枣树人工种子的研制

枣树 (Ziziphusjujuba)枝条扦插极难生根 ,树体上能作接穗的枣头又少 ,加快枣树繁殖一直是枣树生产中一项亟待解决的问题。近年来 ,以枣树茎段培养进行苗木快速繁殖 (张福泉 ,1983;刘仁贵 ,1988;罗晓芳等 ,1996 ;刘翠云等 ,1997)和苗木脱毒 (田砚亭等 ,1993)的研究报道较多 ,但     

粗毛淫羊藿幼叶愈伤组织的生产

应用正交设计法考察4种激素对粗毛淫羊藿(Epimedium acuminatum Francn.)叶片诱导愈伤组织的影响.得出IBA作用极显著,2,4-D作用显著,6-BA、NAA作用不显著,它们作用大小依次为:IBA＞2,4-D＞6-BA＞NAA.诱导粗毛淫羊藿愈伤组织产生的最佳激素配比为:B5 2,4-D 2 mg/L IBA 1 mg/L.     

Identification of microbial communities that assimilate substrate from root cap cells in an aerobic soil using a DNA-SIP approach

Although root cap cells are an important substrate for microorganisms in the rhizosphere, little attention has been paid to the decomposition of sloughed root cap cells by microorganisms. This study used rice plant callus cells grown on medium containing ¹³C-labelled glucose as a model material for rice plant root cap cells. Harvested ¹³C-labelled callus cells (78 atom % ¹³C) were subjected to decomposition in an aerobic soil microcosm for 56 days. The low cellulose and lignin levels and the disaggregated nature of the callus cells indicated that these cells were an appropriate model material for root cap cells. DNA was extracted from a soil incubated with ¹²C- and ¹³C-callus cells and subjected to buoyant density gradient centrifugation to identify bacterial species that assimilated carbon from the callus cells. The stability of the total bacterial communities during the incubation was estimated. Many DGGE bands in light fractions of soil incubated with ¹³C-callus cells were weaker in intensity than those from soil incubated with ¹²C-callus cells, and those bands were shifted to heavier fractions after ¹³C-callus treatment. ¹³C-labelled DNA was detected from Day 3 onwards, and the DGGE bands in the heavy fractions were most numerous on Day 21. DGGE bands from heavy and light fractions were sequenced, revealing more than 70% of callus- C incorporating bacteria were Gram-negative, predominantly α-Proteobacteria, β-Proteobacteria, γ-Proteobacteria, Sphingobacteria and Actinobacteria. These species were phylogenetically distinct from the bacteria reported to be present during plant residue decomposition and resident in rice roots. This study indicates that root cap cells are decomposed by specific bacterial species in the rhizosphere, and that these species augment the diversity of rhizospheric bacterial communities.     

培养基碳源对桑茎尖愈伤组织诱导的影响

培养基中的碳源是植物离体培养的重要养分之一。为逐渐完善桑树愈伤组织培养与植株再生试验体系,以桑品种育71-1的茎尖为材料,采用MS培养基为基础培养基,分别添加不同浓度的葡萄糖、蔗糖、麦芽糖作为碳源,研究不同种类及不同浓度碳源对桑茎尖愈伤组织诱导的影响。试验结果表明:对桑茎尖愈伤组织诱导效果最佳的碳源是葡萄糖,其次是蔗糖和麦芽糖;葡萄糖和蔗糖的浓度对于愈伤组织的诱导有显著影响,而麦芽糖的浓度影响不显著,3种碳源的添加量为4%(质量分数)时,愈伤组织的形成率和生长量最大。依据试验结果认为,用育71-1桑树茎尖为外植体诱导愈伤组织,以质量分数为4%的葡萄糖作为培养基碳源的效果最佳。     

Adventitious shoot regeneration from leaf thin cell layers in apple

The present investigation was conducted to study organogenesis of a conventionally easy-to-regenerate (‘Royal Gala’) and a difficult-to-regenerate (‘Freedom’) apple cultivar using leaf transverse thin cell layers (tTCLs). The position of the leaf source, explant type and light regime applied to tTCLs were investigated as was their influence on the organogenic outcome. Light during the onset of regeneration delayed morphogenesis or, in ‘Freedom’, completely inhibited organogenesis on leaf tTCLs. Genotype and initial position of the leaf also influenced percentage regeneration and number of regenerated shoots per explant. This study demonstrates the successful application of leaf tTCLs for adventitious shoot regeneration in apple, even though further studies are needed to increase the number of shoots more than control explants. Shoot regeneration from apple leaf tTCLs serves as an alternative protocol for studying fundamental and applied aspects of regeneration.     

不同因子对翅果油树愈伤组织诱导及分化的影响

翅果油树的繁殖和保存是目前急需解决的问题。本试验选用试管芽苗上的叶片作为外植体, 研究不同因子对愈伤组织诱导及其分化的影响。结果表明: MS+BA1mg/L+2 .4 D1 5mg/L为最佳愈伤组织诱导培养基; 在愈伤组织诱导时, 光照条件以前期暗培养、后期光培养为宜, 温度以24℃~26℃为宜; 在诱导愈伤组织芽分化时,芽分化的培养基以MS+BA1mg/L+IBA0. 05mg/L最为合适, 温度以26℃左右为宜。     

稻瘟病菌及其粗毒素对水稻愈伤组织毒害的初探

稻瘟病菌用毒素对水稻愈伤组织具有毒害作用，表现为降低水稻愈伤组织的诱导率及生存率．稻瘟病菌孢子能在不同抗性的水稻愈伤组织上萌发定殖并侵染细胞．不同基因型水稻品种，不论抗性如何，其愈伤组织与稻瘟病菌都呈亲和性，没有专化性表现．在愈伤组织水平上以稻瘟病菌粗毒素为选择压筛选抗病个体，可能无效．     

青年奶山羊非繁殖季节诱发发情的研究

在奶山羊非繁殖季节的4～5月份,对293只青年羊进行了诱发发情试验。试验组用孕激素药管埋植6天或9天,分别注射PMSG(10,15,20IU/w·kg),母羊发情时注射HCG 1000IU/只或注射LRH—A100μg/只。试验羊在除去药管后进行1～2次配种。结果表明用孕激素预先处理并注射PMSG 15IU/kg·w组母羊的同期发情率为97.6％(P<0.01);第一情期受胎率为78.3％(P<0.05);第一情期配种受胎分娩率为53％。     

EMS诱变小麦愈伤组织选择抗旱突变体的研究

以抗旱性差的小麦品种温麦6号和周麦17的花药愈伤组织和幼胚愈伤组织为材料,进行 EMS诱变处理,结果表明:EMS溶液处理花药愈伤组织相对分化率近50％的浓度和时间组合为 0．20％ (2-6h);处理幼胚愈伤组织相对分化率近50％的浓度和时间组合为(0．20％-0．40％) (2-4h)。 将EMS诱变处理后分化的224株再生植株接种到PEG浓度为80g/L的生根培养基中,进行抗旱筛 选,共得到13株抗旱植株,平均变异率为5．8％。花药愈伤组织和幼胚愈伤组织EMS溶液诱变处理的 适宜浓度和时间组合为0．20％ 4h。     

非洲菊花瓣的离体培养

试验以不同花色非洲菊的花瓣为材料 ,在添加不同浓度的 2 ,4-D和 6-BA的培养基上进行愈伤组织诱导和芽的分化。结果表明 :不同花色愈伤组织的诱导率存在差别 ;不同浓度的 2 ,4-D和BA对愈伤组织的诱导和分化的效果明显不同 ,2 ,4-D和BA浓度过高对诱导和分化均有抑制作用 ;诱导花瓣形成愈伤组织的最佳培养基为MS +2 ,4-D 2 .0mg/L +NAA 0 .2mg/L +BA0 .1mg/L ,花瓣不定芽分化的最佳培养基为MS +BA 8.0mg/L +NAA 0 .1mg/L。