首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 203 毫秒
1.
白菜型春油菜角果和种子性状研究   总被引:1,自引:0,他引:1  
29份白菜型春油菜品种的研究结果表明,角果长度以中长型和短角型品种为主;角果宽度以中宽型和细角型品种为主。长角型角果(长度≥5.81cm)和中宽度角果(直径0.43~0.47cm)品种的每角粒数多,单株产量高。角果长度与角果面积、千粒重和单株产量呈极显著正相关,与每角粒数呈显著正相关,与座果密度呈显著负相关。角果宽度仅与角果面积呈极显著正相关,与其它性状相关皆不显著。  相似文献   

2.
研究了花生属中花生组与拟直立型组35 个种间杂交组合的杂种胚珠和幼胚的发育状况,其中23 个组合为栽培种(2n= 4x)×拟直立型组野生种(2n= 2x),12 个组合为花生组野生种(2n= 2x)与拟直立型组野生种杂交。所有组合的杂种均在发育过程的某一阶段发生败育,但组合间差异较大,野生种之间杂种胚的发育状况一般好于栽培种与野生种的杂种胚,共观察到3 种不同的败育类型。采用胚珠和幼胚离体培养方法,成功地克服了种间杂交不亲和性,在9 个杂交组合中首次获得杂种一代幼苗,移栽后有5 个组合的杂种植株存活下来,并相继开花。对这些杂种后代的花粉育性、结实性、形态特征及花粉母细胞分裂过程进行了全面分析,证实了杂种的真实性。杂种胚珠和幼胚离体培养的成功,为进一步拓宽远缘杂交的亲本范围和更好地利用宝贵的野生花生资源,提供了有效的技术途径。  相似文献   

3.
以同源四倍体多胚苗突变水稻IR36 双为材料,利用激光扫描共聚焦显微镜技术对其双受精过程及胚、胚乳的早期发育特征进行了观察。在“IR36 双”双受精及胚胎发育过程中,观察到一些异常受精现象和胚囊发生败育的异常类型。统计结果表明,异常受精作用或败育胚囊的发生频率高达46.67%,远高于其野生型品种IR36 4x(33.00%)。主要有子房退化、胚囊退化、单受精、双胚珠、双胚等几种异常类型。这些异常类型是导致结实率降低及形成双胚苗的细胞学基础。  相似文献   

4.
2001-2010年国家审定冬油菜品种的产量与主要性状分析   总被引:5,自引:0,他引:5  
对2001—2010年间全国审定的205份冬油菜品种按十五和十一五两个时期,进行产量性状、品质性状与农艺性状统计和对比分析,并对14个性状与产量之间的关系进行相关分析和通径分析。调查品种的各个性状发现:种子产量由十五期间平均2 388.78kg/hm2增加到十一五期间2 670.13kg/hm2,增幅达11.12%,单株角果数、每角粒数和千粒重3个产量因子的增幅分别为4.03%、0.36%和7.10%,表明单株角果数和千粒重的增加是油菜产量提高的主要原因。相关性分析发现,十五期间油菜产量与每角粒数、分枝数、增产点率和生育期呈显著或极显著正相关,另外,十一五期间油菜产量还与单株角果数(r=0.38)达到极显著正相关。通径分析发现,十五期间对产量的直接作用较强的性状分别为:菌核病病株率、菌核病指数、病毒病指数、病毒病病株率、每角粒数和单株角果数。十一五期间对产量的直接作用较高的性状分别为:每角粒数、菌核病病株率、株高、生育期、单株角果数和千粒重。  相似文献   

5.
油菜结实特性与库源关系的研究   总被引:6,自引:8,他引:6  
以4个油菜品种的结实特性研究表明,开花后20d内油菜角果体积和表面积急剧增长,角果和籽粒干重随成熟进程而增加,籽粒干重在开花25d后增重加热,40d左右超过果皮干重。具有生殖生长优势品种的单位角果皮面积的生产力(PPA)和单位角果皮表面积负担的籽粒数(SNPA)较高。果皮与种子的生理代谢进程不同,二者的全氮,叶绿素以及可溶性糖含量的动态变化与角果形态及干物质积累转化进程有明显的相关性。初花期去叶处理可使4个品种明显减产,去叶对分枝产量的影响大于主花序,主要减少分枝的每角粒数;去短叶的减产幅度大于去无柄叶。  相似文献   

6.
采用石蜡切片、杂交和回交技术研究了芥菜型油菜多室材料J163角果的形态特征、单株产量性状构成和遗传控制机制。结果表明,J163的角果由4心皮发育而来,4个果瓣包围种子,2个假隔膜平行,将角果分隔成3个腔室;假隔膜发育稳定,无假隔膜发育障碍或中途退化而形成多室与两室角果嵌合现象;尽管多室材料的千粒重和单株有效角果数均小于两室材料,但多室材料每角粒数和单株产量显著提高,说明多室性状(每角粒数多)有利于提高油菜产量;J163多室性状受隐性核基因控制,无细胞质效应,J163和两室材料J248间在多室位点上存在2对基因差异,但J163的多室性状基因是否为2对独立隐性基因还需进一步研究。根据上述特点可认为J163是新型芥菜型油菜多室材料。  相似文献   

7.
芥菜型油菜与甘蓝型油菜种间杂种二代分离观察   总被引:6,自引:1,他引:5  
从芥菜型油菜×甘蓝型油菜种间杂种F1自由授粉获得的F2的叶型、现蕾期、始花期、雄蕊发育、花粉活性和种子育性的分离观察结果表明,芥甘杂种F2超亲分离,产生大量变异类型,可根据花粉可染率和角果长度对F2植株种子育性进行间接选择。  相似文献   

8.
睡莲属(Nymphaea)植物是我国新兴的水生花卉,其中重瓣型睡莲的花态丰满艳丽,一直倍受睡莲爱好者、育种者的喜爱和关注,在水生园林景观中的应用日渐广泛,但在育种的过程中,育种者经常遇到杂交不结实的现象,导致重瓣型睡莲品种难以培育。为探索重瓣睡莲难以结实的原因,以重瓣睡莲中较具代表性的品种‘泰国王’为实验组,以育性较好的品种‘公牛眼’为对照组,利用石蜡切片技术对其授粉后不同时期的子房进行显微结构比较,采用扫描电镜进一步观察样本的柱头和胚珠,通过RNA-seq测序分析发育与败育子房的基因表达差异。结果表明:2个睡莲品种的柱头表面均分布着多细胞单列乳突,细胞间的连接处形成一圈圈凹槽,乳突数量庞大、排列紧密,配合自身的结构能更容易捕获外来的花粉。‘公牛眼’授粉7 d后子房中大部分胚珠发育成红色种子,10 d后子房膨大成果实,种皮由红色转黑色,形成成熟的种子;重瓣睡莲‘泰国王’授粉7 d后无种子形成,子房中有部分胚珠发育,其表皮变为红色,形态特征与‘公牛眼’授粉4 d后的红色胚珠相似,由此推测少量胚珠可能完成了受精,但无法进一步发育,10 d后子房完全败育。显微结构观察可知,授粉7 d后2个品种的胚珠发育产生明显差异,‘公牛眼’的胚珠明显增大,合子开始分裂形成胚,而‘泰国王’胚珠内珠心萎缩,胚珠逐步败育消解,授粉10 d后,‘公牛眼’胚珠的珠被增厚形成种皮,胚开始发育,进一步向种子形态转变。由转录组测序分析可知,差异基因显著富集在光合作用——天线蛋白、光合作用、卟啉和叶绿素代谢、核糖体、淀粉和蔗糖代谢等通路,这些通路可能是影响睡莲子房发育的关键途径,推测‘泰国王’子房败育可能是因为自身光合作用受到抑制,进而影响了蔗糖、淀粉等营养物质的生成。  相似文献   

9.
三种甘蓝型油菜CMS花药发育研究   总被引:2,自引:0,他引:2  
目的]确定三种甘蓝型油菜CMS花药发育败育时期和细胞学特征;比较它们的花粉活力和微粉率。[方法]以细胞质雄性不育系301A、212A与陕2A为材料,保持系中双2号作为对照,采用常规的石蜡组织切片技术,对三种甘蓝型细胞质雄性不育系油菜败育时期和败育特点进行细胞学研究;花粉活力测定用醋酸洋红染色观察法。 [结果] 不育系301A、212A与陕2A败育均发生在孢原细胞时期,在造孢细胞时期不能正常的形成药室,属于无花粉囊败育型;花粉活力分别为:81.7%、95.6%、100%;微粉率分别为:42.8%、42.8%、14.3%.[结论]新发现的细胞质雄性不育材料301A与212A、陕2A花药发育败育时期相同,败育特点相似;不育系301A的花粉活力和212A与陕2A比较起来差异较大、较低;不育系陕2A微粉率最低。  相似文献   

10.
花期低温阴雨对甘蓝型油菜产量和种子含油量的影响   总被引:1,自引:0,他引:1  
对2010年3月2日~11日低温阴雨条件下19个甘蓝型油菜品种有效结角率、每角粒数、千粒重和种子含油量进行了分析。结果表明:(1)开花后低温阴雨导致油菜有效结角率下降(平均为对照的72.81%),每角粒数减少(是对照的57.32%),种子千粒重稍有增加(是对照的119.79%),含油量降低(是对照的95.31%)。(2)开花时低温阴雨导致有效结角率下降(是对照的46.01%),每角粒数减少(是对照的33.11%),千粒重有所增加(是对照的114.67%),含油量降低(是对照的96.71%)。(3)开花时低温阴雨对所有供试品种的有效结角率、每角粒数影响均要大于开花后。(4)花期低温阴雨的影响因品种而异,希望98、中油821等7个品种抗耐性好。同一品种对开花期和开花后低温阴雨的抗耐性基本一致。  相似文献   

11.
Causes of low seed set in white clover (Trifolium repens L.)   总被引:1,自引:0,他引:1  
A field experiment was conducted to clarify the factors responsible for poor seed set in four white clover ( Trifolium repens L.) cultivars. Although the mean number of ovules per floret was 5·18–5·29, the average number of seeds per floret was found to be only 1·23-1·82. A stainclearing technique was used to examine the cytoplasmic state of the embryo sac in intact, unfertilized, mature ovules and it was found that 28–33% of ovules per carpel were sterile. The abortion rate of fertilized ovules and immature seeds (7 days after pollination) ranged between 32 and 34%. Beyond this period, it was observed that only a very small proportion of the total seeds were lost. The observation of high pollen fertility and a high pollen load strongly suggests that poor pollination does not account for the reduced number of seeds per floret. A 'nutrient competition' hypothesis was proposed for high ovule sterility and post-fertilization abortion of developing seeds.  相似文献   

12.
The number of pods per plant and the number of seeds per pod are the most variable yield components in winter oilseed rape (WOSR). Both the number of ovules per pod and the potential for the ovule to develop into a mature seed may depend on pod position in the plant architecture and time of appearance. The complex developmental pattern of WOSR makes it difficult to analyse. The objectives of this study were to investigate the variability of the following yield components (a) ovules/pod, (b) seeds/pod, and (c) pods/axis in relation to two explanatory variables. These two variables include (1) flower and inflorescence position and (2) time of pod appearance, linked to the effect of assimilate availability.Field experiments were conducted with the variety Mendel. Different trophic states were created by clipping the main stem or ramifications. The number and position of flowers that bloomed within the inflorescence were recorded based on observations every two to three days throughout the flowering season.On the control plants, for the main stem we observed that the number of ovules per pod decreased for a few ranks and then tended to increase and again to decrease at the end. On ramification R1 and R4, the number of ovules increased at first, and then remained constant with the pod rank. Furthermore, the number of ovules per pod remained constant along the inflorescence on the other ramifications and increased with ramifications from top to bottom. The number of seeds per pod did not vary with the pod rank at the basal positions on inflorescences and decreased afterwards along the inflorescence. The clipping of the main stem or ramifications increased the number of ovules per pod, seeds per pod and pods per axis. The number of ovules and seeds per pod did not vary with the time of pod appearance for the pods located at normalised rank 0.01-0.1. However, the number of ovules and seeds per pod can be impacted by the time of pod appearance on the plant scale. Thus, our results indicate that the amount of available assimilates was the primary determinant of pod and seed production during the flowering period. The distribution of resources was significantly affected by both the positions of pods within an inflorescence and the position of inflorescences within a plant.  相似文献   

13.
水稻花粉萌发及花粉管生长动态   总被引:3,自引:0,他引:3  
用显微镜观察水稻花粉粒的萌发、花粉管在雌蕊中的生长以及授粉后不同时间剪除柱头处理对颖花结实率的影响。 水稻花粉粒在授粉2 min后开始萌发;5~10 min后花粉管穿过柱头进入花柱生长;约经30 min花粉管顶端到达子房基部;40 min时有些花粉管顶端可接近胚囊,此时花粉管内胼胝质形成,但数量较少;50 min后花粉管内胼胝质塞大量形成,花粉粒萎缩干瘪。水稻花粉管在柱头、花柱和子房中的生长速率分别为1500、5000、5400 μm/h。水稻授粉后10~15 min剪除柱头的处理只有极少量颖花结实,授粉后20~50 min剪除柱头处理的颖花结实率随处理时间推迟而升高,授粉后50 min剪除柱头处理的结实率达60%以上,接近正常。  相似文献   

14.
提高不育系的异交结实率是杂交小麦制种产量取得突破的重要途径。为明确小麦AL型雄性不育系的异交结实特性,连续3年测定了2个小麦AL型不育系36A和3235A的柱头活力、柱头外露率、颖间距和自然异交结实率。结果表明,36A和3235A的平均自然异交结实率分别为113.02%和44.65%,柱头活力分别为104.96%和76.7%,差异均达到显著水平;二者的柱头外露率和颖间距无显著差异。相关分析表明,授粉天数与柱头活力呈显著负相关,柱头活力随授粉天数的延长而降低;柱头活力与柱头外露率和颖间距、柱头外露率与颖间距间均呈显著正相关。随授粉进程推移,柱头活力、柱头外露率和颖间距均呈先增后减趋势,36A的3个指标均高于3235A,综合表现为异交结实率高。花后第4~11天套袋饱和授粉异交结实率最高,授粉后第6~12天,柱头外露率和颖间距均达到最大。因此,小麦AL型不育系的恢复系扬花始期比不育系推迟2~3 d,小花陆续开放、柱头活力也较强,并持续开颖,可保持较高结实率,为最佳授粉时间。  相似文献   

15.
比较甘蓝型油菜同一遗传背景组合分离出的黄黑两个品系在种子发育过程中若干特性。结果表明:黄籽比黑籽胚体转绿色快,退化胚珠数少,结籽率高。黄籽油菜种皮转色时期为开花后30天。黄籽种子体积增加比黑籽快5—10天,干物质积累速度在花后35天内显著快于黑籽。黄籽含油率比黑籽高7.97%。  相似文献   

16.
荔枝胚胎败育与胚珠内源激素关系的研究   总被引:14,自引:1,他引:13  
研究了绿荷包(胚胎完全败育品种)和乌叶(胚胎发育正常品种)荔枝胚珠中内源激素和胚胎发育的关系,结果表明:绿荷包胚珠中ABA含量与ABA/(IAA、GA1+3)和ABA/(ZRs+DHZRs+iPAs)比值在胚胎败育发生时期保持较高水平,IAA、GA1+3和CTK含量则在花后 7 d迅速下降,并在败育期处于较低水平。乌叶胚珠中 ABA含量在花后 7 d即急剧下降,其含量与以上2个比值在各个胚胎发育阶段均始终明显低于绿荷包,但前者的IAA、GA1+3和CTK含量在胚胎发育早期则远高于后者,其中尤以CTK含量差异显著。ZRs、DHZRs和iPAs含量有不同变化特点,对胚胎败育亦有不同影响。   相似文献   

17.
Pollen Grain Germination and Pollen Tube Growth in Pistil of Rice   总被引:1,自引:0,他引:1  
The germination of pollen grain in vitro and the growth of pollen tube in the pistil of rice were observed with a microscope. The stigma was removed at different time points after pollination to study its effect on seed setting rate. The rice pollen grain started to germinate at 2 min after pollination and the pollen tube penetrated stigma into style in 5–10 min, 30 min later the end of pollen tube reached the bottom of ovary, and only some pollen tubes arrived at embryo sac at 40 min after pollination. Mea...  相似文献   

18.
为明确小麦光温敏核雄性不育系的开颖、柱头外露特征及其异交结实能力,在小区制种条件下考察了4个不育系的开颖、柱头外露小花数和异交结实粒数,并分析了开颖率、柱头外露率与异交结实率的关系。结果表明,供试不育系的开颖率为18.10%~86.28%、柱头外露率为28.68%~67.33%,其中BS366为高开颖率低柱头外露率类型,BS206为中开颖率高柱头外露率类型,BS212为低开颖率中柱头外露率类型,BS1453为低开颖率低柱头外露率类型。供试不育系柱头外露小花和开颖小花的异交结实率分别为 59.39%~65.62%和26.16%~55.54%,二者平均异交结实率相差23.46个百分点,表明柱头外露小花异交结实能力高于开颖小花,且不育系间的差异较小。供试不育系的异交结实率在23.58%~53.16%之间,各不育系间差异显著;开颖小花异交结实粒数占总异交结实粒数的平均比例为50.55%,柱头外露小花异交结实粒数占总异交结实粒数的平均比例为68.47%。开颖率、柱头外露率与异交结实率呈极显著正相关,相关系数分别为0.719和0.372,开颖率与柱头外露率也呈极显著正相关(r=0.467)。因此,高开颖率或高柱头外露率的不育系均可获得较高的异交结实率,但柱头外露率较高的不育系异交结实率也较为稳定。在育种实践中,应首先注重选择不育系的开颖率,其次加强柱头外露性状选择,以便有效而稳定地提高异交结实率。  相似文献   

19.
Chilling temperatures at flowering cause floral abortion in most chickpea cultivars. Recent evaluations of germplasm showed distinct genotypic differences in pod and seed set at low temperature but the morpho-physiological basis for such variation is unclear. Observations in the field during cold spells of December and January, and at 15/5°C and 15/0°C (day/night) regimes in growth rooms showed distinct genetic variation in flower morphology, gamete development (viability and size of pollen and ovules) and function (pollen germination and tube growth, ovule viability and fertilization, etc.). The greater pod-setting ability of tolerant lines (ICCVs 88502 and 88503) than the sensitive cultivars (Annigeri, Pant G 114, etc.) was associated with a higher pollen vigour (germination and tube growth) and ovule viability at low temperature in the former. The number of ovules was not affected by cold stress in all cultivars/lines but pollen size and viability were reduced in Annigeri. The reduced ovule fertilization, associated with decline in pollen tube growth and ovule viability, was the major cause for poor seed set at low temperatures. The magnitude of effects on gamete function varied with cultivar/line and severity of stress. Function of both pollen and ovules was adversely affected in Annigeri in 15/5° and 15/0°C regimes. In contrast, the reduction in pollen vigour was more than in ovule viability in ICCV 88510 and Pant G 114 at 15/5°C. At 15/0°C, however, both pollen vigour and ovule viability were reduced. A small increase in pod set of sensitive genotypes from manual pollinations with pollen from plants in the warm regime further suggested that pollen function was more adversely affected than pistil function at moderately low temperatures.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号