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1.
印度学者K.D.Dhiman的研究表明:在阳光或灯光照射下,水稻成熟花药会很快地释放花粉,但这样对授粉多少有点困难和效率偏低。为了提高授粉效率,他采取了一种液体授粉技术。把成熟花药放在烧杯或培养皿内,在太阳下放置15—20分钟,然后加入蒸馏水益使劲摇动,直到溶液变成淡黄色的花粉悬浮液。授粉的方法是:在刚去雄或先天去雄套袋的小花上用注射器注射一滴上述溶液。这种方法的授粉百分率比撒粉到去雄小花的柱头上高2—4倍。 下表是6个品种分别用液体授粉和撒粉授粉各处理1.00个小花的授粉率。水稻液体授粉效果好  相似文献   

2.
不育系柱头和恢复系花粉生活力的观察   总被引:1,自引:1,他引:1  
使用CO2诱导水稻颖花整齐地开放,去除不育系未开颖以及柱头来外露的颖花,授粉于外露柱头,以其结实率来衡量柱头活力;定时将裂药后的花粉散落于马铃薯培养基上,镜检花粉的发芽率。结果表明;不育系颖花外露柱头的生活力能维持3一4天,但以当天和第二天的活性为最高;恢复系开花后残留在花药中的花粉萌发力仍能维持3小时之久。  相似文献   

3.
利用不同液体介质对甘蓝型油菜CMS辅助授粉的研究   总被引:2,自引:0,他引:2  
利用不同浓度的食用蔗糖和食用盐液体介质及制备的介质花粉,在封闭、模拟制种、开放授粉条件下研究对甘蓝型油菜CMS陕2A、陕3A的辅助授粉效果.结果表明:低浓度糖介质能够在一定程度上保持花粉活力,改善柱头环境,有利于外源花粉附着萌发.低浓度糖介质花粉辅助授粉封闭处理的平均结籽数为1.37~2.13粒/朵,有效角粒数为3.80~4.88粒/角;模拟制种、开放授粉处理均能显著和极显著地增加CMS的结实,较大幅度地提高制种产量,以0.5%糖介质花粉对模拟制种田作模拟制种授粉,可使陕2A、陕3A平均结籽数分别提高2.91粒/朵和2.70粒/朵,增产10.35%和11.52%;而4.0%糖介质和1.0%盐介质对模拟制种田辅助授粉和开放授粉处理却表现显著的负效应.  相似文献   

4.
芝麻花粉附着、萌发与花粉管伸长过程研究   总被引:1,自引:0,他引:1  
以中芝14号为试验材料,采用荧光显微镜和石蜡切片法研究芝麻花粉在柱头上附着、萌发、伸长及在花柱内生长全过程.于授粉后不同时间段连续取样固定,并进行显微观察和数据统计.结果表明,在芝麻柱头上,授粉后5min基本无花粉萌发,10min有极少量花粉萌发,30min大量花粉开始萌发,并长出花粉管.花粉管具明显的绿色荧光,进入羽毛状柱头后继续生长于花柱基部至子房顶部的引导组织内.授粉后2h,生长最快的花粉管已经到达花柱基部,花粉管的平均生长速度约为3.0mm/h.授粉后4h,大量花粉管进入子房.即使在授粉后24h,仍有部分花粉在萌发和生长中.  相似文献   

5.
红麻受精过程的组织解剖学观察研究   总被引:1,自引:0,他引:1  
红麻(Hibiscus cannabinus L.)为锦葵科(Malvacese)木槿属(Hibiscus)一年生韧皮纤维作物.实验利用ITC法与苯胺蓝染色法对红麻离体花粉进行检测,利用组织切片法对授粉后花柱组织进行观察,利用石蜡切片观察子房受精状态.结果如下:花粉离体后,活力在短时间内急剧下降,7h后活力消失殆尽;红麻花粉在培养基(蔗糖硼酸)上,0.5h开始萌发,萌发率可达80%,但花粉管很难继续生长;红麻花粉在柱头上20min开始萌发,授粉4h后花粉管穿过花柱,进入子房;6h左右子房内花粉管通道形成;12h花粉管通过珠孔进入胚囊,释放内含物;18h时观察到合子,完成受精作用;根据试验与田间观察分析,最适外源基因导入的开始时期为授粉后12h.  相似文献   

6.
以中芝14号为试验材料,采用荧光显微镜和石蜡切片法研究芝麻花粉在柱头上附着、萌发、伸长及在花柱内生长全过程。于授粉后不同时间段连续取样固定,并进行显微观察和数据统计,结果表明,在芝麻柱头上,授粉后5min基本无花粉萌发,10min有极少量花粉萌发,30min大量花粉开始萌发,并长出花粉管。花粉管具明显的绿色荧光,进入羽毛状柱头后继续生长于花柱基部至子房顶部的引导组织内。授粉后2h,生长最快的花粉管已经到达花柱基部,花粉管的平均生长速度约为3.0 mm/h。授粉后4h,大量花粉管进入子房。即使在授粉后24h,仍有部分花粉在萌发和生长中。  相似文献   

7.
授粉期间的高温能减少玉米的籽粒数。本研究利用一个双列杂交,通过定测花粉生体外活力、散粉特性及这些性状的配合力来确定雄穗对高温的反应。高温下,未萌发花粉百分率的增加随基因型而异,除B73×Mo和N28×Mo17外,全部基因型均达统计显著平准。在高温下对未萌发花粉Mo17具最佳一般配合力。特殊配合力对未萌发花粉的效应也很显著。高温下雄穗主枝花药伸出程度的减弱在杂交种间不同。Mo17对花药伸出具最佳一般配合力效应。  相似文献   

8.
以耐热水稻品系996和热敏感水稻品系4628为材料,抽穗期在人工气候室进行高温[37℃(09:00—17:00)/30℃(17:00—09:00)]和适温[30℃(09:00—17:00)/25℃(17:00—09:00)]处理,研究高温对水稻开花历期、开花动态、柱头活力、花粉活力、花药开裂和结实率的影响。结果表明,高温胁迫下,两品系均表现为开花历期缩短、日开花时间延长、峰值降低、颖花开颖时间延长、开颖角度增大、花药开裂受阻、花粉活力下降和柱头活力降低,最终导致结实率显著下降。但是,与热敏感品系4628相比,高温下,耐热品系996具有较大的开颖角度和花药开裂系数,较强的花粉活力和柱头活力,较高的结实率和较低的热害指数,表现出较强的耐高温能力。  相似文献   

9.
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   

10.
水稻对减数分裂期高温胁迫的生理响应   总被引:1,自引:0,他引:1  
《杂交水稻》2016,(3):64-67
以水稻耐热品系996、热敏感品系4628为材料,在减数分裂期进行高温处理,以同期自然温度为对照,研究减数分裂期高温对水稻花粉活力、花药开裂、受精率、结实性状及剑叶生理特性的影响。结果表明,高温处理显著降低了花粉活力、花药开裂系数、受精率、结实率,热敏感品系4628下降幅度大于耐热品系996;高温处理降低了热敏感品系4628米粒粒宽,增加了长宽比,对耐热品系996无显著影响;高温下剑叶叶绿素含量、SOD活性、POD活性降低,而MDA含量和相对电导率增加,热敏感品系4628变化幅度大于耐热品系996。  相似文献   

11.
《Plant Production Science》2013,16(3):196-199
Abstract

The changes in pollen grain diameter were examined in relation to the floret opening and anther dehiscence in rice (Oryza sativa L.). In the first experiment, the florets were artificially opened by excising the top of the glumes at various times before the expected natural flowering time. Pollen diameter increased rapidly in the artificially opened florets, but slowly in the controls in which the glumes were left intact. The time of anther dehiscence coincided well with the time when pollen grains reached their maximum diameter. In addition, the pollen grain diameter was significantly correlated with the percentage of dehisced anthers in the florets artificially opened at various times. These results indicate that floret opening induces the swelling of pollen grains and that the swelling is an important event for anther dehiscence. In the second experiment, anther segments with pollen left remaining intact and those with pollen removed were immersed in water. The septa in the anther segments without pollen failed to rupture in water, whereas 70% of the septa in the anther segments with pollen left remaining ruptured, indicating that the septa can be ruptured by the swelling pressure of pollen grains resulting in unfolding of anther locules. From these findings, we infer that the rapid swelling of pollen grains in response to floret opening is a driving force to rupture the septum and unfold the locules.  相似文献   

12.
With global warming, rice plants may be subjected to heat stress more regularly during the heatsensitive flowering stage, causing spikelet sterility and grain yield loss.Stigma exsertion is considered to increase pollen reception and promote female reproductive success.The aim of this study was to investigate the role of stigma exsertion on spikelet fertility at high temperatures.Five rice cultivars(Liangyoupeijiu, Shanyou 63, Huanghuazhan, Nagina 22, and IR64) with differing degrees of stigma exsertion were cultivated and exposed to high temperature at anthesis.Heat-tolerant cultivars did not always show a high percentage of spikelets with exserted stigmas, and vice versa.Irrespective of the presence of more pollen grains on exserted stigmas, spikelets with exserted stigmas did not show greater spikelet fertility than spikelets with fewer exserted stigmas or hidden stigmas under heat stress.GA3 application augmented the percentage of spikelets with exserted stigmas;however, it did not increase spikelet fertility under heat stress.Spikelet fertility of whole panicles was negatively correlated with the percentage of spikelets with exserted stigmas, but positively with that with hidden stigmas.Viability of the hidden stigmas was less reduced than that of exserted stigmas under heat stress, suggesting that hidden stigmas have an advantage in maintaining viability.Heat stress delayed anther dehiscence and reduced the viabilities of both exserted stigmas and pollens, thereby causing low spikelet fertility.Together, these results suggest that high spikelet fertility does not depend on stigma exsertion and that enclosed stigma generally contributes to higher spikelet fertility and heat tolerance under high-temperature conditions during flowering in rice.  相似文献   

13.
《Field Crops Research》2006,97(1):87-100
Field-based screens for genetic variation in reproductive-stage drought tolerance are often confounded by genetic variation in root depth, flowering date and biomass at flowering. To reduce these confounding effects and to impose drought stress more precisely, we grew contrasting genotypes of rice (Oryza sativa L.) in shallow containers of flooded soil. When water was withheld from the shallow-rooted indica genotype IR64 for 6 days starting at −17, −7, 0, 10 and 20 days after heading (DAH), the impact on grain yield was greatest at −7 and 0DAH. The most sensitive yield component was filled grain percentage (spikelet fertility). Data on yield and spikelet fertility were also obtained for another shallow-rooted lowland indica (BRRI Dhan 31) and two deep-rooted upland tropical japonicas (Azucena and Moroberekan). Compared with well-watered controls, withholding of water for 6 days reduced spikelet fertility by ∼80% in IR64, BRRI Dhan 31 and Azucena but by 22% in Moroberekan. In a detailed comparison, water was withheld from IR64 for 5 days and from Moroberekan for 6 days, starting 3 days before the heading date of well-watered controls. Under these stress conditions, heading was delayed for 4 days in IR64 and 6 days in Moroberekan. Spikelet fertility in the top four rachis branches was reduced by 80% in IR64 and 16% in Moroberekan, a difference attributable principally to reduced anther dehiscence and lower stigma pollen density in IR64. Two properties of Moroberekan may contribute to high anther dehiscence after stress/re-watering: (i) constitutively superior development of fibrous structures in the endothecium at the anther apex and base and (ii) better maintenance of pollen size. All ovaries of Moroberekan received pollen—an average of 60 grains in well-watered plants and 42 grains in stressed/re-watered plants. In well-watered IR64, all ovaries received an average of 31 grains, whereas in stressed/re-watered IR64, 67% of ovaries received no pollen and the remainder received an average of eight grains. Moroberekan may, therefore, be a source of reproductive-stage drought tolerance through genes that maintain anther dehiscence during recovery from low water status.  相似文献   

14.
气候因子对杂交稻金优组合结实率的影响研究   总被引:3,自引:0,他引:3  
采用分期播种和定穗观察的方法研究了不同气候因子对金优组合结实率的影响。结果表明,在相同气候条件下,金优组合与对照汕优、威优组合相比,结实率没有明显差异;对不良气候条件的抗逆能力相当。同时还得出,影响杂交稻结实率的主要气候因子是灌浆结实阶段的日平均温度和抽穗扬花及灌浆结实阶段的降雨量  相似文献   

15.
水稻籼粳亚种间杂种小穗不孕的细胞学研究   总被引:18,自引:1,他引:18  
 利用携有广亲和基因的杂种和普通籼粳杂种为材料以揭示籼粳杂种配子体发育特征及其影响小穗不孕的主要因素。结果显示:杂种雌雄配子体均出现不同程度的败育,并均与大小孢子第一次有丝分裂异常有关;杂种的小穗育性主要受胚囊育性、花粉育性及花药开裂特性所控制,后两者通过影响柱头上花粉的萌发量而决定小穗的受精。  相似文献   

16.
Rice spikelet rot disease (RSRD), caused by Fusarium proliferatum, is an emerging disease. So far, the effects of diseased rice floral organs as well as the primary infection sites and stages of this pathogen are not determined. We investigated changes in the floral organs, along with the infection processes of the pathogen in plants inoculated with F. proliferatum and labelled with a green fluorescent protein during different growth stages of rice. The results showed that RSRD is not a systemic infectious disease, which has negative effects on the fertility of the infected rice. F. proliferatum caused brown colored anthers, crinkled pistils and ovaries, pollen grain deformities and anther indehiscence. The number of pollen grains on the stigmas decreased significantly in the infected spikelets, and the anther dehiscence and seed-setting rate successively declined by 69% and 73%, respectively, as a result of the infection. The initial infection stage occurred at the pollen cell maturity stage, and the primary invasion sites were determined to be the anthers of rice. It was noted that the pathogen mainly damaged the pollen cells, and with the exception of the filaments, proceeded to colonize the pistils and endosperm.  相似文献   

17.
This study was conducted to clarify the relationship between the number of pollen grains per anther and spikelet fertility under low temperature conditions in the rice cultivars and lines including lines with quantitative trait loci (QTL) for cold tolerance, adapted to the Tohoku region of northern Japan. Cold-water treatment decreased anther length, the number of pollen grains per anther, and spikelet fertility in all cultivars and lines. The number of pollen grains was proportional to anther length in all cultivars and lines and under all temperatures. Spikelet fertility decreased with decreasing the number of pollen grains in cold-water treatments at 18.5 and 19.3?°C. ‘Ouu 415’, with the qLTB3 QTL for cold tolerance, had 28% more pollen grains and 9% higher spikelet fertility than the recurrent parent, ‘Hitomebore’, in the 18.5?°C cold-water treatment, suggesting that qLTB3 increased both parameters. Lines with the qCTB8 QTL for cold tolerance had significantly more pollen grains in two of the three years and significantly higher spikelet fertility in all three years in the 19.3?°C cold-water treatment, suggesting that qCTB8 reinforced cold tolerance. Ctb1, a proposed cold-tolerance QTL, had no effect on the number of pollen grains or spikelet fertility. In conclusion, the cultivars and lines with more pollen grains had a higher cold tolerance. Some of QTLs were inferred to increase the number of pollen grains and reinforce cold tolerance.  相似文献   

18.
两系杂交稻扬两优6号源库特征与结实特性的分析   总被引:10,自引:1,他引:9  
以两系杂交稻扬两优6号和两优培九及三系杂交稻汕优63为材料,研究了源、库、流特征及其与籽粒充实的关系。 扬两优6号和汕优63的结实率、籽粒充实度和产量明显高于两优培九;扬两优6号和汕优63茎鞘物质输出率和转换率显著高于两优培九;扬两优6号和汕优63籽粒中蔗糖合成酶、腺苷二磷酸葡萄糖焦磷酸化酶、淀粉合成酶和淀粉分支酶的活性显著高于两优培九,且上述各酶的活性与籽粒最大灌浆速率、平均灌浆速率、谷粒充实度和粒重呈极显著的正相关;扬两优6号和汕优63的单位维管束和韧皮部的颖花负荷、现实产量负荷、总库容负荷显著小于两优培九,且负荷越大的组合结实率就越低,充实度也就越差。扬两优6号单位面积韧皮部的物质转运速率显著高于两优培九和汕优63。表明扬两优6号具有源足、库强、流畅的特点,这是它结实率高和籽粒充实度好的生理基础。  相似文献   

19.
比较了亚种间杂交稻赣化7号与品种间杂交稻汕优63的枝梗和颖花的分化及发育特性,分析了颖花的分化、发育及一、二次枝梗对大穗形成的作用,提出了增加颖花数的主攻方向。  相似文献   

20.
水分胁迫下外源多胺对水稻叶片光合速率与籽粒充实的影响   总被引:25,自引:0,他引:25  
 以汕优63和PC311/早献党18为材料,研究了不同程度土壤干旱胁迫下水稻叶片中多胺含量变化以及外源多胺对籽粒充实和粒重的影响。在水分胁迫条件下,叶片中腐胺含量和腐胺与亚精胺以及精胺的比值提高。无论在土壤水分充足或水分胁迫条件下,抽穗期施用低浓度Spd和Spm后,叶片中的腐胺和MDA含量降低,而亚精胺和精胺、光合作用速率和籽粒的胚乳细胞数,饱满籽粒百分率以及千粒重显著增加。  相似文献   

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