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41.
水稻草矮病毒NS6基因在大肠杆菌中的表达及植物表达载体的构建 总被引:2,自引:0,他引:2
Large amount of disease-specific protein(SP) accumulated in the rice plant cells infected by rice grassy stunt virus(RGSV). It was deduced that the protein was encoded by NS6 gene on genomic vRNA6 and thus referred to as NS6 protein.But its function is unknown. In an effort to prove the above deduction and to elucidate the function of NS6 protein of RGSV, we constructed a bacterial expression plasmid pGTNS6 producing a fusion protein of glutathione S-transferase (GST) and NS6 protein, and a plant expression vector pCBTNSv6 containing NS6 gene. A recombinant plasmid pTNSv 6 containing the coding region of NS6 gene and the non-coding region at its 5' terminus, cloned by RT-PCR from purified RNAs of Shaxian isolate of RGSV, was used as the start point. Western blot analysis showed that the fusion protein reacted strongly with antisera raised against RGSV-SP, which served as evidence of the deduction.EHA105 of Agrobacterium tumefasciens containing pCBTNSv6 has been obtained and the transformation of rice is underway. 相似文献
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Over nearly three decades, Suzanne Prober has played a pivotal role in shifting research in Australian agricultural landscapes to include a focus on native woodlands, and to examine ways woodland conservation can co‐exist with production, contributing to new models for conservation within multi‐use landscapes. 相似文献
44.
草基—鱼塘生态系统的能量转化与养分循环研究 总被引:7,自引:2,他引:5
应用模拟试验的方法,研究了“草基-鱼塘”系统中的能量转化与养分循环.结果 表明,该系统中饲草对太阳能的利用率为 0. 83%,鱼对饲料能的转化率为 7. 3%.与以粮 食作为鱼饲料比较,单位面积草地的产鱼当量是粮食作物的1.6倍.鱼对饲料N、P、K的 转化率分别为16.8%、32.3%和2.0%.塘泥沉积的N、P分别占饲料的23.4%和56.1%; 猪对饲料 N、 P、 K的转化率分别为 20. 5%、 33. 7%和 4. 6%,猪粪尿回收饲料 N为 36. 4%、 P为 63. 8%、 K为 39. 4%.猪-草-鱼结合的基塘系统其能量和养分转化效率均高于单一的 养鱼系统. 相似文献
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Comparison of bacterioplankton communities in three mariculture ponds farming different commercial animals in subtropical Chinese coast 总被引:1,自引:0,他引:1
In order to explore the responses of the bacterioplankton community to different types of aquaculture environments, three
mariculture ponds comprised of groupers (Epinephelus diacanthus, ED), prawns (Penaeus vannamei, PV), and abalone (Haliotis
diversicolor supertexta, HDS) in southeast, coastal China were investigated. The free-living bacterial diversity was analyzed through
the construction of 16S rDNA clone library. A total of 203 16S rDNA sequences from three clone libraries were classified into
118 operational taxonomic units (OTUs), of which 51, 31, and 42 OTUs were distributed in the ED, PV, and HDS pond, respectively,
with Bacteroidetes (30.6%), Actinobacteria (55.2%), and Cyanobacteria (32.8%) as the dominant division in the respective ponds. Meanwhile, each pond occupied some unique OTUs that were affiliated
with uncommon (sub-)phyla, such as candidate OP11 division, Acidobacteria, Deltaproteobacteria, Planctomycetes, and Verrucomicrobia. Bacterial diversity in the ED pond was the richest, followed by the HDS and the PV pond. OTUs of 61.9% and 94.9% have less
than 90% and 97% similarity to their nearest neighbors in public databases, respectively. All OTUs were grouped into 67 clusters,
covering 11 (sub-)phyla. The OTUs only from single pond distributed in 53 clusters (79.1%), the OTUs shared by two ponds were
affiliated with 14 clusters (20.9%), and none of clusters was formed by the OTUs which commonly originated from the three
pond libraries, suggesting that the composition of bacterial populations in these ponds were significantly different. These
results indicate that the aquatic environment created by different mariculture animals may foster very special and complex
bacterial communities.
Handling editor: David Philip Hamilton 相似文献
48.
Water levels were recorded weekly from six natural vernal pools and 10 created vernal pools at two forested wetland complexes
in central Ohio. Vernal pool median water depth and duration of inundation were significantly greater at the created vernal
pools than at the natural vernal pools (α = 0.05, P < 0.05). The average period of inundation for created pools was 309 ± 32 days, compared with 250 ± 16 days for natural pools.
The created pools produced a range of inundation times, from 163 to 365 days in length, with three pools permanently inundated. 相似文献
49.
Biological kinetic (bio-kinetic) study of the anaerobic stabilization pond treatment of palm oil mill effluent (POME) was carried out in a laboratory anaerobic bench scale reactor (ABSR). The reactor was operated at different feed flow-rates of 0.63, 0.76, 0.95, 1.27, 1.9 and 3.8 l of raw POME for a day. Chemical oxygen demand (COD) as influent substrates was selected for bio-kinetic study. The investigation showed that the growth yield (YG), specific biomass decay (b), maximum specific biomass growth rate (μmax), saturation constant (Ks) and critical retention time (Θc) were in the range of 0.990 g VSS/g CODremoved day, 0.024 day−1, 0.524 day−1, 203.433 g COD l−1 and 1.908 day, respectively. 相似文献
50.