濒危植物血皮槭花部特征和交配系统

【目的】探究我国特有濒危植物血皮槭花部特征和交配系统类型对有性生殖过程的影响,寻找可能导致其结实率低的原因,为缓解当前苗木供需矛盾、制定有效措施奠定理论基础。【方法】以血皮槭植人工栽培植株为材料,通过物候观测、花形态特征测量、异交指数和花粉-胚珠比估算、花粉生活力和柱头可授性检测和人工授粉研究对象套袋试验等方法,对血皮槭的开花动态、花部特征和交配系统进行研究。【结果】1)血皮槭花性别表达复杂,花基于功能可分为雄花和雌花2类;其中雄花根据雌蕊退化程度又分为雄花Ⅰ型和雄花Ⅱ型。雄花Ⅰ型仅具有雄蕊,雄花Ⅱ型具有雄蕊和退化雌蕊,雄蕊长于雌蕊,二者皆不具子房,功能均表现为雄性。雄花Ⅰ型和Ⅱ型大小无差别,Ⅰ型较常见,Ⅱ型较少见。雌花为假两性花,柱头高于花药,花柱具卷曲现象,花开放过程中花药始终不开裂散粉,为功能雌性。2)血皮槭单花经历花蕾期、萌动期、露白期、开放期、凋零期5个阶段,雄花从开放到脱落平均耗时7.6天,雌花从开放到坐果(花期结束)平均耗时11.6天。常3小花组成1个聚伞花序,由雄花和雌花组成的混合类型花序中,通常表现为雌花先熟。3)血皮槭每年开花1次,花期4月,开花历时19.5天左右。...     

提高认识 多措并举 积极推进北京市杨柳飞絮治理工作

正一、北京市园林绿化杨柳树基本情况杨树和柳树为雌雄异株植物,分为雌株与雄株,它们的花为单性花,葇荑花序。当春天杨树还没有长出嫩叶时,雄株上的雄花先开放,经过一段时间发育成熟后,雄花序上的花药自然裂开,花粉飞散而出,进行传粉,然后雄花序逐渐萎蔫脱落,春天在一些杨树的下面看到的像毛毛虫似的那些东西就是杨树的雄花序。比雄花稍晚一些,雌株上的雌花开始开放,伴随着雌花序的发育成熟,雌树上鲜嫩的幼叶也开始慢慢地长出来。雌花序是由若干朵小花组成穗状的葇荑花序,每一朵小花发育后长     

薄壳山核桃不同无性系开花物候特性观测和比较

对薄壳山核桃32个无性系的雌、雄花开花物候期和花量进行了观测和比较。结果表明:2011——2014年薄壳山核桃无性系开花物候期有所差异,但开花物候类型一致。2013年,供试的32个薄壳山核桃无性系整个花期持续时间为4月24日——5月21日。雄花花期持续时间为11 18 d,雌花花期持续时间为9 17 d;雌花最佳授粉期与雄花散粉盛期持续天数均为3 8 d。依据雌花与雄花开放的先后次序可以确定其中的16个无性系为雌先型,10个无性系为雄先型,6个无性系为同时型;并根据观测结果确定了其中86个可行的授粉组合。最佳的授粉配置方案为:将1号、5号、27号、29号、35号无性系作为马汉、28号、65号无性系的授粉配置无性系。32个薄壳山核桃无性系之间,雄花序长度无显著性差异,单枝雄花簇数、单个雄花序花粉囊数、单株雄花序总数、单枝雌花数、每簇雄花序数、单株雌花总数的差异均达到显著水平,总体变异幅度最大的是单株雄花序总数(变异系数为75.51%)。     

植物生长调节剂对板栗生长、性别分化和结蓬的影响

板栗(CastaneamollissimaBlume)原产我国,是重要的经济林树种。板栗普遍雄花多、雌花少,雌雄花比例常为1∶2000～4000,这是造成产量低的主要原因[1],因此,促进雌花分化,减少雄花数量对提高板栗产量具有重要意义。板栗花芽分化的特点与苹果(Malusspp.)、梨(Pyrusspp.)不同,板栗在芽内只进行雄花序原基的分化,而雌花簇和所有花器官分化形成都是在芽外完成的。李中涛等[2]认为在母枝大芽内形成雏梢(即是来年新梢),并分化形成全部雄花序原基,而其上的两性花序要在来年春季发芽后形成。板栗混合花芽的分化具有可塑性,易受外源激素和外界条件等…     

白桦雌雄花发育周期的时序特征

以20～30年生白桦的雌雄花序为材料,研究东北地区白桦花发育的生殖周期和发育时序特征.结果表明:雌花序出现于4月中下旬,5～10 d后开始受粉,持续1周左右; 大孢子母细胞于5月中旬开始减数分裂,3～4 d后形成大孢子,功能大孢子继续发育,成熟胚囊在5月底产生,并进行受精,6月初开始胚胎发育,8月中下旬种子成熟.雄花序出现于5月底,比雌花序晚1个月左右; 小孢子母细胞于7月中旬开始减数分裂,8月中旬结束,历时近1个月; 白桦的雄配子体发育很特殊,在当年不形成成熟的雄配子体,以单核小孢子状态宿存于雄花序中越冬,直到第2年4月中下旬才发育成熟,形成具有2核或3核的成熟花粉,随即散粉.雌花受粉时的花粉来源于前1年出现、宿存越冬、第2年4月底开始散粉的雄花.通过比较,建立东北地区白桦雌雄花生殖周期时序特征表,并对白桦雌雄花发育的时序特点进行讨论.     

杨树雌雄同株的花在花序上着生的特点

近年来,我们在物候观察,形态描述,采集种条、采种育种的过程中,发现了欧洲黑杨、密叶杨、欧洲山杨、合作杨、跃×俄杨雌雄同株,现将其形态特征分述如下。 欧洲黑杨:树冠顶部的花序多为雌花序,雄花序、雌雄同花序极少;树冠中部有雌花序,雄花序、雌雄同花序较多,同花序上部是雄花,下部是雌花,或者相反,也有     

罗田板栗主要品种开花结果习性观察

本文调查了罗田板栗主要品种雌雄花序形成状况,雌花序着生部位、不同品种雄花序长度及其上的花簇数,观察了开花和落果物候期及其结果习性。发现:罗田板栗一些栽培品种雌雄花开放时间主要集中在5月下旬至6月上旬,并且存在雌花较雄花早开1-2天的现象;落果主要发生在7月上、中旬以前的一段时间,7月中旬以后落果较轻;板栗雌花不经授粉受精,同异花授粉或自花授粉一样可以“座果”,但所结果球全为空苞。     

板栗、核桃去雄花芽增产新技术

板栗、核桃疏雄可增产25－45％。板栗、核桃树每平方米树冠投影面积平均有雄花序约240－280个，每个雄花序有雄花450－490个。雌花序与雄花序之比为1：14－17，雌花与雄花之比为1：25％一297人据测定，一个核桃雄花芽从萌动开始到成熟，平均每天蒸腾量为1．58士（011）克，花期大约IS天，总蒸腾量23．7克。一个成熟的核桃雄花序比雄花芽多含水3．5克，如不去雄一个，雄花将消耗27．2克水分。一株18年生核桃树的雄花芽将消耗54．4公斤水，一个同于核桃雄花芽重0．036克，一个同干的成熟核桃雄花序重0．660克，比雄花芽增重0．624克。去雄所…     

板栗的花果管理

<正>板栗花芽分化时间长,落蓬与空蓬现象严重,为了实现板栗丰产稳产,获取最大的经济效益,应该以促花为基础、保果为重点,适期合理采收为保障,加强管理,提高果品产量和质量。1改善雌花分化和形成条件,促进雌花分化板栗的雌花序是春季萌芽期在原有雄花序的芽体内形成的。很多栗农一是错误认为板栗雌     

球根秋海棠的栽培技术

1形态特征及习性 球根海棠别名茶花海棠。学名Begonia tuberhybrida Voss（B．tubersa Hort）。多年生草本,块茎肉质,呈不规则的扁球形、有毛。叶互生,多偏心脏状、卵形、先端渐尖。花梗腋生,花雌雄同株,雄花大而美丽。雌花小型5瓣,雄花具单瓣、半重瓣和重瓣,颜色丰富,花期夏秋。     

三种观赏海棠花芽分化进程的形态解剖特征

采用常规石蜡切片法,对原产于我国的垂丝海棠和引自北美的观赏海棠‘印第安魔力’、‘春雪’花芽分化的形态发育进程进行观察分析。结果表明:垂丝海棠花芽形态分化始于7月中上旬,分化进程可划分为6个阶段:花芽分化前期、花序原基分化期、萼片原基分化期、花瓣原基分化期、雄蕊原基分化期、雌蕊原基分化期,同朵小花各轮原基发育顺序严格,各分化期时间上存在重叠现象。初步判断垂丝海棠营养芽向花芽转变的生理分化期发生在6月上旬至7月中上旬之间,持续时间短于42天。物候观察和切片观察的结果表明垂丝海棠花序类型更偏向于伞形花序而非伞房花序。‘印第安魔力’的花序原基分化期约比‘春雪’晚1个月,这可能是导致‘印第安魔力’的花期相对于‘春雪’较滞后的原因之一。     

控制过量生长对板栗开花结果影响的试验研究

采用疏芽、疏雄花、环剥倒贴皮等技术措施进行对比试验,结果表明:疏芽树比不疏芽的平均每一结果母枝抽生结果枝多0.6条,每一结果枝平均混合花序增加18.1%,每一混合花序上雌花簇增加8.6%;疏雄花比不疏雄花每667?平均产量提高27.4%;环剥倒贴皮比对照第2年每一结果母枝抽生结果枝多33.0%,每一结果母枝产量提高40.0%。     

三台核桃的芽生物学特性观察

本文对三台核桃进行动态和定态观测，结果表明：牙于3月下旬开始分化，先后顺序是叶芽、雄花芽、混合芽；品种不同，顶（侧牙的抽生情况不同，其中结果母枝粗是影响顶（侧）芽抽生数的主要性状；雄花芽的抽生数大于混合芽的抽生数，雄花序开放至脱落历时16d左右。     

砀山酥梨花芽分化及开花物候期观察研究

为确定砀山酥梨花芽分化时期,了解其开花过程,试验以砀山酥梨短枝顶芽为试材,采取田间摘叶法,统计花芽的生理分化时期;通过徒手切片、利用OlympusBX51显微镜拍摄记录花芽形态分化不同阶段的纵切面图片。结果表明,砀山酥梨花芽的生理分化始于6月初,持续到7月中下旬;花芽形态分化始期发生在7月下旬,9月中旬为雄蕊出现期,雌蕊出现期在10月中下旬。次年3月下旬,花芽开始膨大,经历花序伸长、花序分离、白蕾期、大蕾期、初花期、盛花期、末花期和谢花期,4月中旬,开花物候期结束。试验结果为促进砀山酥梨花芽分化、提高果实产量与品质,于花期采取适当的栽培管理措施,提供了理论依据。     

Effect of GA(4 + 7) on the initiation and development of the inflorescence bud of evergreen azalea

Apical buds of evergreen azalea (Rhododendron sp.) were treated with GA(4 + 7) at different stages of development. Treatment of vegetative buds stimulated shoot growth, slightly delayed both flower initiation and development, but increased the number of flower primordia. Treatment at the time of floral transition induced bud abortion at an early stage of the reproductive development. Treatment of inflorescence buds which contained at least one complete flower substituted for chilling in overcoming dormancy and prevented inflorescence bud abortion.     

光皮树花芽分化与内源激素含量的关系

以4年生光皮树嫁接苗为材料,在研究花芽分化过程中解剖学特征的基础上,测定同品系、同龄的光皮树叶内生长素(IAA)、赤霉素(GA3)、玉米核苷素(ZR)、脱落酸(ABA)等4种内源激素含量的动态变化,研究其成花过程中叶片内源激素含量的变化与成花的关系。结果表明:光皮树花芽分化过程可划分为5个时期:花芽未分化期、花序分化期、花萼分化期、花瓣分化期和雌、雄蕊分化期,其中花序分化期还可分为分化前期和分化后期;在花芽分化阶段,IAA、GA3含量保持稳定的相对较低水平,ABA含量高且变化幅度较大,ZR含量相对较低,但随着花的形成含量逐渐升高;高水平的ABA/IAA有利于花芽的形态分化,低水平的ZR/GA3有利于花芽孕育。4种内源激素含量的动态变化均影响光皮树的成花过程。     

Seasonal carbohydrate storage and mobilization in bearing and non-bearing pistachio (Pistacia vera) trees

We analyzed annual carbohydrate storage and mobilization of bearing ("on") and non-bearing ("off") 'Kerman' pistachio (Pistacia vera L.) trees growing on three different rootstocks. On all rootstocks, carbohydrate storage in shoots and branches of "on" and "off" trees was lowest following the spring growth flush. In "off" trees, stored carbohydrates increased and remained high after the initial growth flush. In "on" trees, stem carbohydrates increased temporarily in early summer, but were mobilized in mid-season during kernel fill, and then increased again after nut harvest. During the dormant season, the only substantial differences in carbohydrate storage between previously "on" and "off" trees were found in the roots of the weakest rootstock. The annual carbohydrate storage and mobilization pattern in canopy branches of heavily cropped pistachio trees appeared to be driven by carbohydrate demands related to nut development and untempered by tree vigor. Mobilization of carbohydrates from current-season and 1- and 2-year-old stem wood of "on" trees during the primary period of kernel fill corresponded with the period of inflorescence bud abscission. Thus, the alternate bearing pattern associated with inflorescence bud abscission in 'Kerman' pistachio may be a function of mid-season mobilization of stored carbohydrates in current-season stems resulting in stimulation of inflorescence bud abscission.     

Inhibition of flower bud formation inBetula platyphylla andBetula pendula by gibberellin (GA3) application

Birch (Betula) trees produce a large amount of pollen, which is a cause of serious pollinosis. To control the pollen scattering, we examined the inhibitory effect of gibberellin (GA₃) on flower bud formation of birch. Field-grown trees ofBetula pendula, nine years of age, were treated with a foliar spray of GA₃ (1, 10, and 100 mg L⁻¹),Betula platyphylla trees, 17–23 years of age, were treated with a stem injection of GA₃ (5, 50, and 500 mg per plant) in June or July, 1998. Male flower buds were not observed at the top of new shoots in June, but were observed in July. The number of inflorescence that emerged from randomly sampled branches was counted the next spring. The foliar spray of GA₃ in June at the dose of 10 or 100 mg L⁻¹ decreased the number of inflorescence. Stem injection in June at a dose higher than 50 mg per plant completely inhibited flower bud formation, although it increased bud mortality in some trees. The most effective dose of GA₃ for stem injection to inhibit flower bud formation was between 0.04 and 0.44 mg per cm² of stem cross-section area at breast height. These results indicate that GA₃ applied during the period of floral differentiation markedly inhibits flower bud formation in birch.     

万寿菊的组织培养和瓶苗开花研究

对矮生杂交万寿菊组织培养研究表明：带1个腋芽的无菌苗茎段在MS＋0．05mg／LNAA＋0.2mg／LBA培养基上35d均可诱导出芽,芽诱导率达100％;继代培养时,MS＋0．1mg／LBA是万寿菊较适宜的增殖培养基,平均增殖系数可达10．7,生根率为100％。将带有2个腋芽和1个顶芽的茎段接种到MS＋0.05mg／LBA＋0.4mg／LPP。培养基上,20d后,就能长成1株有根、茎、叶和花蕾、花朵的完整植株。     

Time and method of floral initiation and effect of paclobutrazol on flower and fruit development in Shorea stenoptera (Dipterocarpaceae)

Small Shorea stenoptera Burck. (Dipterocarpaceae) trees of reproductive age growing in an arboretum in west Java were studied to determine the pattern of vegetative shoot development, the time and method of floral initiation and the effect of paclobutrazol on floral enhancement. Vegetative buds were enclosed by two stipules between which was a leaf primordium, a small axillary vegetative bud and another pair of stipules. This sequence was reiterated five to seven times before the vegetative apex was visible. At the time of floral initiation, axillary buds developed into floral spikes and compound inflorescences formed at the end of drooping branches. A compound inflorescence might bear many floral spikes and each floral spike bore many flowers. The compound inflorescence was a modification of the reiterative developmental pattern observed in vegetative shoots. The time of floral initiation began in late June or early July and continued until about November. Floral enhancement using paclobutrazol as a soil drench was attempted in mid-July, but this was later found to be after the onset of floral initiation, and the treatment failed to enhance flowering; however, it appeared to enhance the rate of floral and fruit development. The similarity in vegetative bud development among dipterocarp genera suggests that the time of floral initiation may be easily determined in many species based on simple dissection techniques.