreased significantly but leaf fall period showed little variation.
  • ? Differing deciduousness in tree species exhibited substantial differences in their leafing (vegetative growth) pattern, as reflected by ratio of durations of leaf flush to leaf fall (leaf strategy index). Across different species, duration of deciduousness was significantly positively correlated with leaf strategy index, and significantly negatively correlated with both wood density and LMA.
  • ? Wide variations in deciduousness, leaf strategy index, wood density and LMA in the 24 species investigated indicate considerable functional diversity in tree species growing in Vindhyan dry tropical region. Variation in seasonal duration of deciduousness among species is reflections of differences in tree functional traits like stem wood density, leaf strategy index and LMA.
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    79.
    Hexachlorocyclohexane (BHC) was fed at a 500-ppm-dose level in diet to pure inbred Swiss mice for 2, 4, 6, and 8 months. Later BHC was discontinued for 4 months and subsequently the animals were refed BHC for 1 month. The protein, lactate dehydrogenase (E.C.1.1.1.27), isocitrate dehydrogenase (E.C.1.1.1.42), and malate dehydrogenase (E.C.1.1.1.37) were studied from liver. The liver weight as percentage of body weight was also determined. The results showed an increase in the liver weight/body weight ratio and a decrease in protein and all three enzymes after BHC feeding for the different time intervals. The discontinuation of BHC in the diet resulted in the reversion of values of the above parameters toward the normal and after refeeding BHC for 1 month, the decreased values, as seen after initial BHC feeding, were again observed. This indicates that the changes in the values of lactate dehydrogenase, isocitrate dehydrogenase, and malate dehydrogenase are associated with hexachlorocyclohexane feeding in the diet. The significance of these changes is discussed.  相似文献   
    80.
    The present study on defined double deletion (ΔarohtrA) mutant (S30) of Salmonella enterica serovar Abortusequi evaluated it for safety, immunogenicity, and efficacy as a vaccine candidate in equids. The candidate strain was found safe in equids (foals, male and female horses and donkeys, and pregnant and nonpregnant mares) and induced good humoral and cell-mediated immunity on administration through oral route. The strain was not excreted in feces of vaccinated animals. The vaccine candidate administered orally (1 × 1011 cfu per animal) protected mares even after 180 days of inoculation against abortion on challenge with wild-type S. Abortusequi strain whereas in nonvaccinated control, all mares aborted. The vaccination in infertile mares resulted in regaining of fertility in 67%–80% thoroughbred mares at two different breeding farms. Further, the humoral immunity was transferred to foals from vaccinated mothers through colostrum, but no placental transfer was evident. Thus, the vaccine under study may be recommended for use in equids to control S. Abortusequi infection–associated abortions and also to enhance fertility of temporarily infertile mares in endemic areas.  相似文献   
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