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931.
N(1)- and N(3)-(4-fluorophenyl) ureas (III a-e) were cyclocondensed with ethyl chloroformate and CS(2)/KOH to yield 2-aryl-6-(4-fluorophenyl)-1,3,4-oxadiazolo[3,2-a]-s-triazine-5, 7-diones (IVa-e) and their 5-thioxo-7-ones (Va-e), respectively. The compounds III-V(a-e) have been compared with Dithane M-45 for their fungitoxic action against A. niger and F. oxyporum, and the results have been correlated with the structural features of the tested compounds. 相似文献
932.
Tayyaba Sultana Abdul Ghafoor Muhammad Ashraf 《Genetic Resources and Crop Evolution》2007,54(6):1159-1165
Variation in bread wheat including pre and post green revolutions varieties of Pakistan along with landraces was investigated
for high molecular weight Glutenin subunits (HMW Gs) encoded at three genes (Glu-A1, Glu-B1, Glu-D1) with SDS-PAGE. The germplasm was diverse and unique on the basis of HMW Gs compositions and out of 14 alleles detected at
all the Glu-1 loci, three belonged to Glu-A1, nine to Glu-B1 and two to Glu-D1 locus. High variation was observed in the landraces and higher gene diversity was observed between the populations as compared
to the gene diversity within populations, whereas a reverse pattern of gene diversity was observed when populations were pooled
across the region (higher within the regions than between the regions). A lack of relationship between the HMW Gs diversity
and the altitude of collection site was observed. A data base has been generated in this study which could be expanded/exploited
for cultivar development or management of gene bank. 相似文献
933.
Md. Sarwar?Jahan Yuji?Uemura Toshihiro?Kumamaru Abdul?Hamid Hikaru?SatohEmail author 《Genetic Resources and Crop Evolution》2005,52(8):977-987
Bangladesh rice genetic resources collected from six distinct regions of the country were examined to obtain the diversity
in glutelin acidic subunit polypeptides. Seed glutelins from 576 Bangladesh rice cultivars representing seven ecotypes were
analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), isoelectric focusing (IEF) electrophoresis
and two-dimensional electrophoresis (2-DE: SDS-PAGE/IEF) analyses. Glutelin acidic subunit was separated into four bands,
α-1, α-2, α-3 and α-4, and the variation in each of bands was detected by SDS-PAGE analysis. A higher molecular size component of α-1(α-1′) was identified in the cultivars tested. In case of α-2, α-2H with high molecular mass, α-2L with low molecular mass and α-2H/L were detected. α-3 band variation showed α-3H, α-3L, and α-3H/L, while for α-4, α-4H, α-4L bands were identified. In IEF analysis, a total of 16 bands with independent pI ranging from pI 6.30 to 7.52 were identified for the glutelin acidic subunit among the cultivars. The maximum and minimum numbers of IEF
bands found were 13 and 9, respectively. The α-2L less cultivars were also lacking in pI 6.80 polypeptide in IEF. Result of 2-DE showed that pI 6.80 polypeptide was the main component of α-2L band. Transplanted Aman ecotype was the most diverse with respect to glutelin variation. Geographical distribution of
glutelin variation in the Transplanted Aman ecotype differed according to the regions. The above results indicate that Bangladesh
rice cultivars possess great genetic diversity in glutelin acidic subunit polypeptides. This study of indigenous rice cultivars
from Bangladesh provides useful information regarding their breeding potential. 相似文献
934.
In a survey of nonhost plant secondary metabolites regulating motility and viability of zoospores of the Aphanomyces cochlioides, we found that stem bark extracts of Lannea coromandelica remarkably inhibited motility of zoospores followed by lysis. Bioassay-guided fractionation and chemical characterization of Lannea extracts by MALDI-TOF-MS revealed that the active constituents were angular type polyflavonoid tannins. Commercial polyflavonoid tannins, Quebracho and Mimosa, also showed identical zoosporicidal activity. Against zoospores, the motility-inhibiting and lytic activities were more pronounced in Lannea extracts (MIC 0.1 microg/mL) than in Quebracho (MIC 0.5 microg/mL) and Mimosa (MIC 0.5 microg/mL). Scanning electron microscopic observation visualized that both Lannea and commercial tannins caused lysis of cell membrane followed by fragmentation of cellular materials. Naturally occurring polyflavonoid tannin merits further study as potential zoospore regulating agent or as lead compound. To the best of our knowledge, this is the first report of zoosporicidal activity of natural polyflavonoid tannins against an oomycete phytopathogen. 相似文献
935.
Kahar Priyadi Abdul Hadi Tiusbul H. Siagian Chatimatun Nisa Aulia Azizah Nilly Raihani Kazuyuki Inubushi 《Soil Science and Plant Nutrition》2005,51(5):689-691
A field experiment was carried out to elucidate the effect of chicken manure (CM) and effective microorganisms (EM) on the yield of corn and chemical and microbial properties of acidic wetland soils. A split-split plot experimental design with three replications was used in this research. The main plot consisted of two types of soil. The sub-plot was for the application of CM, while the sub-sub plot was for the application of EM. Sweet corn seeds were planted and cultivated until harvest. Above ground plant biomass and round of the stem of an ear of corn were observed. Soil samples were taken and analyzed for chemical and microbial properties. The results showed that the interaction between soil types and CM application affected the corn yield, while EM had no effect. Similarly, the chemical and microbial characteristics of soils used were affected by soil type and the application of CM, while the effect of EM was not clear. 相似文献
936.
Zulfiqar Ahmad Shermeen Tahir Abdul Rehman Nabeel Khan Niazi Muhammad Abid Muhammad Amanullah 《Journal of plant nutrition》2015,38(12):1913-1928
The potential of encapsulated calcium carbide (ECC) in improving growth, yield and physiology of cotton under salinity was evaluated in pot experiment. Salinity was induced by sodium chloride (NaCl) at 0, 1250 and 2000 ppm. The ECC was applied at the rate of 0, 15, and 30 mg kg?1 soil. The results revealed that ECC improved number of branches, yield, shoot dry biomass, root dry biomass, by 57, 67, 40, 22, and 18% respectively, over control. Similarly, net photosynthesis, stomatal conductance nitrogen, phosphorus and potassium (N, P and K) concentration of shoot were enhanced by 38, 34, 7, 25 and 11% over control, respectively. The induction of new set of proteins ranging from 11 to 26 kDa was also observed at various levels of ECC and salinity stress. These results proved the efficacy of very lower concentrations of ethylene produced by ECC and showed the behavior of different parameters of cotton to it under saline stress. 相似文献
937.
Mohammed Abu Sayed Arfin Khan Fahmida Sultana Md. Habibur Rahman Bishwajit Roy Sawon Istiak Anik 《林业研究》2011,22(4):649-658
Species diversity and ethno-medicinal usage of 39 species of invasive plants were explored in and around two protected areas, Khadimnagar National Park (KNP) and Rema-Kalenga Wildlife Sanctu- ary (RKWS), of northeastern Bangladesh,. Status of invasive plants were investigated in 60 sample plots with 5 different habitat types, including forest, roadside, homestead, fallow land and others (ponds, canals, water logged areas, agricultural land, etc.). Data about the usage of invasive plants in traditional health care were collected through interviewing 110 households. Among the five habitat types, fallow land (28 species) pos- sessed the highest number of species, followed by roadside (25 species), forest (23 species), homestead (22 species) and others (13 species). Based on the survey, invasive plants of study areas were also categorized into five degrees of invasiveness e.g., naturalized, introduced, possibly invasive, moderately invasive and highly invasive. Additionally, there is the linear trend between degrees of invasiveness and use percentage of invasive plants. Total 39 species of invasive plants belonging to 29 fami- lies were recorded, which are generally used to treat 37 diseases, ranging from simple headache to highly complicated eye and heart diseases. The majority of the species used by the local inhabitants were herbs (16 spe- cies), followed by some shrubs (11 species), climbers (5 species), trees (5 species) and grasses (2 species). The use percentage of aboveground plant parts were higher (70.58%) than that of underground plant parts (16.18%). 相似文献
938.
Sajid Hussain Muhammad Maqsood Muhammad Ijaz Abdul Sattar Ahmad Sher 《Journal of plant nutrition》2020,43(14):2214-2225
AbstractMaize (Zea mays L.) plays an important role in the global food security, but its production is threatened by climate change, especially drought stress. Potassium (K) and zinc (Zn) are considered useful to mitigate the negative consequences of drought stress in plants. Therefore, the objective of this two-year study was to identify the best combination of K and Zn application to improve the water relations, photosynthetic pigments, yield, irrigation water use efficiency (IWUE) and grain quality of maize sown under mild and severe drought stress conditions. The consisted of three drought stress levels viz. 1) well-watered as control (WW), 2) mild drought (MD) with 25?mm of potential soil moisture deficit (PSMD), 3) severe drought (SD) with 50?mm of PSMD and six K-Zn treatments: i.e. 125, 100 and 150?kg ha?1 K with 0 and 12?kg ha?1 Zn. The results indicated that K-Zn application improved the water relations and chlorophyll contents, biological yield and grain quality, irrespective of water stress treatment. The combined application of K-Zn under mild drought stress produced statistically same biological yield and grain quality as under well-irrigated without K-Zn fertilization and also produced compratively higher IWUE, biological yield and grain quality under sverer drought stress. Hence, the application of K at 150?kg ha?1 in combination with Zn at 12?kg ha?1 might be useful to improve the maize production and grain quality under drought stress. As IWUE was low in WW conditions, therefore, irrigation scheduling must be re-evaluated for optimum water use efficiency. 相似文献
939.
Md. Saiful ISLAM Md. Kawser AHMED Md. Habibullah Al-MAMUN Dennis Wayne EATON 《土壤圈》2020,30(2):201-213
Trace metal contamination in soil is of great concern owing to its long persistence in the environment and toxicity to humans and other organisms.Concentrations of six potentially toxic trace metals,Cr,Ni,Cu,As,Cd,and Pb,in urban soils were measured in Dhaka City,Bangladesh.Soils from different land-use types,namely,agricultural field,park,playground,petrol station,metal workshop,brick field,burning sites,disposal sites of household waste,garment waste,electronic waste,and tannery wast,and construction waste demolishing sites,were investigated.The concentration ranges of Cr,Ni,Cu,As,Pb,and Cd in soils were 2.4–1258,8.3–1044,9.7–823,8.7–277,1.8–80,and 13–842 mg kg^-1,respectively.The concentrations of metals were subsequently used to establish hazard quotients(HQs)for the adult population.The metal HQs decreased in the order of As>Cr>Pb>Cd>Ni>Cu.Ingestion was the most vital exposure pathway of studied metals from soils followed by dermal contact and inhalation.The range of pollution load index(PLI)was 0.96–17,indicating severe contamination of soil by trace metals.Considering the comprehensive potential ecological risk(PER),soils from all land-use types showed considerable to very high ecological risks.The findings of this study revealed that in the urban area studied,soils of some land-use types were severely contaminated with trace metals.Thus,it is suggested that more attention should be paid to the potential health risks to the local inhabitants and ecological risk to the surrounding ecosystems. 相似文献
940.