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1.
Oat leaf base: tissue with an efficient regeneration capacity 总被引:1,自引:1,他引:0
Summary An efficient short term regeneration system using seedling derived oat (Avena sativa) leaf tissue has been developed. Callus derived from the leaf base showed a higher response of plant regeneration than callus initiated from mesocotyls and more mature parts of the leaves. A correlation between the nuclear DNA content of the donor material, as analysed with flow cytometry, and its ability to form callus was observed. Somatic embryogenesis was histologically recognised from callus derived from tissue close to the apical meristem. Plant regeneration media with various concentrations of auxin were tested. Callus from three different cultivars had a similar regeneration potential with an optimal regeneration frequency of 60%. About 2 months after inoculation regenerated plantlets could be moved to a greenhouse for cultivation.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- DAPI
6-diamidino-2-phenylindole
- IAA
indole-3-acetic acid
- KT
kinetin
- MS
Murashige and Skoog's medium
- NAA
naphthalene acetic acid 相似文献
2.
Ronghua Zhuge Siben Li Ter-Hsin Chen Walter H. Hsu 《Molecular reproduction and development》1995,41(1):20-28
This study investigated the underlying mechanisms of oxytocin (OT)-induced increases in intracellular Ca2+ concentrations ([Ca2+]i) in acutely dispersed myometrial cells from prepartum sows. A dosedependent increase in [Ca2+]i was induced by OT (0.1 nM to 1 μM) in the presence and absence of extracellular Ca2+ ([Ca2+]e). [Ca2+]i was elevated by OT in a biphasic pattern, with a spike followed by a sustained plateau in the presence of [Ca2+]e. However, in the absence of [Ca2+]e, the [Ca2+]i response to OT became monophasic with a lower amplitude and no plateau, and this monophasic increase was abolished by pretreatment with ionomycin, a Ca2+ ionophore. Administration of OT (1 μM) for 15 sec increased inositol 1,4,5-trisphosphate (IP3) formation by 61%. Pretreatment with pertussis toxin (PTX, 1 μg/ml) for 2 hr failed to alter the OT-induced increase in [Ca2+]i and IP3 formation. U-73122 (30 nM to 3 μM), a phospholipase C (PLC) inhibitor, depressed the rise in [Ca2+]i by OT dose dependently. U-73122 (3 μM) also abolished the OT-induced IP3 formation. Thapsigargin (2 μM), an inhibitor of Ca2+-ATPase in the endoplasmic reticulum, did not increase [Ca2+]i. However, it did time-dependently inhibit the OT-induced increase in [Ca2+]i. Nimodipine (1 μM), a Voltage-dependent Ca2+ channel (VDCC) blocker, inhibited the OT-induced plateau by 26%. La3+ (1 μM), a nonspecific Ca2+ channel blocker, abrogated the OT-induced plateau. In whole-cell patch-clamp studies used to evaluate VDCC activities, OT (0.1 μM) increased Ca2+ Current (Ica) by 40% with no apparent changes in the current-voltage relationship. The OT-induced increase in Ica reached the maximum in 5 min, and the increase was abolished by nimodipine (1 μM). These results suggested that (1) activation of OT receptors in porcine myometrium evokes a cascade in the PTX-insensitive G-protein–PLC-IP3 signal transduction, resulting in an increase in [Ca2+]i; (2) the OT-induced increase in [Ca2+]i is characterized by a biphasic pattern, in which the spike is predominately contributed by the intracellular Ca2+ release from the IP3-sensitive pool, and to a lesser extent by Ca2+ influx, whereas the plateau is from increased Ca2+ influx; and (3) the influx is via VDCC and receptor-operated Ca2+ channels. © 1995 Wiley-Liss, Inc. 相似文献
3.
人肝刺激因子对大鼠实验性慢性肝损伤的保护作用 总被引:3,自引:0,他引:3
从健康孕妇水囊引产4─6个月龄的胎儿取肝,采用LaBrecque方法提取人肝刺激因子(hHSS)。经3H-胸腺嘧啶核苷参入肝DNA法测定其生物活性。表明此hHSS可刺激肝细胞DNA合成。采用皮下注射CCl4和饮用10%乙醇来制备慢性肝损伤动物模型,观察了hHSS的保护肝脏作用。结果表明:hHSS可使CCl4-乙醇所致慢性肝损伤大鼠的死亡率、血清谷丙转氨酶水平、肝组织中羟脯氨酸含量的升高以及肝组织中丙二醛的含量降低。肝组织切片表明:hHSS能减轻肝组织的损伤程度,促进肝细胞再生,并能明显防止肝纤维化的形成和发展。可见,hHSS对CCl4-乙醇所致的慢性肝损伤大鼠有明显的保护作用,其机制可能与促进肝细胞再生及抑制肝细胞膜的脂质过氧化有关。 相似文献
4.
周荣华 《中国科学:生命科学英文版》1997,40(6):657-664
Using genomicin-situ hybridization (GISH) technique, 7 translocation-addition lines, 6 translocation and translocation-addition lines, 2 ditelosomic
addition lines and 1 translocation line were identified fromTriticum aestivum L. -Psathyrostachys juncea (Fisch.) Nevski intergeneric hybrids, of which translocation-addition and translocation and translocation-addition lines
were not found in other reports. No substitutions and disornic additions were detected in the, hybrids and breakages occurred
in allP. juncea chromosomes studied. Results have shown that the improved GISH technique is a rapid and economical method for use in this
field. 相似文献
5.
脲酶抑制剂氢醌的环境效应评价 总被引:5,自引:0,他引:5
本文根据用标记和非标记氢醌进行的模拟、盆栽和田间定位试验,结合国内外文献有关氢醌的环境常数,论述了氢醌在土壤-植物系统的去向和代谢途径、对土壤酶活性的影响及其环境效应。得出的结论是:作为脲酶抑制剂使用的微量氢醌(0.3—0.4%,与尿素重量比),不会从土壤中淋失和挥发,在土壤和植物中没有累积,对与碳、氮和磷转化有关的土壤酶活性很少影响。在土壤中,它将通过氧化、臭氧化和生物学降解,经由环断裂生成二元酸或参与腐殖物质的合成。在植物体内,主要通过糖苷化得到同化和利用。因此,氢醌作为脲酶抑制剂在农业生产中应用是安全的。 相似文献
6.
微生物来源的酶抑制剂研究进展 总被引:4,自引:1,他引:4
1958年,植物学家Kohland首先提出次生代谢的概念,1960年Bu’Lock把这一概念引进微生物学领域。微生物次生代谢物包括抗生素、色素、毒素、信息素、动植物生长促进剂和生物药物素(biopharmaceutin)等。其中生物药物素包括酶抑制... 相似文献
7.
用基因组原位杂交与RFLP标记鉴定小麦——簇毛麦抗白粉病代换系 总被引:27,自引:3,他引:27
用荧光素标记的簇毛麦(Haynaldia villosa)基因组总DNA作探针,以普通小麦基因组总DNA作封阻,与花粉母细胞减数分裂中期Ⅰ制片的染色体进行原位杂交。结果表明,抗白粉病小麦品系GN22是普通小麦-簇毛麦二体代换系;用已定位在小麦第6部分同源群上的RFLP探针psr113、psr371进行Southern分析,进一步证明,小麦品系GN21、GN22是普通小麦-簇毛麦6A(6V)代换系;结合同工酶等电聚焦电泳分析,首次把簇毛麦编码的α-淀粉酶-1生化位点定位在簇毛麦6V染色体长臂上,暂命名为α-Amy-Ⅴ1。研究结果表明,原位杂交与RFLP技术相结合是全面、准确鉴定小麦外源染色体及其与小麦染色体部分同源关系的有效方法。 相似文献
8.
白腐菌对染料脱色和降解作用的研究进展 总被引:2,自引:0,他引:2
白腐菌应用于废水处理始于二十世纪八十年代。本文对印染废水的处理方法、白腐菌及其对污染物的降解机理作了简要概述 ,着重介绍了白腐菌对染料脱色和降解作用的研究进展。白腐菌对染料的脱色解降作用机理有部分尚待进一步研究 ;同时 ,白腐菌的吸附作用亦不容忽视。 相似文献
9.
植物叶绿素含量与大气中SO2浓度相关性研究 总被引:1,自引:0,他引:1
本文对厦门市5个样点、6种常见绿化树种及盆栽植物蕹菜的叶绿素含量、叶片含硫量及大气中SO_2浓度分析测定,得出了6种植物叶绿素a、b变化趋势是:鼓浪屿、厦门大学>火车站、后江埭>电化厂;叶片含硫量的变化趋势与叶绿素a、b含量变化相反。表明植物叶片叶绿素含量与大气中SO_2浓度和叶片含硫量呈负相关,并计算蕹菜叶绿素含量与大气SO_2浓度相关模式(y=-0.0138x 0.1958),为大气环境评价提供生物学依据。 相似文献
10.