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41.
通过矮花叶病抗性鉴定筛选出玉米高抗自交系黄野四-3和高感自交系8112.遗传分析显示矮花叶病抗性表现为显性遗传.利用SSR分子标记,结合群体分离分析方法(BSA),对抗矮花叶病基因进行定位,筛选获得了与玉米抗矮花叶病基因位点连锁的SSR标记,并将该基因定位于第3连锁群,与两侧的Bnlg1035和Umc2266分子标记遗传距离分别为8.02 cM和3.04 cM.这一研究结果为快速筛选抗矮花叶病玉米新种质,培育抗性新品种提供了理论依据,为抗矮花叶病基因的分子标记辅助育种和抗病基因克隆奠定了基础. 相似文献
42.
重金属胁迫对2种地被竹抗氧化酶与脂质过氧化的影响 总被引:3,自引:1,他引:3
采用盆栽法对4种重金属(Cd2+、Pb2+、Cu2+、Zn2+)胁迫下的菲黄竹与菲白竹叶片中的超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性及脂质过氧化产物(MDA)进行了研究。结果表明,菲黄竹的SOD、POD、及CAT活性随着重金属浓度的增加总体趋势是先增大,之后降低,最后又增大;而菲白竹则是先升高,后降低;过氧化产物(MDA)则于酶活性的变化趋势相反。表明重金属胁迫下,2种地被竹体内的抗氧化酶活性被诱导,且菲白竹比菲黄竹有更强的耐重金属胁迫性。 相似文献
43.
44.
Aamir Lal Eui-Joon Kil Vo T. B. Thuy Chairina Fadhila Phuong T. Ho Hee-Seong Byun Hang T. Dao Ji-Kwang Kim Sukchan Lee 《Plant pathology》2020,69(6):1026-1033
Milk vetch dwarf virus (MDV) is an important member of the genus Nanovirus and is transmitted by the aphid Aphis craccivora. MDV has multiple single-stranded DNA genome components, each approximately 1 kb, and two or three alpha-satellite molecules. It mainly infects plants of the legume family Fabaceae. Recently, papaya (Carica papaya) collected in Yesan, South Korea, displaying symptoms of leaf yellowing and dwarfism, was identified as a new host for MDV. To examine the geographical distribution of MDV, papaya samples with symptoms were harvested in South Korea, Vietnam, and Taiwan in August 2018, along with tomato and pepper samples grown in adjacent fields in Vietnam. The results revealed the presence of MDV not only in papaya but also in pepper and tomato. This MDV infection in members of the Solanaceae family was confirmed by Southern blot hybridization performed using a PCR product of segment S as a probe. Based on sequence analysis of three MDV components (M, S, and C3), we verified the presence of three different isolates of MDV in these three countries and homology between sequences of isolates from papaya and from members of the Solanaceae from Vietnam. Taken together, our results clearly demonstrate MDV infection in Vietnam and Taiwan for the first time and confirm that MDV can infect economically important pepper and tomato. 相似文献
45.
P. Oyarzun M. Gerlagh A. E. Hoogland 《European journal of plant pathology / European Foundation for Plant Pathology》1993,99(1):35-44
The relation between the frequency of legume crops in a rotation and the root rot severity in pea was examined in a field survey. Additionally, greenhouse experiments were performed with soil samples from legume rotation trials or from farmers' fields. The frequency of pea crops in current rotations proved to be much less than the recommended value of one in six years. The correlation between pea root rot and the number of years that pea or other legumes were not grown on the field under consideration (called crop interval) was weak. Root rot severity correlated better with the frequency of peas or legumes in general over a period of 18 years, but the frequency still explained only a minor fraction of the variation in disease index. Some experimental data pointed to the occurrence of a highly specific pathogen microflora with continuous cropping of only one legume species, but this phenomenon probably does not occur in farmers' fields. In field samples, root disease index for pea correlated well with that for field bean. The survival of resting structures of pathogens such asAphanomyces euteiches probably explains why the frequency of legume cropping has a higher impact than crop interval on root disease incidence. Pea-free periods and legume frequencies have a poor predictive value for crop management purposes. 相似文献
46.
Two series of field trials were performed at three sites in Schleswig-Holstein between 1981 and 1988 to inquire into the yield structure of European winter types of Vicia faba L. and to compare their yield potential with that of spring types. Due to low winter survival, 6 winter types could be evaluated only in 4 environments in dependence of 1–3 sowing times (series α: seed rate 30/m2) and 1 winter type in 5 environments in dependence of 3 sowing times and 3 seed rates (series β: seed rate 15, 30, 45/m2). Seed yield of winter type averaged 410 g/m2 (D.M.) surpassing spring types by about 14 %. Environments caused a considerable variation in yield (275–620 g/m2) and in each yield component of winter types, while sowing dates and seed rates hardly affected the components seeds/pod and seed weight, which displayed stable genotypic rank orders. Compensative forces among the components plants/m2, tillers/plant and pods/tiller, were established. Plant densities of less than 10/m2 in spring, generally led to seed yield below 350 g/m2. Variation between 15–30 plants/m2 due to environments, sowing times or seed rates were frequently not fully compensated by tillering of plants, but often variation of the thus formed yield potential was reduced by pod set of tillers resulting in 210–270 pods/m2. The direction of correlations of pods/tillers with tillers/plant and plants/m2 differed due to experimental conditions whereas negative correlations between pods/tiller and tillers/ m2 were generally evident. Tillering was significantly influenced by the sowing time, though the increase because of early sowing was often covered by compensative effects of different plant densities. A genotypic capability to produce reproductive tillers was demonstrated using an approach which considered different plant densities and compensative forces. Neither a genotypic capability of tillers to set pods nor direct effects of environments or sowing time on pod set were established. 相似文献
47.
A. A. Bakr 《Plant foods for human nutrition (Dordrecht, Netherlands)》1996,49(1):83-92
In order to study the effects of main technological pretreatments practised for preparing Egyptian faba bean products, i.e. decortication as well as soaking and germination followed by dehulling on the nutritional value, series of experiments were carried out. Such pretreatments had a significant effect on the changes in the chemical composition of faba beans. The proportion of the removed hulls reached generally about 14%. Data revealed also pronounced improvements on the nutritive value as a result of all studied pretreatments, especially germination being the most effective. Chemical scoring of all determined essential amino acids was >60, except methionine and cystine showed the lowest score (<20). Germinated seeds had the highest chemical score for the restricting amino acids beside the lowest GDR value [Grams consumed of product to cover the daily requirements for adult man in protein (63 g) and in energy (2900 kcal)]. All pretreatments caused a significant decrease in the antinutritional factors, especially soaking followed by dehulling, whereas decortication led to a significant increase in phytic acid content. 相似文献
48.
水稻叶色白化转绿及多分蘖矮秆基因hw-1(t)的图位克隆 总被引:1,自引:0,他引:1
通过增加作图群体的样本量, 将控制水稻白化转绿和多分蘖矮秆的基因hw-1(t)定位在第4染色体长臂2个InDel标记HW36和HW7之间24.9 kb的物理距离内, 该区域含有5个阅读框架。测序及酶切分析表明, 突变体hfa-1仅在LOC_Os04g57320产生一个碱基(G→A)的突变, 导致翻译提取终止, 推断LOC_Os04g57320为hw-1(t)。进一步分析发现hw-1(t)在水稻基因组中为单拷贝, 与拟南芥im和番茄PTOX基因同源性较高, 但在转录子和蛋白质结构上存在一定差异;基因表达分析显示HW-1(t)属组成型表达基因, 表达不受光照影响。 相似文献
49.
从单头灰飞虱中检测水稻黑条矮缩病毒简单快速的方法 总被引:1,自引:0,他引:1
报道了2种从介体灰飞虱中检测水稻黑条矮缩病毒的分子生物学方法。其中直接捕获RT-PCR经简单的样品处理后可以从单头虫粗提液的10^-3中检测到病毒,并具有快速、简单优点;单头灰飞虱样品汁液点膜或虫体直接积压在膜上杂交检测具有简单、经济和快速的特点,可以检测田间批量样品,用于病害流行研究的测报。研究中60%-70%杂交检测阳性的介体生物学接种结果为阴性,反映了介体灰飞虱带毒率与传毒能力的差异。 相似文献
50.