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91.
Field experiments during two successive rainy seasons were conducted in southern Vietnam to evaluate the effects of a commercial inoculant biofertilizer (‘BioGro’) and fused magnesium phosphate (FMP) fertilizer on yield and nitrogen (N) and phosphorus (P) nutrition of rice. Inoculation with BioGro containing a pseudomonad, two bacilli and a soil yeast significantly increased grain yield in the second season and straw yield in both seasons by 3–5%. The FMP fertilizer significantly increased grain yield from 1.72–2.33 t ha?1 to 2.99–3.58 t ha?1 along with total N and P accumulation at all rates in both cropping seasons. In the first season the difference in grain yield between BioGro treated and untreated plots was marginal but in the second season BioGro out-yielded the control at all the rates of added P. Overall, BioGro application did not compensate for low P fertilizer application to the same extent previously demonstrated for low N fertilizer applications.  相似文献   
92.
Cyadox (CYX) is a synthetic antibacterial agent of quinoxaline with much lower toxic effects. A safety criterion of CYX for clinical use was established by studying the pharmacokinetics and metabolism of CYX after oral (PO), intramuscular (IM), and intravenous (IV) administration. CYX was administered in six domesticated cats (three males and three females) by PO (40 mg/kg.b.w.), IM (10 mg/kg.b.w.), and IV (10 mg/kg.b.w.) routes in a crossover pattern. Highly sensitive liquid chromatography with ultraviolet detection (HPLC-UV) method was developed for detection of CYX and its metabolites present in plasma, urine, and feces. The bioavailability of CYX after PO and IM routes was 4.37% and 84.4%. The area under curves (AUC), mean resident time (MRT), and clearance (CL) of CYX and its metabolites revealed that CYX quickly metabolized into its metabolites. The total recovery of CYX and its main metabolites was >60% after each route. PO delivery suggesting first pass effect in cats that might make this route suitable for intestinal infection and IM injection could be better choice for systemic infections. Less ability of glucuronidation did not show any impact on CYX metabolism. The findings of present study provide detailed information for evaluation of CYX.  相似文献   
93.
Tropical Animal Health and Production - Non-additive genetic effects are important to increase the accuracy of estimating genetic parameters for growth traits. The aim of this study was to estimate...  相似文献   
94.
Fig (Ficus carica) is an exotic deciduous plant that is grown worldwide. Fungal diseases pose a major threat to fig plants, affecting their fruit quality and production. This study was conducted to characterize the fungal isolates associated with leaf blight, stem rot and fruit rot of F. carica in Malaysia through morphological analysis, DNA sequencing, multigene phylogenetic analysis and pathogenicity tests. From September 2018 to March 2019, 30 blighted leaves and 30 rotted stems and fruits of F. carica were collected from several nurseries in Malaysia. Thirty fungal isolates that belonged to Lasiodiplodia theobromae (27 isolates) and L. brasiliensis (three isolates) were identified based on morphological characteristics, comparison of DNA sequences and phylogenetic analysis of the internal transcribed spacer (ITS), elongation translation factor 1-α (tef1-α), β-tubulin (tub2) and DNA-directed RNA polymerase II subunit (rpb2). Among the 27 isolates of L. theobromae, nine isolates were obtained from leaves, eight isolates from stems and 10 isolates from fruits, whereas the three isolates of L. brasiliensis were obtained from stems (two isolates) and a leaf (one isolate). The results of pathogenicity tests revealed that L. theobromae and L. brasiliensis isolates were responsible for leaf blight and stem rot of F. carica, whereas fruit rot was caused by L. theobromae isolates. The present study highlighted two different species, L. theobromae and L. brasiliensis, as the causal agents of leaf blight and stem rot of F. carica. Additionally, L. theobromae caused fruit rot of F. carica in Malaysia.  相似文献   
95.
Seagrasses, a functional group of marine flowering plants rooted in the world’s coastal oceans, support marine food webs and provide essential habitat for many coastal species, playing a critical role in the equilibrium of coastal ecosystems and human livelihoods. For the first time, the probability of extinction is determined for the world’s seagrass species under the Categories and Criteria of the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species. Several studies have indicated that seagrass habitat is declining worldwide. Our focus is to determine the risk of extinction for individual seagrass species, a 4-year process involving seagrass experts internationally, compilation of data on species’ status, populations, and distribution, and review of the biology and ecology of each of the world’s seagrass species. Ten seagrass species are at elevated risk of extinction (14% of all seagrass species), with three species qualifying as Endangered. Seagrass species loss and degradation of seagrass biodiversity will have serious repercussions for marine biodiversity and the human populations that depend upon the resources and ecosystem services that seagrasses provide.  相似文献   
96.
97.
Abstract

Phosphorus status of Bangladesh paddy soils covering the major paddy soil types was assessed in terms of parent materials and physiography. Total P concentration ranged from 172 to 604 mg kg?1 in the topsoil and from 126 to 688 mg kg?1 in the subsoil, and varied with the physiography to which the soils belonged. In most soils, the available P concentration was much higher for the topsoil than for the subsoil. The inorganic P concentration was higher than the organic P concentration, except for one soil series from the Old Himalayan Piedmont Plain, and was significantly and positively correlated with the total P concentration. Among the inorganic forms, only the concentration of Al-bound P showed a significant correlation with that of available P based on the Bray P-2 method in both topsoil and subsoil. In general, the P status was critically low in paddy soils of the terrace area. Normal growth of paddy rice in this area is expected to be difficult without application of P fertilizer.  相似文献   
98.
99.
Field experiments were conducted during successive rainy seasons in 2006 in the Chau Thanh district of southern Vietnam to evaluate the effects of an inoculant plant growth promoter product called “BioGro” and N fertiliser rates on yield and N and P nutrition of rice. The results indicated that inoculation with BioGro, containing a pseudomonad, two bacilli and a soil yeast, significantly increased grain and straw yields and total N uptake in both seasons, as well as grain quality in terms of percentage N. Nitrogen fertilisation increased grain and straw yields as well as total N and P uptakes significantly in both cropping seasons. The estimated grain yield response to added N was quadratic in nature with and without added BioGro. In the first crop, BioGro out-yielded the control up to 90 kg urea N ha?1 whilst in the second season the beneficial effect of BioGro was observed up to 120 kg urea N ha?1, indicating either an interaction of the inoculant with higher yielding seasonal conditions or a cumulative effect of BioGro application. In the first season, the estimated N rate for maximum grain yield was 103 kg N ha?1 with BioGro while it was 143 kg N ha?1 without BioGro. The maximum estimated grain yields were 3.21 and 3.18 t ha?1 with and without BioGro, respectively. This information indicates that BioGro was able to save 40 kg N ha?1 with an additional rice yield of 30 kg ha?1 in the season. In the second rainy season, the estimated N rates for maximum grain yields were 94 and 97 kg N ha?1 with and without BioGro, respectively. The estimated maximum grain yields were 3.49 and 3.25 t ha?1 with and without BioGro, respectively. The two seasons’ combined results indicate that application of BioGro improved the efficiency of N use by rice significantly, saving 43 kg N ha?1 with an additional rice yield of 270 kg ha?1 in two consecutive seasons at the experimental site. The extra efficiency was shown by the fact that the same yield of rice was obtained with about 40 and 60 kg less fertiliser-N that the maximum yields with urea alone in the two successive harvests on the same plots.  相似文献   
100.
A batch experiment was conducted to study the effect of pH on the sorption of copper (Cu), cadmium (Cd), zinc (Zn), and nickel (Ni) by cement kiln dust (CKD). The experiment was carried out by adding 25 mL of solutions containing concentrations of 200, 400, 600, 800, and 1000 mg/L of each of these heavy metal cations to 1.00 g of CKD. The pH of these suspensions was adjusted to 2, 5, and 7 as well as non-adjusted. The sorbed amount (Cs) and the sorption percentage of Cu, Cd, Zn, and Ni by CKD increased with increasing the suspension pH. The adsorption data of Cu, Cd, Zn, and Ni were generally well correlated with Langmuir model when the suspension pH was adjusted to 5, 7, non-adjusted and 7, respectively. However, they could be well described by Freundlich model when the suspension pH was adjusted to 5, 2, non-adjusted and 5, respectively.  相似文献   
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