Rhizogenesis of GF677, Early Crest,May Crest and Arm King stem cuttings during the year in relation to carbohydrate and natural hormone content

The rhizogenesis of GF677, Early Crest, May Crest and Arm King stem cuttings during the year was investigated. The results showed significant differences in the rooting percentage between different dates of cutting collection and also between the four cultivars. Among these, GF677 generally had the highest rooting percentage. Rooting of cuttings was high in October, November and February and relatively low in the periods March–September and December–January. Interactions among cultivars were also found.     

四种杀菌剂对金银花白粉病的防治效果及对金银花品质的影响

采用随机区组试验比较四种杀菌剂对金银花白粉病的防治效果，用高效液相色谱法测定各处理样品的绿原酸含量，以筛选出符合金银花规范化种植需要的药剂。结果表明，施药后14天以15％三唑酮600倍液防治效果最好，达77．8％，其次是15％三唑酮1200倍、50％多菌灵500倍液处理，防治效果分别为75．7％和70．8％，极显著地高于3％中生菌素500和1000倍及2％农抗1201000倍液处理的防效。2％农抗120500倍液的防治效果达60．3％，与前三种处理差异不显著，显著好于后三种处理，但未达极显著水平。15％三唑酮1200倍防治处理的绿原酸含量最高，达1．683％，其次是50％多菌灵500倍处理，绿原酸含量达1．539％，符合《中华人民共和国药典》要求，可作为金银花规范化管理中白粉病防治优先采用的药剂。     

大枣加工中氧化型维生素C和还原型维生素C的变化

以大枣为原料,在浸提、澄清工序中,通过抗氧化剂和果胶酶处理试验,旨在探索大枣在加工过程中氧化型维生素C和还原型维生素C的变化规律,达到最大限度保存大枣中总维生素C的目的。结果表明,(1)采用植酸处理对还原型维生素C的保存效果最好;(2)0.04%的六偏磷酸钠和0.06%的EDTA-2Na对氧化型维生素C和还原型维生素C都具有较好地保存作用;(3)茶多酚和EDTA-2Na对氧化型维生素C的降解起抑制作用;(4)六偏磷酸钠可使氧化型维生素C和总维生素C的含量增高;⑤采用果胶酶处理对氧化型维生素C具有较好地保存作用。     

苹果砧木SH40 和八棱海棠缺铁胁迫下根系有机酸分泌的差异

 以苹果砧木SH₄₀和八棱海棠(Malus micromalus) 的生根试管苗为试材, 采用水培方法, 研究了缺铁胁迫对根系分泌有机酸的种类和数量的影响。结果表明: SH40和八棱海棠根系分泌有机酸种类相同,主要是草酸、丙二酸、酒石酸、苹果酸和柠檬酸, 但在分泌总量上差异明显, 八棱海棠分泌有机酸总量大于SH₄₀。缺铁胁迫时SH₄₀草酸分泌量和八棱海棠柠檬酸分泌量大量增加, 且八棱海棠干物质和铁含量明显高于SH₄₀。草酸和柠檬酸分泌量增加可能是SH₄₀和八棱海棠耐受缺铁胁迫的原因之一。     

Uncoupling and inhibition properties of 3,4-seco-friedelan-3-oic acid isolated from Maytenus imbricata

3,4-Seco-friedelan-3-oic acid was isolated from Maytenus imbricata (Celastraceae). At low concentrations it inhibited non-cyclic electron transport and ATP synthesis in spinach chloroplasts, i.e., it behaved as a Hill reaction inhibitor, and at high concentrations it acts as an uncoupler by enhancing uncoupled electron transport and Mg²⁺-ATPase activity. 3,4-Seco-friedelan-3-oic acid did not inhibit PSII electron transport from DPC to DCPIP_ox and photosystem I activity, but it enhanced from TMQH₂ to MV, corroborating its action as uncoupler. It inhibits electron flow through PSII from water to sodium silicomolybdate. The whole results indicate that the 3,4-seco-friedelan-3-oic acid target is at the OEC complex enzyme, the donor side of PSII. The fluorescence decay data shows the formation of the K-band, which match this result, acting as inhibitor at the donor side of PSII and it as an uncoupler.     

牦牛肉中游离氨基酸含量的分析

采用反相高效液相色谱法测定了7头麦洼牦牛后腿肌肉中游离氨基酸的舍量。在牦牛肉中检测到16种游离的标准氨基酸，总含量为532．34±86．74mg／100g，其中含量最高的游离氨基酸为精氨酸，其次为组氨酸，这两种氨基酸约占游离氨基酸总量的75％。     

青海微孔草经济价值及开发利用前景

微孔草是一种野生珍稀油料植物。本文通过对青海微孔草生物学特性及分布、生态学特性及经济价值的分析,指出微孔草富含r-亚麻酸,具有较高的营养价值和保健价值,并对微孔草的开发利用前景进行了分析。     

鹅黑素皮质素受体-4基因的克隆与序列分析

黑素皮质素受体-4（Melanocortin receptor-4,MC4R）是其黑素皮质素受体MCR（MC1-5R）家族成员之一,属G蛋白偶联受体。它可与瘦蛋白、神经肽、α-黑素细胞刺激素等一起调节动物体重和采食量。参考鸡MC4R基因序列设计引物,克隆并测序了鹅MC4R基因。结果表明,鹅MC4R基因编码区全长996 bp,其核苷酸序列与鸡的同源性为95.3%,与人、牛、猪等哺乳动物同源性在75%-79%;其氨基酸序列与鸡的同源性达到98.5%。构建哺乳类、鸟类和鱼类MC4R基因核苷酸进化树显示,鹅较早地与哺乳类动物分化开来。分析MC4R蛋白的氨基酸残基特性参数表明,MC4R的7次跨膜结构与MC4R的亲水性区域、电荷密度以及氨基酸残基位于表面概率的变化规律相一致。     

High frequency plantlet regeneration from callus and artificial seed production of rock plant Pogonatherum paniceum (Lam.) Hack. (Poaceae)

Pogonatherum paniceum (Lam.) Hack. is a rock plant with good potential for vegetative recovery on naked lands. A high frequency in vitro regeneration system was developed for P. paniceum. Calli were induced from explants of mature seeds, seedlings, young leaves, and stem segments on Murashige and Skoog (MS) medium supplemented with 1.0 mg L⁻¹ 2,4-dichlorophenoxyacetic acid (2,4-D), 2.0 mg L⁻¹ α-naphthalene acetic acid (NAA) and 0.2 mg L⁻¹ 6-benzylaminopurine (BAP). High induction rates (59.57%) and regeneration rates (100%) were obtained from mature seed explants; calli were sub-cultured for over 2 years and still retained a high regenerative capacity. One seed explant resulted in 69,997 plants in 1 year. Shoot buds derived from calli were used for encapsulation in liquid MS medium containing 3% sucrose and two different alginate matrices (3% sodium alginate (w/v) + MS medium containing 3% sucrose and 3% sodium alginate + 1% activated carbon (w/v) + MS medium containing 3% sucrose) with a 20-min exposure to 2% CaCl₂ and 0.3% bavistin (w/v). The capsule with 3.0% sodium alginate (w/v) and 1% activated carbon (w/v) showed a higher conversion rate (61.58%) and stronger plantlets under non-aseptic conditions. These systems are useful for the rapid clonal propagation and dissemination of artificial seed material of P. paniceum for eco-recovery.     

Cryopreservation of carnation (Dianthus caryophyllus L.) shoot tips by encapsulation-vitrification

Shoot tips excised from in vitro cultured plants of Dianthus caryophyllus L. (cv. Pallas, cv. Pink Candy and cv. Wanessa) were successfully cryopreserved using an encapsulation-vitrification method. Shoot tips (2–3 mm in length) were encapsulated in sodium alginate, precultured on liquid Murashige and Skoog (1962) medium supplemented with various sucrose concentrations (0.25, 0.5, 0.75, 1.0 M) for 24 h or 48 h and dehydrated with the vitrification solution PVS2 (up to 4 h) at 24 °C or 0 °C prior to direct immersion in liquid nitrogen (−196 °C). A maximum of shoot regeneration from cryopreserved shoot tips was obtained with the following combinations: preculture in 0.5 M sucrose and 180 min dehydration treatment at 0 °C for cv. Pallas (60% shoot formation), or preculture in 0.75 M and 200 min dehydration at the same temperature for cv. Pink Candy (66.6% shoot formation) and cv. Wanessa (73% shoot formation).