黄瓜果肉色的遗传分析

以1份西双版纳黄瓜和2份普通黄瓜自交系为试验材料配制2个杂交组合,并构建4世代群体(P1、P2、F1、F2).分别采用目测分级、色差仪测定a值和b值以及HPLC方法测定β-胡萝卜素含量等4个指标,研究黄瓜果肉色性状的遗传规律.结果表明:2个杂交组合F2群体的果肉色相关指标呈单峰偏态或双峰分布,表现为主基因+多基因的数量遗传特征.多世代联合分析表明,黄瓜果肉色遗传基本符合两对主基因+多基因模型.两组合8个果肉色相关指标最优模型的F2群体主基因遗传率较高,为76.0%～99.3%,多基因遗传率较低,为0～23.7%.对黄瓜橙黄果肉色的选择应在分离早期世代进行.     

Anatomy of Watermelon Embryo Sacs Following Pollination, Non-pollination or Parthenocarpic Induction of Fruit Development

There is little information on the fate of embryo sacs in plantovules if pollination is prevented. In this study embryo sacsfrom watermelon were observed over a 13 day period followingflowering with (a) normal pollination, (b) non-pollination and(c) induction of parthenocarpic fruit development with naphthaleneacetic acid. Following pollination, and prior to fertilizationapproximately 2 days later, the embryo sacs completed developmentand consisted of two synergids with prominent filiform apparatus,an egg cell, a central cell with two polar nuclei and threeantipodal cells. Sperm nuclei were observed within the embryosac at 2 days and by 4 days the endosperm was proliferating.In the non-pollination treatment the embryo sac was still intactafter 4 days although the antipodal nuclei were becoming hardto distinguish. By 7 days only the two synergids and the eggcell were still well defined, the polar nuclei appeared in somepreparations to be fused, and the antipodals had degenerated.By 10 days the embryo sac was a structure-less watery mass.In parthenocarpic fruit the fate of the embryo sac was similarto that in non-pollinated fruit except that final breakdownwas delayed past 10 days. Maturity of the majority of embryo sacs in an ovary appearedto be contemporaneous with penetration of the pollen tube, andon the basis of the anatomical results it seems possible thatembryo sacs could be fertilized up to 2 days beyond the normaltime. Citrullus lanatus, watermelon, embryo sac, anatomy, pollination, parthenocarpy     

Cytokinin-Induced Parthenocarpic Fruit Development in Tomato Is Partly Dependent on Enhanced Gibberellin and Auxin Biosynthesis

Fruit set of plants largely depends on the biosynthesis and crosstalk of phytohormones. To date the role of cytokinins (CKs) in the fruit development is less understood. Here, we showed that parthenocarpic fruit could be induced by 1-(2-chloro-4-pyridyl)-3-phenylurea (CPPU, an active CK) in tomato ( Solanum lycopersicum cv. Micro-Tom). The fresh weight of CPPU-induced parthenocarpic fruits was comparable with that induced by GA₃. Importantly, CPPU-induced parthenocarpy was found to be compromised by simultaneous application of paclobutrazol (a GA biosynthesis inhibitor), and this effect could be restored by exogenous GA₃. Like pollination, CPPU-induced fruit showed enhanced accumulation of GA₁₊₃ and indole-3-acetic (IAA), which were accompanied by elevated expression of GA biosynthesis genes like SlGPS, SlGA20ox1, SlGA20ox2 and SlGA3ox1, and IAA biosynthesis gene ToFZY. Elevated GAs level in CPPU-induced fruits was also associated with down-regulation of GA inactivation genes, namely SlGA2ox1,2,3,4,5 in comparison with untreated control. These results suggested that CKs may induce parthenocarpy in tomato partially through modulation of GA and IAA metabolisms.     

Early Fruit Development in the Watermelon: Anatomical Comparison of Pollinated, Auxin-induced Parthenocarpic and Unpollinated Fruits

The anatomy of pollinated, auxin-induced parthenocarpic andunpollinated watermelon fruits was observed for nine days afterflowering. Parthenocarpic fruits were larger and had higherfresh weight and percentage water than pollinated fruits atday 1 but the positions were reversed by day 9. Unpollinatedfruits did not increase in size after day 3. Pericarp cells were small, of regular shape and showed no obviouschange with either time or treatment. Cell number increasedin the pollinated and parthenocarpic but not in the unpollinatedfruits. Cells divided in the flesh of the parthenocarpic but not ofthe pollinated fruits which increased in size by cell enlargementonly. Starch, present in the cells of the flesh and placentaat day 0 was absent from the unpollinated fruits at day 6. Ovules grew in both pollinated and parthenocarpic fruits largelydue to cell division in the nucellus and integuments; the pollinatedovules were larger than the parthenocarpic throughout. Embryoand endosperm development occurred in the pollinated but notin the parthenocarpic ovules. Starch was present throughoutthe nine-day period in the integuments of the pollinated andparthenocarpic ovules but was lost from the integuments of theunpollinated ovules by day 6. Pollinated and parthenocarpicovules contributed increasingly to fruit dry weight over thenine-day period. It is suggested that the ovule tissues, in particular the nucellusand integument may exert control over early development in bothpollinated and parthenocarpic fruits.     

植物激素对果树单性结实调控的研究进展

尽管种子与果实的发育过程密切相关,但由于无籽果实提高了果实的品质并延长了货架期,因此无籽果实受到生产者和消费者的广泛青睐。果实的生长受激素调控,而相关研究也初步揭示了激素在单性结实果实形成过程中的作用。本文对单性结实的概念、诱导单性结实的激素种类及功能、诱导机理,以及转基因技术在单性结实果实生产中的应用概况进行了综述,以期为果树单性结实的研究提供参考。     

单性结实和自花结实柑橘果实发育过程中IAA、ZR和GA3含量的变化

对单性结实的龟井温州蜜柑(以下简称龟井)和自花结实的鄂柑1号橘(以下简称鄂柑1号)果实发育过程中不同部位的IAA、ZR和GA3的含量变化进行了测定。结果表明：(1)两品种果皮IAA含量呈相似的变化趋势,均于果实增大期间出现明显高峰,但鄂柑1号的IAA高峰值显著较高;二者果皮ZR含量动态却相反,增大期间龟井果皮ZR的含量相对较高且趋上升,而鄂柑1号却趋下降;二者果皮GA3含量均于增大期间出现类似的上升过程,之后均趋下降。(2)龟井果肉IAA、ZR和GA3含量前期均较高,此后均明显下降并居较低水平;而鄂柑1号果肉IAA和GA3均于增大期间出现明显的上升且含量明显高于龟井,而ZR含量与龟井一样呈下降趋势,但ZR的含量更低。(3)鄂柑1号种子的IAA、ZR和GA3在花后72d均相对较高,之后急剧回落至相对较低的稳定水平。     

Arginine Decarboxylase and Putrescine Oxidase in Ovaries of Pisum sativum L. (Changes during Ovary Senescence and Early Stages of Fruit Development)

Enzymatic activities involved in putrescine metabolism in ovaries of Pisum sativum L. during ovary senescence and fruit set were investigated. Accumulation of putrescine was observed during incubation of extracts from gibberellic acid-treated unpollinated ovaries (young developing fruits) but not in extracts from untreated ovaries (senescent ovaries). Extracts from pea ovaries showed arginine decarboxylase (ADC) activity, but ornithine decarboxylase and arginase activity were not detected. ADC activity decreased in presenescent ovaries and increased markedly after induction of fruit set with gibberellic acid. Increases in ADC activity were also observed with application of other plant growth substances (benzy-ladenine and 2,4-dichlorophenoxyacetic acid), after pollination, and in the slender (la crys) pea mutant. By contrast, putrescine oxidase activity increased in presenescent ovaries but did not increase during early fruit development. All of these results suggest that ADC and putrescine oxidase are involved in the control of putrescine metabolism. Ovary senescence is characterized by the absence of putrescine biosynthesis enzymes and increased levels of putrescine oxidase and fruit development by an increase in ADC and a constant level of putrescine oxidase.     

Induction by Electric Currents of Ethylene Biosynthesis in Cucumber (Cucumis sativus L.) Fruit

The effects of an electric current on ethylene biosynthesis were investigated in cucumber (Cucumis sativus L.) fruit that were producing almost no ethylene. Direct currents at 0.5 to 3.0 milliamperes induced much ethylene synthesis, with a rapid continuous increase in the rate, which reached a peak within 5 to 6 hours and then decreased. The rate of production was greater with a stronger current. Ethylene production was not observed after the use of a sine-wave alternating current (60 hertz) at 3 milliamperes, the magnitude at which a direct current had the greatest effect. The activity of 1-aminocyclopropane-1-carboxylic acid (ACC) synthase and ethylene forming enzyme (EFE) increased before the rise in ethylene production. ACC synthase and EFE were activated sixfold and fourfold, respectively, by 2 hours. The concentration of ACC increased linearly up to 6 hours and then decreased. Ethylene induction by an electric current was suppressed almost completely by the infiltration of the cucumbers with 5 millimolar aminooxyacetic acid, an inhibitor of ACC synthase, and was also suppressed 70% by 5 millimolar salicylic acid, an inhibitor of EFE. The results indicate that the ethylene induced by the direct current was synthesized via the ACC-ethylene pathway as a result of electrical stress, a new kind of stress to be identified.     

Parthenocarpic Fruit Growth Reduces Yield Fluctuation and Blossom-end Rot in Sweet Pepper

The aim of this work was to investigate whether parthenocarpicfruit growth could avoid flushing, i.e. an irregular yield pattern,in sweet pepper. Plants were grown in a greenhouse compartmentfrom April until August. Half of the plants were grown withouta fruit set treatment (control), whereas parthenocarpic fruitswere allowed to develop on the other plants by preventing self-pollinationand applying auxin to the stigma. For node positions 3 to 17,fruit set per node varied between 21 and 55% for control plants[coefficient of variation (CV) = 11%], whereas auxin-treatedplants showed much less variation in fruit set (41–57%;CV = 5%) and average fruit set was higher. In agreement withfruit set, fruit yield was also much more regular in the auxin-treatedplants. Fruit fresh yield varied between 0.2 and 1.0 kg m^-2forcontrol plants (CV = 20%), and between 0.4 and 0.8 kg m^-2forauxin-treated plants (CV = 9%). Results showed that developingseeds in sweet pepper fruits are the main cause of the abortionof new flowers, and irregular fruit set and yield. Parthenocarpicfruit growth resulted in flatter, 30% smaller fruits, becauseof a reduction in fruit growth rate; the duration of fruit growthwas 1 week longer than for fruits from control plants. Parthenocarpicfruits were hardly affected by blossom-end rot (BER) with only1% of fruits being affected compared to 31% in the control.Total dry mass production was the same for treated and controlplants; however, in auxin-treated plants, 50% of the total drymass was allocated to the fruits, compared to 58% in controlplants. Copyright 2001 Annals of Botany Company Abortion, auxin, BER, blossom-end rot, Capsicum annuum L., flushing, fruit set, irregular yield pattern, parthenocarpy, sweet pepper     

黄瓜藤的化学成分研究

从丽江产黄瓜藤甲醇提取物的氯仿部位分离得到9个化合物,经理化和波谱分析鉴定为α-菠甾醇(1)、α-菠甾醇-3-O-β-D-葡萄糖苷(2)、β-谷甾醇(β-sitosterol,3)、豆甾-7-烯-3-O-β-D-葡萄糖苷(4)、22-亚甲基-9,19-环羊毛甾烷-3β-醇(5)、(2S,3S,4R,10E)-2-(2′,3′-二羟基二十四烷酰氨基)-10-十八烯-1,3,4-三醇(6)、(2S,3S,4R,10E)-2-[(2′R)-2-羟基二十四烷酰氨基]-10-十八烯-1,3,4-三醇(7)、(2S,3S,4R,10E)-1-(β-D-葡萄糖苷)-2-[(2′R)-2-羟基二十四烷酰氨基]-10-十八烯-1,3,4-三醇(8)、大豆脑苷(9),除化合物3外,其它化合物均为首次从该植物中分离得到.     

Arginase,Arginine Decarboxylase,Ornithine Decarboxylase,and Polyamines in Tomato Ovaries (Changes in Unpollinated Ovaries and Parthenocarpic Fruits Induced by Auxin or Gibberellin)

Arginase (EC 3.5.3.1) activity has been found in the ovaries and Young fruits of tomato (Lycopersicon esculentum Mill. cv Rutgers).Changes in arginase, arginine decarboxylase (EC 4.1.1.19), and ornithine decarboxylase activity (EC 4.1.1.17) and levels of free and conjugated putrescine, spermidine, and spermine were determined in unpollinated ovaries and in parthenocarpic fruits during the early stages of development induced by 2,4-dichlorophenoxyacetic acid (2,4-D) or gibberellic acid (GA3). Levels of arginase, free spermine, and conjugates of the three polyamines were constant in unpollinated ovaries and characteristic of a presenescent step. A marked decrease in arginase activity, free spermine, and polyamine conjugates was associated with the initiation of fruit growth due to cell division, and when cell expansion was initiated, the absence of arginase indicated a redirection of nitrogen metabolism to the synthesis of arginine. A transient increase in arginine decarboxylase and ornithine decarboxylase was also observed in 2,4-D-induced fruits. In general, 2,4-D treatments produced faster changes than GA3, and without treatment, unpollinated ovaries developed only slightly and senescence was hardly visible. Sensitivity to 2,4-D and GA3 treatment remained for at least 2 weeks postanthesis.     

Pollen Morphology and Boron Concentration in Floral Tissues as Factors Triggering Natural and GA-Induced Parthenocarpic Fruit Development in Grapevine

Parthenocarpic fruit development (PFD) reduces fruit yield and quality in grapevine. Parthenocarpic seedless berries arise from fruit set without effective fertilization due to defective pollen germination. PFD has been associated to micronutrient deficiency but the relation of this phenomenon with pollen polymorphism has not been reported before. In this work, six grapevine cultivars with different tendency for PFD and grown under micronutrient-sufficient conditions were analyzed to determine pollen structure and germination capability as well as PFD rates. Wide variation in non-germinative abnormal pollen was detected either among cultivars as well as for the same cultivar in different growing seasons. A straight correlation with PFD rates was found (R² = 0.9896), suggesting that natural parthenocarpy is related to defective pollen development. Such relation was not observed when PFD was analyzed in grapevine plants exposed to exogenous gibberellin (GA) or abscissic acid (ABA) applications at pre-anthesis. Increase (GA treatment) or reduction (ABA treatment) in PFD rates without significative changes in abnormal pollen was determined. Although these plants were maintained at sufficient boron (B) condition, a down-regulation of the floral genes VvBOR3 and VvBOR4 together with a reduction of floral B content in GA-treated plants was established. These results suggest that impairment in B mobility to reproductive tissues and restriction of pollen tube growth could be involved in the GA-induced parthenocarpy.     

Involvement of Indole-3-Acetic Acid Metabolism in the Early Fruit Development of the Parthenocarpic Tomato Cultivar,MPK-1

Journal of Plant Growth Regulation - Parthenocarpy, or fruit set and growth without fertilization, is a desirable trait in tomato cultivation as it reduces the cost of tomato production. MPK-1 is a...     

Expression of the le Mutation in Young Ovaries of Pisum sativum and Its Effect on Fruit Development

The effect of the le mutation on the growth and gibberellin (GA) content of developing fruits was investigated using the near-isogenic lines of Pisum sativum L. 205+ (LeLe) and 205- (lele). Although stem elongation is known to be reduced in 205- plants by approximately 65%, the growth of pods and seeds was unaffected by the le mutation. GA1, GA3, and GA20 stimulated parthenocarpic development of unpollinated ovaries on both 205+ and 205- plants. GA20 was less active on 205- ovaries than on 205+, whereas GA1 had similar, high activity in both lines. The activity of GA3 was even higher than that of GA1 in both lines. Decapitation of 205+ plants induced parthenocarpic development of unpollinated ovaries, but this treatment was much less effective on 205- plants. The contents of GA1 and GA8 in entire ovaries 6 d after anthesis, as well as in the pod and fertilized ovules, were substantially lower in 205- than in 205+ plants, whereas the reverse was true for the levels of GA20 and GA29. These results suggest that 3[beta]-hydroxylation of GA20 to GA1 is reduced in ovaries as well as in vegetative tissues. Thus, the le mutation appears to be expressed in young reproductive organs of the 205- line, even though it does not affect the fruit phenotype. Because the content of GA3 in the ovary was similar in the two lines, one explanation for the normal fruit size in the 205- line is that GA3 is the native regulator of pod growth. Alternatively, sufficient GA1 may still be produced in 205- fruits to maintain normal pod growth.     

黄瓜白色果皮基因遗传规律及定位研究

以黄瓜嫩果深绿色果皮自交系1507(P1)和白色果皮自交系1508(P2)为亲本,构建6世代遗传群体(P1、P2、F1、F2、BC1P1、BC1P2),对黄瓜嫩果白色果皮基因(w)进行遗传规律分析和基因定位研究。结果表明,黄瓜白色果皮性状由隐性单基因(w)控制,深绿色对白色为显性。利用F2群体,结合分离群体分组分析法筛选得到了14个与w基因相关的SSR标记,构建了该基因的SSR连锁群,将其定位到黄瓜3号染色体上,两侧的标记为SSR23517和SSR23141,遗传距离分别为4.9cM和1.9cM。侧翼标记之间的物理距离为1 150kb,在该区域中共预测了500个候选基因。该研究对w基因的初步定位,为该基因精细定位及分子标记辅助选择育种奠定了良好的基础。     

alpha-l-Arabinofuranosidase from Radish (Raphanus sativus L.) Seeds

An α-l-arabinofuranosidase has been purified 1043-fold from radish (Raphanus sativus L.) seeds. The purified enzyme was a homogeneous glycoprotein consisting of a single polypeptide with an apparent molecular weight of 64,000 and an isoelectric point value of 4.7, as evidenced by denaturing gel electrophoresis and reversed-phase or size-exclusion high-performance liquid chromatography and isoelectric focusing. The enzyme characteristically catalyzes the hydrolysis of p-nitrophenyl α-l-arabinofuranoside and p-nitrophenyl β-d-xylopyranoside in a constant ratio (3:1) of the initial velocities at pH 4.5, whereas the corresponding α-l-arabinopyranoside and β-d-xylofuranoside are unsusceptible. The following evidence was provided to support that a single enzyme with one catalytic site was responsible for the specificity: (a) high purity of the enzyme preparation, (b) an invariable ratio of the activities toward the two substrates throughout the purification steps, (c) a parallelism of the activities in activation with bovine serum albumin and in heat inactivation of the enzyme as well as in the inhibition with heavy metal ions and sugars such as Hg²⁺, Ag⁺, l-arabino-(1→4)-lactone, and d-xylose, and (d) results of the mixed substrate kinetic analysis using the two substrates. The enzyme was shown to split off α-l-arabinofuranosyl residues in sugar beet arabinan, soybean arabinan-4-galactan, and radish seed and leaf arabinogalactan proteins. Arabinose and xylose were released by the action of the enzyme on oat-spelt xylan. Synergistic action of α-l-arabinofuranosidase and β-d-galactosidase on radish seed arabinogalactan protein resulted in the extensive degradation of the carbohydrate moiety.     

嫁接的西瓜果实发育过程中叶和果实蔗糖代谢的一些特性

嫁接瓜果实发育过程中,叶内蔗糖含量和干物质积累显著高于自根瓜,自根瓜和嫁接瓜的叶中蔗糖含量与酸性转化酶（AI）、蔗糖磷酸合酶（SPS）活性均呈显著正相关;嫁接瓜果实中蔗糖含量显著低于自根瓜,SPS活性和果实中糖分的跨液泡膜运输能力亦较自根瓜低;自根瓜和嫁接瓜叶的干物质积累与叶中AI和SPS活性、果实AI活性呈显著负相关,与液泡膜H^＋-ATPase活性呈显著正相关。     

CPPU对瓠瓜单性结实的诱导作用及对细胞分裂和内源激素水平的影响

NAA和GA3处理未经授粉的瓠瓜子房不能显著促进其细胞分裂和膨大而产生单性结实果,而CP-PU处理未经授粉的瓠瓜子房则使其细胞数目和中果皮单个细胞横切面积以及单果重都显著高于未授粉和人工授粉果.经CPPU诱导座果而产生的单性结实果中IAA、ABA和t-zeatin的浓度均不同程度地低于人工授粉和不授粉果实.     

Hungermodifikationen beiRapbanus sativus L.

Ohne ZusammenfassungMit 4 AbbildungenFrau Prof. Dr.E. Schiemann zum 80. Geburtstag gewidmet.