水稻颖花开裂SRS突变体的鉴定

利用扫描电镜观察了水稻（Ｏｒｙｚａ ｓａｔｉｖａ Ｌ．）颖花开裂突变体ＳＲＳ（ｓｐｌｉｔ ｒｉｃｅ ｓｐｉｋｅｌｅｔ）花器官形态发生过程,该突变体表现为内外稃变软变长,不抱合,外稃基部又着生一颖花,浆片呈稃片状,但是雌雄蕊着生位置和形态表现正常。利用ＳＲＳ突变体为父本,“窄叶青８号”为母本配制杂交组合,其Ｆ２代群体中正常与突变植株的分离比例为３：１,表明该突变性状是由单隐性基因控制的。作为对照,同     

海韭菜的花器官发生

运用扫描电镜（SEM）观察了海韭菜（Triglochin maritimum）的花器官发生发育过程。结果表明：海韭菜花发育是典型的单子叶植物发生模式,即两轮花被片、两轮雄蕊和两轮心皮以三基数轮状交替发生,花器官是以向心向顶的方式发生的,未发现“花被片—雄蕊复合原基”。 发育后期雄蕊和与之对生的花被片之间的共同基部可能是相继向上居间生长的结果。花被片轮和雄蕊轮二者之间在发育位置、时间和速率上存在差异,内轮花被片原基和外轮雄蕊原基的不同发育时间和发育速度使得在成熟花中内轮花被片位于外轮雄蕊的内方。观察结果不支持水麦冬属植物的花是退化（或压缩）的花序侧分枝等假花的观点。     

一个水稻畸形颖壳突变体ah的鉴定及其突变性状的遗传分析

水稻畸形颖壳突变体ah是双胚苗品系W2555中自然突变产生的。该突变体的内外稃畸形,退化;雄蕊雌蕊化,雌蕊败育;浆片同源转化为类内外稃的结构,推测该突变体可能影响B功能基因的正常发育。与野生型相比,突变体的小穗分支稀疏,每级枝梗上颖花数目减少,一般为4～6朵;小穗顶端的颖花经常不能成熟,表现为颖花始终泛白,不能转绿,因此该突变也影响花序分生组织的发育。进一步的研究证明,该突变体的发育受外界环境的影响。突变性状的遗传分析表明,该突变体由单隐性基因控制。     

水稻花器官突变体apl (abnormal palea and lodicules) 的表型分析与基因初定位

水稻(Oryza sativa)是重要的粮食作物, 其花器官的正常起始及形态建成直接影响水稻的产量。为了深入分析水稻小花发育的调控机理, 从已构建的水稻EMS诱变突变体库中筛选获得了一个花器官异常发育的突变体apl (abnormal palea and lodicules)。与野生型相比, apl突变体小花的内稃膨大, 浆片伸长或转换成稃状结构, 雄蕊数目减少, 表明APL基因可能参与调控水稻内稃、浆片和雄蕊等多轮花器官属性的建成。遗传学分析表明, 该突变体性状受1个隐性单基因控制。通过图位克隆, 将APL基因初步定位于1号染色体上。该工作为深入研究APL基因在水稻花器官形态建成中的作用机制奠定了基础。     

拟南芥ASL25/LBD28基因过量表达对叶片形态建成的影响

为研究ASL25/LBD28基因在植物发育过程中的作用,该研究构建了拟南芥ASL25/LBD28的过量表达载体并将其转入野生型拟南芥中,结果发现,ASL25/LBD28基因的过量表达可导致转基因拟南芥的叶片变得狭长;在叶极性发育突变体as2中,ASL25/LBD28基因过量表达导致部分转基因植株在形成1～3片畸形叶后顶端分生组织的发育会终止;而许多转基因植株则会形成许多"针状"叶.扫描电镜观察表明,不正常的叶片近轴面或"针状"叶的表皮细胞具有远轴面化的长条形细胞,说明在as2突变体中过量表达ASL25/LBD28基因影响叶片的极性发育.     

水稻花器官突变体apl（abnormal palea and Iodicules）的表型分析与基因初定位

水稻（Oryzasafiva）是重要的粮食作物,其花器官的正常起始及形态建成直接影响水稻的产量。为了深入分析水稻小花发育的调控机理,从已构建的水稻EMS诱变突变体库中筛选获得了一个花器官异常发育的突变体apl（abnormal palea and Iodicules）。与野生型相比,apl变体小花的内稃膨大,浆片伸长或转换成稃状结构,雄蕊数目减少,表明APL基因可能参与调控水稻内稃、浆片和雄蕊等多轮花器官属性的建成。遗传学分析表明,该突变体性状受1个隐性单基因控制。通过图位克隆,将APL基因初步定位于1号染色体上。该工作为深入研究APL基因在水稻花器官形态建成中的作用机制奠定了基础。     

一个水稻颖花器官突变体的形态解剖分析(英文)

从水稻 (OryzasativaL .)育种后代材料中获得一个受单隐性基因控制的颖花器官突变体。该突变体的内外稃变型、退化 ;雄蕊雌蕊化 ,每个颖花含 1～ 3个发育完整的雌蕊 ,其他雌蕊发育不完全。有的雌蕊化的雄蕊下部为花丝 ,其上着生不规则膨大组织和 0～ 3个羽毛状柱头。横切面和纵切面观察均可见每个颖花含 3个子房。人工辅助授粉后 ,每个颖花可产生 1～ 2粒种子。根据这些结果推断 ,该突变体为类似B功能缺失的突变体。     

棉花叶皱小突变体的遗传分析及激素含量研究

在海岛棉(Gossypium barbadense L.)品种海7124的基因组总DNA导入陆地棉(G.hirsutum L.)品种石远321的后代中,发现了一个形态性状发生变异的突变体。与正常棉株相比,突变体叶片皱小、茎杆细弱,铃小但种子发育正常。叶表皮显微观察发现,突变体叶表皮细胞增大,突变体叶片变小是由于叶片细胞数目的减少。遗传分析表明,突变体为杂合基因型,突变性状受显性基因控制,并可能具有纯合致死效应。内源激素含量测定显示,突变体茎尖中IAA和ZR含量显著高于正常棉株,推测突变体的叶片皱缩变小可能与主茎顶芽中IAA和ZR含量的异常有关。     

一个新的水稻花器官数目突变体fon(t)的鉴定及分析

水稻花器官数目突变体 fon(t)是在单倍体与二倍体的杂交 F2代发现的,经过多代种植,已稳定遗传。以 fon(t)为父本,以日本晴、93?11 和 R527 为母本配制杂交组合进行遗传分析,根据 F2代表型及χ2测验结果表明,该突变体的性状是由单隐性基因控制的。因为对花器官数目突变体曾有报道如 fon1、fon2 和 fon3,所以该突变体暂定名为 fon(t)。该突变体导致内外稃开裂,花器官外露;雄蕊和雌蕊的数目均增多,雄蕊一般 6~9 枚,雌蕊 1~2 枚;浆片同源转化为类内稃的结构;个别的花器官中还出现花丝上伸出类柱头的结构,浆片上部同源转化为类柱头或者类雄蕊的结构。研究结果表明,fon(t)基因可能影响水稻第三、四轮花器官的数目以及第二轮浆片的发育。     

一个水稻颖花器突变体的形态解剖分析

从水稻（Ｏｒｙｚａ ｓａｔｉｖａ Ｌ．）育种后代材料中获得一个受单隐性基因控制的颖花器官突变体,该突变体的内外释变,每个颖花含１～３个发育完整的雌蕊,其他雌蕊发育不完全。有的雌蕊化的雄蕊下部为花丝,其上着生不规则在组织和０～３个羽毛状柱头。横切面和纵切面观察均可见每个颖花含３个子房。人工辅助授粉后,每个颖花可产生１～２粒种子根据这些结果推断,该突变体为类似Ｂ功能缺失的突变体。     

黄瓜矮生突变体C1056的茎解剖结构及其生理特性分析

该研究以黄瓜矮生突变体C1056和野生型CCMC为材料,对其主要生理特性、叶绿体超微结构以及茎显微结构进行了观察、测定和比较分析,以探讨黄瓜株高调控机理并挖掘新的矮化种质,为黄瓜的矮化育种提供依据。结果显示:(1)突变体C1056的株高较野生型极显著变矮,且叶色加深、叶脉加粗、叶尖内卷、叶片皱缩,但茎粗、节间数与野生型无显著差异,而节间长度极显著低于野生型。(2)茎横切显微结构显示,突变体的维管束数量与野生型无显著差异,但导管直径缩小;纵切结果显示,突变体茎节间细胞长度变短,细胞变小,细胞数目略有补偿。(3)与野生型相比,突变体的叶绿素和类胡萝卜素含量均有不同程度的下降,叶绿素/类胡萝卜素和叶绿素a/b的比值明显增高。(4)突变体叶绿素荧光各参数与野生型相比无明显变化;突变体的净光合速率较野生型降低8%,气孔导度、蒸腾速率较野生型分别提高15%和10%,但差异均不显著,而胞间CO2浓度显著高于野生型。(5)透射电镜观察结果发现,与野生型相比,突变体的叶肉细胞比较小,叶绿体所占细胞面积明增大,且叶绿体形状为半圆形和纺锤形,部分非正常结构的叶绿体的大部分基质、基粒片层未完全分化且不清晰,垛叠不整齐。研究表明,黄瓜矮生突变体C1056的矮化主要因其节间长度缩短以及细胞变小所致,且突变体的叶绿体结构受到一定程度的影响,但并未明显影响其光合能力。     

Phycobilisome composition and possible relationship to reaction centers

The photosynthetic apparatus was studied in Anacystis nidulans wild type and in a spontaneous pigment mutant 85Y which had improved growth in far-red light (greater than 650 nm). Two phycobiliproteins, C-phycocyanin (lambda max 625) and allophycocyanin (lambda max 650), were present in a molar ratio of approximately 3:1 in the wild type and approximately 0.4:1 in the mutant. Phycobilisomes of wild type cells were larger (57 X 30 nm) than those of the mutant 85Y (28 X 15 nm). In the mutant they seemed to consist primarily of the allophycocyanin core. Fluorescence emission maxima of wild type and mutant 85Y phycobilisomes were at 680 nm (23 degrees C) and 685 nm (-196 degrees C). Excitation maxima of phycobilisomes were at 630 and 650 nm for the wild type and the mutant 85Y, respectively. The phycobilisomes of wild type cells whether grown in white or far-red light had the same size and pigment composition. A typical wild type cell in white light had a thylakoid area of 22.8 microns 2, but in far-red light the area was reduced to 13.5 microns 2, which was close to that of 85Y at 13.6 microns 2. Chlorophyll molecules per cell decreased in far-red light from 1.1 X 10(7) in wild type (white light) to 4.5 X 10(6) in mutant 85Y (far-red). The number of phycobilisomes per cell (approx 2 X 10(4)), calculated from the phycobiliprotein content and phycobilisome size, was about the same in wild type (white light) and mutant 85Y (far-red light), but the number of phycobilisomes per unit area of thylakoid was significantly greater in mutant 85Y than in wild type. The present results suggest that the phycobilisomes are linked with reaction centers and that the PSII complement (photo-system II and phycobilisome) was fully maintained in far-red light.     

一份水稻叶片反卷突变体的遗传分析及电镜显微观察

叶片是植物进行光合作用的重要器官。叶片适度卷曲能够提高水稻(Oryza sativa)生长中后期群体基部的光能利用率, 因而有利于水稻产量的提高。该研究首先在水稻T-DNA插入突变体库中发现一份叶片反卷的突变体。遗传分析表明, 该性状受到1对隐性核基因控制。扫描电镜观察结果显示, 突变体成熟叶片上下表皮的气孔发生了畸变; 且叶片上表皮气孔数目增多, 而下表皮气孔数目与野生型基本相同。叶片横切面电镜观察结果表明, 与野生型相比, 突变体叶片的泡状细胞数目和面积在早期(二叶期)就开始增加, 在成熟期更加明显, 这可能是导致叶片反卷的主要原因。     

The effect of low temperature on patterns of cell division in developing second leaves of wild-type and slender mutant barley (Hordeum vulgare L.)

This study reports on investigations into the effect of long-term growth at reduced temperatures on cell elongation and cell division in the wild type and a temperature-insensitive ( slender ) mutant of barley. Plants were grown under two temperature regimes (20 and 5 °C) and the mitotic index, cell doubling time and cell lengths over the division and elongation zone were monitored at several stages of development in the second leaf. Leaf length and leaf growth rates were characteristically greater in the slender mutant than in the wild type and this was greatly exaggerated by growth at low temperature. Cell length and the length of the division zone were also greater in the slender mutant than in the wild type, and growing the plants at reduced temperature (5 °C) shortened cell lengths only in the wild type. The slender mutant had a higher mitotic index than the wild type, although in neither genotype was change in the mitotic index observed following growth at reduced temperature. Cell doubling time, on the other hand, was reduced by growth at reduced temperature in the wild type but not in the slender mutant. Thus, the data suggest very different growth responses to low temperature in the two genotypes. The results are discussed in terms of the ability of plants to sense their environment and optimize their metabolism for future growth.     

VASCULAR SYSTEM OF THE FLORET OF LEERSIA VIRGINICA (GRAMINEAE-ORYZOIDEAE)

The vascular system of the floret of Leersia is unified yet is segmented according to the appendages it serves. The rachilla at the floret base contains a collateral bundle related to the median trace of the lemma. The palea median trace joins the posterior of this bundle in the rachilla as the lemma laterals merge with the anterior. Although the stamen traces enter at the flanks of this rachilla bundle, they do not become fully incorporated into the system until near the floret base where the rachilla bundle, lemma laterals, and palea laterals converge. Traces from the lodicules attach to the anterior of the stamen traces. The base of the vascular system of the pistil, the pistil plexus, attaches tenuously by a bundle to the lower system between the entrance of the stamen traces. A bundle from each style attaches near the anterior of the pistil plexus below the level where the posterior of the pistil plexus rises, as the placental bundle, to merge with the ovule. Characteristics of the vascular system of Leersia, such as the relative discreteness of the staminal and stylar traces and the lack of both the anterior pistil bundle and the xylem discontinuity, are useful for delimiting the Oryzoideae from the Festucoideae.     

Atypical Granules in the Eyes of the White Mutant of Drosophila melanogaster Are Lysosome-Related Organelles

In the pigment cells of the white mutant of Drosophila melanogaster, as described earlier, two types of abnormal granules are found by conventional electron microscopy. However, both types of abnormal granules, in addition to those in pigment cell invaginations, are also present in the cytoplasm of the photoreceptor cells. Three enzymes (acid phosphatase, peroxidase, and tyrosinase) are localized within the eyes of wild type and white mutant Drosophila melanogaster by electron microscopy. Peroxidase activity is present in lamellar bodies close to the rhabdomeral microvilli of both fly types. However the organelles containing peroxidase activity are 6-fold more frequent in the wild type than in the mutant. Acid phosphatase is present in lamellar bodies between and at the bases of the rhabdomeral microvilli of the wild type, as well as in ommochrome granules of the photoreceptor cells. In the white mutant, however, acid phosphatase was located in electron lucent vacuoles in the cytoplasm of the receptor cells. These acid phosphatase-positive vacuoles also contained both types of abnormal granules. The latter result indicates that abnormal granules in the receptor cells originate from lysosomal degradation and that targeting of lysosomal enzymes is altered in the white mutant. Due to the tyrosinase activity in the hemolymph of flies, the extracellular spaces are electron dense after DOPA incubation. Since some abnormal granules within the photoreceptor cells are not surrounded by an extracellular space, they can be assumed to originate within the photoreceptor cells.     

超大型烟草突变株的生理生化特征和分子生物学鉴定

超大型烟草突变株再生植株高度是野生型的2．2倍,叶片数是野生型的3．3倍,呈现晚花发育特征;叶片气孔保卫细胞中叶绿体数是野生型的1．3倍,叶绿素a、b和叶绿素总量均高于野生型,可溶性蛋白质含量是野生型的1．18倍,过氧化物酶、细胞色素氧化酶同工酶电泳图谱上有一定差异;可溶性蛋白SDS-PAGE电泳图谱上比野生型少4条谱带;RAPD结果表明突变体在DNA水平上确实发生了变化,DDRT-PCR结果显示出两者在基因表达上有差异。突变株再生植株可以开花结实,植株高大、叶数多,晚花的特征可以稳定遗传。     

Proteome analysis and characterization of phenotypes of lesion mimic mutant spotted leaf 6 in rice

Rice spotted leaf 6 (spl6) mutant produces lesions caused by spontaneous cell death in the absence of pathogenic infection. Expression of this genetic trait was developmentally programmed. After the tillering stage, small red and brown lesions were initiated in groups on the leaf blade. Eventually, the lesions formed parallel lines along the midrib of the leaf. Under light and transmission electron microscopy, we observed that thylakoid membranes of mesophyll chloroplasts were progressively damaged in the nonspotted section of the mutant leaf. However, chloroplasts were absent in the mesophyll cells of the spotted area of the spl6 mutant. These results indicated that lesion formation of the spl6 mutant might be caused by oxidative burst. Proteome analysis revealed that 159 protein spots were up or downregulated in comparison between spotted leaves of the spl6 mutant plants and normal leaves of the wild type. Among them, protein disulfide isomerase (PDI), transketolase, thioredoxin peroxidase (TPX), ATP synthase, RuBisCO large subunit, and RuBisCO activase small subunit were not identified in the spl6 mutant but were abundant in the wild type. Especially, the absence of TPX and PDI might be the cause of the failure to protect cells against oxidative burst resulting in degradation of the thylakoid membranes and leading to programmed cell death and lesion development.