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71.
Only a little is known about the studies done with filariasis in relation to blood groups. The present communication reports the results of a preliminary study carried out to investigate any relationship of ABO and Rho(D) blood groups in persons with circulating microfilariae (mf) in blood and with disease manifestations compared with healthy normal controls within a population in similar epidemiological and ecological conditions. Blood groups ABO and Rho(D) were investigated among 271 persons with filarial disease and 172 normal subjects from an endemic area of bancroftian filariasis. No relationship was observed between infection and blood groups. It appeared that blood groups and filarial infection were independent of each other. Also the sex of the individual and stage of the infection, i.e. persons with circulating mf only without manifestations and persons with established manifestation without mf, has no bearing on blood group inheritance. There were 95.05% of Rh-positive and 4.95% of Rh-negative persons in the whole studied population. The observations are similar to other studies. 相似文献
72.
Aditya Pratap Umashanker Prajapati Chandra Mohan Singh Sanjeev Gupta Meenal Rathore Nupur Malviya Rakhi Tomar Ajeet Kumar Gupta Swapnila Tripathi Narendra Pratap Singh 《Plant Breeding》2018,137(3):235-249
Grain legumes, the important constituents of sustainability‐based cropping systems and energy‐limited vegetarian diets have long been the subject of scientific research. Tremendous technological strides were made in the so‐called orphan crops, in terms of both varietal improvement and generation of basic information. Despite recalcitrancy and high genotype dependency, in vitro culture techniques such as organogenesis, in vitro mutagenesis, embryo rescue and in vitro gene transfer have been deployed for improvement of several grain legumes and these played an important role in introgression of desirable genes from related and distant species and creation of additional genetic variability. Stable and reproducible regeneration protocols resulted in the development of genetically modified chickpea, pigeon pea, cowpea, mungbean, etc., while embryo rescue was deployed successfully for recovery of interspecific recombinants, a few of them exploited for the development of commercial cultivars. Nevertheless, doubled haploidy witnessed limited success and protoplast regeneration and in vitro mutagenesis remained of academic interest. The present review focuses on the progress, achievements, constraints and perspectives of using in vitro technology in grain legume improvement. 相似文献
73.
Effect of different biofloc system on water quality,biofloc composition and growth performance in Litopenaeus vannamei (Boone, 1931) 下载免费PDF全文
Muthusamy Rajkumar Pramod Kumar Pandey Radhakrishnapillai Aravind Alagarsamy Vennila Vivekanand Bharti Chandra Sekharan Purushothaman 《Aquaculture Research》2016,47(11):3432-3444
The experiment was conducted with three biofloc treatments and one control in triplicate in 500 L capacity indoor tanks. Biofloc tanks, filled with 350 L of water, were fed with sugarcane molasses (BFTS), tapioca flour (BFTT), wheat flour (BFTW) and clean water as control without biofloc and allowed to stand for 30 days. The postlarvae of Litopenaeus vannamei (Boone, 1931) with an Average body weight of 0.15 ± 0.02 g were stocked at the rate of 130 PL m?2 and cultured for a period of 60 days fed with pelleted feed at the rate of 1.5% of biomass. The total suspended solids (TSS) level was maintained at around 500 mg L?1 in BFT tanks. The addition of carbohydrate significantly reduced the total ammonia‐N (TAN), nitrite‐N and nitrate‐N in water and it significantly increased the total heterotrophic bacteria (THB) population in the biofloc treatments. There was a significant difference in the final average body weight (8.49 ± 0.09 g) in the wheat flour treatment (BFTW) than those treatment and control group of the shrimp. Survival of the shrimps was not affected by the treatments and ranged between 82.02% and 90.3%. The proximate and chemical composition of biofloc and proximate composition of the shrimp was significantly different between the biofloc treatments and control. Tintinids, ciliates, copepods, cyanobacteria and nematodes were identified in all the biofloc treatments, nematodes being the most dominant group of organisms in the biofloc. It could be concluded that the use of wheat flour (BFTW) effectively enhanced the biofloc production and contributed towards better water quality which resulted in higher production of shrimp. 相似文献
74.
Shailendra Kumar Yadav U. U. Khokhar Som Dev Sharma Pramod Kumar 《Journal of plant nutrition》2016,39(2):194-203
The aim of this research was designed in order to optimize integrated plant nutrient supply (IPNS) through balanced fertilization of organic, inorganic and microbial inoculants in strawberry cv. Chandler. The potential efficiency of bio-organics used along with chemical fertilizers on cropping behaviour, physical-chemical and biological properties of rhizosphere soil, fruit yield, quality attributes and leaf nutrient content was investigated. The significant improvement in physico-chemical properties of the soil and nutrient uptake was recorded. The uninoculated control received farmyard manure (FYM) and inorganic nitrogen (N) recorded the highest cation exchange capacity (CEC) and soil organic carbon (OC) content. Highest available N and phosphorus (P) of soil were recorded in vermicompost and inorganic N applied in two and one split, respectively. The concentration of micronutrients cations viz., iron (Fe), zinc (Zn), manganese (Mn) in soil was higher in treatment received vermicompost and inorganic N in two splits. The integration of bio-organic nutrient supplements also significantly enriched the microbial status of the rhizosphere soil, leaf nutrient concentration and maintained soil health and productivity on long term basis for sustainable fruit production. 相似文献
75.
Exploring genetic diversity for heat tolerance among lentil (Lens culinaris Medik.) genotypes of variant habitats by simple sequence repeat markers 下载免费PDF全文
Dharmendra Singh Chandan K. Singh Ram Sevak S. Tomar Ashish K. Chaturvedi Divya Shah Arun Kumar Madan Pal 《Plant Breeding》2016,135(2):215-223
The study was carried out to assess genetic diversity among 119 lentil genotypes grown in different habitats for heat tolerance using morpho‐physiological and reproductive traits and SSR markers. High‐temperature stress was applied at seedling (35/33°C) and anthesis stages (35/20°C) to study the effects on morpho‐physiological and reproductive traits under hydroponic condition, which was compared with non‐stressed and stressed field conditions. A set of 209 alleles were identified by 35 SSR markers among the genotypes. Genetic diversity and polymorphism information content values varied between 0.0494–0.859 and 0.0488–0.844, with mean values of 0.606 and 0.563, respectively. Genotypes were clustered into nine groups based on SSR markers. Morpho‐physiological and reproductive traits under heat stress were found to be significantly different among SSR clusters. These findings suggest that heat adaptation is variable among the genotypes and the tolerant materials can be evolved through hybridization using parents from different clusters with diverse mechanisms of heat tolerance. 相似文献
76.
Kwasi Bannor Richard Amarnath Krishna Kumar Gupta Oppong-Kyeremeh Helena Abawiera Wongnaa Camillus 《水稻科学》2020,27(1):56-66
The factors affecting the adoption of modern varieties(MVs) of rice and impact on poverty in Odisha, India were discussed. A total of 363 households from Cuttack and Sambalpur districts of Odisha via multistage sampling technique participated in the survey. The Cragg's Double hurdle model was used to model the determinants of adoption and intensity of adoption of MVs of rice, and the propensity score matching was used to analyze the impact of adoption on poverty. The results showed that age, education, risk aversion, land size, yield, perception of MVs as high yielding, resistant to diseases and availability of MVs positively influenced the decision to adopt. However, variables such as household size, experience of a farmer, off-farm job participation, amount of credit received, cost of seeds, insecticides and fertilizers negatively influenced the adoption of MVs. Intensity of adoption of MVs was negatively influenced by experience of a farmer, cost of fertilizer and marketability of MVs, and positively affected by household size, risk aversion, land size, cost of insecticides, perception of MVs as high yielding and availability of MV seeds. Poverty incidence, gap and severity were high among non-adopters to adopters of MVs. After matching adopters and non-adopters of MV groups using four different algorithms of nearest neighbour matching, stratification matching, radius matching and kernel matching, the impact of MV adoption resulted in higher per capita monthly household expenditure by about US$ 52.82 to US$ 63.17. 相似文献
77.
L. S. Rao P. Usha Rani P. S. Deshmukh P. A. Kumar S. K. Panguluri 《Genetic Resources and Crop Evolution》2007,54(6):1235-1244
Detection of genetic relationships between 19 chickpea cultivars and five accessions of its wild progenitor Cicer reticulatum Ladizinsky were investigated by using RAPD and ISSR markers. On an average, six bands per primer were observed in RAPD analysis
and 11 bands per primer in ISSR analysis. In RAPD, the wild accessions shared 77.8% polymorphic bands with chickpea cultivars,
whereas they shared 79.6% polymorphic bands in ISSR analysis. In RAPD analysis 51.7% and 50.5% polymorphic bands were observed
among wild accessions and chickpea cultivars, respectively. Similarly, 65.63% and 56.25% polymorphic bands were found in ISSR
analysis. The dendrogram developed by pooling the data of RAPD and ISSR analysis revealed that the wild accessions and the
ICCV lines showed similar pattern with the dendrogram of RAPD analysis. The ISSR analysis clearly indicated that even with
six polymorphic primers, reliable estimation of genetic diversity could be obtained, while nearly 30 primers are required
for RAPD. Moreover, RAPD can cause genotyping errors due to competition in the amplification of all RAPD fragments. The markers
generated by ISSR and RAPD assays can provide practical information for the management of genetic resources. For the selection
of good parental material in breeding programs the genetic data produced through ISSR can be used to correlate with the relationship
measures based on pedigree data and morphological traits to minimize the individual inaccuracies in chickpea. 相似文献
78.
Tarik Mitran Pabitra Kumar Mani Nirmalendu Basak Debasis Mazumder Manabendra Roy 《Archives of Agronomy and Soil Science》2016,62(1):1-18
A study on the rice–wheat cropping system was conducted at Bidhan Chandra Krishi Viswavidyalaya, West Bengal, India, to assess the effects of long-term manuring and fertilization on transformation of the inorganic phosphorus (P) fraction in soil after 22 years of the crop cycle. Soil samples were collected after Kharif from seven treated plots having different types of organic amendments like farm yard manure, paddy straw and green manuring with 50% substitution of nitrogen levels in rice crop only. The result showed that the yield trend of rice was maintained due to the buildup of P from various organic inputs. Although cultivation for 22 years without adding any fertilizer caused a significant decrease in almost all the forms of P viz. avail-P, saloid P, iron phosphorus fraction (Fe–P), aluminum phosphorus fraction (Al–P), calcium phosphorus fraction (Ca–P) and total P in control. Partial substitution of inorganic fertilizer N (50%) with organics, however, caused a significant increase in almost all the P fractions in soil over the control. The relative abundance of all the fractions of inorganic P irrespective of treatments was as follows: Fe–P > reductant soluble P fraction > occluded P > Al–P > Ca–P > saloid P. Saloid and Fe–P were the dominating fractions responsible for 92% variation of available P and total P levels, respectively. 相似文献
79.
Fijian adolescents’ understanding and evaluation of climate change: Implications for enabling effective future adaptation 下载免费PDF全文
Pacific Island countries are particularly vulnerable to future manifestations of climate change due to high coastline‐to‐land‐area ratios, and high dependence of inhabitants on natural ecosystems. While everyone in the Pacific Islands should participate in climate change adaptation activities, it is the young people, given they are the generation likely to not only bear the burden of climate change, but to lead and live effective climate change adaptation activities and strategies specific to their region, the involvement of youth is critical. Pacific Island youths are often marginalised within traditional decision‐making hierarchies, therefore they are typically excluded from participating in meaningful discussions at community and government levels. Discussions were held with 30 adolescents aged 14–18 years in Fiji to explore knowledge and experiences regarding climate change. Participants revealed their dismay at their inability to talk to family – who they consider are not doing enough – about what they consider as appropriate responses to climate change, recommending the help of an authoritative outsider who could speak to their community leaders and family. Discussions also revealed that Fijian youth could not distinguish between changes in the climate and normal weather events, attesting to the importance of climate‐change education and awareness‐raising efforts within the Pacific Islands more generally. 相似文献
80.
Diploid wheat (Triticum monococcum L, AmAm) is an ideal material for induced mutations which can be easily characterized and transferred to polyploid wheats. The EMS-induced brittle culm mutants, brc1, brc2, and brc3 used in the present investigation, were isolated from T. monococcum. All the brittle mutants had brittle roots, leaves, leaf sheaths, culms, and spikes, and were also susceptible to lodging. The mutants had 47–57% reduced α-cellulose in the secondary cell walls than that of T. monococcum indicating that all of them had defective synthesis of cellulose. All the mutants were monogenic recessive. Bulk segregation analysis of the mutants, using Am genome anchored SSR markers in their F 2 populations with T. boeoticum, located the mutants, brc1, brc2, and brc3 on chromosome 6A, 3A, and 1A of T. monococcum, respectively. Molecular analysis of the putatively linked markers showed that brc1 mapped on chromosome 6AS between Xbarc37 and Xbarc113 markers, brc2 on chromosome 3AL between Xcfd62 and Xcfa2170 markers whereas brc3 mapped on chromosome 1AL between Xgwm135 and Xwmc470 markers. Isolation and mapping of three different brittle culm mutants in wheat for the first time shows that there might be many more genes in wheat which affect synthesis and deposition of cellulose. 相似文献