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排序方式: 共有171条查询结果,搜索用时 359 毫秒
161.
Mohammad Shaheed Hossain Chowdhury Md. Mizanur Rahman Masao Koike Nur Muhammed Kazi Mohammad Salahuddin Md. Abdul Halim Narayan Saha Md. Parvez Rana Md. Jahirul Islam 《Small-Scale Forestry》2010,9(1):93-105
Throughout the world ornamentation of body with mehedi (Lawsonia inermis L.) leaf paste, with the trade name ‘henna body art’ is becoming increasingly popular. The worldwide increasing demand of
mehedi leaf encourages many countries to adopt commercial farming of the plant. Farmers living in central Bangladesh recently
commenced small-scale mehedi farming, primarily with the purpose of meeting national demand. A total of 182 farmers are engaged
in mehedi farming and a study was conducted among 36 of them (a 20% random sample) to explore indigenous management techniques,
marketing, livelihood potential and constraints of the enterprise. Farming was reported to be the major primary occupation
of the study area. An average of 0.05 ha land of the respondents was used for mehedi cultivation, which constituted 16.7%
of their average farm land. The farmers applied their own indigenous technology in every aspect of the farming, using branch
cuttings as the only propagation material. The financial analysis indicated that mehedi farming is a profitable and attractive
option for rural livelihoods [with an estimated net present value of Tk (Bangladeshi currency unit, 1 US $ = 68 Taka (as of
May, 2009).) 179,500 for 0.1 ha plantation]. However, the enterprise faces several constraints, including absence of a nursery
for supplying planting materials, storage and effective marketing facilities, available capital for investment, improved technology,
and above all, government support. If the government extends cooperation by assisting farmers with training, technology, credit
and market development, mehedi farming could become an important revenue-earning enterprise in the small-scale cottage sector
of Bangladesh. 相似文献
162.
Grain and stover yield are key traits for the improvement of rabi sorghum varieties and hybrids in India. Large genotype-by-environment interactions (GEI) were identified for both grain and stover yield based on 10 years’ data available from the All India Coordinated Sorghum Improvement Program (AICSIP) experiments conducted from 1986/87 to 1996/97. From the estimates of the genotypic, GEI and residual components of variance for the four traits, a multi-environment testing strategy based on 15–20 locations, 2–3 years, and two replicates per trial would be required to achieve estimates of repeatability of approximately 0.70 for grain yield, 0.45 for stover yield, 0.70 for flowering time, and 0.85 for plant height. 相似文献
163.
This paper describes the impact of rice hydraulic loading (percentage area under rice crop) on groundwater levels and salinity
in the Murrumbidgee irrigation area (MIA), Australia using a MODFLOW-based modelling approach. The model simulations show
that the groundwater levels will be in equilibrium after a fall of approximately 1 m under most of the areas, however, the
groundwater salinity levels will rise by more than 1,000 μs/cm in most parts of irrigation area. If the rice growing area
is reduced by 50 and 75%, there can be a net decline in groundwater levels during the first 2 years and then a new quasi-equilibrium
will be established. To downscale these results at the farm level, SWAGMAN Farm model in conjunction with groundwater outflow
rates obtained from a three-dimensional MODFLOW model was applied for determining net recharge rates under rice for different
areas within the MIA. The highest net recharge during 2005–2006 season was 0.84 ML/ha (84 mm) in parts of the irrigation system,
whereas the average net recharge due to rice hydraulic loading for the whole MIA during 2005–2006 season was estimated as
0.34 ML/ha (34 mm). 相似文献
164.
Sujata Misra Awadhesh Kumar Srivastava Sushma Verma Sudhakar Pandey Surendra Singh Bargali Tikam Singh Rana K. Narayanan Nair 《Genetic Resources and Crop Evolution》2017,64(5):995-1010
Genetic variations and relationships among cultivated and wild genotypes of five taxa of Indian Luffa were examined using inter simple sequence repeats (ISSR), directed amplification of minisatellite DNA (DAMD) markers and morphological characterization. Morphometric evaluation of 21 discrete characters in 51 representative accessions segregated the five taxa of Luffa in three main clusters: the two wild species (L. echinata, L. graveolens) in the first, and the cultivated L. aegyptiaca (smooth gourd) and L. acutangula (ridged gourd)/L. hermaphrodita (Hermaphrodite luffa) in the second and third clusters, respectively. Cumulative data analysis of 15 ISSR and seven DAMD markers revealed high percentage polymorphism (97.67 %), moderate genetic distance (0.06–0.72, avg. 0.51), and low heterozygosity and Shannon index values (H = 0.15; I = 0.22) across all the 76 genotypes assayed. A UPGMA dendrogram, based on the combined marker data, resolved the five taxa in two main clusters with high bootstrap support. The morphological and molecular trees showed incongruence in the number of main clusters resolved and in the disposition of the wild and cultivated taxa in different sub-clusters. The cluster analyses and PCoA plots revealed a nested grouping of the hermaphrodite luffa within the ridge gourd group. The Bayesian STRUCTURE analysis identified three genetic clusters for the five assumed taxa. Outcrossing test revealed a mixed mating system in Indian Luffa. This is the first ever report on the mating system in Luffa using molecular markers. The study also demonstrates the utility of using more than one DNA marker in the assessment of molecular diversity in a widely cultivated crop genus like Luffa with a narrow genetic base. 相似文献
165.
Rana Valizadeh Kamran Lamia Vojodi Mehrabani Mohammad Bagher Hassanpouraghdam 《Communications in Soil Science and Plant Analysis》2017,48(16):1852-1859
Salinity is one of the major environmental stressors which has deleterious effects on the growth, development, and yield of crops. Because of the gradual increase in soil and water salinity in the East Azarbaijan, Iran, Tanacetum balsamita L. cultivation in this region has always been associated with many problems. To study the effect of foliar spray of iron sulfate (FeSO4) (0, 750, and 1500 mg L?1) under sodium chloride (NaCl) salinity (0, 50, and 100 mM) on some physiological characteristics of Tanacetum balsamita L. plants, an experiment was conducted as a factorial based on complete randomized block design with three replications. Total soluble solids (TSS) and essential oil contents were significantly affected by the interaction effects of FeSO4 foliar application and salinity levels. The highest TSS and essential oil content were found in the plants under NaCl0 × FeSO4 1500 mg L?1 treatment combination. Leaf length, leaf fresh and dry weights were influenced by both Fe foliar application and salinity levels. Foliar application of iron (Fe) positively affected leaf length, leaves fresh and dry weights, root fresh and dry weights and peroxidase (POD) content, especially at 1500 mg L?1. Other traits such as leaf length, leaf fresh and dry weights, malondialdehyde (MDA), POD and catalase (CAT) contents were influenced by salinity levels. For POD, MDA, and CAT contents, the highest values were recorded with NaCl 50 and 100. The highest values of leaf length, leaf fresh and dry weights were found in the control plants. 相似文献
166.
167.
Sunny Ahmar Yungu Zhai Huibin Huang Kaidi Yu Muhammad Hafeez Ullah Khan Muhammad Shahid Rana Abdul Samad Shahid Ullah Khan Olalekan Amoo Chuchuan Fan Yongming Zhou 《作物学报(英文版)》2022,(1):67-74
Manipulation of flowering time to develop cultivars with desired maturity dates is fundamental in plant breeding.It is desirable to generate polyploid rapeseed(Brassica napus L.)germplasm with varying flowering time controlled by a few genes.In the present study,Bna SVP,a rapeseed homolog of the Arabidopsis SVP(Short Vegetative Phase)gene,was characterized and a set of mutants was developed using a CRISPR/Cas9-based gene-editing tool.A single construct targeting multiple sites was successfully applied to precisely mutate four copies of Bna SVP.The induced mutations in these copies were stably transmitted to subsequent generations.Homozygous mutants with loss-of-function alleles and free transgenic elements were generated across the four Bna SVP homologs.All mutant T1lines tested in two environments(summer and winter growing seasons)showed early-flowering phenotypes.The decrease in flowering time was correlated with the number of mutated Bna SVP alleles.The quadruple mutants showed the shortest flowering time,with a mean decrease of 40.6%–50.7%in length relative to the wild type under the two growth conditions.Our study demonstrates the quantitative involvement of Bna SVP copies in the regulation of flowering time and provides valuable resources for rapeseed breeding. 相似文献
168.
Purification of a Low Molecular Weight Fucoidan for SPECT Molecular Imaging of Myocardial Infarction
Pierre Saboural Frédéric Chaubet Francois Rouzet Faisal Al-Shoukr Rana Ben Azzouna Nadia Bouchemal Luc Picton Liliane Louedec Murielle Maire Lydia Rolland Guy Potier Dominique Le Guludec Didier Letourneur Cédric Chauvierre 《Marine drugs》2014,12(9):4851-4867
Fucoidans constitute a large family of sulfated polysaccharides with several biochemical properties. A commercial fucoidan from brown algae, containing low molecular weight polysaccharidic species constituted of l-fucose, uronic acids and sulfate groups, was simply treated here with calcium acetate solution. This treatment led to a purified fraction with a yield of 45%. The physicochemical characterizations of the purified fucoidan using colorimetric assay, MALLS, dRI, FT-IR, NMR, exhibited molecular weight distributions and chemical profiles similar for both fucoidans whereas the sulfate and l-fucose contents increased by 16% and 71%, respectively. The biodistribution study in rat of both compounds labeled with 99mTc evidenced a predominant renal elimination of the purified fucoidan, but the crude fucoidan was mainly retained in liver and spleen. In rat myocardial ischemia-reperfusion, we then demonstrated the better efficiency of the purified fucoidan. This purified sulfated polysaccharide appears promising for the development of molecular imaging in acute coronary syndrome. 相似文献
169.
The ammonia flux from a green manured field was measured at a site in southern Italy. The green manure was provided by ploughing in about 66 and 78 t ha−1 of broad beans at the flowering stage during the spring in 1995 and 1996. The NH3 flux was estimated by means of the micrometeorological simplified aerodynamic method with the ammonia concentration measured at two levels above soil surface. Ammonia concentration was measured over a 2–3 h sampling period by trapping air NH3 in a H2SO4 solution and analysing this sample in the laboratory with the colorimetric method using the Nessler solution. About 70% of the total amount of ammonia was emitted in the first two days immediately after manuring. The NH3 flux was regulated by the same mechanism as the water vapour transport. Seventy percent of the daily ammonia was emitted around noon. The ammonia emission stopped during rainy and cold days and started again as soon as solar radiation, soil and air temperature increased, following plant decomposition. The total amount of ammonia emitted in the experimental period (28 days in 1995 and 18 days in 1996) was about 13 kg ha−1 for both years. 相似文献
170.
Hem Lata Akhilesh Sharma Hament Thakur Alisha Thakur Ranbir Singh Rana Manpreet Kaur 《Plant Breeding》2023,142(4):547-562
Fourteen genetically diverse inbred lines comprising of four genic male sterile lines and 10 often pollinated lines as testers were crossed following ‘line × tester’ mating design to generate 40 F1s. These F1s, parents and check ‘CH-27’ were evaluated in α-lattice square design, replicated thrice during summer seasons of 2020 and 2021. The male sterile line DPChMS 9-2 was good general combiner for marketable fruit yield and eight other component traits while testers namely, DPCh 10, PBC 535, VVG, Him Palam Mirch-2 and DPCh 40 showed significant GCA for majority of yield related traits. The hybrids DPChMS 9-2 × HPM-2, DPChMS 9-2 × DPCh 40, DPChMS 9-2 × DPCh 101, DPChMS 9-2× VVG and DPChMS 26-1× HPM-1 were the most desirable based on specific combining ability (SCA) and economic heterosis for fruit yield and other important traits. Heterosis was positively correlated with SCA indicating prediction of potential hybrids can be made based on both these parameters simultaneously. Present study provides an opportunity to exploit top hybrids for stability and commercial cultivation. 相似文献