DEAMINATION OF DEOXYCYTIDINE AND 5-METHYLDEOXYCYTIDINE IN DEVELOPING ANTHERS OF LILIUM LONGIFLORUM (VAR. CROFT)

A study has been made of developmental variations in anthers of Lilium longiflorum with respect to the deamination of deoxycytidine and 5-methyldeoxycytidine. Although a periodicity of enzymatic activities surrounding the mitotic cycle has been found, the over-all evidence is against the significance of such periodicity to chromosome duplication. On the basis of evidence obtained a distinction has been drawn between enzyme systems functioning in a broad supporting role and those immediately tied to morphogenetic events.     

THERMOMORPHOGENESIS IN LILIUM LONGIFLORUM

Stem elongation and leaf orientation in Lilium longiflorum Thunb. were influenced more by the difference (DIF) between day temperature (DT) and night temperature (NT) than absolute DT or NT from 14 to 30 C. Plant height and internode length increased 129 and 382%, respectively, as DIF (DT-NT) increased from –16 to 16 C as compared to only 15 and 58% when either DT or NT was increased from 14 to 30 C, respectively. Leaf orientation, defined as the angle between a line perpendicular to the stem and the line from the leaf base to the leaf tip, increased 43° (leaves became more upright) as DIF increased from –16 to 16 C. In contrast to plant height, internode length, and leaf orientation, leaf and flower length were influenced more by absolute temperature than DIF. Leaf and flower length decreased 32 and 14%, respectively, as NT increased from 14 to 30 C. DT had little effect on either leaf or flower length. The influence of DIF on stem elongation suggested that thermomorphogenesis was not a function of total plant carbohydrate or carbohydrate translocation. Instead, DIF appeared to influence the endogenous gibberellin content or the response of plant tissue to gibberellin. Similarities between thermomorphogenic plant responses and photomorphogenic plant responses suggested that these two processes may be related with respect to their perception and/or transduction.     

PARTHENOGENESIS IN TETRAPLOID LILIUM LONGIFLORUM

Emsweller , S. L., and Joseph Uhring . (U.S.D.A., Beltsville, Md.) Parthenogenesis in tetraploid Lilium longiflorum. Amer. Jour. Bot. 49(9): 978–984. Illus. 1962.—Nine maternal polyhaploids from 1 capsule and 1 tetraploid from another were produced following pollination of 2 tetraploid Lilium longiflorum plants with pollen from diploids of the same species. One of the 9 plants had 25 chromosomes; the extra chromosome was identified as a modified D. Two other plants had 2 new chromosomes each and the remaining 6 had 24 unmodified chromosomes. Translocations in meiosis of the tetraploid produced the new chromosomes. One plant obtained from a second capsule had 48 chromosomes. The 9 plants were smaller than diploids and the 48-chromosome plant was considered a diploid until mitosis was observed. The 9 plants originated from unfertilized eggs of the tetraploid, and the 48-chromosome plant presumably from chromosome doubling of an egg cell.     

SECRETIONS FROM THE PISTIL OF LILIUM LONGIFLORUM

The pistil of Lilium longiflorum secretes two forms of exudate, one from the stigma surface and the other from the canal cavity. Electrophoretic studies of these exudates have revealed quantitative and qualitative differences in protein profiles. The exudatic components which are transferred to the cell wall by endoplasmic reticulum and Golgi vesicles, are stored within the cell wall of the secretive tissues and secreted from the cell walls directly. The cell wall structure of these secretive tissues differs. The canal cell wall has thick characteristic ingrowths that are supplied mainly from Golgi vesicles, while the papilla cell wall of the stigma is thinner, lacks ingrowths, and is supplied from ER vesicles.     

STUDIES ON THE SELF-INCOMPATIBILITY RESPONSE OF LILIUM LONGIFLORUM

Removal of substances loosely associated with the wall of Lilium longiflorum pollen did not affect in vitro germination and tube growth, tube growth within compatible styles, or production of viable seeds. Nor was growth of pollen tubes within incompatible styles enhanced by prior removal of the loosely bound materials. Hence, these materials appear not to be recognition factors in the gametophytic self-incompatibility system of Lilium and to have no role in pollen germination. Heat treatment of selected portions of lily pistils prior to pollination indicated that the incompatibility factor(s) was located in the lower half of the style, and that the stigma plays no role in incompatibility.     

AUTORADIOGRAPHIC STUDIES OF NUCLEIC ACIDS AND PROTEINS DURING MEIOSIS IN LILIUM LONGIFLORUM

Taylor , J. Herbert (Columbia U., New York, N. Y.) Autoradiographic studies of nucleic acids and proteins during meiosis in Lilium longiflorum. Amer. Jour. Bot. 46(7): 477–484. Illus. 1959.—A study was made of the incorporation of glycine-C¹⁴, orotic acid-C¹⁴ and cytidine-H³ into nucleic acids and proteins of sporogenous and tapetal cells of lily anthers preceding and during meiosis. Methods for differential extraction of nucleic acids from tissue sections, which had been frozen, dehydrated by alcohol-substitution, and fixed in hot alcohol, were tested by chromatographic analysis of extracts. Both acid and enzyme hydrolysis were shown to be useful for quantitative or, at least, semi-quantitative work. DNA synthesis was shown to occur only during premeiotic interphase in sporogenous cells, but at two intervals in tapetal nuclei, once when the microsporocytes are in zygotene and again during pachytene. Each time the synthetic period was followed by a normal mitosis. Accumulation of RNA in microsporocytes occurred at stages up to late leptotene. After this period, labeled RNA accumulated almost exclusively in their nuclei and at a slower rate than in earlier stages. DNA synthesis, as measured by incorporation of glycine-C¹⁴ and orotic acid-C¹⁴, gave the same results and confirm earlier results with inorganic phosphate-P³². For RNA, glycine-C¹⁴ and orotic acid-C¹⁴ gave different results. When glycine-C¹⁴ was the source of label, incorporation of C¹⁴ in RNA stopped during DNA synthesis in sporogenous cells. Glycine-C¹⁴ was not utilized to a significant extent at any time by tapetal cells for RNA synthesis, but extensively for DNA and protein synthesis. Orotic acid-C¹⁴ was incorporated into RNA of both tapetum and sporogenous cells at various periods in development apparently including the interval of DNA synthesis. Protein synthesis as measured by incorporation of glycine is relatively rapid during premeiotic interphase and leptotene. It continues during the remainder of prophase, but at a much reduced rate. In tapetal cells the rate is rapid in the nuclei during periods of DNA synthesis, but even faster in both cytoplasm and nucleus after divisions are completed and the microsporocytes are in late prophase and division stages. This period of synthesis is perhaps necessary for the postmeiotic functioning of tapetum when it appears to secrete the wall materials for the microspores.     

优质蛋白玉米胚乳贮存蛋白积累的电泳分析

玉米胚乳的２２ ｋＤ和２０ ｋＤ醇溶蛋白在授粉后１５ 天开始积累,编码２２ ｋＤ 和２０ ｋＤ醇溶蛋白的结构基因在胚乳发育过程中同时表达。优质蛋白玉米和ｏ２ 玉米的胚乳中,２２ ｋＤ和２０ ｋＤ醇溶蛋白的合成受到抑制,即ｏ２ 基因对２２ ｋＤ和２０ ｋＤ醇溶蛋白的合成有负的调节作用。Ｍｏ１７／ｏ２ 和Ｍｏ１７ 胚乳醇溶蛋白的双向电泳结果表明,Ｍｏ１７／ｏ２ 的２７ ｋＤ、２２ ｋＤ、２０ ＫＤ和１５ ｋＤ醇溶蛋白的合成均受到强烈的抑制。遗系０４１／ｏ２ 和遗系０４０／ｏ２ 胚乳醇溶蛋白的双向电泳结果表明,二者只在高分子量的蛋白质斑点区域有一些细微的差别。可溶性蛋白的ＳＤＳ－ＰＡＧＥ分析表明,Ｍｏ１７／ｏ２ 胚乳的可溶性蛋白比其同型系Ｍｏ１７ 少３８．７ ｋＤ 和２６．７ ｋＤ两条谱带,多２７．２ ｋＤ和２６．１ ｋＤ两条谱带。二者出现的可溶性蛋白的差异是ｏ２ 基因调控的结果。遗系０４１／ｏ２ 胚乳的可溶性蛋白比其同型系０４０／ｏ２ 多１８．６ ｋＤ和１７．６ ｋＤ两条谱带,少４０．２ ｋＤ 一条谱带,这与ｏ２ 基因修饰因子的作用密切关联     

水稻雄性不育与花药中类脂褐素的积累

细胞质雄性不育水稻不育系珍汕９７Ａ和其保持系珍汕９７Ｂ,处于不育期的光（温）敏核不育水稻Ｗ６１５４ｓ和培矮６４ｓ的花药中类脂褐素（ＬＦＬＰ）含量随花粉发育或败育而增高．不育花药中ＬＦＬＰ的形成速率比可育花药快,三核期的珍汕９７Ａ和不育期Ｗ６１５４ｓ的花药,其ＬＦＬＰ比相应具育性花药高２４％．用抗氧化剂ＧＳＨ、ＢＨＴ和Ｎ２处理离体的单核期花药,发现ＧＳＨ可降低珍汕９７Ａ和不育期的Ｗ６１５４ｓ的ＬＦＬＰ含量．结果认为,水稻雄性不育与膜脂过氧化作用的荧光产物类脂褐素的积累有关．     

EFFECT OF FLORAL AGING ON THE GROWTH OF COMPATIBLE AND INCOMPATIBLE POLLEN TUBES IN LILIUM LONGIFLORUM

Compatible and incompatible pollen tube growth in detached styles of three Lilium longiflorum cultivare varies with the physiological age of the style. Before anthesis both compatible and incompatible pollen tubes grow, in 48 hr, only a fraction of the distance compatible tubes grow after anthesis. Incompatible pollen tubes are restricted to about half the distance of compatible tubes in the four days postanthesis, but thereafter increase up to or three-fourths or more the length of compatible tubes at the time of floral senescence. About 10 days after anthesis, growth of both types of pollen tubes decreases. The detached style method of pollen-tube cultivation is validated in the cultivar ‘Ace’ by seed set obtained following self-pollination in the 6- to 9-day interval and failure of seed set after either self- or cross-pollination after 9 days following anthesis. Also, in agreement with detached style data, self-pollination fails to produce seeds when attempted in bud stages or the five days following anthesis. Cross-pollinations are successful in this period. This material and technique appear well suited for study of the nature of the self-incompatibility reaction.     

NUCLEAR PROTEIN PATTERNS IN DEVELOPING AND ADULT BRAIN AND IN ETHYLNITROSOUREA-INDUCED NEUROECTODERMAL TUMOURS OF THE RAT1,2

In a comparative study, the patterns of histones and non-histone proteins were analysed in the chromatin of foetal (18th day of gestation), 10-day-old, and adult BD IX-rat brain, as well as in the chromatin of two ethylnitrosourea-induced neuroectodermal tumours (TV1A1 and GV1A1) and the corresponding malignant cell culture lines TV1C1 and GV1C1. Separation of nuclear proteins at high resolution was obtained by electrophoresis in 15% and 10% polyacrylamide gels containing urea (2·5 m or 6·25 m ). In spite of an overall similarity, significant quantitative and qualitative differences were observed between the respective non-histone proteins banding patterns of normal brain and the neoplastic cells analysed. The non-histone protein banding patterns of brain (∼40 different bands) at different stages of development revealed both quantitative differences and the presence of particular bands characteristic of foetal or adult brain, respectively. Both the‘foetal’and‘adult’non-histone protein bands also appeared in the electrophoretograms of the neoplastic neuroectodermal cells.     

Three-dimensional aspects of EXINE INITIATION AND DEVELOPMENT IN LILIUM LONGIFLORUM (Liliaceae)

Pollen development in Lilium longiflorum was reinvestigated with high resolution scanning electron microscopy, with special attention to three-dimensional conformation in the exine pattern formation. At the early tetrad stage, the invaginated plasma membrane takes the form of a reticulate pattern that corresponds to the mature exine tectum. Protectum is the first exine layer to be deposited on the reticulate-patterned plasma membrane. The initial protectum consists of aggregated fibrous threads and granules. Subsequently, probacules are formed under the protectum on the plasma membrane. At the free microspore stage the developing exine becomes further enlarged and the protectum develops into mature verrucate muri. The present three-dimensional investigation conflicts with the previous studies on exine development in Lilium.     

SPIRAL DEVELOPMENTAL PATTERNS IN THE STEM AND INFLORESCENCE OF LILIUM TIGRINUM

Extensive correlations in spirality were observed among vegetative and floral organs in Lilium tigrinum Ker. Organs involved were vegetative leaves, bracts, and bracteoles. These correlations varied in their degree of constancy depending upon the organs involved. The mature inflorescences of L. tigrinum appeared to fit the common definition of a raceme. In 67.3% of the flowers at node 3 on the raceme, the bract-bracteole spirals reversed the spiral of vegetative leaves on the stem. These reversals resembled those observed on essentially cymose inflorescences of certain members of the Caryophyllaceae. Cymose branching was found to be an invariable feature of the inflorescence of L. tigrinum when secondary flowers appear. The apparently indeterminate tips of inflorescence main axes were interpreted as exhibiting stages in progression from a basically determinate (cymose) inflorescence. It was concluded that the ancestors of L. tigrinum had well-developed cymose branching patterns in the inflorescence. Reversal of stem spirals by the bract-bracteole spirals at the apices of many inflorescences was considered to be the result of complete utilization of the inflorescence meristem. Explanations for those reversals were provided by the field theory and by the theory of the first available space.     

POLLEN TUBE GROWTH AND INCOMPATIBILITY FOLLOWING INTRA- AND INTER-SPECIFIC POLLINATIONS IN LILIUM LONGIFLORUM

The growth of pollen tubes of a sampling of Lilium species in styles of L. longiflorum incubated at 24 C for 48 hr after pollination indicated two types of interspecific incompatibility. Pollen tubes of two self-compatible species of section Leucolirion, the section including L. longiflorum, stopped growth abruptly upon reaching the stylar canal, were of abnormal morphology, and were incapable of continued growth with longer incubation. Pollen tubes of self-compatible or self-incompatible species of sections Sinomartagon, Pseudolirium, Liriotypus, and Daurolirion approached but did not exceed the length of intraspecific incompatible pollen tubes in styles of L. longiflorum. Pollen tube morphology was normal and tubes were capable of continued growth with additional incubation. Unilateral interspecific incompatibility occurred in reciprocal crosses between self-incompatible L. longiflorum and self-compatible L. regale and L. formosanum, but exceptions occurred in Aurelian hybrids. Incubation of interspecifically pollinated L. longiflorum styles at 39 C, which removes the self-incompatibility reaction, had no effect on interspecific incompatibility.     

高,低蛋白含量的大豆种子贮藏蛋白积累的比较研究

利用ＳＤＳ－ＰＡＧＥ及电子显微镜等技术比较分析和观察了两个大豆品种（Ｇｌｙｃｉｎｅ ｍ ａｘ（Ｌ．） Ｍｅｒｒ．）种子贮藏蛋白积累的差异。结果表明,在子叶发育过程中,蛋白含量高（４５％ ）的“公交８０５９－３”比蛋白含量低（３５％ ）的“ＧＤ－１５１５”蛋白含量高,且增长速率较快;蛋白质及７Ｓ和１１Ｓ亚基积累的时期较早,尤其是７Ｓ的β亚基。电镜观察表明“公交８０５９－３”蛋白质在液泡中的积累,前期与“ＧＤ１５１５”相似,中期以后的液泡中,蛋白体占整个细胞的比例均高于“ＧＤ１５１５”。这表明：大豆蛋白含量的差异有其生化及结构上的基础     

THE ASSOCIATION OF DRUSE CRYSTALS WITH THE DEVELOPING STOMIUM OF CAPSICUM ANNUUM (SOLANACEAE) ANTHERS

Each of the two stomiums in the anther of Capsicum annuum (sweet pepper) consists of a single layer of cells immediately below the epidermis between two adjacent locules. Each stomium extends the entire length of the anther and splits open at pollen maturity. Many calcium oxalate druse crystals form within the vacuoles of the stomium cells in association with membrane complexes and paracrystalline bodies. These latter structures are reported here for the first time and each is considered to be a nucleation site for druse crystal formation. Prior to the appearance of membrane complexes and crystals within the vacuoles, plasmalemmasomes are visible next to the stomium cell walls and contain vesicles and fibrous material. We propose that these bodies carry wall materials, including calcium ions and possibly oxalate ions, into the vacuoles. Their presence coincides with crystal formation. Two other types of crystals occur in the connective tissue between stomiums and the single vascular strand. These crystals, along with those in the two stomiums, form at precise times during anther development. Contrary to the more numerous suggestions that crystals protect against predators or are metabolic waste products, we believe their formation aids in degradation and weakening of the cell walls between the locules and, thus, contributes to the release mechanism for the pollen.     

A STUDY OF THE RELIABILITY OF SYNCHRONY IN THE DEVELOPMENT OF POLLEN MOTHER CELLS OF LILIUM LONGIFLORUM AT THE FIRST MEIOTIC PROPHASE

Lilium longiflorum anthers have been used by a number of investigators as a source of supposedly synchronous cells for studying genetic, chromosomal and molecular events of meiotic prophase I. Because of questions raised by the literature as to the reliability of such synchrony, new baseline data were obtained for L. longiflorum ‘Croft’ in preparation for experiments requiring homogeneity or synchrony. Homogeneity was found to be reliable at the same level of locules of the same anther and of anthers from the same bud up to the onset of diplotene. Synchrony deteriorates rapidly from diplotene on. Less than half the anthers examined had PMC's at the same stage from apex to base. Hence experiments requiring complete homogeneity within anthers would call for rigorous monitoring of each anther included in the sample. Synchrony between buds of the same length was insufficient to allow bud length to be used as a reliable index of meiotic stage.