Effect of water-spray cooling treatment in a Douglas-fir seed orchard on seed germination

Overhead-cooling treatment used to delay flowering produced non-significant effects on germination capacity, germination rate, germination value, and abnormal germination of seeds from a 13-year-old Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] seedling seed orchard. The percentage of variation accounted for by cooling treatment ranged from 0.0 to 1.0%. In contrast, variation among trees within treatments ranged from 28 to 46%. These effects were significant, indicating that each tree has an individual germination pattern. The temporal delay of reproductive phenology caused by temperature manipulation as a result of the cooling treatment was judged to be within the species' biological limits.     

Effects of seed moisture content,stratification and sowing date on the germination of Corylus avellana seeds

For Corylus avellana, pericarp permeability,seed desiccation tolerance, and the effect of warm and cold moist stratification combinations on germination and of outdoor sowing date on dormancy breaking and seedling emergence were investigated. Seeds with(intact fruit nut)and without the pericarp were subjected to an imbibition test, and water uptake was measured. After nuts had been stored for 5 months at 3–5℃, seeds and desiccated seeds were cold-stratified at 3–5 ℃(for 0, 1, 2 or 3 months),then tested for germination. Nuts were warm-stratified at 20–25℃(for 0, 1 or 2 months), then cold-stratified(for 0,1, 2 or 3 months) and tested for seed germination. The nuts were sown outdoors on three dates in the same year of their collection: 15 September(immediately after collection), 2 November, and 17 December, and emerged seedlings were counted the following spring. The pericarp was not a barrier to water uptake by the seed;however, the seeds imbibed water faster and had more mass when the pericarp was removed. Seeds tolerated desiccation;germinationpercentage was not reduced when seed moisture content was reduced to 8.71%. Germination of seeds without the pericarp(regardless of the moisture content) was the highest when the seeds were cold-stratified for 2 months.When seeds with the pericarp were tested for germination,2 months of warm stratification before a 2-month cold stratification maximized seed germination. For outdoor sowing of nuts, sowing date affected percentage of seedling emergence the following spring;early autumn sowing(immediately after collection) resulted in the best emergence.     

The effects of collection date and pre-storage treatment on the germination of blue oak acorns

Concern about poor natural regeneration of blue oak in California has prompted efforts to artificially regenerate this species. Two studies examined the best time to collect acorns and the effect various pre-storage treatments, including soaking and drying, have on germination. Results indicated that acorns can be successfully collected over a fairly wide interval, extending from late August until late October. Acorns from all harvest dates had high germination, as long as they were not allowed to dry out before storage. However, the earlier the acorns were collected, the earlier they tended to germinate. Soaking acorns for a day prior to storage had little effect. Drying acorns, however, reduced both the rate and amount of germination. A 10% reduction in moisture content resulted in almost 40% less total germination, and all acorns that lost 25% or more of their mositure failed to germinate during the 10-week test interval. To ensure good seed quality, blue oak acorns should be collected directly from tree branches and placed immediately in cold storage.     

疏枝对华北落叶松种子园结实的影响

对进入结实盛期的华北落叶松种子园,采取不同的疏枝方式,比较其对华北落叶松大小年现象及种子品质的影响。在同一个无性系中选择5个单株,分别对5个单株采取不同的疏枝措施,强度由小到大,分别去掉母树主枝的1/4、1/3、1/2、2/3,以不疏枝为对照,结果发现:随着疏枝强度的加大,第2年和第3年(小年)的结实量与疏枝强度呈正相关,种子品质也相应提高,说明通过人工疏枝措施,可降低明显的大小年现象,提升种子品质。     

Effect of harvest date,drying, short-term storage and freezing after chilling on the germination of rowan seeds

The effects of seed pretreatment and harvest date on the germination of European rowan (Sorbus aucuparia L) seeds were examined. In one experiment, seeds were subjected to drying, storage, soaking, warm and chilling treatments after harvesting in mid- and late August. In another experiment, fully imbibed (FI) seeds were given warm treatment for six weeks and then various durations of chilling (4?±?1°C) for up to 24 weeks. Thereafter, the seeds were adjusted to target moisture content of 35% and 30% or remained in the FI state and were then subjected to either subsequent chilling or freezing (?3°C) for up to 32 weeks. The treated seeds were allowed to germinate at a constant 15°C with 8 hours of lighting per day. Treatment effects were generally consistent for each harvest date. Seeds did not germinate unless they were chilled and germination rates were low unless the seeds were soaked. Warm treatment applied before chilling appeared to induce dormancy. The effect of storage varied with harvest date and storage treatment, with germination being highest for seeds harvested in late August. Mild freezing of ≥16 weeks duration following 16–24 weeks initial chilling resulted in >80% germination, more than could be achieved using chilling alone.     

Clonal variations in cone,seed and nut traits in a Pinus koraiensis seed orchard in Northeast China

Korean pine(Pinus koraiensis Siebold Zucc.)in Northeastern China has been genetically improved to increase seed yields in addition to timber.To assess seed yield variability and select highly productive clones,14 cone,seed and nut traits were measured and analyzed.Variance analysis showed that all clones were significantly different in various traits(P0.01).Phenotypic coefficients of variation and repeatability of traits ranged from 9.1 to34.4% and from 27.5 to 97.7%,respectively.Except for the cone layer and cone seed numbers,the other traits were positively or negatively correlated.Three principal components were identified.Seed and nut traits were the most important traits in the first principal component,and cone traits more important in the second.Using correlation and principal component analyses,cone number and other traits were selected to evaluate materials.Twenty-two clones were selected using a selection rate of 10% based on cone number independently or other combined traits.The genetic gain for different traits ranged from 6.2 to 24.3%.The selected elite clones can supply seedlings for reforestation and the selection method can provide a theoretical basis for selection in other conifer species.     

Effect of collection date on capsule moisture content and germination of Populus ciliata Wall. ex Royle from central Himalaya

Seed maturity indices of Populus ciliata were investigated in collections from Sukhatal and Bhowali. Across both seed sources, mean capsule size varied from 68.0±1.5 mm² to 72.0±0.9 mm², while mean number of capsules/100 grams varied from 268±8 to 295±12. Mean weight of 100 capsules varied from 25.0±1.4 g to 27.0±1.4 g. Weight of 100 capsules among sources and individual trees differed significantly (P < 0.05), while number of capsules/100 grams and weight of 100 capsules was negatively correlated (r² = 0.69). As capsules matured moisture content decreased from 83.2±1.1% to 54.3±0.3% at Sukhatal and from 77.7±0.4% to 46.4±0.3% at Bhowali. The optimum germination was at 58–60% moisture content. Maturation was related to capsule colour changes as well as moisture content. These parameters were judged to be good indicators of when to collect P. ciliata seeds.     

我国油松种子园开花结实与经营管理技术的研究概况

对油松种子园无性系开花习性、雌雄球花产量及其空间分布规律、球果与种子的产量及性状变异以及施肥、病虫害防治、去劣疏伐和修剪等经营管理技术措施的研究结果进行了系统分析,研究了我国油松种子园开花结实与经营管理技术的研究现状,可为我国油松种子园深化研究与经营管理提供参考。     

铝处理对茶条槭不同种源种子发芽指标的影响

以吉林市、大连市和尚志市3个种源的茶条槭种子作为试验材料,研究铝元素对茶条槭不同种源种子有关发芽指标的影响.结果表明:在3个铝质量浓度处理下,3个种源种子的胚轴长差异不明显;大连种源在2.0g·L-1铝质量浓度处理后种子发芽率和活力指数达到了最高,而尚志市种源在3.5g·L-1铝质量浓度处理后发芽率达到了最高;在5.0...     

Variation in reproductive phenology in a Pinus patula seed orchard and risk of genetic contamination from nearby natural stands

New Forests - Genetic variation in reproductive phenology among clones in a seed orchard affects the genetic efficiency of the orchard. Our objective was to evaluate genetic variation in...     

Effects of KNO3 pretreatment and temperature on seed germination of Sorbus pohuashanensis

We characterized the effects of KNO3 pretreatment and germination temperature on dormancy breaking and germination of mature mountain ash seeds. Seeds treated with KNO3 and germinated at 25 ℃ followed by 5 ℃ had significantly higher germination percentages and germination potentials (51% and 49%, respectively), compared with controls. These treated seeds also exhibited reduced germination initiation times (minimum of 48 days), and elevated germination rate indices (up to 97). The germination of seeds subjected to long-term cold storage (2 years at 0-5 ℃) was also significantly improved by 3 days of 4% KNO3 pretreatment before germinating under a variable temperature regimen (5 ℃ followed by 25 ℃, and followed by 5 ℃). Germination percentages and germination potentials for these cold-stored seeds reached 67% and 54%, respectively, and the germination rate index increased to 126.99. Pretreatment of mountain ash seeds with KNO3 represents a practical, effective, and pollution-free method for improving germination, and can be implemented easily within a variety of nursery settings.     

适时环剥对华北落叶松种子园中壮龄母树生长量及结实量的影响

在华北落叶松生长进入旺季、花芽分化前,对结实量低的中壮龄母树分系号进行不同方式的环剥,对母树的生长量及结实量会产生不同的效应。     

不同光照和温度处理对杉木种子萌发的影响

为探求不同光照和温度对杉木种子萌发的影响,该研究以杉木(Cunninghamia lanceolata)种子为试验对象,设置红光、蓝光、白光3个光照处理条件,每个光照处理条件设0,5,20μmol/(m2·s)3个光量梯度,并测量了萌发率、萌发指数和发芽势.结果表明:白光5μmol/(m2·s)、红光20μmol/(m...     

无性系、立地、郁闭度对杉木种子园产量和质量的影响

分析了无性系、立地、林分郁闭度等因子对杉木种子园产量和质量的影响，结果表明：无性系、坡向、郁闭度对杉木种子园产量有显著影响，对种子质量也有影响。杉木种子园宜选择阳坡、半阳坡，采用优质高产无性系建园；抓好密度和郁闭度管理，林分郁闭度以小于0.6为宜。     

Long term cone production and growth responses to crown management and gibberellin A4/7 treatment in a young western hemlock seed orchard

At age 5–6 years, rooted cuttings in a western hemlock (Tsuga heterophylla) clonal seed orchard received either a severe (ST) or moderate (MT) top pruning (upper 50 and 25% of live crown removed, respectively), or were left untopped (UT). Over the following 6 years, UT trees increased in height from 1.5 to 3.9 m, whereas through annual and biennial top and side pruning, MT trees grew to 2.2 m and ST trees were maintained at 2.0 m. Crown pruning had no effect on the subsequent annual production of seed or pollen cones. Spray applications of gibberellin A_4/7 in years 2 and 4 of the study increased 5-fold and 2-fold the percentage of trees producing a medium and greater crop, respectively, of seed and pollen cones in each year 3 and 5.     

浸泡和冷预处理对喜马拉雅长叶松不同种源种子萌发的作用

对喜马拉雅长叶松种子进行24小时GA3和H2O2浸泡预处理和15d的2-3℃低温预处理后,研究了在20℃,25℃和30℃萌发条件下,21个不同种源的喜马拉雅长叶松种子的萌发情况。结果表明,H2O2（1%v/v）和GA3（10mg/L）浸泡预处理,种子萌发率分别是82.39%和78.19%,而未经预处理的种子平均萌发率为70.79%。GA3和H2O2浸泡预处理分别使种子萌发时间缩短了8d和10d。在超过21天的20℃萌发条件下,湿冷处理提高了种子萌发率和缩短了萌发时间 而在25℃和30℃萌发条件下,总的萌发率未受到影响。喜马拉雅长叶松种子因缺少休眠而表现出很好的萌发,但是因为越来越多的造林项目需要大量的种子,播种预处理有利于提高种子萌发率和萌发速率,有助于满足种子需求。     

Effect of magnetic treatment on seed germination of loblolly pine (Pinus taeda L.)

Based on preliminary experiments, the speed of germination (SG) was in general increased for Pinus taeda L. seeds treated with a static magnetic field (B = 150 mT) for 10, 30 and 60 min. Negative impact was obtained for seeds treated with SMF for 24 h and 48 h. Mean germination time (MGT), the SG, and time required to obtain 10%, 25%, 50%, 75%, and 90% of seeds to germinate (T₁₀–T₉₀) were calculated. Results showed a reduction of the MGT and T₁₀–T₉₀ for seeds treated with SMF for 10, 30, and 60 min; therefore, the germination speed was increased. Among various magnetic treatments, loblolly pine seeds treated with S3 (SMF60 min) yielded the peak performance.     

Effect of thermal pretreatment on germination of seeds from different provenances of subalpine oriental spruce (Picea orientalis (L.) Link.) forest in Turkey

We examined the effect of thermal treatment at two temperatures (60 s of 90°C dry heat and 60 min in 40°C hot water) versus control conditions on the germination of oriental spruce (Picea orientalis (L.) Link.) seeds originating from different subalpine provenances. Cutting test results showed that there was wide variation (between 10% and 90%) in filled seed rates. The results revealed that highest germination yield was attained via the hot water treatment. The maximum germination percentages were observed in seeds from “tree 3” in the first tree collective of provenances 1 (85.33 ± 5.77 control; 88.67 ± 7.02 via the hot water treatment; 82.00 ± 10.58 via the dry heat treatment) and 3 (70.67 ± 17.24 control; 88.00 ± 4.00 via the hot water treatment; 86.67 ± 11.37 via the dry heat treatment). The mean germination percentages were significantly different (p-value < .05): percentage values were 32.57% in provenance 1, 23.22% in provenance 3, 12.25% in provenance 4, and 2.82% in provenance 2. Mean germination time of seeds from different provenances and experiencing various pretreatments showed significant variation. The best pretreatment increase in germination rates was achieved via the wet heat method (60 min in 40°C hot water).     

云杉、落叶松等树种种子发芽对水分胁迫的反应

云杉、落叶松等树种种子发芽对水分胁迫的反应马常耕，王建华关键词云杉，落叶松，聚乙二醇，水分胁迫聚乙二醇（ＰＥＧ）是一种中性长链多聚化合物，可配成预定水势溶液，用来模拟土壤的自然水势，造成水分胁迫，以研究植物对水分胁迫的反应［１，２］，揭示其抗旱能力。...