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1.
Marsh white seedless grapefruit were treated with the 2-diethylaminoethanol esters of the following acids: benzoic, phenylacetic, hydrocinnamic, 4-phenylbutyric, 5-phenylvaleric, valeric, hexanoic, heptanoic, octanoic, nonanoic, 5-chlorovaleric, cyclohexanecarboxylic, phenoxyacetic, p-chlorophenoxyacetic, 3-phenoxypropionic, cinnamic and p-chlorocinnamic. Several of these esters, in particular the hexanoate, 4-phenylbutyrate and cinnamate, caused the accumulation of large amounts of β-carotene. The effects of the hexanoate and of 2-phenoxytriethylamine, which causes only lycopene accumulation, were studied as functions of time. The hexanoate caused the rapid accumulation of lycopene during the first day. The amount of lycopene then began to decrease and that of β-carotene increased until, after 14 days, β-carotene was the major pigment. 2-Phenoxytriethylamine caused rapid lycopene accumulation during the first day and a slow steady increase afterwards. Thus, the mode of action of the β-carotene inducers may be similar to that of the lycopene inducers except that the former are probably rapidly hydrolysed by the esterase(s) in the flavedo, so that they no longer inhibit the cyclase(s), and β-carotene is accumulated at the expanse of lycopene. 相似文献
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Fifteen amines having a profound effect on carotenogenesis in Marsh seedless grapefruit are reported. The compounds fall into three series: Et2N(CH2)nMe (n = 4–8), Et2N(CH2)nPh (n = 1–5), and Et2NCH2CH2OC6H4R (R=H, p-Me, p-Et, p-iso-Pr, p-tert-Bu), There was up to an 11-fold increase in the total carotene content. Lycopene, not normally accumulated, became a major pigment. The inducing ability of the amines on carotenoid biosynthesis is correlated with the octanol-water partition coefficient. The mode of action appears to be similar to that of 2-(4-chlorophenylthio)triethylamine hydrochloride. 相似文献
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Koltunow Anna M. Brennan Peter Bond James E. Barker Susan J. 《Molecular breeding : new strategies in plant improvement》1998,4(3):235-251
Seedlessness is a highly desirable characteristic in fresh fruit. Marketability of a fruit as seedless does not require complete absence of seeds as long as the seed structures are imperceptible during consumption. Chimaeric genes comprised of soybean -conglycinin seed storage protein gene promoters linked to the bacterial RNase gene, Barnase, were tested for their efficacy to cause seed death and decrease seed size in tobacco and Arabidopsis. These species were used because they undergo two distinct seed developmental pathways and produce albuminous and exalbuminous seeds, respectively. In both species, the death of embryo and endosperm tissues occurred, resulting in a dominant seed lethal phenotype with segregation distortion. Reduction in seed size was only observed in Arabidopsis seeds and the phenotype resembled that of stenospermocarpic seeds in grape. Some transformants of both species were male-sterile and this correlated with the expression of the gene in anthers indicating that expression of the gene is not strictly seed-specific. The promoters also direct expression of a linked GUS gene to Citrus embryos of various developmental stages, and Citrus forms exalbuminous seeds, therefore, the Barnase constructions may be useful in eliciting a reduction in seed size of around 75% of the seeds found in the fruit. This may be sufficient to warrant marketing as less seedy if trials in the cultivar of interest indicate that the smaller seeds are less detectable to the consumer. Abbreviations: GUS, -glucuronidase; PCR, polymerase chain reaction; DMSO, dimethyl sulfoxide; DTA, diphtheria toxin-A chain; CFDA, 5(6)-carboxy-fluorescein di-acetate; CG, -conglycinin; DAP, days after pollination; FAA, formaldehyde-acetic acid alcohol fixative. 相似文献
4.
应用柑橘异源四倍体杂种花粉生产瘪籽沙田柚果实 总被引:1,自引:0,他引:1
以3个柑橘异源四倍体体细胞杂种(即四倍体粗柠檬与哈姆林甜橙体细胞杂种,简称"HR";酸柚与粗柠檬体细胞杂种,简称"SR";墨西哥来檬与伏令夏甜橙体细胞杂种,简称"KV")为父本,分别与二倍体单胚性沙田柚进行有性杂交,在生产上获得瘪籽沙田柚果实,并对果实品质进行分析(以四季柚花粉亲本为对照)。结果表明:授予柑橘异源四倍体杂种花粉的果实种子败育十分明显,果实瘪籽率达41.4%~96.0%,与对照间的差异极显著(P0.01);但果实单果重、果肉重、果皮重、果皮厚和果形指数与对照间无显著性差异(P0.05);果实可溶性固形物、全糖、Vc和可滴定酸含量与对照也无明显变化,且较适合于瘪籽沙田柚果实生产的体细胞杂种是HR和SR。 相似文献
5.
Broad-based studies of gymnosperms and angiosperms reveal consistent and functionally significant correlations among foliar traits such as leaf mass per area (LMA), maximum photosynthetic rate (A(area)), foliar nitrogen (N(area)), foliar chlorophyll (Chl) and leaf longevity. To assess the generality of these relationships, we studied 20 fern species growing in the understorey of a temperate deciduous forest. We found that foliar N(area) increases with LMA, and that foliar N(area) and A(area) are positively correlated with one another, as are foliar N(area) and Chl. The ferns in general have very low LMA compared with most seed plants; A(area), N(area) and Chl are below median values for seed plants but are not extreme. Species with overwintering fronds have significantly higher LMA than species with fronds that senesce at the end of the growing season, as well as a significantly higher C : N ratio in frond tissue and relatively high foliar N on an areal basis. Correlations among foliar traits associated with gas exchange in these forest understorey ferns are in accordance with patterns reported for seed plants, suggesting a high degree of functional constraint on the interrelationships among key elements in foliar design. 相似文献
6.
无核葡萄胚挽救影响因素的研究 总被引:5,自引:0,他引:5
分别以‘底莱特’和‘大粒红无核’自交、‘红宝石无核’ב新郁’和‘爱莫无核’ב黑奥林’胚珠为材料进行无核葡萄胚挽救影响因素的研究。结果显示:(1)‘底莱特’自交和‘红宝石无核’ב新郁’胚珠剥胚后萌发率分别为11.4%和10.0%,高于横切胚珠情况下的萌发率(5.5%、0.6%);(2)用Nitsch培养基培养的‘大粒红无核’自交和‘爱莫无核’ב黑奥林’胚珠的胚萌发率分别为9.5%和5.6%,胚状体诱导率分别为6.3%和3.9%,明显高于ER培养基的萌发率。结果表明:剥胚有利于无核葡萄胚的萌发;Nitsch比ER培养基更有利于胚萌发和胚状体诱导;同时,由于杂交亲本染色体倍性的差异导致胚萌发率不同,表现为:二倍体无核自交>二倍体无核×二倍体有核>二倍体无核×四倍体有核。 相似文献
7.
J.?W.?GrosserEmail author F.?G.?GmitterJr. 《In vitro cellular & developmental biology. Plant》2005,41(3):220-225
Summary Although somatic hybridization techniques are being ignored by variety improvement programs for most commodities, their contribution
to citrus variety improvement continnes to expland and with increasing complexity. Citrus is, one of the few commodities where
somatic hybridization is reaching its predicted potential, as somatic hybrids are now possible from most desirable parental
combinations. Somatic hybrid citrus plants have been produced from more than 250 parental combinations, including more than
130 at the CREC. The CREC hybrids include 34 from sexually compatible intergeneric combinations, 16 from sexually incompatible
combinations, and 81 interspecific combinations. The objective of this report is to demonstrate the impact of somatic hybridization
on citrus improvement programs, and to discuss its potential with other commodities. For citrus scion improvement, several
applications are aimed at the development of improved seedless fresh fruit varieties, and these include symmetric somatic
hybridization, haploid+diploid fusion, targeted cybridization to transfer cytoplasmic male sterility (mtCMS) from Satsuma
mandarin, and triploidy via interploid crosses using somatic hybrid allotetrapoid breeding parents. For rootstock improvement
symmetric somatic hybridization provides an opportunity to hybridize complementary rootstocks without breaking up successful
gene combinations. Rootstock somatic hybridization is providing opportunities for improving disease and inseet resistance,
soil adaptation, and tree size control. Wide somatic hybridization provides an opportunity for gene transfer from related
species, including some that are sexually incompatible. Extensive field research on citrus somatic hybrid rootstocks combined
with emerging molecular analyses of citrus has allowed for the development of additional strategies for rootstock improvement.
These include rootstock breeding and selection, at the tetraploid level using somatic hybrid parents, and the resynthesis
of important rootstocks at the tetraploid level via fusion of selected superior parents. Ongoing examples of each strategy
will be provided, along with ideas for extending the technology to other commodities. 相似文献
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无核香味葡萄胚挽救育种研究 总被引:1,自引:0,他引:1
为创制无核香味葡萄新种质,该研究以7个无核葡萄品种为母本,4个玫瑰香味品种为父本,配置了9个杂交组合。田间杂交后,通过胚挽救技术离体培养杂种胚珠,使胚珠中幼胚继续发育,继而在幼胚萌发成苗后利用无核标记对F1代株系进行无核性状的早期检测,同时对杂种幼苗进行温室炼苗,最终移栽大田。结果表明:(1)利用胚挽救技术获得365个胚挽救株系,移栽大田并成活182株杂种苗。(2)对其中72个株系利用无核基因探针GSLP1-569与无核分子标记SCF27-2000进行无核性状检测,分别检测出8个和38个杂种后代携带无核特异性条带,初步确定为无核株系。(3)杂交组合中以‘红宝石无核’、‘火焰无核’、‘昆香无核’为母本的组合成苗率相对较高,较适宜做母本;香味品种中‘玫瑰香’更适合做为父本选育香味无核种质。(4)以‘火焰无核’和‘昆香无核’为母本的杂交组合分别在授粉后的43d和51d采样,胚发育率(6.96%~8.54%和16.92%~18.13%)和成苗率(6.45%和8.75%~10%)较高;‘红宝石无核’ב玫瑰香’、‘莫莉莎无核’ב玫瑰香’和‘波尔莱特’ב玫瑰香’3个组合分别在授粉后59~60d、54d、52d采样,胚挽救育种效果较好;杂交组合‘克瑞森无核’ב巨玫瑰’和‘奇妙无核’ב昆香无核’胚败育时期分别为授粉后39d和48d。(5)幼胚发育至子叶型胚时最易成苗,延长胚珠离体暗培养时间显著增加了畸形胚比率。研究认为,葡萄胚挽救育种过程中,胚珠离体培养时间在8~10周为宜。 相似文献