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21.
Reports on varietal diversity of upland rice in relation to relatively low aluminium (Al) levels are limited. Therefore, effects were examined of 35, 70, and 140 μM Al on plant growth and uptake of macro‐ and micro‐nutrients (K, P, Ca, Mg, Fe, Zn, Cu, and Mn) and their distribution in three upland rice (Oryza saliva L.) cultivars (BG35, DA14, and IR45) with different Al sensitivity. After an initial growth period of 5 days without Al, the plants were grown for 21 days in nutrient solutions containing Al at pH 4.1. Cultivar BG35 showed the highest and IR45 the lowest tolerance to Al when fresh weights of shoots or roots were considered. Except for IR45 at 140 μM Al, total dry weight was unaffected by Al, and the cultivars could not be clearly distinguished with respect to Al tolerance. Net Al uptake rate was higher in Al tolerant BG35 than in DA14 or IR45. Conversely, in IR45 the absorbed Al was rapidly transported to the shoots and accumulated there. In BG35, net P and Ca uptake rates in Al‐treated plants were high enough to maintain the P and Ca status of the shoots at all Al levels. Irrespective of Al sensitivity, there was a general depression of internal Mg concentration in Al‐reated plants. The Fe, Zn, Cu, and Mn concentrations of the plants were not negatively affected by Al in any of the cultivars.  相似文献   
22.
High pressure processing (HPP) can shuck (open) shellfish, saving labor while conferring food safety and yield benefits. Mostly male New Zealand Greenshell? mussels (Perna canaliculus) were HPP-shucked (3 min at 500 MPa, 30°C) and assessed during 6-days’ ice storage (0°C) for cooked yield, color, and texture compared with heat processed (1 min at 70°C) and untreated samples. HPP-treated mussels had improved yields but lost more weight during ice storage. Male mussels from all treatments became darker with ice storage. HPP-treated mussels had firmer adductor muscles, while their guts required higher maximum force but less energy to puncture them.  相似文献   
23.
Cotton (Gossypium hirsutum L.) is a well-known and economically most beneficial crop worldwide while nickel (Ni) toxicity is a widespread problem in crops grown on Ni-contaminated soils. We investigated the response of silicon (Si) in cotton under Ni stress with respect to growth, biomass, gas exchange attributes, enzymatic activities, and Ni uptake and accumulation. For this, plants were grown in hydroponics for 12 weeks with three levels of Ni (0, 50, and 100 µM) in the presence or absence of 1 mM Si. Results showed that Ni significantly reduced the plant growth, biomass, gas exchange attributes, and pigment contents while Si application mitigated these adverse effects under Ni stress. Nickel stress significantly decreased antioxidant enzymes’ activities while increased malondialdehyde (MDA), hydrogen peroxide (H2O2), and electrolyte leakage (EC) in leaves and roots. The application of Si enhanced the activities of antioxidant enzymes and reduced MDA, H2O2, and EC in plants. Nickel application significantly increased Ni concentration and accumulation in leaf, stem, and roots while Si application significantly decreased Ni in these plant parts. The present study indicates that Si could improve cotton growth under Ni stress by lowering Ni uptake and reactive oxygen species (ROS) and by increasing antioxidant enzymes activities.  相似文献   
24.
Allelopathic effects of Eucalyptus camaldulensis Dehnh. were confirmed in Petri dish and pot experiments in our previous studies. However, the degree to which such effects under controlled experiments exist in more complex ecological settings remains to be tested. Thus, the present study was carried out by incorporating different proportions of ground litter of E. camaldulensis in soil. The growth of three agricultural crops: falen(Vigna unguiculata(L.) Walp.), chickpea(Cicer arietinum L.), and arhor(Cajanus cajan(L.) Millsp.), and two tree species, kala koroi(Albizia procera(Roxb.) Benth.) and ipil ipil(Leucaena leucocephala(Lam.) de Wit) were tested. There were inhibitory effects of leaf litter on germination, shoot and root growth, leaf number, and collar diameter as well as a reduction of nodulation by legume crops(25–80%reduction). The extent of the effects was dependent on the proportion of leaf litter, the species and the type of traits. In contrast to shoot growth, the effect on root growth was more severe. No effect on germination was found with the agriculture crops while the two tree species showed reduced germination. The effect was greater in the presence of higher proportions of leaf litter mixed in soil while in some cases lower proportions stimulated growth. Not all species were suppressed; A. procera, C. cajan, V. unguiculata showed compatible growth while C. arietinum and L.leucocephala were found incompatible. This study provides evidence that E. camaldulensis has allelopathic potential under field conditions and a careful selection of associated crops in agroforestry systems is highly recommended.  相似文献   
25.
Evaluation of the antioxidant and antiteratogenic role of ginger Zingiber officinale polyphenols against the toxicity induced by fenitrothion and/or lead in female albino rats were investigated. Adult virgin females were divided into 8 groups and were orally treated as follow: control (C), 1% w/w of ginger (G), 120 μg/animal lead as lead acetate (L), 10 mg/kg of fenitrothion (F), lead (120 μg/animal) fenitrothion (10 mg/kg) (LF), ginger (1%w/w) + fenitrothion (10 mg/kg) (GF), ginger (1%w/w) + lead (120 μg/animal) (GL), ginger (1%w/w) + lead (120 μg/animal) + fenitrothion (10 mg/kg) (GLF). Treatments were expanded for 28 days before pregnancy and during gestation period from zero to 6th day. Blood samples were taken at the day 20th of gestation and animals were sacrificed to investigate the effect of tested substances on dams and development of their fetuses. Inhibition in AchE in (F) and (LF) groups and elevation in plasma AchE in (L) groups were observed. Elevation in oxidative stress biomarker malondialdehyde (MDA) was recorded in all intoxicated groups concomitants with reduction in total reduced glutathione (GSH) and reduction in the activity of glutathione S-transferase (GST). Elevation in liver function biomarkers alanin amintransferase (ALT) and aspartate aminotransferase (AST) and reduction in plasma total protein and albumin were recorded in (F), (L) and (LF). Supplementation with ginger in diet attenuates the alteration in MDA, GSH, GST, ALT and AST, however, it failed to counteract the effect of F, L and LF on AchE, total protein and albumin. Significant alterations in maternal toxicity were recorded in (GF, GL, LF and GLF) compared with control group. Also, parameters of embryotoxicity and fetotoxicity indicated significant decrease in litter number that observed in F and L and the number of dead fetus/dam and litters number increased in L group. Supplementation with ginger decreased each of the number of died fetus, growth retardation and fetal length, while, it increased fetal weight. As regards to, teratological aspects, the percentage of skeletal malformations and visceral anomalies were observed in all feti obtained from treated groups with different percentages. Supplementation with ginger slightly attenuates the developmental toxicity of fenitrothion and/or lead.  相似文献   
26.
This study concerns the transformation of maritime pine (Pinus pinaster) sawdust waste into potentially novel products through isolation of volatile compounds in the form of valuable oil. Different techniques, namely, turbohydrodistillation (THD), solvent-free microwave extraction (SFME), microwave hydrodiffusion and gravity (MHG), and ultrasound-assisted extraction (UAE) were tested. These different processes were compared to conventional hydrodistillation (HD) and allowed to extract almost similar yields of isolated oils. THD which consists in a permanent agitation during extraction and UAE improve the kinetics of extraction, but MHG and SFME required the shortest extraction times, 60 min to reach a maximal yield of 0.272 and 0.266% (w/w), respectively. The compositions of isolated oils are almost similar with a high proportion of oxygenated compounds for MHG and SFME, respectively, 56.9% and 54.5% compared with 37.7%, 44.1% and 34.1%, respectively, for THD, UAE, and for the conventional HD method.  相似文献   
27.
Abstract

Zinc (Zn) as a microelement plays a salient role in the vital processes of plants such as metabolism and nutrition. This experimental study was conducted in the research field of Agriculture Faculty, Zanjan University using two genotypes of canola as main factor (Okapi and Tassilo) and zinc fertilizer application method in 7 levels including control, foliar spraying (2, 3.5, and 5?g/L) at the beginning of flowering and soil application (25, 50, and 75?kg/ha) were considered as sub-plot factor. The results showed that the application of zinc significantly increased the chlorophyll content as compared to control treatment. The highest chlorophyll content was observed in foliar spraying of 3.5 and 5?g/L zinc in Okapi cultivar. While, the highest value of RWC content resulted only with spraying 5?g/L of zinc. The result showed that zinc foliar of 5?g/L obtained the highest oil and seed yields and seed yield components. In addition, the highest qualitative seed traits (oil and protein content and zinc content in seed and plant) resulted with spraying 5?g/L of zinc. Also, Okapi cultivar had more quantitative and qualitative yields than Tassilo cultivar. The foliar spray of 5?g/L Zn can be recommended to increase the quantity and quality seed yield of canola.  相似文献   
28.
Thin films often present domain structures whose detailed evolution is a subject of debate. We analyze the evolution of copper films, which contain both rotational and stacking domains, on ruthenium. Real-time observation by low-energy electron microscopy shows that the stacking domains evolve in a seemingly complex way. Not only do the stacking boundaries move in preferred directions, but their motion is extremely uneven and they become stuck when they reach rotational boundaries. We show that this behavior occurs because the stacking-boundary motion is impeded by threading dislocations. This study underscores how the coarse-scale evolution of thin films can be controlled by defects.  相似文献   
29.
Two upland rice (Oryza sativa L.) cultivars with high (IR45) and low (BG35) aluminium (Al) sensitivity were selected to investigate the influence of Al on growth and uptake and distribution of macronutrients [potassium (K), phosphorus (P), calcium (Ca), and magnesium (Mg)] when the plants were grown at various levels of nutrient supply. The plants were grown for 21 days with or without 140 μM Al at pH 4.1. Nutrients were supplied with 2.5, 5.0, 10, or 15% relative increase/day relative nutrient addition rate (RNR), according to a nutrient supply program. In this range of nutrient supply rates, the degree of Al sensitivity in the two rice cultivars was not markedly affected, except for root growth in BG35 that was more inhibited at low RNRs than at high RNRs. Regardless of nutrient supply rate, Al was mainly confined to the roots in both cultivars. However, the concentrations of Al in the shoots was consistently lower in BG35 than in IR45. Different Al sensitivity in BG35 and IR45 was associated with different influence on uptake and distribution of P and Ca. Uptake of Mg was drastically inhibited by Al at all nutrient supply levels in both cultivars. Uptake and distribution of K were not negatively affected by Al.  相似文献   
30.
  1. The mangrove horseshoe crab, Carcinoscorpius rotundicauda, has divergent populations between the east and west coasts of Peninsular Malaysia, with the southern coast acting as a land barrier. The actual position of such a genetic break along Peninsular Malaysia as well as the connectivity status of the southernmost C. rotundicauda populations with east and west coast populations remain unexplored, however.
  2. The aim was to investigate the genetic diversity and structure of C. rotundicauda populations from the west (Kuala Sepetang in State Perak), east (Balok in State Pahang), and southern (Pendas in State Johor) coasts of Peninsular Malaysia. Haemolymph samples from adult C. rotundicauda specimens (n = 152) and eggs from their freshly deposited nests (n = 190) were collected monthly (from January 2016 to January 2017) for the sequencing of mitochondrial cytochrome c oxidase subunit I (COI).
  3. Gene isolates of C. rotundicauda from the present study were compared with National Center for Biotechnology Information (NCBI) GenBank sequences to cover most of the range of the species in Asia. A neighbour-joining tree strongly supported two clades, separating the west-coast populations from the south- and east-coast populations, with further substructure patterns.
  4. Both haplotype network and barrier analyses revealed a genetic break within the Strait of Malacca instead of the southern tip of Peninsular Malaysia. The southernmost samples from the Strait of Johor formed a haplotypic diverse gene pool that appeared only as a subclade of the eastern populations. In a detailed haplotype network of 347 individuals, individuals with similar COI sequences indicate connectivity between C. rotundicauda on the east and C. rotundicauda on south and south west of Peninsular Malaysia.
  5. Overall, the genetic break between C. rotundicauda populations is better explained by the convergent ocean currents and available mangrove habitats on the west coast (i.e. Strait of Malacca), rather than the point of the Malay Peninsula acting as a land barrier alone.
  相似文献   
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