Two-step one-dimensional SDS-PAGE analysis of LMW subunits of glutelin

Summary Analysis of intergeneric substitution lines in hexaploid wheats by a two-step electrophoretic method of protein separation revealed that low-molecular-weight (LMW) subunits of glutelin in Triticum longissimum, T. Umbelullatum, Elytrigia elongata (2 x) were controlled by chromosomes/chromosome arms 1S ^l , 1U, and 1ES, respectively. A LMW glutelin band in Secale montanum was detected but its chromosomal location could not be determined. Genes controlling gliadins and HMW subunits of glutelin were also located on chromosome 1S ^l in T. longissimum.The term glutelin refers to the polymeric prolamins of cereals, e.g., glutenins in wheat, HMW, and 75-k secalins in rye     

Changes in abscisic acid and indole-3-acetic acid in axillary buds of Elytrigia repens released from apical dominance

Growth of axillary buds on the rhizomes of Elytrigia repens (L) Nevski is strongly dominated by the rhizome apex, by mechanisms which may involve endogenous hormones. We determined the distribution of indole-3-acetic acid (IAA) and abscisic acid (ABA) in rhizomes and measured (by gas-chromatography-mass spectrometry) their content in axillary buds after rhizomes were decapitated. The same measurements were also made in buds induced to sprout by removing their subtending scale leaves. The ABA content tended to be higher in the apical bud and in the axillary buds than in the adjacent internodes, and tended to decline basipetally in the internodes and scale leaves. IAA was similary distributed, except that there was less difference between the buds and other rhizome parts. After rhizomes were decapitated, the ABA content of the first axillary bud declined to 20% of that of control values within 24 h, while the IAA content showed no marked tendency to change. The ABA content also declined within 12 h in the first axillary bud after rhizomes were denuded, while the content of IAA tended to increase after 6 h. These changes occurred before the length of the first axillary bud increased 24–48 h after rhizomes were decapitated or denuded. We conclude that the release of axillary buds from apical dominance in E. repens does not require IAA content to be reduced, but is associated with reduced ABA content.     

八倍体小偃麦染色体组分析

本文对普通小麦与长穗偃麦草(Elytrigia elongata=Agropyron elongatum.2n=70)杂交选育出来的5个八倍体小偃麦的染色体组进行了研究。通过八倍体小偃麦与普通小麦杂交,八倍体小偃麦相互间杂交,观察了杂种F_1花粉母细胞减数分裂行为。根据观察结果,讨论了长穗偃麦草染色体组的构成,认为长穗偃麦草的染色体组为E_1E_2F_2F_2N较为合适。在此基础上,确定了5个八倍体小偃麦的染色体组:7430为ABDE_1,68为ABDF_1,693为ABDF_1,7631为ABDF_2,784为ABDN。另外,还讨论了八倍体小偃麦染色组的重组问题。     

新疆多年生小麦族植物染色体数的观察

本文对1987年采集于新疆的多年生小麦族(Triticeae Dum. )属种进行了细胞学观察。该地区多年生小麦族各属种的染色体数目变化范围是从2n=14到2n=84,前者主要存在于大麦属(Hordeum)、新麦草属(Psathyrostachys),而后者全部集中于赖草属(Leymus).其中染色体数目为2n=28和2n=42的频率最高,主要存在于鹅冠草属(Roegneria)和披碱草属(Elymus)。Roegneria gobicola, Roegneria kuqaensis, Roegneria tahelacona, Roegneria zhoasuensis的染色体数为首次报道。     

Vigor and salt tolerance in 3 lines of tall wheatgrass

The F₁ progeny of the cross of two salt-tolerant lines of Thinopyrum elongatum [Host] D. R. Dewey grew better than either parent under non-saline and saline growth conditions. Under non-saline conditions, the hybrid produced 1.8 times as much vegetative tissue as one parent and 3.2 times more than the other parent in the same length of time. The relative growth rates of the 2 parental lines decreased equally as media osmotic potentials decreased. The relative growth rate of the hybrid did not decrease as rapidly as that of the parents; therefore, it was concluded that the greater growth of the hybrid was due to increased salt tolerance. Carbohydrate reserves and water-soluble solutes believed to be involved in osmotic adjustment were assayed to determine if there were any differences between the hybrid and its parents in their abilities to accumulate these compounds. The concentrations of these constituents were measured at dawn and at dusk of the same day in plants grown in media at osmotic potentials ranging from –0.1 to –1.2 MPa. There were no differences in pool sizes of the organic compounds in the 3 lines. Starch increased 10–40 fold in leaves from dawn to dusk and sucrose increased 100-fold. However, this pattern was unaffected by salinity. Conversely, betaine concentrations increased with increasing salinity but were the same at dawn and dusk. Na⁺ and K⁺ were affected by both light and salinity. Cl was one-half (Na⁺+ K⁺) on a molar basis under all conditions. Proline accumulated when (Na⁺+ K⁺) exceeded 200 μmol (g fresh weight)^?1. Since this amount of (Na⁺+ K⁺) existed only in tissues harvested at dusk from severely saline-stressed plants, only leaves from such plants harvested at dusk contained proline.     

厌氧细菌Acetanaerobacterium elongatum从葡萄糖的产氢特性研究

为了了解影响厌氧发酵产氢细菌Acetanaerobacterium elongatumZ7产氢效率的因素,采用生理学方法对其进行了研究。结果表明:乙醇型发酵菌A.elongatumZ7的最适产氢温度为37℃,最适产氢的起始pH为8.0。该菌发酵葡萄糖和阿拉伯糖产氢的能力较强,氢气产率分别为1.55mol H2/mol葡萄糖和1.50mol H2/mol阿拉伯糖。酵母粉是菌株Z7生长和产氢所必须的生长因子;pH影响菌株的生长和葡萄糖利用率;氢压则影响电子流的分配,从而改变代谢产物乙酸和乙醇的比例;当产氢菌与甲烷菌共培养以维持发酵体系低的氢压时,可使氢的理论产量提高约4倍;培养基中乙酸钠浓度>60mmol/L明显抑制产氢。另外,一个只利用蛋白类物质的细菌能够促进菌株Z7对葡萄糖的利用,进而提供氢产量,为生物制氢的工业化生产提供理论参考。     

长穗偃麦草酸性磷酸酶与碱性磷酸酶编码基因的染色体定位

以一套中国春-长穗偃麦草二体异附加系与二体异代换系为材料,用等电聚焦(IEF)研究长穗偃麦草基因组中酸性磷酸酶(AcPh)与碱性磷酸酶(APH)编码基因的染色体定位。结果表明,AcPh大多聚焦于pH5～7范围内,其编码基因位于3E染色体,而APH编码基因则位于4E染色体。由于5E染色体的附加,AcPh活性带强度显著减弱。     

长穗偃麦草基因组中与耐低磷营养胁迫有关的基因的染色体定位

以中国春－长穗偃麦草二体异附加系和二体异代换系为材料，对其耐低磷营养胁迫特性进行鉴定和遗传分析，结果表明（１）长穗偃麦草的４Ｅ一＾ 色体携有耐低营养胁迫的基因，且其效应远远超过背景亲本中国春。     

（普通小麦／长穗偃麦草）F1小孢子发生和雄配子体发育的细胞学特点

试验用压片法对（普通小麦／长穗偃麦草）Ｆ１小孢子发生和雄配子体发育进行了细胞学观察．观察表明：１．（普通小麦／长穗偃麦草）Ｆ１花粉母细胞减数分裂过程中出现许多异常现象;在ＰＭＣ Ｍ１出现较高频率的单价体和多价体;但是减数分裂过程能够完成,并且四分孢子的败育率较低。２．在雄配子体发育过程中可观察到具有多微核、体积不等的小孢子,并发现经过对称孢子有丝分裂产生的二胞花粉;在花粉发育的不同时期均可观察到花     

偃麦草与小偃麦染色体组构成的细胞遗传学研究在Ⅴ.硬粒小麦与中间偃麦草杂交及回交的细胞遗传学研究

获得了硬粒小麦(2n=6x=28、AABB)与中间偃麦草(2n=6x=42、NNE_1E_1E_2E_2)杂种F_1及回交后代材料。统计分析杂种F_1及回交一代PMC MI染色体配对构型,认为中间偃麦草具较远缘的同亲关系(distant homologous)染色体组。由三价体出现频率分析,中间偃麦草不含小麦的B染色体组,建议用NE_1E_2为其染色体组公式。根据回交一代及其自交后代染色体数目,分析了六倍体小偃麦这一人工新物种的形成过程。