Provenance Variation in Seed Morphometric Traits, Germination, and Seedling Growth of Cordia africana Lam

Patterns of genetic variation in Cordia africana, a tropical timber species, were evaluated at the population level. Bulk seed samples were collected from six natural populations in Ethiopia and examined for variations in seed morphometric traits, seed germination, and seedling growth at nursery stage. Analysis of variance revealed significant differences among provenances in all studied attributes except root collar diameter after 4 months of growth. The provenance effect, as determined by broad sense heritability, was 71–98% for seed morphometric traits, 80% for germination capacity, 42% for germination energy, 57–58% for seedling height and 3–13% for root collar diameter. Seed weight showed a significant positive correlation with altitude and negative correlation with mean annual temperature of seed origin. Germination energy was significantly correlated with longitude and mean annual rainfall. Seedling parameters and geo-climatic variables of seed origin were fairly correlated. A significant intercharacter correlation was found between seed length and seed weight, between root collar diameter at the age of 4 months and seed length and weight, as well as between seedling height after 4 and 8 months of growth. It can be concluded that the observed patterns of variation will have implications for genetic resources conservation and tree improvement.     

Germination of <Emphasis Type="Italic">Juniperus procera</Emphasis> seeds in response to stratification and smoke treatments,and detection of insect-damaged seeds with VIS + NIR spectroscopy

Seeds of Juniperus procera collected from five provenances across its geographic range in Ethiopia were subjected to cold-moist stratification at 5°C or 10°C for 6–12 weeks. The effect of aqueous smoke solution in overcoming the light requirement for germination, and the potential of visible (VIS) and near infrared reflectance (NIR) spectroscopy for sorting sound and insect-damaged seeds were also investigated. Highly significant differences in germination were detected among provenances (P < 0.0001) and stratification periods (P < 0.0001), but not between temperature regimes (P=0.111). Seeds from the south and southeast distribution ranges had higher percentage germination after 6 weeks of stratification than seeds collected from north, northwest and central ranges of distribution. The smoke treatment did not affect germination regardless of whether the seeds were exposed to light. Exposure to light increased germination capacity three fold. Sound and damaged seeds were distinguished with 90% accuracy using VIS + NIR spectroscopy. It can be concluded that dormancy in juniper seeds varies with provenances, and cold stratification for 6 weeks alleviates dormancy in some seed lots. Tentatively, smoke treatment seems ineffective in overcoming photo-dormancy in juniper seeds. VIS + NIR spectroscopy has demonstrated a great potential for sorting damaged seeds, thereby upgrading seed lot purity.     

不同药剂浸泡处理对山桃稠李种子发芽的影响

为了促进山桃稠李种子萌发,提高山桃稠李种子繁殖的发芽率,以清水作为对照,采用不同浓度的高锰酸钾、过氧化氢、赤霉素对山桃稠李种子进行处理,比较不同药剂、不同浓度及不同处理时间对山桃稠李种子发芽的影响。结果表明:不同药剂处理的种子发芽率有显著差异,不同处理时间之间没有显著差异,各药剂处理按照发芽率由高到低的顺序排列依次为高锰酸钾、赤霉素、过氧化氢、水处理。对发芽促进效果最佳的组合是0.7%的高锰酸钾浸泡处理48h,发芽率可达88%。     

Germination pretreatment and storage behavior of Terminalia laxiflora seed

Terminalia laxiflora Engl.&Diels.is an important indigenous and multi-purpose species in Ethiopia.However threatened due to low germination and its storage behavior is unknown.In this study,we aimed to(1)test pretreatments for breaking the dormancy of T.laxiflora seed and(2)determine its storage behavior.Seeds were subjected to four pretreatments such as soaking,scarification,high-temperature,and control.Experiments were done before storage and after 2 years of dry storage at cold temperature(-10℃)based on randomized design with four replicates.The first round of experimental results showed that T.laxiflora seeds with high temperature treatments at 78℃for 10 min showed significantly higher germination percentage(80%).In the second round experiment,high-temperature treatment at 78℃for15 min,cold water soaking,high-temperature treatment at78℃for 10 min,hot water soaking,and high-temperature treatment at 78℃for 5 min showed significantly higher germination percentage from the remaining treatments(75,64,58,56,and 53%,respectively).To break the dormancy of T.laxiflora seed and attain good germination result,seeds should be pretreated with high-temperature at 78℃for 10 min to test the initial germination before storage and should be pretreated with high-temperature(at 78℃for15,10,or 5 min),soaked in cold,or hot water for 24 h to monitor the germination after storage.The two experiments show that T.laxiflora produces orthodox seed.     

Vegetative propagation of Prunus africana: effects of rooting medium, auxin concentrations and leaf area

The region of West and Central Africa is endowed with high-value fruit trees and medicinal plants, which are currently traded locally as well as on regional and international markets. Unfortunately, they are all exploited from the wild and there has been little or no focussed effort to domesticate and cultivate them. Prunus africana is one of these important medicinal plant under domestication. A series of nursery experiments were conducted to assess the effects of rooting medium (sawdust, sand and a 50:50 mixture of sand and sawdust), auxin concentration (0, 50, 100, 150, and 200 μg IBA), and leaf area (0, 5, 10, 20, and 25 cm²) on rooting success of juvenile cuttings of P. africana. The percentage of cuttings rooted was significantly greater (P < 0.05) in sawdust (80%), than in sand alone (72%) or in mixture with sawdust (71%). Leaf area also significantly affected the percentage of rooting. Leafless cuttings did not root and were all dead by week 6, but in leafy cuttings rooting ability increased proportionally with leaf area up to 20 cm² (79%). Larger leaf cuttings (25 cm²) rooted at the same level as those of 20 cm². The cuttings with the largest leaves also had the greatest mean number of roots per cutting (14 roots cutting⁻¹), while those with the smallest (5 cm²) leaf area produced the fewest roots (5 roots cutting⁻¹). The application of auxin (IBA) promoted rooting (P < 0.05) up to an optimum application of 100–200 μg IBA per cutting, but 300 μg was supraoptimal. It can be concluded that P. africana is amenable to vegetative propagation. This revised version was published online in June 2006 with corrections to the Cover Date.     

杨树人工种子发芽条件研究初报

为了研究人工种子发芽所必需的营养成份,以辽河杨的腋芽为材料,用4％藻朊酸钠和1.4％Ca溶液等物质做成人工种子后,置于5种处理培养基中进行培养。杨树人工种子置于培养基5 d后,A、B、E处理区尚无变化。C、D处理区开始发芽。20 d后,C处理区发芽率为100％、生根率60％。在D处理区中发芽率达70％,但未能生根。在A、B、E处理区中杨树人工种子既不能发芽也不能生根。根据实验结果推测:人工种子发芽所必需的营养成分可能包括培养基和蔗糖。     

麻栎种子灭虫、贮藏处理方法效果初探

为了提高麻栎人工更新的质量和效果，对麻栎种子采收后，进行了不同方法的处理和贮藏试验，结果表明，麻栎种子采用水浸灭虫法效果最佳，种子发芽率达到84％，生活力提高34．5％；采用室内混沙贮藏法效果最优，种子发芽率提高15％-25％，含水率提高2％-8％。     

紫薇花粉贮藏及花粉活力的分析

分析了3个紫薇品种花粉活力及不同贮藏温度对花粉活力的影响,结果表明:3个紫薇品种鲜花粉活力存在极显著差别.低温有效地延长了花粉活力的保持时间,在4℃条件下,花粉活力保持164.278 h;在-20℃条件下,花粉活力保持141.278 h;在室温条件下,紫薇花粉活力仅保持18.444 h.     

山茶花粉生活力及贮藏条件初探

以山茶两种开放程度花朵（初开和盛开）的花粉为试材,采用无机酸法和联苯胺染色法研究了花朵开放程度和贮藏条件对花粉生活力的影响.结果表明：无机酸法不适于山茶花粉生活力的测定,联苯胺染色法能快速地检测山茶花粉的生活力.实验结果表明,两种花粉生活力随着贮藏时间的增加呈逐渐下降的趋势.花朵的开放程度对花粉的生活力影响不大,而贮藏条件对其影响显著：室温（13℃～25℃）下,两种山茶花粉贮藏12 d后生活力完全丧失;冷藏（2℃）条件下,盛开花粉贮藏26 d后生活力完全丧失,而初开花粉生活力完全丧失需要30 d.     

Germination capacity of Thekopsora areolata aeciospores and the effect of cone rusts on seeds of Picea abies

Mature Norway spruce (Picea abies) cones of different ages and colonized by Thekopsora areolata were collected in northern Finland 2009–2010. The germination capacity of aeciospores collected from intact aecia was measured on water agar and compared across cone age. Seed formation was investigated in healthy cones and those infected by T. areolata, Chrysomyxa pirolata, Chrysomyxa ledi, and seed germination was also measured for healthy cones and those infected by T. areolata. Unsporulated aecia of T. areolata occurred in 0- to 4-year-old cones. Aeciospores from current-year cones did not germinate and the germination capacity was significantly higher in one- to three-year-old cones than in older or current-year cones. However, a small number of aeciospores remained viable in four-year-old cones. Seed number and apparent health were significantly lower in cones infected by T. areolata and C. pirolata than in healthy cones or cones infected by C. ledi. Seed germination was significantly lower in cones infected with T. areolata compared to seeds from healthy cones. Our results suggest that infected cones more than one-year old continue to spread T. areolata for several years after the initial infection and fruiting, and thus promote the likelihood of epidemics and virulence of local outbreaks. Although cones infected by T. areolata and C. pirolata form significantly fewer seeds and of diminished viability, C. ledi does not appear to affect seed formation and health in Norway spruce. We recommend all rust-infected cones to be removed from orchards to improve stand health, reduce the risk of local outbreaks, and thereby increase the production and quality of Norway spruce seed.     

油松等常用林木种子贮藏有效年限的试验

选择辽宁省林业厅草河口林子种子库,结合生产需要,对油松等１０种常用造林、绿化树种的种子,在特定的环境条件下进行了贮藏试验。经多年试验观测,得出各树种种子保持生活力的有效年限;总结出种子含水量、环境温度、密封贮藏与种子贮藏寿命的关系。文中所得数据对种子贮藏时,确定最优技术组合、降低成本、提高效益具有一定参考价值。     

NaCl胁迫对白蜡种子生理特性的影响

为了给盐碱地造林树种选择提供依据,以采自秦皇岛和保定的白蜡种子为试材,采用不同浓度的NaCl胁迫处理,研究了其萌发过程中发芽率、细胞膜透性、保护酶活性、丙二醛MDA的变化,结果表明:(1)随着NaCl胁迫浓度的增加,两地白蜡种子发芽率均呈现逐渐降低的变化趋势,秦皇岛各处理的白蜡种子发芽率分别比对照降低了8.9%、52.6%、56.3%、61.6%、87.9%、91.1%,而保定的白蜡种子分别比对照降低20.2%、56.2%、68.7%、86.5%、89.9%、100.0%;(2)随着浓度的升高,种子的相对电导值、K+、Na+渗透率升高,种子的SOD酶活性降低,MDA含量增加,NaCl胁迫浓度越高,种子所受到的伤害越深;(3)0.20%浓度的NaCl胁迫对白蜡种子萌发影响不大。对于不同种源的白蜡种子,秦皇岛的白蜡种子抗盐性要优于保定的白蜡种子。     

不同温度、时间层积处理对北美鹅掌楸种子发芽影响

通过7种不同温度、不同时间的层积处理研究其对北美鹅掌楸种子发芽的影响。结果表明：低温层积处理能显著促进北关鹅掌楸的种子萌发。在2℃、层积处理时间为60d的条件下种子发芽效果最好，种子绝对发芽率为86．84％，发芽速度最快；在2～12℃变温层积处理56d的条件下，种子绝对发芽率为80.71％，种子发芽较快。在7℃，层积处理时间为30d的条件下种子发芽效果最差，种子绝对发芽率为62．29％。     

6种槭树属植物种子特性及其发芽试验

观察了6种槭树属植物种子的基本特性，同时进行了种子发芽试验，结果表明，6种槭树属植物种子形状多数近于球形或卵圆形，不同种子大小差异较大，毛果槭种子千粒重达321．80g，其余种子的千粒重集中于30-50g。6种槭树属植物种子均具有休眠的特性，采用低温湿沙贮藏可以解除其休眠，促进萌发，其发芽率可达70％以上。     

榆叶梅花粉贮藏及生活力的测定

对不同品种的榆叶梅新鲜花粉及贮藏后花粉的生活力进行测定的结果表明：品种不同，花粉生活力及耐贮力均不相同，其中单辨品种的生活力和耐贮力最强。榆叶梅花粉最适萌发培养基成分为15％蔗糖 2％琼脂。花粉的适宜贮藏条件为0-4℃低温黑暗条件。     

银杏种子黄酮与内酯含量变化

以银杏4个品种（马铃5号、马铃9号、金坠13号、金坠17号）的种子为试验材料,对不同时期银杏种子中的黄酮、内酯含量变化进行了系统研究。结果表明：不同品种间变化规律表现出相似性。在种子发育及采后层积过程中,黄酮含量呈现“减－增－减”的趋势。内酯的含量变化均为前期含量先减少,9月20日基本达到稳定状态,2月20日又呈下降趋势。     

亮叶木莲种子贮藏及萌发特性研究

研究依据国家林木种子检验技术规程,以采集于云南大围山国家级自然保护区的亮叶木莲 （Manglietia lucida）种子为试验材料,采用数显游标卡尺与电子天平秤测定种子纵径、横径、厚度（短轴 直径）以及千粒质量,并通过设置不同的种子贮藏方法、温度、光照和 GA3 浓度及浸种时间等处理对亮 叶木莲种子贮藏及萌发特性进行研究。研究结果表明：（1）亮叶木莲聚合果为卵球形,种子平均纵径为 7.83 mm、平均横径5.87 mm、平均厚度（短轴直径）3.08 mm,变异系数为11.97%~14.38%;千粒质量 为 59.92 g,变异系数为 4.16%;（ 2）种子萌发经历了“缓慢期—快速期—缓慢期”3 个阶段,萌发进程为 20 d,平均发芽率为 84.6%;（ 3）不同温度对亮叶木莲种子萌发有显著影响（P ≤ 0.01）, 0 h 光照时间对 种子萌发的影响与其他处理间均存在极显著差异（P ≤ 0.01）; 2 000 mg·L-1GA3 浓度处理对种子萌发的 影响与其他处理间具有极显著差异（P ≤ 0.01）;（ 4）亮叶木莲种子在 4 种贮藏方法中随着贮藏时间延长, 种子发芽率均呈下降趋势。综合以上各指标,亮叶木莲种子宜随采随播。种子萌发处理以温度 25℃、光 照时间 12~16 h,GA3 浓度 1 000 mg·L-1,浸种时间 24 h 为宜。     

遮荫下2种热带树苗叶片光合特性和抗氧化酶系统对自然降温的响应

选取 2种遮荫条件下 (8%、2 5 %全光照 )西双版纳地区热带雨林上层树种滇南红厚壳和中层树种玉蕊的幼苗 ,测定了雨季末自然降温过程中 2种植物叶片光合特性、抗氧化酶 (SOD、CAT、APX)活性、丙二醛 (MDA)含量的变化。研究结果表明 :低温使 2种植物单位面积叶绿素含量和净光合速率明显下降 ,生长在中等光强下的幼苗比低光强下的幼苗下降的比率大 ,滇南红厚壳比玉蕊下降的比率大。在降温初期 ,即从 10月到 12月初 ,2种光强下 2种植物SOD和APX活性上升 ,CAT活性出现波动 ,黎明光化学效率和MDA含量基本没有变化 ,光合机构没有受到氧化破坏。 12月末 ,中等光强下滇南红厚壳黎明光化学效率降低 ,SOD和APX活性有所下降 ,MDA含量显著上升 ;而低光强下的滇南红厚壳和 2种光强下玉蕊SOD和APX活性仍在上升 ,MDA含量变化较小。这表明 ,2种光强下 2种热带树苗是以不同的方式响应自然降温 ,低温对中等光强下的植物比低光强下的影响大 ,上层树种滇南红厚壳受到的影响比中层树种玉蕊大。同时 ,根据降温过程中抗氧化酶活性和MDA含量的变化 ,大致可将西双版纳热带雨林幼苗对低温的响应分为 2个阶段 ,即第 1阶段为低温适应阶段 ,抗氧化酶活性上升 ,光合机构没有受到明显的氧化破坏 ;第 2阶段 ,中等光强下滇南红厚壳抗氧化酶     

刺五加种子采收和催芽处理

介绍了刺五加种子采收过程及贮藏要点。在种子贮藏前经适当处理后,出苗率达80%左右。     

从种苗利用看广东林业的发展

文章总结分析了广东省1975~2005年间林木种苗生产的基本情况,以及林木种苗资源开发利用在广东林业建设中发挥的重要作用。并指出在新的发展阶段要继续重视种质资源开发,进一步加强种苗工作,全面推进种苗事业发展,为全省林业建设和国土绿化做出新的贡献。