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41.
Ornamental kale (Brassica oleracea var. Acephala) is usually planted from early autumn until late winter. Since most of the plants used for phytoremediation cannot be grown during this time, kale can be a suitable option for phytoremediation and utilized during autumn and winter in urban landscape, especially in metropolitan areas where high levels of cadmium (Cd) and lead (Pb) pollutions exist. Kale growth in saline soil at different growth stages (germination and vegetative growth stages) was studied in this investigation. A factorial experiment based on completely randomized design (CRD) with four replications was used in this study. Treatments included three levels of sodium chloride (NaCl) (0, 30, and 60 mg/kg), four levels of Cd (0, 4, 8, and 16 mg/kg), and four levels of Pb (0, 1, 5, and 10 mg/kg). Results indicated that increase in Cd and Pb concentrations in the soil decreased fresh and dry weights of the plants. The results of the various growth stages revealed that under salinity stress, kale plants were able to absorb more Pb than Cd and effectively remediate Pb in polluted and saline lands. Cd accumulation in control treatment was 6.2% more than that in the saline treatments, whereas, Pb accumulation in the highest NaCl level, 60 mg/kg salinity treatment was 7.64% more than that of the control condition. Also, proline content of the plants was significantly increased under Cd and Pb stress. From the results of this study, it was concluded that using kale plant is recommended for phytoremediation of saline soils with 10 and 16 mg/kg Pb and Cd contents, respectively.  相似文献   
42.
Free‐floating macrophytes are often common in standing water bodies. Fishponds are suitable medium for Azolla growth; however, it rapidly self‐propagates and doubles its biomass in a few days and could strongly influence nutrient dynamics. The preference of Tilapia zillii (Gervais) to consume the free‐floating plant, Azolla pinnata, was tested in two experiments. In the first experiment, fish with different initial body weights (2–3 g, 7–10 g, 15–20 g, and 50–60 g) were randomly distributed at a rate of 150 ± 5 g/100‐L aquarium and fed fresh A. pinnata for 8 wk. A known weight of fresh plant was given to fish; after 24 h, Azolla remaining in aquaria was collected, dried with tissue paper, and reweighed to determine amount consumed. In the second experiment, fish were fed one of five diets containing different levels of dry Azolla meal as replacements of the control diet (20% crude protein) at levels of 0 (control), 25, 50, 75, or 100% for 13 wk. Growth retardation and weight loss were observed in all fish sizes fed fresh Azolla, and the mortality rates were 53.3–56.7%. The consumption of fresh Azolla decreased over time up to the eighth week; otherwise, Azolla consumption was fish size dependent. Whole‐body contents of crude protein decreased significantly, while total lipids and ash contents increased significantly with increasing fish size. In the second experiment, fish growth was reduced when the level of dry Azolla meal in the diet exceeds 25%. The mortality rate increased significantly with increasing Azolla level in the diet. Carcass composition showed increases in moisture and ash contents and decreases in dry matter, crude protein, and total lipids with the increase of Azolla level in the diets. Amount of diet consumed decreased, while feed conversion ratio increased significantly with the increase in dry Azolla level in the diet. Moreover, protein efficiency ratio, protein productive value, and energy utilization decreased significantly with the increase in dry Azolla level in the diet. It could be concluded that the preference of T. zillii to consume Azolla plants inhabiting water bodies is limited, but it could partially consume the dry Azolla meal at low and moderate levels. The optimum inclusion level of dry Azolla meal should be no more than 25% in T. zillii diet.  相似文献   
43.
Zagros forests are mainly covered byQuercus brantii L. coppices and oak sprout clumps occupy the forest area like patches. We investigated post-fire herbaceous diversity in the first growing season after fire. For this purpose neighboring burned and unburned areas were selected with the same plant species and ecological conditions. The data were collected from areas subjected to different fire severities. Overall 6 treatments were considered with respect to fire severity and the mi-crosites of inside and outside of oak sprout clumps including: unburned inside and outside of sprout clumps (Ni and No), inside of sprout clumps that burned with high fire severity (H), inside of sprout clumps that burned with moderate fire severity (M), outside of sprout clumps that burned with low fire severity (OH and OM). Different herbaceous com-position was observed in the unburned inside and outside of oak sprout clumps. The species diversity and richness were increased in treatments burned with low and moderate fire severity. However, in treatment burned with high fire severity (H), herbaceous cover was reduced, even-ness was increased, and richness and diversity were not significantly changed. We concluded that besides the microsites conditions in forest, fire severity is an inseparable part of the ecological effect of fire on her-baceous composition.  相似文献   
44.
Studies were conducted into effects of Rift Valley fever virus on oestrous and vaginal cytology in non-pregnant ewes. 6 pregnant and 8 non-pregnant local Barki ewes were subcutaneously inoculated with different doses of virus isolated from Sharkia Province. Observed were irregularities in the oestrous cycle (20-28 days inoculation) and anoestrum. The anoestrum smears included large non-cornified epithelial cells with large well stains centrally located nuclei together with a large number of bacteria. Abortion and retention of placenta occurred in pregnant ewes with prolonged puerperal heat up to 70 days. Inoculation of virus was followed by thermal response. Re-isolation of virus in BHK cells was possible from aborted foetuses and placenta.  相似文献   
45.
Chicory (Cichorium spp.) is a valuable vegetable crop worldwide for its edible leaves and for the production of coffee substitutes from roots. Agrobacterium rhizogenes-mediated genetic transformation of two species of chicory (C. intybus and C. endivia) was investigated using Agrobacterium strain K599 harbouring p35SGFPGUS+ plasmid and two types of explants: leave and leaf stalks. This Agrobacterium strain proved to be competent in the transformation with transformation rate about (23.1%) in leaf explants of C. intybus. However, the transformation rate with C. endivia was much lower (3.6%). Moreover, the hairy roots appeared from different infection sites of the leaf explants. Several hairy roots of the two species were acquired, out of them 11 clones (C. intybus) and two clones (C. endivia) were selected due to their fast-growing character. Growth of hairy roots was determined on the basis of total root biomass accumulation. It was found that the liquid MS-basal medium seems to be the most suitable for biomass production. PCR analysis revealed foreign DNA integration in the selected transgenic hairy root clones. Notable, the transgenic hairy roots exhibited substantially higher growth rates and accumulated higher amount of inulin than non transgenic roots (WT). Also, the total phenolic compounds were determined.  相似文献   
46.
Preservation of elite key lime (Citrus aurantifolia) genotypes using efficient micropropagation and regeneration protocols is very important for new breeding programmes. The objective of the present study was to develop an efficient protocol for micropropagation and maintenance of elite genotypes of key lime based on slow growth and starvation strategy. To do this, regenerated shoots were starved, and the growth was compromised via avoiding subcultures for 4, 8, 12 and 24 months. The numbers of responsive explants and adventitious shoots per each explant were evaluated in the presence of benzylaminopurine (BAP). The results showed that the 12- and 24-month starved explants treated with 1 mg/l BAP were able to produce four times more shoots than the control. In addition, the influences of horizontal or vertical layering explants over medium were evaluated. The results indicated that all horizontally layered explants significantly produced 25% adventitious shoots more than vertical explants, most likely owing to more contact with the surface medium. Finally, it could be concluded that application of slow growth, starvation strategy and also horizontally layering of the explants could efficiently enhance micropropagation and maintenance of threatened elite key lime genotypes with a low cost.  相似文献   
47.
In 2012, a greenhouse experiment was conducted to investigate the effects of field soil (C0), residual composted municipal waste (CMW), and residual composted sheep manure (SM) on the growth of triticale in pots previously growing oilseed rape in 2011. To each soil group, one of three levels of urea nitrogen (N) fertilizer was added. Results demonstrated that triticale grown in pots previously containing oilseed rape plants containing SM or CMW with 150 kg urea N ha?1 had the highest N content. Plants grown in SM with 150 kg N ha?1 had the greatest seed yield, but yield was not significantly different from plants grown in CMW receiving 150 kg N ha?1. Triticale plants enriched by either SM or CMW had a higher amount of N, copper, zinc, and manganese compared to the field soil control.  相似文献   
48.
Veterinary Research Communications - Industrial chemical solutions are widely used as a method to disinfection of aquaculture water and environments. The aim of the present study was to evaluate...  相似文献   
49.
Ralstonia solanacearum and Meloidogyne incognita are two soilborne pathogens that cause serious damage and great losses in the production of tomato. For this purpose, a bacterial isolate, Bacillus thuringiensis CR-371, and an actinomyces isolate, Streptomyces avermectinius NBRC14893, were examined for their ability to protect tomato from root-knot nematode and bacterial wilt diseases under glasshouse conditions. Treatment of tomato roots with B. thuringiensis CR-371 and S. avermectinius NBRC14893 followed by challenge inoculation with R. solanacearum and M. incognita significantly decreased disease severity of bacterial wilt alone, root-knot nematode alone, or mixed infection by both pathogens compared to the control. Furthermore, pretreatment of tomato roots with B. thuringiensis CR-371 and S. avermectinius NBRC14893 significantly reduced bacterial proliferation of R. solanacearum both in pathogen alone inoculated plants and in plants co-inoculated with R. solanacearum and M. incognita. In conclusion, our results suggest that the treatment of tomato roots with B. thuringiensis CR-371 and S. avermectinius NBRC14893 simultaneously suppresses bacterial wilt and root-knot nematode diseases. Therefore, B. thuringiensis CR-371 and S. avermectinius NBRC14893 could provide new options for integrated pest management strategies against plant diseases, especially against bacterial-nematode disease complexes that cause synergistic yield losses.  相似文献   
50.
BACKGROUND: Anopheles culicifacies is a main malaria vector in southeastern part of Iran, bordring Afghanistan and Pakistan. So far, resistance to DDT, dieldrin, malathion and partial tolerance to pyrethroids has been reported in An. stephensi, but nothing confirmed on resistance status of An. culicifacies in Iran. METHODS: In current study, along with WHO routine susceptibility test with DDT (4%), dieldrin (0.4%), malathion (5%), permethrin (0.25%), lambadacyhalothrin (0.1%), and deltamethrin 0.025, we cloned and sequenced segment VI of domain II (SII6) in voltage-gated sodium channel (vgsc) gene of An. culicifacies specimens collected in Sistan and Baluchistan province (Iran). RESULTS: A 221-bp amplified fragment showed 91% and 93% similarity with exon I and exon II of An. gambiae. The size of intron II in An. culicifacies is 62 bp, while in An. gambiae is 57 bp. The major difference within An. culicifacies specimens and also with An. gambiae is in position 29 of exon I, which led to substitution of Leu to His amino acid. CONCLUSION: This data will act as first report on partial sequence of vgsc gene and its polymorphism in An. culicifacies. A Leu to His amino acid substitution detected upstream the formerly known knockdown resistance (kdr) mutation site could be an indication for other possible mutations related to insecticide resistance. However, the result of WHO susceptibility test carried out in Baluchistan of Iran revealed a level of tolerance to DDT and dieldrin, but almost complete susceptibility to pyrethroids in An. culicifacies. We postulate that the molecular diagnostic tool developed for detection and identification of kdr-related mutations in An. culicifacies, could be useful in monitoring insecticide resistance in Iran and neighbouring countries such as Pakistan and Afghanistan. A phylogenetic tree also constructed based on the sequence of exon I and II, which readily separated An. culicifacies populations from An. stephensi, An. fluviatilis and An. gambiae.  相似文献   
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