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81.
Vinayak Singh Namita Singh Chauhan Mohit Singh Asif Idris Raju Madanala Veena Pande Chandra Sekhar Mohanty 《Plant signaling & behavior》2014,9(10)
An in vitro method of multiple shoot induction and plant regeneration in Psophocarpus tetragonolobus (L.) DC was developed. Cotyledons, hypocotyls, epicotyls, internodal and young seedling leaves were used as explants. MS media supplemented with various concentrations of either thidiazuron (TDZ) or N6-benzylaminopurine (BAP) along with NAA or IAA combinations were used to determine their influence on multiple shoot induction. MS media supplemented with TDZ induced direct shoot regeneration when epicotyls and internodal segments were used as explants. TDZ at 3 mg L−1 induced highest rate (89.2 ± 3.28%) of regeneration with (13.4 ± 2.04) shoots per explant. MS media supplemented with BAP in combination with NAA or IAA induced callus mediated regeneration when cotyledons and hypocotyls were used as explants. BAP (2.5 mg L−1) and IAA (0.2 mg L−1) induced highest rate (100 ± 2.66%) of regeneration with (23.2 ± 2.66) shoots per explant. Mature plants produced from regenerated shoots were transferred successfully to the greenhouse. In a comparative study, the phenolics contents of various parts of greenhouse-grown plants with that of in vitro-raised plants showed significant variations. 相似文献
82.
E. Albano Pérez J.A. Coetzee T. Ruiz Téllez M.P. Hill 《South African Journal of Botany》2011,77(3):795-800
We investigated water hyacinth seed banks in several aquatic systems in South Africa. Fifteen sites, mainly in the Eastern and Western Cape provinces, were surveyed from August to October 2009. Soil seed density varied between 0 and 2534 seeds/m2 but did not differ significantly between the type of waterbody (impoundment vs. river) or the history of control carried out at a site. Average germination was 54.17% with very fast velocities (Vigour Index = 36.66) and maximum germination around three days. Although we demonstrated the existence of an important reservoir of seeds, results from this study indicated that a combination of factors such as water fluctuation, eutrophication and seed decomposition might have had a great influence on dispersal and persistence of seeds. 相似文献
83.
郫县豆瓣发酵过程的微生物多样性及溯源分析 总被引:1,自引:1,他引:0
[目的] 解析郫县豆瓣及其酿造半成品-蚕豆醅与辣椒醅微生物多样性和来源,探究郫县豆瓣酿造过程风味化合物特征。[方法] 采用高通量测序法测定蚕豆醅、辣椒醅与混合醅(蚕豆醅-辣椒醅混合物,发酵成熟形成郫县豆瓣)在酿造过程中的微生物群落结构;利用高效气相质谱与高效液相色谱高通量检测蚕豆醅及辣椒醅中基础理化指标及挥发性、非挥发性风味化合物浓度;利用多种生物信息学分析方法对混合醅酿造微生物及风味化合物进行溯源。[结果] 微生物方面:44%–59%的混合醅细菌来源于辣椒醅,5%–22%的混合醅细菌来源于蚕豆醅,其他混合醅细菌来源未知。同时,42%–77%的混合醅真菌来源于辣椒醅,2%–18%的混合醅真菌来源于蚕豆醅,其他混合醅真菌来源未知。另外,16个细菌属由辣椒醅特异性贡献;2个细菌属及2个真菌属由蚕豆醅特异性贡献。化合物方面:1-辛烯-3醇(1-octen-3-ol)、苯乙醛(phenylacetaldehyde)、异丁醛(isobutyraldehyde)、苹果酸(malic acid)与糠醛(furfural)仅由蚕豆醅贡献。辣椒素(capsaicin)、3-甲基-1-丁醇(3-methyl-1-butanol)、已醇(hexanol)与异丁醇(isobutanol)仅由辣椒醅贡献。[结论] 郫县豆瓣发酵中大部分微生物来源于辣椒醅,大部分发酵底物(氨基酸及葡萄糖)来源于蚕豆醅。两种发酵半成品均特异性贡献微生物及风味化合物,形成郫县豆瓣的独特风味密码。 相似文献
84.
广西原产和外引蚕豆种质资源鉴定评价 总被引:3,自引:0,他引:3
在广西南宁对242份引自 ICARDA 和我国云南、河北、江苏、广东、甘肃及广西的蚕豆种质资源进行了连续3年的农艺性状鉴定和连续2年的抗病性鉴定。从中筛选出适宜在广西试种利用的8份优良资源。鉴定结果表明,引自 ICAR-DA 和甘肃、河北、江苏的材料大部分在广西结实很少或者没有结实,来自纬度相近地区的广东、云南的材料结实基本正常,来自广西的材料最为正常,说明蚕豆的生态适应范围狭窄,具有很强的地域生态特点。 相似文献
85.
86.
三种瘤背豆象幼虫酯酶同工酶的比较研究 总被引:7,自引:2,他引:5
本研究采用聚丙烯酰胺凝胶垂直板型电泳法 ,分析了 3种瘤背豆象属豆象 :绿豆象 Callosobruchuschinensis L.、灰豆象 C.phaseoli ( Gyllenhal)、鹰嘴豆象 C.analis ( Fabricius)幼虫的酯酶同工酶。从酶谱的酶带数、迁移率、酶活性强弱 (酶带染色深浅 )、酶含量 (酶带宽窄 )等方面的比较发现 ,3种瘤背豆象属豆象幼虫的酯酶同工酶酶谱具有明显的差异。由此探讨利用酯酶同工酶电泳法鉴别豆象的可能性 相似文献
87.
Felicia Hosein 《Plant Molecular Biology Reporter》2001,19(1):65-65
Pachyrhizus erosus is a tuberous legume native to Central America that has great potential for development as a food crop. It produces both
protein rich grain and starch filled tubers. There are two major limitations to its dietary use, the high levels of rotenone
found in the grains and the low starch content of the tubers, both of which must be addressed, for development of the crop.
The low variability of the existing gene pool of the genus limits the use of conventional plant breeding to address these
problems. Genetic engineering technology is, therefore, being adopted. For this purpose, an efficient means of RNA isolation
from yam bean tissues was developed. The quality of RNA obtained by this method was tested byin vitro translation and was sufficient for use in RT-PCR. 相似文献
88.
We investigated the response of the specialist insect predator Oligota kashmirica benefica (Coleoptera: Staphylinidae) to volatiles from lima bean leaves infested with the spider mite Tetranychus urticae (Acari: Tetranychidae), both in a Y-tube olfactometer and in a field in Kyoto, Japan. Adult male and female predators were significantly more attracted to T. urticae-infested leaves than to clean air. Adult male and female predators were not more attracted to uninfested leaves, artificially damaged leaves, or the spider mites and their visible products when compared to clean air. In a field trap experiment, 12 adult predators were caught in three traps containing T. urticae-infested lima bean plants over 13 days, whereas no adult predators were trapped in three traps containing uninfested lima bean plants during the same period. These results showed that O. kashmirica benefica adults responded to herbivore-induced plant volatiles from T. urticae-infested lima bean leaves under both laboratory and field conditions. 相似文献
89.
Influence of plant development and environment on transgene expression in potato and consequences for insect resistance 总被引:8,自引:0,他引:8
Down Rachel E. Ford Louise Bedford Simon J. Gatehouse Laurence N. Newell Christine Gatehouse John A. Gatehouse Angharad M.R. 《Transgenic research》2001,10(3):223-236
Clonal replicates of different transformed potato plants expressing transgene constructs containing the constitutive Cauliflower Mosaic Virus (CaMV) 35S promoter, and sequences encoding the plant defensive proteins snowdrop lectin (Galanthus nivalis agglutinin; GNA), and bean chitinase (BCH) were propagated in tissue culture. Plants were grown to maturity, at first under controlled environmental conditions, and later in the glasshouse. For a given transgene product, protein accumulation was found to vary between the different lines of clonal replicates (where each line was derived from a single primary transformant plant), as expected. However, variability was also found to exist within each line of clonal replicates, comparable to the variation of mean expression levels observed between the different clonal lines. Levels of GNA, accumulated in different parts of a transgenic potato plant, also showed variation but to a lesser extent than plant–plant variation in expression. With the majority of the clonal lines investigated, accumulation of the transgene product was found to increase as the potato plant developed, with maximum levels found in mature plants. The variation in accumulation of GNA among transgenic plants within a line of clonal replicates was exploited to demonstrate that the enhanced resistance towards larvae of the tomato moth, Lacanobia oleracea L., caused by expression of this protein in potato, was directly correlated with the level of GNA present in the plants, and that conditions under which the plants were grown affect the levels of GNA expression and subsequent levels of insect resistance. 相似文献
90.
大豆是豆类植物中最早发现存在蛋白酶抑制子的 ,由于其存在影响了豆类的利用价值 ,因此研究人员一直在寻找着解决办法。采用加热处理方法不能彻底钝化豆类蛋白的蛋白酶抑制子活性 ,且豆类蛋白的含硫氨基酸主要存在于各类蛋白酶抑制子中 ,从豆类蛋白中除去抑制子蛋白将大大降低其营养效价。本研究的目的是试图寻找一种可在常温下降解豆类胰蛋白酶抑制子的蛋白酶 ,从而钝化豆类的胰蛋白酶抑制活性。在前期工作中 ,我们发现枯草杆菌蛋白酶 (Sub tilisin)可在在常温下降解花生及大豆胰蛋白酶抑制剂[1] ,近期我们的研究表明 ,Alca… 相似文献