长白落叶松胚性愈伤组织诱导及体细胞胚胎发生

【目的】以长白落叶松的未成熟合子胚为外植体,进行胚性愈伤组织的诱导、增殖培养及体细胞胚胎发生的相关研究,揭示影响长白落叶松胚性愈伤组织诱导的关键因素,并探讨继代培养过程中添加不同种类、浓度的生长调节剂对胚性愈伤组织增殖及体胚发生的影响。【方法】采集长白落叶松3个家系优良单株的种子,诱导胚性愈伤组织,比较外植体采集时间、家系、2,4-D浓度及基本培养基对胚性愈伤组织诱导的影响。诱导出的胚性愈伤组织继代于含不同种类、浓度生长调节剂的增殖培养基,通过体胚发生途径获得体细胞胚。选取发育正常的体胚进行萌发,待体胚生根后移栽。【结果】不同时间采集的未成熟合子胚,其胚性愈伤组织诱导率存在较大差别,授粉后63天的合子胚诱导率为5.61%,授粉后70天诱导率为22.35%,而授粉后80天未诱导出胚性愈伤组织;‘长77-22’、‘长77-37’和‘长73-50’3个家系胚性愈伤组织的平均诱导率分别为6.69%,11.17%和3.11%;2,4-D浓度对长白落叶松胚性愈伤组织诱导具有一定影响,在一定范围内胚性愈伤组织的诱导率会随2,4-D浓度升高而升高,当其浓度为1.5 mg·L~(-1)时胚性愈伤组织的诱导率最高,达到11.11%,而当2,4-D浓度超过1.5 mg·L~(-1)时,胚性愈伤组织的诱导率则开始下降;BM,MS,S培养基均能诱导出胚性愈伤组织,其中,BM培养基的诱导率最高,S培养基的诱导率次之,MS培养基的诱导率最低。胚性愈伤组织在含2,4-D 0.3 mg·L~(-1)、6-BA0.1 mg·L~(-1)及KT 0.1 mg·L~(-1)的BM培养基上增殖15天可获得相对较多的胚性愈伤组织,增殖率为345.93%;在含2,4-D 1.5 mg·L~(-1)、6-BA 0.5 mg·L~(-1)及KT 0.5 mg·L~(-1)的BM培养基上培养14天,再经诱导可获得较多的体细胞胚胎,每克愈伤组织平均诱导179.87个体胚,并且这些体胚的萌发率及植株再生率相对较高,分别为75.00%,66.67%;再生植株移栽成活率为27.08%。【结论】不同长白落叶松家系的胚性愈伤组织诱导率不同,散粉后70天的合子胚适合诱导胚性愈伤组织,基本培养基为BM,添加2,4-D 1.5 mg·L~(-1)。胚性愈伤组织长期继代在含高浓度生长调节剂的培养基上易丧失胚性,且增殖速度慢,但体胚的发生量及萌发率相对较高;适当降低生长调节剂浓度利于愈伤组织保持胚性及增殖,但体胚的发生量及体胚的萌发率有所下降;当培养基中生长调节剂浓度较低时,不利于愈伤组织的增殖,但仍能使其胚性长期保持;采用浓度为0.5 mg·L~(-1)的NAA代替0.15 mg·L~(-1)的2,4-D有助于胚性愈伤组织的增殖,并能在一定程度上提高体胚的萌发率。因此,可根据不同阶段的培养目的,选择添加不同种类和浓度生长调节剂的增殖培养基进行继代。     

挪威云杉及杂种落叶松稳定胚性细胞系及体胚再生系统的建立

本文报道了挪威云杉(Picea abies)和杂种落叶松(Larix deciduas× L. kaempferi)人工授粉种子诱导胚性细胞系及植株的再生.挪威云杉在德国Saxon Ore 山区被选为对空气污染有抗性的树种并种植在位于Waldsieversdorf的林木遗传育种研究所的种植园中.对挪威云杉测试了几个不同亲本组合的种子形成胚性细胞系的能力.这些云杉种子于1992-01采收,含有干燥的成熟合子胚.作为对照,相同的亲本组合云杉种子于1993-08和1998-08采收,合子胚处于成熟中.杂种落叶松则只有一个人工授粉组合,大田试验证实幼苗生长良好.分别于1995和1996年采收含有未成熟合子胚的未成熟种子.诱导愈伤形成用附加细胞分裂素(激动素和/或BAP)和生长素(NAA, 2,4-D)及有机氮源(水解酪蛋白和谷氨酰胺)的标准培养基(SPE和MSG),于黑暗下培养.尽管在建立培养体系后5～12周产生了大量胚性愈伤组织,诱导率超过25%,但1 a后只有超过1%的胚性愈伤组织稳定生长.挪威云杉稳定胚性细胞系的数量与成熟合子胚的采收季节及建立细胞系的时间(8月或1月)无关,但在8月收获的合子胚在挪威云杉5～12周后胚性愈伤组织诱导率要高些,然而能在悬浮培养中生长及随后成熟体胚能顺利再生植株的稳定胚性细胞系的数量有限.挪威云杉体胚未充分发育的根影响其移栽到土壤中的成活率.在建立的12个细胞系中只有一个在干燥保存后能从体胚再生正常植株.同时考察了影响挪威云杉形成成熟体胚的因素,如用PEG4 000(7.5%)及ABA[8mg·L-1(30.26μmol)-1]处理及ABA灭菌方式(高温高压灭菌或过滤灭菌)对成熟体胚形成的影响.总体来说,过滤灭菌的ABA增加了成熟体胚的数量.营养培养基中用淀粉部分取代蔗糖只导致2个细胞系中的一个增加了成熟体胚的数量.1995和1996年对人工授粉杂种落叶松合子胚发育与自然授粉(不套授粉袋)的相比较,发现人工授粉袋的使用延迟了合子胚的发育.我们的实验中成熟合子胚没有形成胚性细胞系,只有未成熟合子胚形成了胚性细胞系.1995年用落叶松未成熟合子胚建立的胚性细胞系没有形成体胚,而1996年建立的4个胚性细胞系得到了可以移栽到温室中的再生植株.1.5 a的连续继代培养以后,大多数的杂种落叶松和挪威云杉的胚性细胞系的再生能力都下降.导致这种现象可能有多种原因包括培养物的老化以及出现难以检测到的内生细菌.尽管一组实验从最初培养即用了抗生素,但没有收效.因此目前只得到少量的稳定胚性细胞系(<5%),长期继代后丧失再生能力及无法成功移栽到土壤都是植株再生的重要的限制因素,有待进一步研究克服这些困难.     

刺槐未成熟合子胚的体细胞胚胎发生和植株再生

以刺槐不同胚龄的未成熟合子胚为外植体,采用混合正交试验设计,研究幼胚胚龄和不同外源激素种类及质量浓度对刺槐胚性愈伤组织的诱导和体细胞胚分化、萌发的影响.结果表明:开花后8周(55天左右)是胚性愈伤组织和体胚诱导的最佳外植体取材时期;MS+2,4-D 5.0 mg·L-1 +BA0.5 mg·L-1是诱导胚性愈伤组织的最佳培养基,出愈率最高为95.42％±0.02％;MS +NAA0.5 mg·L-1 +BA0.5 mg·L-1+谷氨酰胺250 mg·L-1+水解酪蛋白500 mg·L-1是体细胞胚诱导和分化的最佳培养基,直接体细胞胚发生率最高为92.40％±0.12％,通过愈伤组织诱导体细胞胚发生的频率最高为90.73％ ±0.49％.一旦形成球形胚,将培养物转接到不含任何生长调节剂的MS培养基上,体细胞胚经成熟萌发可进一步形成完整小植株.     

黑松未成熟胚的体细胞胚胎发生和植株再生

以未成熟合子胚为外植体,建立黑松体细胞胚胎发生和植株再生体系。研究基本培养基、2,4-D和6-BA对胚性愈伤组织诱导的影响,探讨ABA和PEG对体细胞胚成熟及植株再生的影响。结果表明:在添加4mg·L-12,4-D+2mg·L-16-BA的DCR培养基上胚性愈伤组织诱导率为3.33%;在添加30mg·L-1ABA+25g·L-1PEG的培养基DCR上,每克愈伤组织体细胞胚数量达72个,体细胞胚的萌发率为63.8%、植株转化率为43.5%,高质量的黑松体胚能提高体胚萌发率和植株转化率,再生植株1个月移栽成活率为50%。该研究可为抗病黑松的快速大规模繁殖提供一条新途径。     

长白落叶松愈伤组织及不定芽的诱导

以长白落叶松成熟合子胚为研究对象,从外植体消毒方式及愈伤组织与不定芽诱导的适宜培养基、激素组合和配比的选取等方面着手,进行长白落叶松愈伤组织及不定芽诱导的研究。结果表明:先用4%NaClO消毒去皮种子15 min后,再用0.5%NaClO消毒胚2 min为长白落叶松成熟合子胚的最佳消毒方法;BM为愈伤组织诱导的最适培养基;当BM+2.0 mg·L^-1 TDZ时,愈伤组织诱导率最高,为89%;BM+1.5 mg·L^-1 TDZ时,不定芽诱导率最高,为80.0%。     

麦芽糖、NAA及ABA对华北落叶松体细胞胚成熟及生根的影响

研究了麦芽糖、NAA、ABA对华北落叶松体细胞胚发生及体细胞胚根发生和再生完整植株的影响。结果表明 :在胚性愈伤组织继代、增殖过程中 ,以 0 5mg·L- 1 的NAA代替 2 ,4 -D后 ,有利于体细胞胚的成熟和根发生。在ABA 16mg·L- 1 时 ,产生的华北落叶松体细胞胚 ,能够再生良好植株 ,ABA大于 2 0mg·L- 1 时对体细胞胚根的发育不利。在含 3%麦芽糖、4 %PEG4 0 0 0活性炭 1g·L- 1 的成熟培养基上 ,华北落叶松每克愈伤组织子叶胚达 10 6 7个 ,生根率达 5 7 89% ;显著地提高了成熟体细胞胚及其根的质量。     

地被菊间接体细胞胚发生途径的转基因受体体系的研究

采用三步培养法建立了地被菊花品种‘玉人面'间接体细胞胚发生途径的转基因受体体系.试验以地被菊花品种‘玉人面'茎段(节间)为外植体,研究了生长调节剂、光照强度等因子对其间接体细胞胚诱导和分化的影响,同时进行了抗生素敏感性试验.结果表明:胚性愈伤组织诱导培养基为MS KT 2.0 mg·L-1 2,4-D 2.0 mg·L-1 NAA 0.5 mg·L-1,诱导15 d后,将获得的黄绿色致密颗粒状胚性愈伤组织转入胚性愈伤组织分化培养基MS KT 2.0 mg·L-1 2,4-D 1.0 mg·L-1 NAA 0.5 mg·L-1中,诱导15 d后再转入MS KT 2.0 mg·L-1 NAA 0.5 mg·L-1的分化培养基中培养20 d,光照强度为1 000～2 000 lx,胚性愈伤组织诱导率、分化率分别为95.3%、92.7%,平均每个外植体分化的芽数为17.8个,获得的再生芽的稳定性为99.5%.抗生素敏感性试验表明:地被菊花品种‘玉人面'间接体细胞胚发生途径的转基因受体体系中,卡那霉素选择压为20 mg·L-1;头孢霉素在胚性愈伤组织诱导时的选择压为300 mg·L-1,在胚性愈伤组织分化培养时选择压为100 mg·L-1.     

华北落叶松胚性愈伤组织诱导影响因子的研究

以成熟合子胚为外植体,用完全随机、正交设计等试验方法加之组培技术来研究影响华北落叶松(Larix princi-pis-rupprechtii)胚性愈伤组织诱导的几种主要因子。结果表明:诱导胚性愈伤组织过程中的最佳灭菌方式为2%Na-ClO灭菌30 min,剥皮、去胚乳处理。其中污染率和NaClO的灭菌时间呈负相关:NaClO灭菌时间越长,污染率越低。诱导胚性愈伤组织的最佳琼脂浓度为4 g·L-1,且过高和过低的琼脂浓度不仅降低了其诱导率,提高了愈伤组织的褐化水平,也影响了外植体的发育形态。外源激素的正交试验结果表明:2,4-D是主要影响因子,对诱导率的影响显著,其次是KT,最后是6-BA。最佳的植物外源激素配比是2,4-D 1.8 mg·L-1+6-BA 0.3 mg·L-1+KT 0.3 mg·L-1。     

桃幼胚及幼胚子叶再生的研究

以玉露桃和湖景蜜露桃幼胚及幼胚子叶为试材,研究基本培养基类型、激素、损伤方式等因素对再生的影响。结果表明:培养基是影响幼胚诱导愈伤组织的最重要因素,MS适合供试材料诱导愈伤组织;激素诱导愈伤组织因品种而异,NAA1.0mg·L-1对45d、0.5mg·L-1对55d玉露,BA0.5mg·L-1对55d湖景蜜露效果较好,在试验浓度范围内2,4-D对供试幼胚均无明显效果;幼胚的发育状态是影响诱导愈伤组织的另一因素,玉露桃45d愈伤组织诱导率最高,达96.6%,而55d诱导率为81.6%。愈伤组织可在MS 0.05mg·L-1NAA 1.0mg·L-1BA培养基上分化成芽,再生芽在1/2MS 1.0mg·L-1IBA培养基上生根。幼胚子叶不定芽再生培养基的激素配比为NAA0.50mg·L-1 BA10.0mg·L-1、NAA0.05mg·L-1 TDZ3.0mg·L-1;带胚芽子叶纵向刻伤再生率高;不定梢(芽)在1/2MS 2%蔗糖 7.5g·L-1琼脂 IBA1.0mg·L-1 Ad20mg·L-1的培养基上能生根。     

杂种落叶松胚性愈伤组织诱导的研究

以杂种落叶松兴7×日77-2、日12×兴9、日3×兴9、日3×兴2、日5×兴9未成熟合子胚为外植体,初步建立杂种落叶松胚性愈伤组织诱导体系。结果表明:不同杂种落叶松在不同培养基和蔗糖浓度下的诱导情况不尽相同,基本培养基中MSG与MS培养基的诱导效果比较好,激素浓度的差异对杂种落叶松也有影响,2,4-D浓度为2.0 mg/L时,诱导率高,蔗糖浓度为30 g/L能诱导出胚性愈伤组织,高浓度的蔗糖反而抑制了胚性愈伤的形成。ABA分别为0、5、10、20、30 mg/L的5个处理中,除对照及ABA30 mg/L时没有诱导出体细胞胚,其他试验组均有一定数量的体细胞胚,但诱导率较低。几种杂种落叶松胚性愈伤组织诱导最适合的采样时间是7月中旬。     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Decomposition and nutrient loss from prunings of different contour hedgerow species in tea plantations in the sloping highlands of Sri Lanka

Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week⁻¹ for leaves and from 0.0225 to 0.0633 week⁻¹ for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > Tithonia ≥ Euphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient enrichment capacity and slower decomposition rates which would minimize leaching losses. This revised version was published online in June 2006 with corrections to the Cover Date.     

Growth of Phlebiopsis gigantea in wood of seven conifer species

Heterobasidion parviporum and Heterobasidion annosum are widely distributed root‐rot fungi that infect conifers throughout Europe. Infection of conifer stumps by spores of these pathogens can be controlled by treating fresh stumps with a competing non‐pathogenic fungus, Phlebiopsis gigantea. In this study, growth of three Latvian strains of P. gigantea and the biological control agent ‘Rotstop’ strain was evaluated in stem pieces of Norway spruce, Scots pine, lodgepole pine, Douglas‐fir, Weymouth pine, Siberian larch and Sitka spruce. The growth rates of one H. parviporum and one H. annosum isolate were also measured in the same stem pieces. The growth rate of P. gigantea varied greatly in wood of different conifer species. It was higher in the three pine species, lower in Norway spruce and lowest in Sitka spruce and Siberian larch, and in Douglas‐fir, this fungus did not grow. The largest area of wood occupied by P. gigantea was in lodgepole pine. Growth of Latvian isolates of P. gigantea in the wood of Pinus and Picea species was comparable to that of the Rotstop isolate. Consequently, stump treatment with local P. gigantea isolates should be recommended. However, our results suggest that Douglas‐fir stump treatment against Heterobasidion by P. gigantea may be ineffective and other stump treatment methods should be considered.     

Effects of Seed Weight and Seed Type on Early Seedling Growth of Pinus sylvestris under Harsh and Optimal Conditions

The effects of seed weight and seed type on seedling growth of Pinus sylvestris (L.) were studied by seeding individually weighed orchard and stand seed in different mixtures under harsh (direct seeding in field) and optimal (seeding in nursery) conditions. In the nursery experiment an increase in the seed weight from 3 to 7 mg increased the seedling height by 10-27% and total weight by 27-113%, and decreased the height/diameter ratio by 5-6% after 2 yrs. With elimination of seed weight effects, orchard seedlings were 2% taller than stand seedlings in year 2. Without elimination of seed weight effects, orchard seedlings were 7-13% taller. In the field experiment an increase in the seed weight from 3 to 7 mg increased seedling height by 18-65%, stem volume by 81-274% and the number of top-buds by 23-34% in year 5. After elimination of seed weight effects, orchard seedlings were 7-13% taller than stand seedlings and without elimination of seed weight effects 20-21% taller after 5 yrs. Even after elimination of both seed weight and genetic effects orchard seedlings were 3-9% larger than stand seedlings in the field experiment. In conclusion, the influence of seed weight and seed type on growth traits and slenderness is highly significant and the influence seems to be greater in harsh conditions.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Potential to harness superior nutritional qualities of exotic baobabs if local adaptation can be conferred through grafting

Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral contents and B₁ and B₂ vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B₁ 88 mg 100 g⁻¹, B₂ 187 mg 100 g⁻¹, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations.     

Modelling of adequate pretwist for obtaining straight timber

Abstract

Wood in general and wooden studs in particular are often distorted owing to uneven shrinkage during the drying process in the sawmill. Twist is often the most detrimental of all types of distortion, and it is caused by spiral grain in combination with variations in moisture content. For sawmills, the objective is to produce dried, straight boards, and one method of dealing with boards with excessive spiral grain is to sort them out and then dry them in a pretwisted position to obtain straight boards after drying. A model using the finite element (FE) method for the simulation of drying twist distortions was first calibrated against laboratory experiments in which boards were dried with and without restraints and pretwists. After the calibration, the FE results were compared with industrial test results for boards that were dried without restraints or with restraints with zero pretwist, i.e. straight restraints. The FE model used an elastic–ideally plastic material model to obtain permanent deformations. The calibration was to set the yield stresses so that there was a good match between FE results and results from the laboratory experiments. The comparison between the industrial test results and the FE results showed that the FE model is capable of realistic simulations of drying boards with and without restraints and presumably also pretwists.