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Comparative evaluation of sunflower aqueous extracts and commercially available synthetic herbicides was carried out in field trials. Crude aqueous extract was tested in 80 and 100% concentrations in plots where wheat was grown with Rumex dentatus in a 1:1 mix. In comparison with the synthetic herbicides (Buctril-Super® and Chwastox®) the aqueous extract failed to kill 100% of selected weeds, but the highest tested extract concentration completely overcame weed crop competition by reducing the weed biomass and increasing wheat yield significantly. The trial confirmed the herbicidal potential of sunflower allelochemicals against broad leaf weeds.  相似文献   
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An efficient regeneration protocol for rapid mass propagation and uptake of heavy metals in Albizia lebbeck (L.), a fast growing, medicinally as well as economically important timber yielding tree was developed. Nodal segments derived from a 20-year-old tree were cultured on MS (Murashige and Skoog) medium supplemented with 10 μM 6-Benzyladenine (BA) and 1 μM α-Naphthalene acetic acid (NAA) showed optimum shoot regeneration frequency (76.6%), number of shoots (23.2 ± 0.28) per explant and shoot length (2.86 ± 0.08 cm) after 10 weeks of culture. After standardizing a reliable protocol for micropropagation, effects of ZnSO4 (0.06–0.48 mM), CuSO4 (0.02–0.2 mM) and CdCl2 (0.0001–0.001 mM) on shoot morphogenesis were also assessed. The regenerated shoots maintained on maintenance medium (MS + 10.0 μM BA + 1.0 μM NAA) containing ZnSO4 (0.06 mM) showed maximum response in terms of shoot number (24.5 ± 0.83) and length (5.9 ± 0.05 cm) after 10 weeks of culture. Proline content showed an increasing trend while chlorophyll (a and b) content exhibited decreasing trend with an increased metal concentrations compared to MM cultures, and maximum increase in proline and decrease in chlorophyll content was recorded in cultures grown on Cd-enriched medium. Best rooting was accomplished on half strength MS medium with 2.0 μM IBA and ZnSO4 (0.06 mM). The plantlets thus obtained were successfully hardened and transferred to greenhouse with 75% survival rate and exhibited normal morphological characteristics compared to donor plant.  相似文献   
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Journal of Plant Diseases and Protection - Fifteen Pakistan’s indigenous medicinal plant extracts were investigated for various secondary metabolites and their potential against tomato early...  相似文献   
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The analysis of gamma emitters natural radionuclides, i.e., 226Ra, 232Th, and 40K, has been carried out in soil, vegetation, vegetable, and water samples collected from some Northern area of Pakistan, using gamma-ray spectrometry. The ??-ray spectrometry was carried out using high-purity Germanium detector coupled with a computer-based high-resolution multi-channel analyzer. The activity concentrations in soil ranges from 24.7 to 78.5 Bq?kg?1, 21.7 to 75.3 Bq?kg?1, and 298.5 to 570.8 Bq?kg?1 for 226Ra, 232Th, and 40K with the mean value of 42.1, 43.3, 9.5, and 418.3 Bq?kg?1, respectively. In the present analysis, 40K was the major radionuclide present in soil, vegetation, fruit, and vegetable samples. The concentration of 40K in vegetation sample varied from 646.6 to 869.6 Bq?kg?1 on dry weight basis. However, the concentration of 40K in fruit and vegetable samples varied from 34.0 to 123.3 Bq?kg?1 on fresh weight basis. In vegetation samples, along with 40K, 226Ra, and 232Th were also present in small amount. The transfer factors of these radionuclides from soil to vegetation, fruit, and vegetable were also studied. The transfer factors were found in the order: 40K?>?232Th????226Ra. The analysis of water samples showed activity concentrations values for all radionuclides below detection limit. The internal and external hazard indices were measured and found less than the safe limit of unity. The mean value of outdoor and indoor absorbed dose rate in air was found 64.61 and 77.54 nGy?h?1, respectively. The activity concentrations of radionuclides found in all samples during the current investigation were nominal. Therefore, they are not associated with any potential source of health hazard to the general public.  相似文献   
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This paper describes the embryonic development of the common cutworm Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) which is divided into eight embryonic stages, through variations in the egg's contents. Experiments were conducted on the eggs ofS. litura under laboratory conditions. The highest concentration of the protein (min.-max.: 32-! 40 lag/egg) and the lowest of the carbohydrate (min.-max.: 3.0-44.0 lag/egg) were obtained; similarly, the DNA content was smaller (min.-max.: 1.0-38.2 lag/egg) than the RNA (min.-max.: 9.2-360.0 lag/egg) throughout the embryogenesis. Three peaks of ecdysteroid titre were observed which were responsible for appearance of particular events during embryogenesis. The last highest peak of 400_+33.4 lag/egg was appeared at 84 h after oviposition when larva was ready to hatch. Therefore, it is concluded that eight embryonic stages in S. litura were characterized by fluctuation in the egg's contents, which were responsible for gradual-progressive embryonic development. The egg-larval development did not show a normal distribution of embryonic developmental-time.  相似文献   
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Genetic Resources and Crop Evolution - The Saccharum species members are extremely complex allopolyploids. In this study, sixty Saccharum spp. hybrids were analyzed using simple sequence repeat...  相似文献   
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The new asperorlactone (1), along with the known illudalane sesquiterpene echinolactone D (2), two known pyrones, 4-(hydroxymethyl)-5-hydroxy-2H-pyran-2-one (3) and its acetate 4, and 4-hydroxybenzaldehyde (5), were isolated from a culture of Aspergillus oryzae, collected from Red Sea marine sediments. The structure of asperorlactone (1) was elucidated by HR-ESIMS, 1D, and 2D NMR, and a comparison between experimental and DFT calculated electronic circular dichroism (ECD) spectra. This is the first report of illudalane sesquiterpenoids from Aspergillus fungi and, more in general, from ascomycetes. Asperorlactone (1) exhibited antiproliferative activity against human lung, liver, and breast carcinoma cell lines, with IC50 values < 100 µM. All the isolated compounds were also evaluated for their toxicity using the zebrafish embryo model.  相似文献   
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