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1.
《广西植物》2017,(12)
该研究运用酶联免疫法(ELISA)对不同成花量(花多、花少、无花)金花茶花果期果枝叶内源激素吲哚乙酸(IAA)、赤霉素(GA_3)、玉米素核苷(ZR)、脱落酸(ABA)含量进行了测定。结果表明:始花期金花茶果枝叶内源IAA先升高后降低,花多株含量低于花少株;有花株ZR含量高于无花株;GA_3含量呈现整体上升趋势,有花株高于无花株;ABA含量先降低后升高,无花株高于花多株。盛花期IAA、GA_3、ABA含量整体下降,ZR含量先降低后升高,花多株叶内源IAA、ZR、GA_3含量高于花少株或无花株,ABA含量低于花少株或无花株。花期内,有花株果枝叶IAA/ZR、IAA/ABA、ZR/ABA、GA_3/ABA比值均高于无花株,而(IAA+GA_3)/ZR比值低于无花株,说明金花茶花果的发育不仅和单个激素的含量有关,还和激素平衡有关。秋梢期营养生长旺盛时无花株IAA/ZR比值较大,花果期生殖生长强烈时比值较小,(IAA+GA_3)/ZR与之相反。这说明花蕾期高水平的内源IAA、ZR和ABA及低水平的内源GA_3有利于金花茶开花;末花期高含量的IAA、ZR和低含量的GA_3、ABA可减少落花落果,提高坐果率,有利于果实快速生长;果实生长后期高含量的ABA有利于果实成熟。该研究结果为生产上应用生长调节剂调控金花茶成花、坐果提供了理论依据。 相似文献
2.
为探讨野桐属(Mallotus)雌雄异株的进化和传粉机制,对白背叶(Mallotus apelta)野生居群的性系统和传粉生物学进行了研究。结果表明,所调查的白背叶居群均由雌性(F)、雄性(M)和少数两性(B)个体组成,平均性比为1:0.66:0.18(F:M:B);3种性别植株的基径大小差异不显著;雌株与两性植株的单花胚珠数、单果结籽数和自然结实率无显著差异;雄株与两性植株的花粉萌发率、花粉组织化学和花粉微形态特征也无显著差异,但雄株的单花花粉量是两性植株的1.26~1.63倍,且差异显著;雌株的异交结实率为96.67%,两性植株的异交结实率为76.00%,两者差异显著,说明居群内雌株的潜在种子生产力明显高于两性植株;野外观察到雄株和两性植株上的雄花具有访花者而雌株没有;雌株经套网处理后结实率超过30%而套袋处理不结实。这些表明白背叶具典型的亚雌雄异株性系统,雌株和雄株的适合度均高于两性植株;雌株以风媒传粉结实,两性植株可能兼有风媒和虫媒传粉特征。 相似文献
3.
以雌雄异株植物东北鼠李(Rhamnus schneideri var. manshurica)为研究对象,分析不同繁殖阶段雌雄植株叶片元素含量的性别差异和动态变化,可为雌雄异株植物性别特异性资源需求及利用策略提供理论参考。该研究在吉林蛟河天然针阔混交林内建立1块23.76hm2的永久性固定监测样地,于2019–2021年花期和果期(共5个繁殖阶段)选择样地内一定数量的东北鼠李雌雄植株,测定每株的叶片营养元素(氮、磷、钾、钙、镁、铁、硼)含量,比较东北鼠李雌雄植株在不同繁殖阶段叶片各营养元素含量的差异及动态变化;并计算各个繁殖阶段雌雄植株的花、果生物量,利用方差分析方法检验雌雄植株各个繁殖阶段的花果生物量差异,以分析雌雄植株叶片营养元素出现性别差异及动态变化的背后机制。结果表明:(1)东北鼠李雌雄植株的叶片营养元素含量具有显著的性别差异,但这种性别差异仅在某些繁殖阶段存在。在2019年花期,雌雄植株的各叶片元素含量均无显著差异,2021年花期,雌株叶片的磷含量显著小于雄株。在2019年果期,雌株叶片的磷、钾含量显著小于雄株;而在2020年果期,雌株叶片的氮、磷、钾、钙、镁、铁、硼含量均显... 相似文献
4.
雌雄异株植物资源分配模式上往往表现出显著的性别二态性,但在叶片光合及功能性状上是否有差异目前仍未有定论,且与发育阶段的关系尚不明确。阐明上述问题,能够进一步了解雌雄异株植物的生理生态特征,并为理解性别对性二态植物生长发育的影响机制提供理论依据。以雌雄异株绒毛白蜡(Fraxinus velutina Torr.)为研究对象,针对不同发育阶段不同性别植株进行光合特征及叶功能性状测定,采用双因素方差分析了不同发育阶段下雌雄植株光合能力及叶功能性状的性别间差异,采用Pearson检验了雌雄植株各叶功能性状之间的相关性,并采用标准化主轴分析(Standardized major axis regression, SMA)分析不同性别植株净光合速率与叶功能性状的相关性。结果表明性别和发育阶段显著影响植物个体的光合能力和叶功能性状。总体而言,雄树在坐果期和果实成熟期均表现出更强的净光合速率(Pn)、更高的比叶面积(SLA)、叶绿素含量(Chl)和叶氮含量(LNC);而雌树在果实膨大期表现出更强Pn、SLA和Chl。雌雄性别内Pn与SLA、Chl和LNC间均呈显著正相关(P<0.05),雄树的S... 相似文献
5.
对湖南省浏阳市周洛村桂花峡、福建省长汀县官坊村石峰寨东北坡和南坡、浙江省龙泉市供村及张公桥和毛圩村6个野生桂花〔Osmanthus fragrans(Thunb.)Lour.〕居群中桂花单株的性别比例进行了统计,并对单性雄株和两性株的花部雌蕊形态、花粉粒数量和外部形态及花粉在柱头上的萌发情况进行了观察和比较。结果显示:6个居群中雄性比率差异较大(0~0.62),平均值接近0.5;其中,石峰寨东北坡和南坡居群的雄性比率最大(0.62),张公桥居群的雄性比率最小。两性株花的雌蕊发育正常,而单性雄株的花具有退化雌蕊的痕迹。不同居群及个体间每个花药的花粉粒数量存在一定差异,且单性雄株每个花药的花粉粒数量多于两性株,但差异均不显著(P>0.05)。单性雄株和两性株的花粉粒形态一致,花粉粒均为长椭圆形、极轴长16μm、具三沟和网状雕纹型表面纹饰;花粉均具有较高活力且均能在柱头上萌发。结合对木犀属(Osmanthus Lour.)其他种类的观察结果认为:桂花的繁育系统应属功能性的雄全异株,这种繁育系统可能为两性同体与雌雄异株间的过渡类型,在木犀属的其他种类中也能观察到雄全异株的存在。 相似文献
6.
《应用昆虫学报》2017,(1)
[目的]为探索不同成熟度的苹果、桃、梨果实对梨小食心虫Grapholitha molesta生长发育和繁殖的影响。[方法]在寄主果实不同发育阶段采果,并在室温(26±0.5)℃,L:D=15:9,RH=70%±10%条件下,测定了梨小食心虫在不同成熟度的桃、梨、苹果果实上的发育历期、存活率和繁殖力,并组建了其生命表。[结果]梨小食心虫在不同成熟度的苹果、桃、梨果实上的生长和繁殖有显著差异。幼虫发育历期在幼果期的寄主果实上无显著性差异,果实膨大期和成熟期以桃最短(10.44 d,9.42 d)。总存活率在幼果期和膨大前期、膨大后期为苹果最高(3.47%,13.04%,25.35%),果实成熟期为梨最高(39.70%)。单雌产卵量在幼果期和果实膨大前期为苹果最高(138.33粒/雌,145.33粒/雌),果实膨大后期为桃最高(151.90粒/雌),成熟期为梨最高(182.12粒/雌)。生命表分析结果表明,净生殖率幼果期为苹果最高(8.60),果实膨大期为桃最高(19.42),果实成熟期为梨最高(47.44)。内禀增长率幼果期苹果最高(0.0632),果实膨大前期为桃最高(0.0210),果实膨大后期为桃最高(0.0999)成熟期为梨最高(0.1117)。[结论]幼果期最适宜的寄主为苹果,果实膨大期最适宜寄主为桃,果实成熟期最适宜寄主为梨,这为揭示梨小食心虫在不同寄主间转移为害规律和田间防治提供了科学依据和参考。 相似文献
7.
为探究光照强度减弱对不同发育期的刺梨(Rosa roxburghii Tratt.)果实和叶片中维生素C与糖含量及相关酶活性的影响,以‘贵农5号’刺梨扦插苗为材料,采用遮阳网设置光强减弱20%、40%、60%的3个遮光处理,以自然光照强度为对照(CK),分析不同光照强度条件下刺梨果实和叶片中维生素C含量及相关酶活性以及糖含量的变化。结果表明:(1)光照强度减弱后,不同发育期的刺梨果实和叶片中维生素C含量均显著降低,对照及3个处理间的果实维生素C含量的差异在快速膨大期均达到显著水平。(2)随着光照强度的减弱,刺梨果实和叶片中L 半乳糖 1,4 内酯脱氢酶(GalLDH)、单脱氢抗坏血酸还原酶(MDHAR)和脱氢抗坏血酸还原酶(DHAR)活性均降低,而抗坏血酸氧化酶(AAO)和抗坏血酸过氧化物酶(APX)活性均增强,尤其是果实中MDHAR活性在快速膨大期迅速大幅增强。(3)刺梨果实和叶片中可溶性糖、蔗糖、葡萄糖、果糖含量随光照强度减弱而降低,但果实中葡萄糖含量在快速膨大期增加尤为迅速。(4)果实中维生素C含量与叶片中蔗糖、葡萄糖含量在不同发育期均呈极显著正相关关系,快速膨大期果实中GalLDH、MDHAR活性与维生素C含量呈极显著正相关关系且相关系数均达到最大值,而其APX活性与维生素C含量呈极显著负相关关系且相关系数达到最大值。研究认为,光照强度通过调控刺梨果实中维生素C合成及相关代谢关键酶的活性与叶片中光合产物的含量最终影响果实中维生素C的积累量;弱光环境不利于刺梨果实和叶片中维生素C及糖的积累,其影响在果实快速膨大期尤为明显;良好的光照是保证刺梨果实优良品质的基本条件。 相似文献
8.
以‘金冠’苹果及其优系‘SGP-1’为试材,测定果实发育期间有机酸组分、含量和苹果酸代谢相关酶活性,分析它们的变化规律及相关关系,以探索苹果有机酸积累的关键时期和关键酶,揭示果实低酸成因。结果表明:(1)苹果果实发育期间,‘SGP-1’的有机酸含量显著低于‘金冠’,成熟时仅为‘金冠’的二分之一,且主要由苹果酸、奎宁酸、酒石酸和柠檬酸组成,幼果期以奎宁酸为主,成熟期以苹果酸为主。(2)‘SGP-1’的苹果酸含量显著低于‘金冠’,其在幼果期和膨大期变化规律与‘金冠’相反,且积累关键时期和快速下降期早于‘金冠’;‘SGP-1’果实其余酸组分含量变化趋势与‘金冠’基本一致,但在幼果期显著高于‘金冠’,在成熟期与‘金冠’差异不显著。(3)‘SGP-1’的苹果酸代谢相关酶活性在幼果期均显著高于‘金冠’,成熟期持平或显著低于‘金冠’;幼果期MDH活性和成熟期ME活性在两材料间变化规律相反。(4)‘SGP-1’的幼果期苹果酸积累与PEPC和VHA活性呈极显著正相关关系,而同期‘金冠’则与MDH、PEPC和VHA活性呈极显著负相关关系;‘SGP-1’膨大期苹果酸积累与MDH、PEPC活性呈极显著负相关关系,与PEPCK和VHA活性呈显著正相关关系,而同期‘金冠’则与PEPC、ME和VHP活性呈极显著或显著负相关关系;二者成熟期苹果酸积累均与MDH、PEPC、ME和VHP活性呈极显著或显著负相关关系。研究发现,‘SGP-1’是以苹果酸为主的低酸型‘金冠’苹果变异优系,对苹果酸积累起主要调控作用的酶种类和活性与‘金冠’不同,导致了‘SGP-1’的低酸品质,该研究结果为深入探索果实低酸形成机理和培育高糖低酸新品种奠定了基础。 相似文献
9.
从开花动态、传粉昆虫、花的形态结构、繁育系统、花粉活力和柱头可授性等方面研究了我国特有珍稀植物瘿椒树(Tapiscia sinensis Oliv.)的传粉生物学特性。瘿椒树是典型的雄全异株植物,两性花中含有功能性花粉,且自交亲和,但雄花花粉活力和萌发力是两性花的10倍以上。雄株和两性植株具有相同开花物候期,花期均为5月下旬至6月上旬,单花期为4-5天,雄花和两性花的5枚花药开裂的不同步性明显延长了散粉时间。两性花雌蕊先熟,柱头可授性较长。具有适应风媒和虫媒传粉的花部特征。传粉昆虫主要为蜜蜂科(Apidae)和食蚜蝇科(Syrphidae)昆虫,访花高峰期为8:30-10:30。维持瘿椒树雄全异株的可能机制是:雄株总体上增加了异交花粉的数量和质量;两性花的雄蕊为该物种提供了繁殖保障,同时为传粉者提供了报酬。 相似文献
10.
雄全异株流苏树的花部特征及繁育系统研究 总被引:2,自引:0,他引:2
雄全异株是自然界罕见的繁育系统。通过野外观察和人工授粉实验对雄全异株植物流苏树传粉生物学特征及繁育系统进行研究。结果表明:流苏树的雄花与两性花的雄蕊发育过程基本一致,均能产生功能花粉粒。两性花的两个心皮原基愈合分化形成雌蕊,雄花的两个心皮原基愈合后形成一个空室并停止发育至整体退化。雌蕊先熟,柱头可授期长,花粉在花药开裂后具有活力,室温下,活力维持在10%以上约2周。流苏树靠风和昆虫(主要是蓟马和食蚜蝇)传粉。控制授粉30 d后,自然对照结实率为34.36%;两性花不存在无融合生殖现象,自交亲和,但自发自交的结实率仅10.70%;人工授粉下杂交结实率显著高于自交(同株异花);有性生殖受到传粉者限制;是混合交配系统。证实流苏树是木犀科又一功能性的雄全异株,其依靠雄株增加异交花粉的数量和质量,避免自交衰退;同时两性花的自交亲和保障生殖成功。流苏树雄花的雌蕊退化,从另一个角度证明木犀科的雄全异株是两性株向雌雄异株进化的过渡状态。 相似文献
11.
Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising. 相似文献
12.
T. R. Deason P. C. Silva S. Watanabe G. L. Floyd 《Plant Systematics and Evolution》1991,177(3-4):213-219
Komárek has recently reviewed the various species assigned to the green algal genusNeochloris
Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia.
Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class. 相似文献
13.
The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not. 相似文献
14.
Since 1999, four specific weevils (Coleoptera, Curculionidae) were released in the Republic of Congo against three exotic floating water weeds: Neochetina eichhorniae Warner and N. bruchi Hustache against water hyacinth, Neohydronomus affinis Hustache against water lettuce, and Cyrtobagous salviniae Calder and Sands against water fern. Recoveries of exotic weevils were made from all 24 release sites except one, and all four species have established and spread (up to 800 km for water hyacinth weevils). Within a few years of releases, control of water fern and water lettuce was such that fishing and navigation could be resumed, while reductions of water hyacinth populations were only beginning. 相似文献
15.
The genusKarschia, in the earlier sense, including saprophytes and parasites on lichens, has been thought to be a non-lichenized parallel genus of the lichen genusBuellia. Modern workers included it on the one hand inBuellia, on the other hand combined it with bitunicate ascomycetes. It is now proved thatKarschia is heterogeneous and contains but superficially similar members both of the genusBuellia of theLecanorales and of typical or masked bitunicateAscomycetes. Therefore, it can not be regarded as a link betweenLecanorales andDothideales. The type species ofKarschia belongs to theDothideales.
相似文献
16.
A molecular phylogeny of Hebeloma species from Europe 总被引:2,自引:1,他引:1
Herbert Boyle Bettina Zimdars Carsten Renker Franois Buscot 《Mycological Research》2006,110(4):369-380
In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section. 相似文献
17.
Gary D. Grossman 《Environmental Biology of Fishes》1979,4(3):207-218
Synopsis In a fourteen month study (May 1976 – June 1977) I examined the following characteristics of an intertidal bay goby (Lepidogobius lepidus) in Morro Bay, California, U.S.A.: annual and seasonal patterns of abundance, age composition and growth rates, survivorship
and mortality patterns, and the reproductive cycle for female gobies.
Fishes were collected with the aid of quinaldine and otoliths and ovaries removed. Age and growth rates were estimated from
otolith annuli using a back calculation formula and a Brody-Bertalanffy growth curve. Mortality rates were derived using the
methods of Heincke (1913), Robson & Chapman (1960), mean age, and a catch curve (Ricker 1975). A gonad index was used to describe
the annual reproductive cycle.
Results indicated that abundance fluctuated seasonally and that these fluctuations appeared to be caused by reproductive emigrations.
Bay gobies reached an age of 7+ and a standard length of 87 mm. Growth was relatively constant (6 mm yr−1) until age 5, at which point it began to decline. The mean rates of survivorship, mortality, and instantaneous mortality
were 0.75, 0.25, and 0.29 respectively. Mortality rates for individual age classes ranged from 0.13 to 0.51 and increased
with age. This stock appears to reproduce mainly during the winter. 相似文献
18.
19.
Systematic significance of mature embryo of bamboos 总被引:1,自引:0,他引:1
The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae. 相似文献