秋水仙素诱导蒙古黄芪多倍体的研究

以黄芪种子和带子叶的上胚为处理对象,用在培养基里添加不同浓度秋水仙素的方法,研究了秋水仙素不同浓度、不同处理时间对黄芪多倍体诱导的影响.结果表明,两种处理对象的诱导效果受秋水仙素浓度和处理时间两方面的影响.以成熟种子为处理对象,各种秋水仙素浓度和处理时间组合均可诱导出多倍体植株,但以秋水仙素浓度100mg/L,处理时间14d的组合加倍率最高,达13.3%;以带子叶的上胚为处理对象,从秋水仙素浓度50mg/L,处理时间7d开始有较低的加倍率,以秋水仙素浓度100mg/L处理时间7d的加倍效果最好,为10.9%.细胞染色体鉴定结果为:四倍体染色体数为2n=4x=32;而二倍体的染色体数为2n=2x=16.     

秋水仙素处理对黑麦根尖细胞的诱变效应

为了了解秋水仙素对根尖细胞的诱变效应,以黑麦为材料,应用不同浓度秋水仙素(0.5,1.0,1.5,2.0g/L)和不同处理时间(12,24,36,48,60 h)试验研究了黑麦根尖细胞有丝分裂指数和染色体加倍效应。结果表明,1.5 g/L的秋水仙素处理24 h黑麦根尖细胞有丝分裂指数达到最高值,为35.35%;随着秋水仙素浓度的增加,染色体加倍效果也在增加,但四倍体加倍效应明显高于八倍体,同时出现了染色体黏连,染色体落后,染色体桥和染色体多核等异常现象。     

湘西辣椒花药离体培养及其再生植株染色体数目的变异

利用辣椒花药诱导单倍体研究表明：NTH,MS培养基均能诱导产生愈伤组织和胚状体,但NTH培养基比MS培养基培养效果好,以NTH+6-BA 0.2mg/L+NAA 0.5mg/L+KT 1.2mg/L+AgNO₃ 5.0 mg/L为愈伤组织和胚状体诱导的适宜培养基。通过花药培养获得的辣椒植株中,具有丰富的倍性变异,经染色体计数鉴定,单倍体( n=12 )约14%,二倍体(2n=24 )约46%,四倍体(4n=48 ) 约4%,各种混倍体约36%.     

茼蒿同源四倍体的诱发与细胞学研究

本文通过对茼蒿(Chrysanthemun CoronariumL)的不同品种和杂种一代进行同源四倍体的诱发、鉴定、细胞遗传学研究.探讨蔬菜多倍体的人工诱导方法与效果,以及多倍体的形态特征和遗传特性.为蔬菜的多倍体育种提供理论依据,并选育出茼蒿四倍体新品种.试验材料以目前生产上推广的细叶茼蒿、大叶茼蒿与其前两者的杂种一代,分别用不同浓度的秋水仙素(C_(22)H_(25)O_6N+1(1/2)H_2O)和不同处理方法诱发染色体加倍,并从形态和细胞学上进行鉴定,筛选出同源四倍体,对其诱发四倍体的第一代作染色体行为分析和稳定性分析,从中选择优良单株套袋自交留种,期望选育出具有优良性状的四倍体新品种.     

水稻籼粳杂种四倍体的人工诱导

以一种极端类型籼粳亚种的二倍体杂种为材料,杂种幼穗的愈伤组织用秋水仙碱处理获得四倍体植株.幼穗在含不同浓度的2,4-D和KT的培养基上愈伤组织的诱导率不同,2,4-D为2.0mgL,KT为1.0mg/L,愈伤组织的诱导率最高,达55.6%.秋水仙碱在500mg/L的浓度加倍效果最高,达40%.同时比较分蘖期秧苗和萌发种子的诱导率,仍以愈伤组织的加倍效果最好.     

激素和添加物对蝴蝶兰组培快繁的影响

以蝴蝶兰人工授粉的果荚种胚和组培苗的叶片、茎尖为外植体,进行组织培养快速繁殖研究.结果表明,果荚种胚是最好的外植体材料,1个果荚可培育出上万个原球茎.种胚诱导原球茎最佳激素组合为:6-BA 0.3mg/L+NAA 0.2 mg/L;原球茎增殖最佳激素组合为:6-BA 0.5 mg/L+NAA 0.2 mg/L;2%蔗糖和10%香蕉泥可以显著促进原球茎增殖;原球茎分化最佳激素组合为:6-BA 1.0 mg/L+NAA 0.2 mg/L;诱导生根IBA 0.5mg/L最佳;炼苗后移栽苗成活率达95%以上.优化后的蝴蝶兰组织培养条件,可为蝴蝶兰快速繁殖工厂化生产提供参考.     

南天竹的离体培养研究

以南天竹茎段为材料,对不同消毒剂、消毒时间和内生菌抑制剂的消毒效果及诱导、增殖和生根培养基进行研究.结果表明:不同消毒剂消毒效果最佳时间为10min;消毒效果排序1g/L HgCl250mL/L NaClO220mL/L NaClO280mL/L NaClO2;适宜的诱导培养基为MS(murashige skoog培养基)+1mg/L 6-BA+0.1mg/L IBA+90mg/L青霉素+1 600mg/L Vc,诱导率达66.67%;MS+0.5mg/L 6-BA+0.05mg/L NAA是最适增殖配方,株高1.67cm,增殖系数2.63;最佳壮苗培养基为MS+0.01mg/L NAA+0.3mg/L 6-BA,株高2.17cm,增殖系数6.27;在微量元素减半的1/2MS+0.2mg/L NAA+0.2mg/L IBA+4g/L活性碳+30g/L蔗糖的液体培养基上生根率可达76.67%.     

凌风草组织培养体系的建立

以凌风草为材料,通过对该植株再生条件的优化,获得适宜凌风草愈伤组织再生的外植体材料和基本培养基,建立凌风草愈伤组织再生体系.试验结果表明:愈伤组织诱导的最适外植体为凌风草种子,最适基本培养基为MS培养基,最佳培养基为MS+2,4-D 3.0 mg/L+6-BA0.3 mg/L;愈伤组织分化的最佳培养基为MS+NAA0.1 mg/L+6-BA1.0 mg/L+KT2.0 mg/L;生根最佳培养基为MS+NAA0.2 mg/L+C 0.2 g/L.     

食用药百合组织培养及其多倍体诱导研究

对食用药百合进行了组织培养和多倍体诱导研究。以百合的鳞片和正在生长的茎尖作为外植体,采用MS培养基作为基本培养基,设置不同浓度激素研究组织培养快繁的最佳方法;在离体培养条件下,初步比较了不同浓度的秋水仙素处理百合的诱变效果。结果表明：在温度25±2℃,光照15h/d,光照强度2000lx,培养基中加蔗糖30g/L、琼脂8g/L、pH5.8培养条件下,鳞片诱导的最适培养基为MS＋6-BA1.5mg/L＋NAA0.2mg/L,茎尖不定芽诱导的最适培养基为MS＋6-BA1.5mg/L＋NAA0.1mg/L,生根的最适培养基为1/2MS＋KT0.1mg/L＋NAA0.2mg/L;0.05%的秋水仙素处理12h诱变效果最佳,诱变率高达40%。     

大叶醉鱼草快繁技术初探

以庐山野生植物大叶醉鱼草的茎段为材料,对芽、丛生芽及生根培养方面进行了初步的研究.结果表明:MS+6-BA 0.5 mg/L+NAA 0 mg/L的培养基适宜诱导醉鱼草茎段芽和丛生芽生长,MS+NAA 0.2 mg/L的培养基适宜醉鱼草茎段生根.     

水稻基因表达谱分析寡核苷酸芯片制备的研究

 首先有目的地搜集了50个水稻花序相关基因,进行了探针的设计、筛选及合成纯化,用点样仪以微阵列的形式将其点于醛基化的玻璃片上;将3个不同生长阶段的水稻花序材料的总RNA经荧光标记反转录后与寡核苷酸芯片进行杂交.用ScanArray3000对获得的表达谱进行扫描分析显示,芯片图像背景均匀,信号清晰.用ImaGene4.0软件对表达谱分析表明,候选基因在水稻花序3个不同发育阶段的材料中,表达水平有显著差异.为进一步进行水稻寡核苷酸芯片的制备及应用奠定了基础.     

Ethylene signaling in rice

Ethylene regulates many aspects of growth, development and responses to environmental stresses in plants. Its signaling pathway has been established in model dicotyledonous plant Arabidopsis. However, its roles and signal transduction in monocotyledous rice plant remain largely unknown. In this review, we summarize the current advances in rice ethylene signaling studies and compare these with the results from Arabidopsis and other plants. Most of the components homologous to those in Arabidopsis ethylene signaling pathway have been found in rice, including five ethylene receptors, OsEIN2, OsEIL1, and OsERFs. Rice ethylene receptors are functionally more divergent than that of Arabidopsis. OsEIN2 and OsEIL1 display limited roles in regulation of rice ethylene responses compared with their Arabidopsis orthologs. ERF-like proteins OsERF1 and OsEBP-89 appear to be involved in rice ethylene signaling. However, whether they are activated through OsEIN2 and OsEIL1-mediated pathway needs further studies. Given that rice uses ethylene to control many processes that do not exist in Arabidopsis, it seems that new components or new mechanisms may exist in rice ethylene signaling pathway.     

分子标记辅助选育含有抗稻瘟病基因和软米基因两系不育系水稻新品系

以"浦软粳S"为转育亲本,利用分子标记辅助常规育种技术成功培育出含有Pi9,Pita,Pib和Pigm稻瘟病抗性基因及软米基因(Wx~(mq)),同时表现柱头外露率高的两系不育系水稻新品系"2179S"."2179S"不育系茎秆粗壮,矮杆大穗,株高为63.8 cm,柱头外露率平均为60%.研究结果为今后培育具有稻瘟病抗性的优质两系杂交水稻新组合提供不育系亲本.     

优质稻株的农艺性状与稻米品质关系的研究

测定桂花香等4个优质稻品种的农艺性状和稻米品质,进行相关分析和通径分析。农艺性状中的穗枝梗数和穗总粒数、穗实粒数之间呈极显著正相关,成穗率与穗长之间,穗复枝数与穗总数数之间呈显著正相关,而有效穗数与茎宽之间,千粒重与穗复枝数、穗实粒数均呈显著负相关。稻米品质中的糙米率与精米率呈极显著正相关,精米率与整精米率、蛋白质之间均呈显著正相关。整精米率、碱消值与直链淀粉含量之间,垩白率与糙米率、蛋白质之间均呈显著负相关,精米率与垩白率之间呈极显著负相关。农艺性状与稻米品质之间不呈显著相关。单株生产力对蛋白质含量的直接影响是负值,而生产力对直链淀粉含量的影响是正值,直接影响比间接影响大。     

水分胁迫对水、旱稻幼苗POD活性的影响

以四种抗旱性不同的水、旱稻幼苗为材料,采用愈创木酚分光光度法测定了不同生长时期、水分胁迫以及水分胁迫处理后复水幼苗的POD活性,并与同样条件下水、早稻幼苗SOD活性变化进行比较。结果表明,不仅水、旱稻幼苗SOD活性在不同发育时期、不同水分条件发生有特定规律的变化,而且POD活性也具有类似或同步的变化,即抗旱性较强的旱稻品种在水分胁迫时POD活性上升幅度大于水稻,复水后旱稻POD活性下降的幅度也比水稻大.由于SOD和POD在生化功能上具有偶联作用以及实验结果的相似性.故可以认为,不同水分条件水、旱稻幼苗POD活性的变化和SOD一样能够反映品种间抗旱能力的差异.     

Transgenic rice homozygous lines expressing GNA showed enhanced resistance to rice brown planthopper

Mature seed-derived calli from two elite Chinese japonica rice (Oryza sativa L.) cultivars Eyi 105 and Ewan 5 were co-transformed with two plasmids, pWRG1515 and pRSSGNA1, containing the selectable marker hygromycin phosphotransferase gene (hpt), the reporter β-glucuronidase gene (gusA) and the snowdrop (Galanthus nivalis) lectin gene (gna) via particle bombardment. 61 independent transgenic rice plants were regenerated from 329 bombarded calli. 79% transgenic plants contained all the three genes, revealed by PCR/Southern blot analysis. Western blot analysis revealed that 36 out of 48 gna-containing transgenic plants expressed GNA (75%) at various levels with the highest expression being approximately 0.5% of total soluble protein. Genetic analysis confirmed Mendelian segregation of transgenes in progeny. From the R2 generations whose R1 parent plants showing 3:1 Mendelian segregation patterns, we identified five independent homozygous lines containing and expressing all the three transgenes. Insect bioassay and feeding tests showed that these homozygous lines had significant inhibition to rice brown planthopper (Nilaparvata lugens, BPH) by decreasing BPH survival and overall fecundity, retarding BPH development and declining BPH feeding. These BPH-resistant lines have been incorporated into rice insect resistance breeding program. This is the first report that homozygous transgenic rice lines expressing GNA, developed by genetic transformation and through genetic analysis-based selection, conferred enhanced resistance to BPH, one of the most damaging insect pests in rice.     

水稻与菰属间性状转移研究

通过花粉管通道法实现了水稻与菰属间的性状转移,获得了可遗传的转基因水稻种子,所获得的转菰基因后代性状变异深刻、类型丰富,多种数量性状改良明显,得到部分形态、生育及经济性状方面有价值的材料,这些材料可望填补水稻种质资源的一些空白,而且部分材料已在多抗、高产、优质种上初见成效。     

上海地区杂草稻与水稻籽实形态差异比较研究

近年来,随着稻田直播技术的推广,杂草稻对栽培稻的危害也越来越大,比较杂草稻与水稻籽实之间的形态差异,能够为进境检验检疫中杂草稻的鉴别提供技术参考.从上海郊区(县)稻田内采集了包括杂草稻和水稻的98份样品,定量地测定了这98份样品的籽粒长和粒宽、籽粒长宽比、小穗长、芒长及株高,并对籽粒的颜色进行了分级.基于以上数据,应用聚类分析,发现98份样品可以区别出3组,分别包括57、33和8份样品,结合落粒性、穗形、种皮颜色及成熟时间等性状,明确组1为杂草稻,组2为栽培稻组,组3为少量形态上介于杂草稻和栽培稻的样品.应用主成分分析和无度量多维标定这两种排序方法对98个样品进行分析,进一步展示了各样品间的形态差异特点.方差分析发现,上海地区的杂草稻在粒长、粒宽、粒长/宽和小穗长这4个指标均显著地大于水稻,但是两者在株高和芒长上没有显著差异.     

Obtaining transgenic rice resistant to rice fungal blast disease by controlled cell death strategy

The strategy of the two-component system,composed of Barnase and Barstar which encode RNase and a specific inhibitor to the RNase respectively, is adopted to obtain transgenic rice resistant to rice fungal blast disease. In this study, two chimeric promoters, induced by rice blast fungus pathogen (Magnaporthe grisea), are fused with Barnase respectively to construct two plant expression vectors, pWBNBS and pPBNBS together with the Barstar driven by CaMV 35S promoter. The resistance of the transgenic rice lines to rice blast fungus disease and rice blight disease are evaluated. The results show that (1) the expression of Barnase is induced in rice leaves when inoculated with the spores of Magnaporthe grisea; (2) the induced expression level of Barnase surpasses the level of Barstar, which elicits a similar hypersensitive response (HR) in the leaves, and the transgenic plant shows high resistance to the rice fungal blast disease; and (3) transgenic rice plants also show obvious resistance to rice bacterial blight disease. Taken together, these results suggest that the transgenic rice plants harboring this two-component system acquire relatively broad spectrum resistance against pathogens, especially high resistance to rice fungal pathogen.