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61.
通过对绿色植物生长调节剂GGR8号在寒富苹果栽培上的应用进行的试验研究,结果表明:GGR8能够提高寒富苹果的品质,20、40、60 mg·kg-1等3种施用浓度在新梢生长量、含糖量、硬度方面均比对照有所提高,尤以60 mg·kg-1的施用浓度应用效果最好,其新梢生长量达到了36.7 cm,比对照增加9.3 cm;单果质量达到了240 g,比对照增加了95 g;含糖量达到了15%,比对照提高3个百分点;硬度达到了9.5 kg·cm-2,比对照增加了1.1 kg·cm-2。  相似文献   
62.
1999年6月9月,使用池塘3口(面积1.21hm^2)培育草鱼种。经87d,总产10571kg,其中草鱼种6249kg,出塘率92.5%,饵料系数1.57;鲢、鳙鱼种4322kg,出塘率71.3%。总产值7.35万元,利润4.15万元。同时对草鱼夏花至秋片不同生长阶段蛋白质需求量,以及颗粒饲料粒径与鱼口裂大小关系等进行了试验。  相似文献   
63.
用8%胺鲜酯水剂在大白菜上进行田间药效试验,试验表明,在大白菜的大田返青期、生长期喷施,能有效地促进大白菜的生长,提高大白菜的产量。对大白菜中的维生素C和可溶性固形物含量等品质指标未发现有不良影响,且对品质有所提升。  相似文献   
64.
  1. This study evaluated the circle hook use as a tool for shark management in the pelagic longline fishery in the Gulf of Gabès.
  2. The usual J‐hook No. 2 with 10° offset, which has been traditionally used by the fishery, was compared to the 18/0 non‐offset circle hook in an alternating fashion along the main line. In total, 22 experimental longline sets were deployed through the shark fishing seasons of 2016 and 2017 to examine the effects of hook types on the catch composition, the catch rates, the hooking location, and the status at haulback.
  3. The catch composition differed significantly among hook types. Moreover, an overall increase in catch rates for the main species, the sandbar shark Carcharhinus plumbeus, and the shortfin mako shark Isurus oxyrinchus, was observed when using circle hooks.
  4. There was no size‐selective effect of circle hooks for the common species. The circle hooks were not effective at reducing at‐haulback mortality of sandbar shark. Conversely, shortfin mako and smooth‐hound shark Mustelus mustelus showed significantly lower relative mortality at haulback with circle hooks than with J‐hooks. Furthermore, circle hooks were more frequently hooked externally than the J‐hooks for the three shark species.
  5. Results demonstrated that the use of 18/0 non‐offset circle hooks in the pelagic shark longline fishery can reduce mortality at haulback for some species without any benefit for the dominant species, the sandbar shark.
  6. Overall, it is difficult to promote the adoption of the use of circle hooks as a management measure in this specialized fishery. Management measures focusing on fishing effort controls, fishing closures in critical habitats, and size limits could have significant benefits for the conservation of shark species and may help to improve the sustainability of the shark fishery in the Gulf of Gabès.
  相似文献   
65.
Rabies is an enzootic viral disease widespread throughout the world. Although it is a vaccine-preventable disease, the annual number of human deaths caused by rabies is estimated to be 32,000 in Asia. Phylogenetic analysis based on sequence data of the partial N gene of rabies viruses in Asia has shown that the viruses are divided into five genogroups, distributed in Middle East, South Asia, South East Asia, Malay, and Arctic regions. The genetic relationships among these rabies viruses agree basically with the results of previous studies. Meanwhile, new types of vaccines are being developed by applying gene manipulation techniques to rabies virus in order to overcome the disadvantages of current vaccines. This article reviews the molecular epidemiology of rabies in Asia and progress made in the development of new-generation rabies vaccines with the goal of elimination or control of rabies in Asia.  相似文献   
66.
Chinese native chicken breeds provide useful resources for the study of genetic diversity. In this study, the alleles of CD8 alpha and CD3d cDNA from Chinese native and introduced western breeds of chicken were analyzed at the sequence level. Six alleles were found, due to 13 amino acid replacements in the extracellular domain of the CD8 alpha sequence. There were four alleles detected in the Chinese strains, and alleles 5 and 6 were identified for the first time. Allele 6 was shared by Langshan, Beijing Fatty and Recessive White Feather chickens. Allele 2, found in the Bigbone strain, was the same as that found in the Leghorn strain H.B15.H7, and allele 3 in the Xianju breed was also the same as in the Leghorn strain H.B15.H12. Two Leghorn lines (RPL line 7 and AY519197) and the Camellia possessed an allele (alleles 1, 4 and 5), respectively, that was not found in the other lines. Nine out of 13 amino acid replacements were situated in the putative major histocompatibility complex (MHC) class I binding CDR1 (positions 30, 33 and 34), CDR2 (positions 58, 62, 63 and 65) and CDR3 (positions 90 and 106). Except for the Xianju breed, the CD8 alpha cDNA of Chinese native chicken breeds shared high homology. Two alleles were found in CD3d. Three additional nucleotides were found at positions 64, 65 and 66 in the newly discovered allele 2. This led to a difference of four amino acids (at residues 22, 23, 24 and 25) in the extracellular domain of CD3d cDNA from the Gushi, Recessive White Feather and ISA chickens compared with these of the White Leghorn and T11.15 (NM_205512). Five hybridoma clones (1C9, 1H5, 4B11, 6G5 and 13C5) against chicken CD8 alpha were generated by DNA immunization. Two monoclonal antibodies (mAbs), 6G5 and 4B11, showed reactivity to the splenocytes from five Chinese native chicken breeds, the Recessive White Feather chicken and the Leghorn (AY519197), while mAbs 1C9, 1H5 and 13C5 showed no reaction with these breeds.  相似文献   
67.
李小丽  张婷 《长江蔬菜》2015,(20):80-81
针对中甘8号甘蓝种植过程中基肥与追肥搭配不合理的问题,开展甘蓝基肥施用的 N、P、K 最佳配比、最佳追肥水平的研究。研究结果表明,以 N∶P2O5∶K2O 为13∶5∶7的洋洋复合肥加农家肥作基肥,甘蓝产量高、商品性好;每667 m2施用25 kg 的尿素作追肥,甘蓝综合性状较好。  相似文献   
68.
Wheat microsatellite XGWM261, due to its closely linked to the dwarfing gene Rht8, has been adopted as the diagnostic molecular marker of Rht8. Screening 408 Chinese and 98 exotic varieties showed 13 allele variants in locus of XGWM261, with 6 alleles only to be found in Chinese varieties and 2 only in exotic varieties, respectively. Sequencing results of the 13 alleles revealed their absolute fragment sizes with 216, 212, 210, 206, 204, 202, 200, 196, 194, 192, 190, 174, and 164 bp, respectively. Allelic distribution analysis showed that the 204, 192, 174, and 164 bp alleles were prevailing in Chinese varieties, and the diagnostic 192 bp allele to Rht8 had a very high percentage in the Yellow and Huai River Valleys Facultative Wheat Zone than in the Northern Winter Wheat Zone in China. The GT → AC substitution at position 35 was found in 216, 200, and 174 bp alleles. Moreover, the AG insertion immediately at the end of CT-repeat region was also found in 216, 200, 174, and 164 bp alleles.  相似文献   
69.
Summary Freshly cut leaves of Kohleria eriantha and K. x Longwood were exposed to a wide range of gamma irradiation doses and allowed to root and form adventitious buds. K. Eriantha could not be successfully propagated from leaf half cuttings. Longwood produced a small number of adventitious plantlets as compared to other Gesneriads. Colchicine treatments reduced leaf half survival in Longwood by more than 50%. Leaf halves exposed to low and moderate doses of gamma irradiation showed increased overall plantlet production compared to nonirradiated leaf halves.Of the mutation parameters calculated, the number of mutants per 100 surviving leaf halves appears to be the most useful since it relates the number of mutants within a dose to the number of surviving leaf halves, the number of mutants to the number of plants produced, and the number of mutants within doses to control values.Using the criteria, number of mutants per 100 surviving leaf halves, optimum production of all mutants, of useful and of dwarf mutants was obtained at 2.5 kR for noncolchicine treated leaf halves and 1.5 to 3.0 kR for colchicine treated leaf halves.Of the adventitious plantlets produced, 13.8% were classified as mutant types. Mutant plants were found in radiation dose levels up to 5.5 kR. The array of mutants produced was skewed toward plant habit and flower characteristic mutants with several leaf characteristic, lethal, and polyploid mutants observed. A high frequency of mutants, 10 of 93 plants, occurred in the nonirradiated controls. Four sectorial chimeras were identified from both control and irradiation exposed groups. Several potentially useful flower color and dwarf mutants have been selected for further study. Adventitious buds may have developed from callus at petiole and leaf-vein bases. Colchicine treatments severely inhibited adventitious plantlet production and because of this could not be used as a criterion to identify the origin of adventitious buds. Conclusive determination of the organogenesis of adventitious buds from Longwood leaf halves could not be made. Mutant plantlets formed from adventitious buds on detached leaf halves of Longwood appear to arise from single cells as has been found with other Gesneriads.Scientific Journal Series Article No. 10 330 of the Minnesota Agricultural Experiment Station.  相似文献   
70.
Southern populations of the European minnow fromremote oligotrophic mountain lakes along an Alpinenorth-south transect accumulated more p,p DDE andPCBs than northern populations. As these semi-volatileorganochlorines predominantly evaporate in warmcountries, higher rates of condensation (deposition)are assumed to occur in the southern slopes of theAlps. The higher accumulation of lead and cadmium insouthern population is rather attributed to geogenicand specific environmental impacts than to atmosphericdeposition. Increasing liver ratios of [glutathionedisulfide]/[glutathione], a potential indicator foroxidative stress, from north to south reflect thegenerally higher toxic load at remote sites at thesouthern edge of the Alps. However, histopathologicalchanges in the liver did not correlate withaccumulated toxicants indicating that deposition doesnot lead to severe lesions but induces specificmechanisms for detoxification.  相似文献   
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