Long term t in vitro storage of lily: effects of temperature and concentration of nutrients and sucrose

Methods for long-term preservation of lily germplasm were examined. t In vitro regenerated bulblets of 10 lily (t Lilium L.) genotypes (Asiatic hybrids, Oriental hybrids, t L. longiflorum and t L. henryi) were stored for 28 months at -2 °C and 25 °C on four different media: 1/4 or full strength Murashige and Skoog nutrients with 9% (w/v) or 6% sucrose. Sprout growth, bulb growth, and viability were determined. The combination of 1/4 strength MS nutrients and 9% sucrose gave the highest reduction in sprout and bulb growth, the highest viability and the highest percentage of regrowth after 28 months of storage. At 25 °C, all lily genotypes survived 28 months of storage under these conditions. At -2 °C, Asiatic and Oriental hybrids survived 28 months of storage, whereas genotypes of t L. longiflorum and t L. henryi survived 6 months of storage, but died during prolonged storage. This revised version was published online in June 2006 with corrections to the Cover Date.     

The role of sexual and vegetative reproduction in the population maintenance of a monocarpic perennial herb,Cardiocrinum cordatum var. glehnii

Because monocarpic perennial plants have only one reproductive opportunity in their entire life, they need to ensure offspring production. Some plants reproduce both sexually and vegetatively, and vegetative reproduction could possibly compensate for seed production. Therefore, the role and significance of these reproductive modes is likely to differ between monocarps and polycarps, which can reproduce many times. Cardiocrinum cordatum var. glehnii is a monocarpic perennial that reproduces both sexually and vegetatively (bulblet formation). Here, we investigated the characteristics and contribution to population maintenance of sexual and vegetative reproduction to reveal the significance of these two reproductive modes in this species. First, we found that bulblet formation occurred in plants after the three‐leaved rosette stage. Second, resource allocation experiments revealed that although resources were mainly invested in fruit maturation after the flowering season, resource allocation was switched from sexual reproduction to vegetative reproduction if seed production was insufficient. Third, the outcrossing rate in this species varied greatly according to the environment surrounding the population. However, reproductive assurance by selfing kept seed production stable even if flowers did not receive sufficient pollen for full seed set via outcross pollination, and moreover, there was no intensive inbreeding depression. Finally, genotypic identification of ramets suggested that daughter ramets derived from vegetative reproduction received the space that the mother flowering ramet had occupied until the previous year.     

水杨酸对两个品种百合鳞茎膨大的作用及其与内源激素含量的关系

百合品种‘精粹’的鳞茎周径和鲜重随着叶面喷施水杨酸（SA）的浓度的增加而增加;品种‘普瑞头’鳞茎周径和鲜重也随着叶面喷施SA的浓度的变化而变化,其中以0．5mmol·L^-1SA的效应最明显。叶面喷施SA的百合鳞茎中ABA和GA3含量下降,IAA和ZR含量上升,鳞茎中（IAA＋GA3）／ABA、IAA／GA3比值均比未喷施SA的高,而IAA／ZR、GA3／ZR比值则比未喷施SA的低。显示鳞茎膨大与内源激素的含量相关。     

东方百合鳞片繁殖小鳞茎发生的形态学观察

采用解剖学方法研究东方百合鳞片扦插繁殖中小鳞茎的组织发生过程。结果表明:小鳞茎的形态发生起源于鳞片近轴面基部的几层薄壁细胞,细胞脱分化后形成分生组织,再经过器官发生途径形成小鳞茎,属于外起源。小鳞茎发生过程可分为未分化期、启动期、生长锥形成期、小鳞片原基和根原基形成期、小鳞茎形成期。     

Regeneration of bulblets from twin scales ofCrinum macowanii in vitro

Tissue culture techniques were applied to study the regeneration and growth of bulblets from bulb scale segments ofCrinum macowanii Bak. (bush- or march lily)in vitro. Shoots were induced on twin scales taken from the basal plate region of flowering-size bulbs on Murashige and Skoog (MS)-medium containing 0–20 mg l^–1 NAA and BA and a modified MS medium (MMS medium) containing 1.25 mg l^–1 ancymidol (A-Rest^TM), 0.1 mg l^–1 NAA and 0.1 mg l^–1 kinetin (ANK). Large bulblets could only be initiated on the latter. Subsequently the bulblets of 5 mm or more in diameter were trimmed and split in half, and secondary plantlets were regenerated on MMS-medium containing ANK or MS-medium without any growth regulators which in turn grew into bulblets suitable for splitting within 12–16 weeks. A total of 700–1000 bulblets could be obtained from each initial bulb within 12 months. Anatomical studies showed that the shoots were initiated from the epidermis and hypodermis on the abaxial surface of the meristematic tissue of the basal plate of the bulb scale. This technique is useful for the multiplication and preservation of a genotype, since plantlets regenerated in this manner should be genetically uniform.     

火百合花器的鳞茎诱导和增殖培养研究

采用4.5 ～6.5cm长、花苞青色未开放的火百合花蕾作材料,切取其子房、花柱、花丝为外植体进行鳞茎诱导,结果表明:花丝的鳞茎诱导率最高,其次是花柱,子房的诱导率最低。以子房和花柱为外植体诱导出的鳞茎个体大小不一(1～7mm) ,以花丝为外植体诱导出的鳞茎则普遍偏小,但较整齐一致(3～4mm) ;小鳞茎诱导的最佳6-BA浓度是1.0mg/L。研究了基本培养基、6-BA浓度、NAA浓度对小鳞茎增殖的效应及不同蔗糖浓度对小鳞茎增重的影响,结果表明:小鳞茎增殖的最佳培养基是:MS+6-BA2.0 mg/L+NAA0.2 mg/L,4 %蔗糖对鳞茎增重效果最好。     

<Emphasis Type="Italic">In vitro</Emphasis> regeneration and bulblet growth from lily bulbscale explants as affected by retardants,sucrose and irradiance

Bulbscales of oriental lily hybrid Star Gazer were used as the explants. Bulblets were formed on the basal portion of the excised bulbscales on MS medium supplemented with growth retardants, different sucrose concentrations and exposed to continuous light or dark. ^{Alar, Cycocel} and Paclobutrazol in concentration 1 mg dm⁻³ produced higher number of bulblets as compared to the control. The number of bulblets, however, decreased with the increase in concentration of the growth retardants. The number of bulblets was higher at 90 than at 60 g dm⁻³ sucrose and when the bulbscales were exposed to continuous light than to darkness. The growth retardants, higher sucrose concentration and continuous dark stimulated fresh mass of bulblets. The number of bulblets having roots and leaves decreased in medium with Alar, Cycocel and Paclobutrazol as compared to the control. A few bulblets produced roots and leaves in medium with 90 g dm⁻³ sucrose and none of the regenerated bulblets produced leaves under continuous dark.     

新疆野生种与栽培种郁金香的杂交种子无菌萌发和鳞茎形成

新疆野生种与栽培种郁金香的杂交F1种子于4℃低温下培养36-67d后萌发,随后于15℃下培养3-5个月形成鳞茎。‘小黑人’×柔毛郁金香、‘小黑人’×天山郁金香和‘小黑人’×伊犁郁金香F1种子的萌发率差异显著,分别为60．37％-63．89％、80．28％-81．25％和3．75％-4．45％。‘小黑人’×柔毛郁金香和‘小黑人’×天山郁金香F1的鳞茎分别在添加6-BA2．0mg·L^-1（单位下同）＋KT1．0＋TDZ0．1和6-BA5．0＋KT0．4的1／2MS培养基中增殖。‘小黑人’×天山郁金香F1种子萌发后有41．67％呈畸形,畸形的萌芽在添加6-BA2．0＋KT0．4的1／2MS培养基中可诱导出鳞茎并增殖。     

Effects of storage temperature and sucrose on bulblet growth, starch and protein contents in in vitro cultures of Hyacinthus orientalis

The scale segments of the bulblets of Hyacinthus orientalis L. cv. Anna Marie were examined to improve their growth and development with cold-pretreatment and sucrose. The cold-pretreated (4 °C for 4 months) segments showed higher growth and better development of the bulblets on medium without sucrose than ones stored at 20 °C. A rapid decrease in starch content of bulb pieces was found during the first 2 weeks in all cultures and thereafter the content decreased gradually. A scanning electron microscopic observation during the bulblet growth and development showed a gradual decreasing trend of the starch granules from 2 to 16 weeks of the cultures. SDS-PAGE electrophoresis revealed the presence of a characteristic polypeptide of approximately 45 kD, which is assumed to be a major storage protein in the bulblets.