Growth and development of Lilium longiflorum ‘Nellie White’ during bulb production under controlled environments : II. Effects of shifting day/night temperature regimes on scale bulblets

One-year old scale bulblets of Lilium longiflorum Thunb. ‘Nellie White’ (Easter lily) were grown for 107 days during growth period 1 (GP-1) in six growth chambers under constant day/night temperature regimes of 30/26, 26/22, 22/18, 18/14, 14/10 and 10/6 °C. Subsequently, half of the plants in each temperature regime were transferred to 18/14 °C and the other half continued at the six constant temperature regimes. Both groups of plants were grown for an additional 89 days in growth period 2 (GP-2). Continuous temperatures of 26/22, 26/22–22/18 and 26/22–18/14 °C produced the greatest increase in basal bulb fresh weight (the main planted bulb), basal bulb circumference and stem bulb fresh weight, respectively. However, shifting these optimal temperatures to 18/14 °C during GP-2 resulted in a lower increase in basal bulb fresh weight and circumference. The optimum range for stem bulb production was expanded to 30/26–14/10 °C by shifting to 18/14 °C. The greatest increase for basal root growth occurred at 14/10–10/6 °C and for stem root growth at 14/10 °C. The temperature shift did not affect either root type. Maximum increase for stem length was at 26/22 and 22/18 °C and for stem plus leaf weight at 14/10 °C under constant temperature regimes. Transferring the plants from 10/6 to 18/14 °C resulted in the greatest increase in stem length and from 10/6 and 14/10 to 18/14 °C in the greatest increase in stem plus leaf weight. The greatest increase in the number of leaves occurred at 26/22 and 10/6 °C, but this growth parameter was unaffected by shifting to 18/14 °C, indicating that leaf number was determined in GP-1. Bulbils developed only when bulbs at high GP-1 temperature regimes (30/26 and 26/22 °C) were transferred to 18/14 °C during GP-2. Lower temperatures tended to favor an increase in flower bud production under continuous temperature regimes, while shifting to 18/14 °C increased flower bud production after initially high and low temperatures. Meristem abortion was greatest at 30/26 °C followed by 26/22 °C, but was not affected by temperature shifts in GP- 2. Thus, it is concluded that the abortion was induced or initiated during GP-1.     

Long-Term Follow-up of Superficial Digital Flexor Tendonitis Treated by a Single Intralesional Injection of a ReGeneraTing Agent in 51 Horses

ReGeneraTing Agents (RGTA) are nanopolysaccharides engineered to mimic heparan sulfates and have been shown to stimulate tissue repair and healing (skin, cornea, gingival, and muscle) in several animal models of injury and in human medicine. A preliminary study, monocentric and uncontrolled, was conducted to evaluate the efficacy of a dedicated RGTA (named Equitend) in improving the healing quality of the injured tendon after a single and ultrasound-guided intralesional injection. Improvement of ultrasonographic appearance of tendinous or ligamentous lesion was documented at least over 4 months in Equitend-treated horses and was further supported by another study on superficial digital flexor tendonitis, in 51 horses (16 French Standardbred trotters (ST), 13 Thoroughbreds (TB), and 22 eventers). Long-term follow-up of these horses showed high rates of return to racing, with 95% of eventers, 87.5% of French ST, and 77% of TB. The mean duration before the first race or competition was 6.6 and 7.4 months for ST and eventers, respectively. The group of 16 treated ST was then compared with a matched control group, showing that the Equitend-treated group was able to return to a higher level of earning after lesion (74% vs. 15% in the control group). Furthermore, the Equitend-treated group was back in racing 2.4 months earlier than the control group.     

兰州百合鳞茎再生繁殖体系的建立

[目的]建立兰州百合鳞茎快繁体系,并测定丛芽与鳞茎的淀粉含量,为系统研究兰州百合鳞茎离体再生过程中淀粉的代谢奠定基础.[方法]以兰州百合鳞片为外植体,探讨不同消毒剂组合、激素与蔗糖用量对鳞茎诱导培养过程的影响.[结果]随着75％乙醇（10～30 s）与0.1％升汞消毒时间（7～10min）的延长,外植体鳞片污染数不断下降,但诱导芽数表现为先上升后下降的趋势,以75％乙醇消毒30 s＋0.1％升汞消毒10 min组合的消毒效果最好,外植体污染率和芽诱导率分别为12.33％和91.00％.使用1000倍多菌灵处理10 min后,再使用75％乙醇30 s ＋0.1％升汞7～13 min组合进行消毒,可明显降低鳞片污染率3.00％～5.00％（绝对值）.在MS＋0.03 mg/L NAA＋30.0 g/L蔗糖＋5.0 g/L琼脂培养基中添加6-BA 0.5～1.0 mg/L,可显著提高平均芽诱导数;在MS＋5.0 g/L琼脂培养基中添加30.0～60.0 g/L蔗糖,对外植体芽诱导无明显影响;培养基MS＋1.0 mg/L 6-BA＋0.03 mg/L NAA＋30.0 g/L蔗糖＋5.0 g/L琼脂是外植体芽诱导的最适培养基.MS＋0.50 mg/L 6-BA＋0.03 mg/L NAA＋30.0 g/L蔗糖＋5.0 g/L琼脂为适宜增殖培养基,芽增殖系数达最高,为3.67.在MS培养基中添加60.0～90.0 g/L蔗糖可明显促进鳞茎的形成,以添加90.0 g/L蔗糖处理的鳞茎重量最高（99.30mg）.小鳞茎的淀粉质量分数比丛芽增加62.34％.[结论]以鳞片为外植体建立的兰州百合鳞茎再生繁殖体系具有可行性;在丛芽至小鳞茎形成阶段淀粉含量明显升高,小鳞茎的形成与淀粉含量升高密切相关.     

Breeding and post-breeding responses of woodland birds to modification of habitat structure by deer

Birds in woodland can be affected by increasing deer populations through changes to vegetation structure and potential impacts on foraging resources; these effects need to be better understood. Effects of deer browsing are reported from a replicated split-plot exclusion experiment in English coppiced woodland. All stages of growth were examined up to eight years after felling. We used standardised mist-netting (totaling 1920 h) to sample birds in breeding and post-breeding periods. Deer browsing strongly altered vegetation structure by reducing canopy cover and shrub layer foliage density. However deer did not affect invertebrate density per unit of foliage, providing no evidence of an ungulate-mediated plant chemical response affecting forage quality for invertebrate herbivores. At avian guild level, significantly more ground and understorey foraging birds were captured where deer were excluded, and negative responses to browsing were more marked for pooled migrants than pooled residents. At the species level, especially pronounced negative effects were evident for dunnock (Prunella modularis) and garden warbler (Sylvia borin); approximately five times more dunnocks were captured in deer exclosures than in browsed vegetation. We also detected negative responses to browsing by nightingale (Luscinia megarhynchos) and long-tailed tit (Aegithalos caudatus). No significant positive responses to browsing were detected. For some species the use of young re-growth increased post breeding relative to the breeding period, including a marked shift by pooled residents that involved a disproportionate number of juveniles. Previous studies in North America have shown that, through vegetation modification, ungulate activity can alter woodland bird assemblages; as far as we are aware this is the first experimental demonstration of effects in Europe, and at low to moderate browsing intensity typical of the wider landscape scale.     

兰州百合子球高效培育与基质选择研究

为缩短兰州百合培育周期,研究了兰州百合子球培育与基质筛选。以鳞片扦插60 d的兰州百合子球小苗为材料,通过连续两个生长季的栽培,研究了基质配比、栽培深度、栽培密度等因素对子球膨大的影响。结果表明,在草炭︰细砂=3︰1的基质中,采用栽培深度为子球高度1倍、栽培密度为12 cm×12 cm时,子球直径能够达到1.7 cm以上,可获得较好的子球膨大效率,缩短子球培育时间。     

东方百合试管鳞茎培育方式的比较

为促进试管鳞茎抽薹,缩短其形成商品球的时间,以东方百合试管鳞茎为材料,采用不同的培育方式,研究其品质与抽薹率的影响。对东方百合试管鳞茎不同培育方式的比较研究,结果表明：瓶苗冷藏或用基质冷藏,冷藏后的试管鳞茎生理变化规律相同,即淀粉含量、蛋白质含量均降低,可溶性糖含量和还原糖含量均升高;而用基质冷藏或用瓶苗冷藏,暗培养的试管鳞茎抽薹率都高于光照培养;采用暗培养或光照培养,基质冷藏的抽薹率都高于用瓶苗冷藏。工厂化生产百合种苗时宜采用暗培养试管鳞茎结合种前用基质冷藏的培育方式。     

低温层积对百合试管小鳞茎活力的影响

为提高百合试管小鳞茎的适用性,以自繁的百合试管小鳞茎‘Siberia’为材料,研究低温层积对小鳞茎活力表达的影响。结果表明,-2℃、2℃低温处理可有效改善试管小鳞茎发芽率、活力指数、破土能力、抽薹速度等活力指标。研究认为低温层积处理在135~165 天为最佳活力表达期,并因此通过促进抽薹进而高度相关地（相关系数为1.00**）提高了百合籽球（围径6~9 cm）收获率。低温层积是百合试管小鳞茎活力实现田间栽培不可或缺的措施。     

寒地百合小鳞茎膨大发育与生物量动态变化

研究了百合小鳞茎在哈尔滨地区膨大发育过程中生物量累积与分配动态变化规律。结果表明,百合小鳞茎在哈尔滨地区的膨大发育过程可划分为5个阶段,即鳞茎失重消耗期、补偿期、充实膨大增重期Ⅰ、生长受抑期和充实膨大增重期Ⅱ。生物量分配规律:苗期至现蕾期以茎叶部分为主,现蕾后生物量主要分配于地下小鳞茎,分配于新鳞茎和根中的生物量始终很低。     

百合试管鳞茎诱导及膨大技术的研究

以东方百合"Sorbonne"试管苗为材料,研究了蔗糖浓度、大量元素、培养基状态、多效唑和水杨酸浓度对百合试管鳞茎诱导及膨大的影响。结果表明,蔗糖浓度为60 g.L-1时新增鳞茎数最多,鳞茎形成率达75%,蔗糖浓度120g.L-1处理最有利于鳞茎膨大;高浓度的大量元素有利于鳞茎的膨大,而不利于鳞茎的诱导,3MS时形成的鳞茎最大,但鳞茎形成率则下降到14.6%;液体培养基对鳞茎鲜重影响显著;多效唑浓度10mg.L-1处理能促进鳞茎的诱导和膨大;水杨酸处理则能显著提高试管鳞茎的数量。     

甜菜原生质体培养再生植株的研究

以栽培甜菜的未授精胚珠或胚为外植体，在ＭＳ附加ＮＡＡ和ＢＡ的培养基上诱导愈伤组织，选择胚性愈伤组织进行继代培养，从该愈伤组织分离原生质体并以液体浅层法或半固体琼脂糖法培养在一系列培养基上，植板率为０．０１％～１．２％．再生愈伤组织形成后，转入固体培养基（ＭＳＢ）上培养，再转入分化培养基上分化出苗，分化率可达２．５％，由愈伤组织上切下分化苗在生根培养基上很容易诱导生根。