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51.
52.
Hitomi NAKABAYASHI Yasuyuki YAMAJI Satoshi KAGIWADA Masashi UGAKI Shigetou NAMBA 《Journal of General Plant Pathology》2002,68(2):173-176
The complete nucleotide sequence was determined for genomic RNA of White clover mosaic virus (WClMV-RC) isolated from red clover (Trifolium pratense) in Japan, It is 5843 nucleotides in length, excluding the poly(A) tail at the 3' terminus. Similar to other potexviruses,
it contains five open reading frames (ORFs 1 through 5), which putatively encode an RNA-dependent RNA polymerase (RdRp) (147
kDa), a triple gene block (TGB) (26 kDa/13 kDa/7 kDa), and a coat protein (CP) (22 kDa), respectively. The deduced amino acid
sequence of the WClMV-RC CP was identical to that of WClMV-O, one of two New Zealand isolates, but only 85% identical to that
of WClMV-M, the other New Zealand isolate, because of heterogeneity in the C-termini of CP amino acid sequences. The implication
of this CP heterogeneity is discussed.
Received 30 August 2001/ Accepted in revised form 11 January 2002 相似文献
53.
54.
辣椒疫病发病主导因素及综合防治技术研究 总被引:2,自引:0,他引:2
通过3a在多年辣椒重茬地的田间试验及调查研究,基本明确了辣椒疫病发生与灌水方法、栽培方式、降水、中心病株的出现等主导因素的关系。提出了栽培防病、化学治疗的综防技术,达到控病增产的目的。 相似文献
55.
J Petersen 《Weed Research》2003,43(1):33-39
Summary The experiments were carried out in the two spring barley fields of the organic six-course cattle:crop rotation at Foulumgaard, Denmark. The weed density was 300 and 1800 plants m−2 respectively. Pig slurry was applied by hand in microplots by four methods: broadcasting followed by incorporation, or injected in bands to depths of 5, 10 or 15 cm. Spring barley and weeds were sampled separately six times during the tillering and elongation phase of the spring barley. The effect of application method on dry-matter (d.m.) production, nitrogen uptake and recovery of applied nitrogen in the spring barley and the weeds is reported. Slurry banding halved the weed d.m. and weed N uptake compared with broadcasting, irrespective of weed density. Weeds recovered up to 12% of the applied nitrogen, which made them a significant competitor when the slurry was broadcast and incorporated. Banding by direct injection reduced the slurry:soil contact and the weed:crop competition balance for applied nitrogen moved in favour of the crop. Thus, the crop recovery of applied nitrogen at the end of the sampling period was increased from approximately 45% for broadcast and incorporated to approximately 50% for injected slurry, and coincidental weed recovery was reduced to a maximum of 5%. As the nitrogen supply normally affects plant d.m. production, banding of slurry might well improve crop competitiveness and its tolerance to mechanical weed control. 相似文献
56.
鸡腿蘑菌丝体的同工酶研究 总被引:7,自引:1,他引:7
用8种不同培养基配方,培养鸡腿蘑菌丝体,其同工酶分析结果表明,鸡腿蘑菌丝体酯酶(EST)同工酶谱差异明显,过氧化物酶(POD)同工酶谱差异明显。 相似文献
57.
在陕西省关中土娄土区布置线辣椒、甘蓝、白菜、芹菜钾肥大田试验,研究不同蔬菜对钾肥的肥效反应。结果表明,增施钾肥可使蔬菜硝态氮含量降低11.8%~116.0%,维生素C含量增加0.4~147.4mg/kg;产量增加9.3%~33.8%;明显促进营养生长和生殖生长;400cm深土壤剖面硝态氮累积量减少22.7~48.0kg/hm2,尤其在80~220cm剖面减少最为明显。 相似文献
58.
Leaf explants of Caladium ‘Pink Cloud’ were cultured in vitro on MS medium containing various auxins (NAA, IBA, IAA, 2,4,5-T and 2,4-D) in combination with cytokinin (BA). NAA gave the most vigorous in vitro propagation of this plant, and only 15% of the plants were leaf-colour variants on the medium containing 0.5 μmol NAA. Leaf colour variation was observed in all plants regenerated on the medium containing 2,4-D at 0.5–4.5 μmol. In hormone-free medium, only a few leaf-colour variants (6%) occurred, but the rate of plant regeneration was very low. Application of 0.5 μmol NAA together with 4.5 μmol BA seemed to be the most appropriate for in vitro propagation of Caladium ‘Pink Cloud’ with only a few leaf-colour variants. 相似文献
59.
In order to optimise production of the edible flower buds produced by myoga (Zingiber mioga Roscoe) a greater understanding of the growth and development of the plant and factors influencing flower initiation and development are required. The vegetative growth phase in myoga was characterised by a distinct period of pseudostem development from the planted rhizome piece followed by an extended period of rhizome growth from both the base of pseudostems and the planted rhizome piece. The transition from pseudostem formation to the initiation of rhizome growth occurred at the same time as the dry weight of the planted rhizome piece ceased to decline. Flower bud initiation and development occurred over an extended period, beginning soon after the commencement of new rhizome growth and ending prior to foliage senescence. Flower buds were observed at the terminal meristem of first, second, third and fourth order rhizomes. Increasing temperatures stimulated both increased vegetative growth and flower bud initiation and development. Low flower bud yields recorded under conditions of low temperature were the result of reduced rate of floral initiation and not abortion of flower buds. Increased shading of plants grown under glasshouse conditions resulted in reduced flower bud yield and similarly the response resulted from decreased initiation rather than abortion. 相似文献
60.
Clone identification and genetic relationship among vine cacti from the genera Hylocereus and Selenicereus based on RAPD analysis 总被引:1,自引:0,他引:1
Clones of Hylocereus and of Selenicereus species were distinguished from each other by the banding pattern generated by one to nine 10-mer oligonucleotide primers in the random amplified polymorphic DNA (RAPD) reaction. RAPD analysis was also applied to estimate the genetic relationship among five Hylocereus and nine Selenicereus species. A dendrogram was constructed based on a data matrix of 173 polymorphic bands originated by nine primers. Two groups were identified, one consisting of Hylocereus species and the other consisting of Selenicereus species. These results are consistent with the accepted taxonomic classification of the genera studied. The principal coordinate analysis (PCO), i.e. the plot drawn on the basis of the RAPD data, clearly distinguished between three groups, namely, Hylocereus species, S. megalanthus and the rest of the Selenicereus species studied. PCO thus strongly support the notion that the tetraploid S. megalanthus is an exception among the Selenicereus group. The RAPD results support our hypothesis regarding the allopolyploid (rather than autopolyploid) origin of this species. 相似文献