核桃茎段培养影响因素研究

以晋龙1号核桃的当年生新梢顶芽以下4～5个芽段为试材,通过选择最佳的采样时期,调整外植体灭菌剂浓度与灭菌时间,选择最佳的继代增殖培养基,调节培养室的温度条件与继代间隔时间,以及调整生根培养基的生长素浓度与暗培养时间等综合技术措施,可使外植体的初培成活率提高至60%以上,继代增殖系数提高至3.0以上,生根率达到50%。     

‘薄壳香’核桃组培中的褐化及防止措施研究

 以‘薄壳香’核桃为试验材料, 对其组织培养过程中褐化的发生及防止措施作了探讨。结果证明: 褐化发生程度与培养温度、培养基中激素浓度和无机盐含量、外植体本身的生理状态等因素有关;较高培养温度、培养基中较高浓度无机盐、较高浓度激素及木质化程度高的外植体都会促进褐化的发生;培养基中加入抗氧化剂会抑制褐化的发生。     

美国黑核桃组织培养快繁技术研究

采用组织培养方法对美国黑核桃进行培养。通过试验选择出获得外植体的最佳方法———即获得幼态型外植体是组培的关键。探讨了抑制褐化现象和适宜芽增殖的培养基     

‘绿岭’核桃带芽茎段的组织培养和快速繁殖

以‘绿岭’核桃带芽茎段为试材,采用组织培养方法,研究了植物生长调节剂、珍珠岩对其快速繁殖、瓶内生根及移栽成活的影响,以期构建‘绿岭’核桃初代培养、继代增殖、瓶内生根和移栽驯化的完整体系,建立高效组培快繁体系。结果表明：茎段腋芽生长的最佳培养基为DKW+1.2 mg·L^-1 6-BA+0.012 mg·L^-1 K-IBA,培养30 d后初代苗高为31.48 mm;最佳继代增殖培养基为DKW+0.6 mg·L^-1 6-BA+0.010 mg·L^-1 K-IBA,增殖系数可达5.31;最佳瓶内生根培养基为1/2DKW+15 mg·L^-1 K-IBA,生根率51.85%;炼苗后移栽到培养土、珍珠岩(1∶1)+ABT 500 mg·L^-1混合基质中,成活率达33%以上。     

核桃组织培养技术综述

分别对核桃和山核桃属植物的组织培养中外植体选择与消毒、外植体褐化问题、外植体的主要诱导技术及外植体成苗以后生根技术研究等进行综述,展望其发展前景。     

南板蓝根离体快繁中的褐变控制

从取材方式、灭菌前预处理、培养基添加抗褐变剂3方面研究降低南板蓝根芽体褐变的方法。结果表明:掰芽取材和及时流水冲洗处理对减轻南板蓝根芽体褐变有显著的效果;培养基中添加0.5%活性炭吸附剂对减轻褐变有一定作用,添加抗氧化剂柠檬酸300～500 mg/L浓度对褐变的抑制效果不明显。掰取芽体后立即流水冲洗2 h,培养基中添加0.5%活性炭,能有效减轻芽褐变和利于快速增殖。     

蓝莓茎段离体快繁研究

以大兴安岭地区野生蓝莓苗木为试材,取当年生幼嫩茎段为外植体,探索建立蓝莓组培苗的快繁体系。结果表明:外植体消毒处理组合为75%乙醇处理10~15s,0.1%升汞处理10min。培养基为WPM培养基,愈伤组织诱导及不定芽增殖时期应用的激素组合ZT 2.0mg/L+NAA 0.2mg/L。利用IBA蘸根法诱导不定根,激素浓度为200μg/mL,芽诱导率超过80%,生根率超过70%。     

抑制核桃组培中的褐化现象初探

以薄皮核桃茎尖为试材，对其分化生长过程中的褐化现象进行研究。经多次试验初步表明，为抑制褐化及保证茎尖正常分化生长，先将茎尖接种于1／2MS 2g活性碳的培养基中，置于5℃冰箱中黑暗培养7天后取出，再转接于DKW 6—BAl.0mg／L IAA0．01mg／L 5ml20％硫代硫酸钠的培养基中，置于25℃室内光照环境下培养，每隔15～20天转换1次培养基，能有效地抑制褐化，确保核桃茎尖在整个培养过程中正常分化生长。     

影响蝴蝶兰组培苗生产中褐变的因素及其调控

蝴蝶兰是兰科植物中栽培广泛、应用普及最多的种类之一,由于花形奇特,花色丰富,深受人们喜爱,有较高的观赏价值和经济价值,市场需求量大。目前蝴蝶兰的种苗生产多采用组织培养来进行,但是组培过程中褐变现象的发生,严重阻碍了蝴蝶兰种苗的规模化生产。本文对导致蝴蝶兰组培苗褐变的影响因素及其调控作了有益的探索,希望对蝴蝶兰的种苗生产能有所帮助。     

Factors affecting the shoot multiplication of Persian walnut (Juglans regia L.)

A number of experiments were conducted to identify suitable procedure for in vitro shoot multiplication of Persian walnut (Juglans regia L.). Three different nutrient media (DKW, MS and WPM) and three different gelling agents (Phytagel, Difco Bacto agar and a mixture of Phytagel and Difco Bacto agar) were studied in the first experiment. Driver and Kuniyuki walnut (DKW) medium solidified with 2.2 g l⁻¹ Phytagel was found optimum. Performance of explants was better on DKW medium than on MS and WPM. The DKW and MS media were not significantly different from each other, but both of them were significantly better than WPM, which was a very poor medium for this species. Phytagel alone was significantly better than Difco Bacto agar or Phytagel combined with Difco Bacto agar. In another experiment different concentrations of BA were studied. Medium containing 1.0 mg l⁻¹ BA and 0.01 mg l⁻¹ IBA was the best, although medium containing 0.6 and 0.8 mg l⁻¹ BA were also successful, and utilisation of 0.4 mg l⁻¹ BA and 0.01 mg l⁻¹ IBA was optimum for shoot elongation. Application of different kinds of auxins (IAA, IBA and NAA at 0.01 or 0.1 mg l⁻¹) with 1.0 mg l⁻¹ BA were also studied. Media containing IBA were significantly better than media containing IAA for shoot fresh weight, but neither of them was significantly different from media containing NAA. Application of 0.01 mg l⁻¹ or 0.1 mg l⁻¹ auxin, with 1.0 mg l⁻¹ BA, was not significantly different for shoot multiplication of Persian walnut. The morphology of shoots on media containing 0.01 mg l⁻¹ IBA was the best.     

影响大白菜游离小孢子培养因素的研究

采用游离小孢子培养方法,研究了花期、活性炭和取蕾时间对大白菜小孢子出胚率的影响。结果表明:科萌78盛花期取蕾培养的出胚率为每蕾79.5个胚,是初花期的3.0倍、末花期的6.3倍;科萌45盛花期取蕾培养出胚率为2.8个胚,而初花期和末花期的出胚率都为0。在NLN-13培养基中添加活性炭(800 mg/L)后,金夏55出胚率提高了71.5%,科萌45的出胚率由0增加为3.2个;新三包头下午取蕾的出胚率是上午的2.0倍,科萌45上午取蕾出胚率为0,下午出胚率为4.1个。     

影响早熟油桃茎尖培养增殖效率的因素

以早熟油桃华光、曙光为试材,研究了外源植物生长调节剂种类及浓度组合、培养基种类、暗培养时间等因素对茎尖培养增殖效率和试管苗生根的影响。结果表明:不同浓度的TDZ和KT对华光、曙光油桃增殖效应不同,在G培养基中加入TDZ2.0mg/L和KT1.5mg/L处理效果最好。1/2MS培养基中附加IBA有利于华光、曙光汕桃的生根;华光油桃生根不必经过暗培养;曙光经过6d或9d暗培养能大大提高生根率和有效根数量。     

Factors affecting shoot development in apically dominant Acer cultivars in vitro.

Summary

Axillary shoot cultures of both Acer saccharinum L. ‘Pyramidale’ and A. platanoides L. ‘Crimson King’ displayed strong apical dominance and prolific basal callus in vitro, which was not conducive to rapid multiplication and rooting. Basal callus was reduced in ‘Pyramidale’ by replacing 6-benzylaminopurine (BAP-5μM) with zeatin (5μM), but this also reduced axillary shoot growth. The addition of 2,3,5-triiodobenzoic acid (1-20 μM) altered callus development and promoted a concentration-dependent increase in axillary shoot growth. Supplementing medium with thidiazuron (0.005 and 0.05 μM) in addition to BAP (1 μM) enhanced shoot growth, especially with nodal shoot sections, and increased subsequent rooting. Although thidiazuron also increased basal callus, this correlated with better shoot growth in ‘Crimson King’. Selection of apical buds from ‘Crimsom King’ stockplants was essential for the establishment of sustainable cultures; axillary bud-derived expiants quickly died. Once shoots of ‘Pyramidale’ and ‘Crimson King’ had elongated, they could be readily rooted in vitro, and plantlets were successfully weaned under high humidity ‘dry fog’.     

葡萄大棚内温床催根营养钵扦插育苗技术

3月初在塑料大棚内利用电热温床对用ABT6号生根粉处理过的葡萄插条进行催根处理，生根后移至大棚内的营养钵中，保持适宜的温湿度，精细管理，4月下旬开始炼苗，5月份即可露地定植，实现当年扦插当年定植建园。     

Factors affecting the quality and in vitro germination capacity of strawberry pollen

Summary

Poor pollen quality and germination capacity curtails early yield in strawberry. The aim of this study was to establish a reliable method for in vitro assessment of strawberry pollen germination ability and to investigate further the effects of photoperiod and gibberellin on pollen germination and quality. In the first part of the study, pollen from seven strawberry cultivars (Chandler, Selva, Tudla, Camarosa, Eris, Pajaro and Irvine) was collected and its germination capacity and incidence of deformed pollen grains assessed in vitro using the hanging-drop technique. Highest germination rates, in ‘Selva’, were observed in a nutrient medium of 10% sucrose. Addition of calcium nitrate to the medium decreased the germination percentages of all cultivars. There was no significant difference, on average, between the germination rate at 20° and 25°C. Genetic factors affected the incidence of deformed pollen grains significantly, with ‘Pajaro’ showing the highest percentage (76%). In the second part, groups of young strawberry plants, cultivar Seascape, grown either under natural early spring conditions or under long-day or short-day conditions were sprayed once with GA₃ at 0, 50, or 200 mg l^–1. Pollen germination and deformation and stamen length were assessed three months later. In plants of the first group, GA₃ at 50 mg l^–1 increased pollen germination and decreased the incidence of deformed pollen grains, while GA₃ at 200 mg l^–1 decreased pollen germination without affecting the formation of deformed pollen grains. Plants of the second group showed a higher rate of pollen germination under long than under short days. GA₃ at 200 mg l^–1 decreased pollen germination under either short- or long-day conditions compared with the controls but doubled the percentage of deformed pollen only under short days. Stamens in control plants grew four times as long under long- than short-day conditions. GA₃ did not affect stamen length under long days but significantly enhanced their growth under short days.     

丽格海棠离体培养植株再生影响因素的研究

以丽格海棠叶片、叶柄和花茎为试材进行培养.研究了不同浓度的NAA和6-BA对叶片不定芽的诱导作用,同时研究了不同类型的外植体,叶片的不同部位对不定芽的诱导影响,结果表明:MS 6-BA1.5mg/L NAA0.2-0.5 mg/L有利于不定芽的诱导.叶片再生不定芽的能力最强,而叶片中以叶中和叶侧的再生效果最好.1/2Ms NAA1.0 mg/L有利于不定根的诱导.     

Factors affecting intraspecific variation in home range size of a large African herbivore

Factors affecting intraspecific variation in home range size have rarely been examined using modern statistical and remote sensing methods. This is especially true for animals in seasonal savanna environments in Africa, despite this biome??s importance for both conservation and development goals. We studied the impacts of spatial and temporal variability in environmental conditions, along with individual and social factors, on home range sizes in African buffalo (Syncerus caffer) in northeastern Namibia. Our data set spans 4?years, is derived from 32 satellite tracking collars, and contains over 35,000 GPS locations. We used the local convex hull method to estimate home range size from 31 buffalo captured at 6 sites. We used a variety of remotely sensed data to characterize potential anthropogenic and natural boundaries, as well as seasonal and temporal heterogeneity in environmental conditions. Using an information-theoretic, mixed effects approach, our analyses showed that home ranges varied over two orders of magnitude and are among the largest recorded for this species. Variables relating to vegetation and habitat boundaries were more important than abiotic environmental conditions and individual or social factors in explaining variation in home range size. The relative contributions of environmental, individual, social, and linear boundary variables to intraspecific home range size have rarely been examined and prior to this had not been assessed for any species in seasonal savannas of Africa. Understanding the factors that condition space-use patterns of wildlife in this area will lead to better-informed conservation and sustainable development decisions.     

影响枸杞浓酒中类胡萝卜素保存率因素的研究

抗氧化剂和紫外光是影响枸杞浓酒中类胡萝卜素保存率的主要因素,均质次数、时间、温度、酸度等,对类胡萝卜素保存率无显著影响。     

Factors affecting the persistence of traditional agricultural landscapes in Slovakia during the collectivization of agriculture

Collectivization of agriculture (1950s–1970s) was one of the most important periods in landscape development in Slovakia. Traditionally managed agricultural landscapes, that covered more than half of the Slovak territory, were transformed into large-scale fields and only fragments of traditional agricultural landscapes survived. We mapped the remaining traditional agricultural landscapes using aerial photos and historical maps. We then statistically analyzed the various geographical factors and their influence on the transformation process of traditional and collectivized fields, i.e., slope steepness, soil fertility, distance from settlements and isolation from regional capital cities. The comparison was performed using classification tree analysis. We constructed a set of decision rules that explain why fields were managed traditionally or collectivized. Our findings show that traditional agricultural fields were more likely to persist on steep terrain, less fertile soils, and on locations that were closer to the settlements, but more isolated from the regional capital cities. Steepness played the most important role: small-scale fields located on steep areas were not accessible to heavy machinery and therefore, frequently survived the collectivization. We show that the selected geographical factors are good explanatory variables for the collectivization of arable fields and orchards. For vineyards and grasslands, however, the explanatory power of the selected geographical factors is lower, and we suspect that other factors, not depicted in the analysis play an important role.