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61.
Society in Bangladesh has specific gender roles with strong values and norms in which women are controlled and protected by men. Certain deviations degrade the women socially and trap them into prostitution. This paper investigates the situation of prostitutes in Bangladesh through analysis of the environment at their place of origin that instigated them into the present situation. The paper describes the present environment of the prostitutes in Narayanganj, identifies their spatial connectivity through determining their activity space and sphere of influence and makes some brief remarks about the old age situation of these prostitutes.  相似文献   
62.
Understanding the volatile profile of melon is an ever increasingly important task for breeders for enhancing their flavour component. For this purpose, F1 progeny and parental lines were analysed using headspace-solid phase microextraction gas chromatography–mass spectrometry-based analysis. Diallel analysis showed that most of the investigated compounds were controlled via non-additive genetic effects with general combining ability to specific combining ability ratios of less than 0.4. High heterosis results were observed in alcohols such as ethanol and octanol in both rind and mesocarp samples and benzylalcohol in the rind. It was also noted that the ester-based compounds with high heterosis values in mesocarp samples differed from those with heterosis in rind samples. These observations further emphasize the non-additive control of these compounds. It can be concluded that non-additive genetic control is strongly governing the genetic profile within the studied progeny. This finding indicated that dudaim lines as a valuable genetic material enhanced the volatile profile of odourless commercial types of ameri and inodorus melon.  相似文献   
63.
In this study saffron biomass partitioning was investigated in the research station of the Saffron Research Group, University of Birjand, Iran during 2009 - 2010. Plant sampling was done 25 times during the crop growth cycle. In each sampling date, the amounts of corm dry weight, root dry weight, root length, leaf dry weight, leaf area, bud number, bud dry weight (nodes on the surface of the corm), and flower weight were measured. Finally, different regression models were tested for predicting biomass partitioning in saffron. The cubic polynomial model was found to be the best for predicting biomass changes in most saffron organs (R 2 = ~74%). Total corm dry weight showed a decreasing trend up to the 120th day of plant growth and then increased until the end of the life cycle (mid-May). However, different trends were observed for root and leaf dry weights. Root and leaf dry weight increased up to the 120th and 150th day of the plant growth cycle, respectively, followed then by decreasing trends. Therefore, in the early growing season, leaves and root systems were developed using mother corms reservoirs, but at the end of the growth cycle replacement corms were grown by translocation of reservoirs from other saffron organs. In addition, the number and dry weight of buds had increasing trends during 160 days of measurement from the beginning of the growing season. The total length of roots and leaf area increased up to the middle of the growth cycle (Feb. 10) and then decreased. Moreover, saffron flower yield showed a rapid increasing trend in the first phase of the flowering period and then declined with a slower trend during the second flowering phase.  相似文献   
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Crop salt tolerance (ST) is a complex trait affected by numerous genetic and non‐genetic factors, and its improvement via conventional breeding has been slow. Recent advancements in biotechnology have led to the development of more efficient selection tools to substitute phenotype‐based selection systems. Molecular markers associated with genes or quantitative trait loci (QTLs) affecting important traits are identified, which could be used as indirect selection criteria to improve breeding efficiency via marker‐assisted selection (MAS). While the use of MAS for manipulating simple traits has been streamlined in many plant breeding programmes, MAS for improving complex traits seems to be at infancy stage. Numerous QTLs have been reported for ST in different crop species; however, few commercial cultivars or breeding lines with improved ST have been developed via MAS. We review genes and QTLs identified with positive effects on ST in different plant species and discuss the prospects for developing crop ST via MAS. With the current advances in marker technology and a better handling of genotype by environment interaction effects, the utility of MAS for breeding for ST will gain momentum.  相似文献   
67.
Abstract: Based on the thesis of ‘deagrarianisation’ of farming economies, work on sustainable rural livelihoods (SRL) has successfully captured the agency of rural producers as they diversify their livelihoods to minimise risk. SRL captures a complex interplay of local and global factors, as well as the synergies emanating from natural (environmental), economic and social capital that underpin diversification. The framework has been found useful for analyses of change in coastal, marine‐based livelihoods. However, agency at the local level implies equal power to accept and reject development interventions. The way groups diversify or use the options open to them depends as much on access to resources (the means), as on how that access is interpreted (the meaning), and the latter dimension is a creative (unpredictable) one. New introduced forms of economic activities, in this case seaweed farming, can be assigned meaning by participants that were unanticipated by change agents. Livelihood diversification through seaweed cultivation on Banggi island off Kudat, northern Sabah (East Malaysia) is not attained by economic factors alone but also by the meaning attached to the activity.  相似文献   
68.
This research was conducted to investigate the effect of natural zeolite on vegetative growth and flower characteristics of tuberose (Polianthes tuberosa L.). The experiment was performed as a completely randomized design with seven treatments (5, 10, 15, 20, 25 and 30 g zeolite/kg soil mixture along with control) and four replicates. Results indicate that zeolite increased the height of flowering stem, diameter of flower, leaf area and chlorophyll content, but decreased the diameter of flowering stem, dry weight of shoots, and roots and bulblets. Overall, zeolite added to the soil mixture had beneficial effects on only some of the parameters of tuberose growth and development.  相似文献   
69.
This study attempted to characterize the spatial distributions of soil pH and electrical conductivity (ECe) of coastal fields in the Miyandoroud region, northern Iran, for three soil layer depths by assessing spatial variability and comparing different interpolation techniques such as inverse distance weighting (IDW), ordinary kriging (OK), and conditional simulations (CS). Three soil composite samples were collected from 0–50, 50–100, and 100–150 cm depths at 105 sampling sites. At all three soil depths, pH and ECe were best fitted by exponential and spherical models, respectively. Nugget effects were higher for soil ECe data sets compared with soil pH at all three soil depths showing soil ECe had a spatial variability in small distances. The prediction accuracy of the interpolation methods indicated that the minimum error for all data sets was achieved with the OK method, except for pH at 50–100 cm depth, and the CS technique revealed the largest error. The effect of different numbers of simulations (100, 500 and 1000) in the CS interpolation method resulted not in a realistic mapping for the soil ECe and pH. Considering the high importance of irrigated agriculture in the Caspian Sea coastal areas, more subsoil salinity build-up and groundwater salinity monitoring plans are needed as a prerequisite for sustainable agricultural production systems of the future.  相似文献   
70.
An experiment was conducted to study the effect of organic manure and chemical fertilizers on soil properties and vegetable crops in the cabbage-brinjal-red amaranth cropping pattern at the homestead in a Grey Terrace Soil (Aric Albaquept) of Bangladesh. There were eight treatments: poultry manure (PM) at 5 t ha?1, cowdung (CD) at 10 t ha?1, household waste (HW) at 10 t ha?1, PM at 2.5 t ha?1 + chemical fertilizers (CF), CD at 5 t ha?1 + CF, HW at 5 t ha?1 + CF, CF, and Control. The lone CF treatment indicates 100% chemical fertilizers and any manure + CF indicates supplementary or reduced rate of fertilizers. The PM at 2.5 t ha?1 + CF treatment performed the best yield for cabbage and brinjal, and HW at 5 t ha?1 + CF yielded the highest for red amaranth. The highest uptake of nitrogen, phosphorus, potassium, and sulfur was also found in the treatment that produced the highest yield. Bulk density, organic carbon, and nutrient availability in soil as determined after two-crop cycles were improved due to the applications of manure.  相似文献   
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