风沙区水保优良灌木──杨柴的育苗技术

风沙区水保优良灌木──杨柴的育苗技术杨柴又名蒙古岩黄芪（ＨｅｄｙｓａｒｕｍｍｏｎｇｏｌｉｃｕｍＴｕｒｃｚ．）、踏郎、三花子等，为豆科小灌木，高１～２米；根蘖性强，常“一株成林”；抗干旱，耐沙埋，抗逆性强，是优良的固沙先锋树种。成熟的杨柴种子除可榨油外...     

Growth and development of Lilium longiflorum ‘Nellie White’ during bulb production under controlled environments : I. Effects of constant,variable and greenhouse day/night temperature regimes on scale and stem bulblets

One-year-old scale and stem bulblets of Lilium longiflorum Thunb. ‘Nellie White’ (Easter lily) were grown under constant and variable growth chamber conditions and greenhouse conditions to compare growth and development and bulb production. Eight temperatures regimes were established using the following: six growth chambers set to provide day/night temperature regimes of 30/26, 26/22, 22/18, 18/14, 14/10 and 10/6 °C; a seventh growth chamber (VAR) programmed to begin at 22/18 °C, then decline in three 4–5 week steps to 10/6 °C, and subsequently increase in three 4–5 week steps to 22/18 °C to simulate seasonal field temperatures in the coastal bulb production area of northern California and southern Oregon; and a double layer polyethylene greenhouse (GH) set to begin cooling at 22 °C and heating at 18 °C. Ten percent of the scale bulblets and 35% of the stem bulblets failed to develop shoots (“no-shows”). “No-shows” increased with increasing temperature with a significant number starting at 18/14 °C. The moderately high GH temperature also induced “no-shows”. Maximum basal bulb (the main planted bulb) weight occurred at 26/22 °C for both bulblet types. Scale bulblets not only produced heavier basal bulbs with a larger circumference than stem bulblets, but also produced heavier stem bulbs. Stem bulb formation and production was maximized in the range of 18/14–26/22 °C and in the GH for scale bulblets. Stem bulb production from stem bulblets did not differ from zero. Scale bulblets produced more basal and stem roots than the stem bulblets at the end of the early growth period, but there was no significant difference at the end of the study. Root fresh weight was greatest in the range of 14/10–18/14 °C and declined at higher or lower temperatures. The VAR and GH treatments had similar root weights to those at 18/14 °C. Shoot length was maximized at 22/18 °C for stem bulblets and in the GH and at 22/18 °C for scale bulblets. Stem plus leaf (shoot) fresh weight was not statistically different between bulblet types with the exception of an increased weight for stem bulblets grown at 22/18 °C. Scale bulblets in the GH had greater stem plus leaf weights than scale bulblets in the other temperature regimes. Shoot leaf number was highest in stem bulblets at 22/18 °C and in the GH. In these two temperature treatments, more leaves were produced by stem bulblets than scale bulblets. In all other treatments, there was no significant difference in leaf number. Bulblet type had no effect on number of flowers produced. Flower number was maximum in the range 10/6–22/18 °C, decreased at 26/22 °C and in the GH, and was absent at 30/26 °C. For bulb production, reduced flowering is desired since flowers are generally removed during the outdoor bulb production period. Meristem abortion, which also causes a desirable reduction in flowers, was greater in scale bulblets. It occurred at 26/22 °C and was greater at 30/26 °C. Scale bulbs produced the largest main bulbs, with a maximum yield at 26/22 °C.     

东方百合鳞茎冷藏解除休眠的养分代谢和酶活性变化

 以自繁的东方百合鳞茎为材料, 研究在2℃、5℃和8℃条件下, 鳞片中淀粉、可溶性总糖、还原糖含量和几种酶活性的变化。在8周的冷藏期内, 淀粉含量持续明显下降, 可溶性糖和还原糖含量增加, CAT、POD、SOD酶的活性在冷藏第1周下降极显著, 而α - 淀粉酶活性在第3周出现峰值, 自冷藏第4周后4种代谢酶活性均处于低水平。本试验中, 不同低温处理间的差异不大, 冷藏第7周后可解除休眠。     

兰州百合生产现状与效益分析

为了客观全面分析兰州百合的种植效益,对兰州百合种植基地生产现状进行实地调研,并应用考虑资金时间价值的动态评价方法,对兰州百合种植基地的经济效益进行分析。结果表明,近年来兰州百合种植效益总体良好,但由连作障碍引起的老产区与新产区种植效益差别非常明显,目前兰州百合价格具有一定的市场风险承受能力。围绕种植效益提升,结合生产中存在的主要问题,提出了防止种植规模盲目扩张、减轻连作障碍、建立商品化良种繁育基地等生产建议。     

侵染观赏百合的黄瓜花叶病毒提纯和抗血清制备

采用PEG沉淀并结合差速离心技术,获得了精提纯的侵染观赏百合的黄瓜花叶病毒(CMV-Li).提纯病毒具有典型的核蛋白吸收峰曲线.OD260 nm/OD280 nm=1.236.将提纯病毒免疫兔子制备得CMV-Li抗血清.经微量沉淀法和间接ELISA法测定,其效价分别为1∶1024、1∶4096.两种方法相比,间接ELISA具有灵敏度高、特异反应强等优点.     

睡莲不同杂交组合幼胚愈伤组织诱导研究

以睡莲3个杂交组合的幼胚为外植体,研究了胚龄、基本培养基、植物生长调节剂配比对愈伤组织诱导的影响。结果表明:1/2MS为最适的基本培养基;3个杂交组合在1/2MS+2,4-D 2.0 mg/L+6-BA 2.0 mg/L培养基中愈伤组织的平均诱导率均最高,分别为56.4%、21.5%和47.9%;授粉后13~18 d为幼胚培养的最佳时期。     

东方百合设施栽培关键技术

根据辽宁果树良种繁殖场栽培西伯利亚和索邦2个百合品种的经验,从种球消毒、水肥管理、温湿度控制、养球和主要病虫害防治等方面,介绍东方百合设施栽培关键技术,为百合生产提供借鉴。     

水杨酸和山梨酸对百合切花的保鲜效果研究

用含有水杨酸和山梨酸的保鲜液对百合切花保鲜,结果表明,含有水杨酸和山梨酸的保鲜液都能增加百合切花的鲜重,维持较长时期的水分平衡,促进花朵开放,增加平均日观赏值,延长寿命。其中山梨酸的保鲜效果优于水杨酸。     

不同浓度多效唑对盆栽东方百合生长的影响

以东方百合星球大战为试验材料,采用50、100、150 mg/L的多效唑溶液土壤浇灌处理方式,探索其对百合生长的影响。结果表明:多效唑可明显降低百合植株的高度,使开花期推迟,茎生根数增加,根长受到抑制;随着多效唑处理浓度的增加,植株底部的落叶数增多,成花株数减少,观赏价值降低。采用50 mg/L多效唑处理,百合矮化效果较理想,观赏性较好。     

History, origin and extent of soil erosion on Easter Island (Rapa Nui)

The isolated Easter Island (Rapa Nui) is an outstanding example of land degradation caused by land use in a sensitive ecosystem. The focus of the investigation was placed on Poike peninsula, the most eastern part of Rapa Nui. While Poike peninsula was once supplied with fertile soils, in large areas desertification takes place today. Detailed analysis of soil profiles allowed the reconstruction of the history and of causes and effects of soil erosion and gullying in the context of land use history and cultural evolution. The results of the stratigraphic analysis prove that from the beginning of human settlement around AD 300/600 until AD 1280 the agriculture on Poike peninsula was characterised by sustainable land use and a traditional type of agro-forestry. Soil erosion was not significant. At around AD 1280 the woodland on Poike, dominated by the endemic palm Jubaea sp., was cleared by slashing and burning. Intensive farming on the upper slopes of the volcanic peninsula resulted in sheet erosion lasting until the 20th century. Settlements and ceremonial places which were built around AD 1300 on downslope areas were buried soon by sediments. Agriculture ceased around AD 1400 on downslope areas as the fertile soils were completely eroded. From AD 1400 until the late 19th century sheet erosion and the accumulation of fine-layered sediments migrated upslope. On average 8.6 Mg of soil per hectare and per year were reworked by erosion (eroded and accumulated within the catchment). Gullying began on Rapa Nui with the sudden increase in the number of sheep during the early 20th century. Gullies are still developing on the island and their ongoing enlargement created extended badlands on Poike which pose a significant problem for ecological and archaeological conservation strategies. Gullying rates exceed 190 Mg ha^{− 1} y^{− 1}.