Height growth of Korean pine plantation sapling in Benxi, Liaoning Province, China

The height growth of Korean pine plantation was investigated for different ages of saplings in Benxi city of the eastern Liaoning, China. The sapling and seedling age were determined by branch annuals. Results show that the mean height of third- to eight-year Korean pines ranges from 13.31 cm to 111.73 cm and only 19.4% of the saplings reached the height above 130 cm. The height (Y) of eight-year-old Korean pine increases linearly with the increment of ground stem (x) (Y=3.1x+35.15). The relation between height and age can be described by an exponential equation. The second year after planting of the Korean pine is considered as the key period of Korean pine growth really adapting to the local environment; plantation management should be strengthened in this year. The Korean pine seedlings need two years to adapt to the local environment, thus early care and management should be taken in the second year.     

Variation analysis of growth traits of four poplar clones under different water and fertilizer management

To determine appropriate quantities of water and fertilizer required for early growth of hybrid poplar cuttings,we recorded the growth traits of four clones grown under four factors(irrigation and nitrogen,phosphorus,and potassium fertilizers),each with four levels,using an orthogonal experimental design.A logistic model was used to estimate growth in height.The growth curves for tree height were sigmoid,and the model R^2 values were greater than 0.9,which indicated that the fit was highly significant.ANOVA results for tree height and basal diameter indicated that all sources of variance showed significant differences(p<0.001).The average tree height and basal diameter for all the four clones under the different treatments ranged from 155.39 to 235.04 cm,and from 13.71 to 17.42 mm,respectively.A highly positive correlation between the extreme k value and tree height was observed,suggesting that the k value was an accurate estimation of tree height.For model parameters,the earliest average time point for the onset of the rapid growth period of poplar clones was 131 d,and the highest average increment in tree height during the rapid growth period was 138.78 cm.The highest average tree height for all clones under each factor was 219,210.51,200,and 201 cm when treated with either 1200 mL of water applied every third day,3 g of nitrogen,0 g of phosphorus,or 0 g of potassium,respectively.The most suitable treatment for the early growth of hybrid poplar cuttings,as suggested by the developed logistic model,was 1200 mL of water applied every third day and three applications of 1 g nitrogen(in the form of CH4N2O).     

APPLICATION AND EFFECTS OF RARE-EARTH ON SEEDLINGS

In order to improve the quality of seedlings and economic benefits,rare--earth experiments were carried out on eleven seedling-age-types of four silvicultral treespecies.Some indexes such as the increment,biomass and chlorophyl content weredetermined.The results showed that rare-earth can improve the growth in height anddiameter,increase the bioprductivity and increase the mean benefit by887766.29 yuan/hm~2.It is an effective method to improve the quality of seedlings for the characters such as lowcost and easy grasping.And the method can be widely used in seedling.     

Genetic variation of height growth rhythm between clones of Larix kaempferi × L. gmelini based on logistic models

Fifty-three larch interspecific hybrid clones(Larix kaempferi × L.gmelini) and their parent clones were used for growth curve analysis of height variations.The growth curves of the 55 clones were 'S'-shaped and 36 exhibited similar curves as the male parent.The coefficients of the logistic models were higher than 0.943,indicating that our results were effective in the simulation of the growth curves.ANOVA analysis showed significant differences in height of different clones (P\0.01).Average date of maximum height growth was Day 173,and average duration of rapid growth lasted for 50 days.Annual average increase in height was 9.7cm d~(-1) and daily average increase was 0.2 cm.The ratio of GR to the total annual increase in height ranged from 51.2 to 68.8%,with the average being 59.8%.There was a positive correlation between k values and plant heights which benefited from the evaluation of early plant height.There was also a positive correlation between GR(growth stage),GD(plant height) and annual increase in height.These results are informative to the evaluation of the elite clone selection and provide a theoretical basis for breeding and management.     

珍贵用材树种柏木轻基质容器育苗试验研究

This paper dealt with an experiment on container seedlings culture with nonwoven and light medium for Cupressus funebris, a precious timber tree species, through orthogonal design. The effects of container height, quantities of controlled release fertilizer and the medium proportion on seedling quality of Cupressus funebri were studied. The results showed that seedling height, ground diamater, divarication number and the ratio of seedling height to ground diameter of Cupressus funebri were significantly affected by the height of container and the quantities of controlled release fertilizer, and little influenced by the medium proportion. There were significant different influences on seedling growth among different treatment combinations. The treatment combination No.9 was the best one with averaged seedling height, ground diamater, divarication number and the ratio of seedling height to ground diameter of 21.75 cm, 0.271 cm, 10.7 branches and 80.29, respectively. The treatment combination of No.6, No.3 and No. 5 were relatively good treatment. The length of seedling container of nonwoven with diameter of 5 cm for Cupressus funebris, could be selected as 10—12 cm. The quantities of controlled release fertilizer of 3 kg·m^-3 and the seedlings density of 215—220 plants·m^-2 could be the optimal for nursing seedling with high quality. The costs of medium proportion on several container seedlings base of Zhejiang Province were compared and analyzed.     

A basal area increment model for individual trees in mixed continuous cover forests in Iranian Caspian forests

The aim of this study was to develop and test a new basal area growth model in mixed species continuous cover forests in northern Iran.Weanalyzed 421 core samples from 6 main species in the forest area to develop our growth model.In each plot,we measured variables such as total tree height(m),diameter at breast height(DBH)(cm)and basal area of larger trees as cumulative basal areas of trees(GCUM)ofDBH[5 cm.The empirical data were analyzed using regression analysis.There was a statistically significant nonlinear function between the annual basal area increment,as the dependent variable,and the basal area of the individual trees and competition as explanatory variables.Reference area from the largest trees,was circular plot with area of 0.1 ha.GCUM was estimated for trees of DBH>5 cm.Furthermore,we investigated the dependencies of diameter growth of different species on stand density at different levels of competition,and diameter development of individual trees through time.The results indicate that competition caused by larger neighborhood trees has a negative effect on growth.In addition,the maximum diameter increment is affected by competition level.Therefore,the maximum diameter increment of species occurs when the trees are about 35–40 cm in dense-forest(40 to 0 m^2 per ha)and when the trees are about 60 to 70 cm in very dense forest(60 to 0 m^2 per ha)which is more likely to Caspian natural forests with high level density due to uneven-aged composition of stands.     

Early evaluation of growth traits of Larix kaempferi clones

Early selection is an important method to shorten the breeding cycle for tree species, which may differ in the time for early selection.To evaluate the early selected time for Larix kaempferi, tree height and diameter at breast height of 57 L.kaempferi clones were measured over many different growth years.The results indicated that, except for age × clone interaction for diameter at breast height(P = 0.741), there were significant differences among all variation sources(P 0.01).The coefficient of phenotypic variation ranged from 14.89 to 35.65%for height and from 19.17 to 23.86% for diameter at breast height in different growth years.The repeatability of height and of diameter at breast height among clones was high,ranging from 0.6181 to 0.8531(height) and from 0.8443 to0.8497(diameter at breast height), in different growth years.There were significant positive correlations between all pairs of growth traits except between height in the 2 nd growth year and height in the 30 th growth year; and between height in the 2 nd growth year × diameter at breast height in the 30 th growth year.With a comprehensive evaluation method and a selection ratio of 10%, L65,L1, L62, L9, L15, and L78 were selected as excellent clones in the 30 th growth year.Their average values of height and diameter at breast height were 9.81 and 16.57%higher than the overall average, representing genetic gains of 6.46 and 13.99%, respectively.This study provides a theoretical foundation for the genetic improvement of L.kaempferi.     

Influence of main site factors on Fraxinus mandshurica（Oleaceae） plantation

The investigation was carried out on 10-year-old plantation of Fraxinus mandshurica in Mao‘er Mountain Experimental Station of Northeast Forest University.tree height(H),diameter at breast height(D1.3) and the increment of tree height in 5 years (H5),the thickness of humus layer,as well as the soil moisture were measured for the plantation and the growth indexes(H,D1.3,H5) for different site conditions were analyzed.The results showedthat main site factors influencing the growth of Fraxinus mandshurica were soil moisture,gradient and location of siope in order.The growth of Fraxinus mandshurica was better on the middle-or up-slope site than on the down-slope site.Soil moisture and late frost caused by terrain are the main reasons that limit the growth of Fraxinus mandshurica plantation.     

Effects of precommercial thinning on growth parameters in Pinus nigra Arn. subsp. pallasiana(Lamb.) Holmboe stand

We investigated the effects of precommercial thinning(PCT) applied at different levels on the growth parameters of natural Anatolian black pine stand. The experimental site was located in the province of Isparta in southern Turkey. PCT was set up using a randomized complete block design with three replicates and three treatments(control, 2–2.5 m × 2–2.5 m and 3–3.5 m ×3–3.5 m spacing). The experimental plots were established in March 2014. At the end of the growing seasons for three years(2014–2016), growth parameters such as diameter, height and crown radius were measured. PCT was found to be significantly effective on diameter, height,individual tree basal area, and crown radius increment at the end of the third year(p 0.05). While diameter,individual tree basal area and crown radius increment increased with increasing PCT intensity, height increment was higher in control than PCT. Although the PCT treatments applied with 3–3.5 m spacing affected individual tree development positively, we need long-term results on wood quality and yield. According to the short-term results, it is thought that it is better to lower the standcloseness gradually, so, it may be advisable to apply PCT by 2–2.5 × 2–2.5 m spacing.     

Evaluation of early growth performance of 41 clones of teak(Tectona grandis Linn. f.) at four microsites in Purwakarta,Indonesia

Teak(Tectona grandis Linn. f.), one of the mostvalued tree species in the world, is slow-growing with a long period until it can be harvested;therefore, ensuring that only high-quality seedlings or clones are selected for planting is critical. The main objective was to determine performance and repeatability of selected clones in terms of growth and survival rates in different micro-environments. A 2-year clonal trial using 41 clones and a local seedling of teak as a control were grown at 4 microsites differing in spacing, soil fertility and alley crops to assess tree height, diameter and survival rate that was evaluated in Purwakarta, West Java, Indonesia using a randomized complete block design with four replicates of each clone at each microsite. Teak growth was influenced by clone(p < 0.01), microsite(p < 0.05) and clone 9 micrositeinteraction(p<0.01). The interaction clone 9 microsite resulted in several potential superior clones that differed in terms of growth rates at each microsite. On the basis of diameter only, superior clones(nos. 14, 18, 24, 30 and 37)were identified. Repeatability estimated was Rc2= 0.84 for diameter and Rc2= 0.77 for height. Growth performance of teak trees varied among microsites. Repeatability values for diameter and height characters were high. The effect of variable growth on each clone was influenced by genetic factors, environmental factors and the interaction of genetics 9 environment. Microsite significantly affected growth of teak clones. Clone 9 microsite interaction significantly affected growth of clones and led to the growth of superior clones at each microsite.     

秃杉苗高生长期划分的有序样本聚类分析

以秃杉苗高15d的净生长量为样本,采用有序样本聚类分析方法,将秃杉苗高生长过程划分为4个时期:出苗期(3月1日～5月31日)、幼苗期(6月1日～7月31日)、苗高速生期(8月1日～10月31日)、苗木生长后期(11月1日～11月30日),其中苗高速生期的高生长量占全年生长量的64%。根据各时期苗木生长的特点,提出了各时期的管理措施,为培育秃杉优质壮苗提供依据。     

福建柏苗高生长期划分的有序样本聚类分析

以福建柏苗高15 d净生长量为样本,采用有序样本聚类分析方法,将福建柏苗高生长过程划分为5个时期:出苗期为3月1~30日,幼苗期为4月1日~5月30日,速生前期为6月1~15日,速生期为6月16日~9月30日,生长后期为10月1日~12月30日。速生前期和速生期的净生长量只占全年总生长量的28.5%,而幼苗期、生长后期的净生长量分别占全年总生长量的30.0%、34.9%。因此结合福建柏的生理特性提出幼苗期、生长后期的管理措施,为培育福建柏优质壮苗提供依据。     

北抗1号杨苗期年高生长进程分析

利用Logistic方程对北抗1号杨苗期年高生长节律进行拟合，建立了数学模型：H=223．1／[1＋exp（3．34213-0．04392t）]，相关系数0．9923。并依此将整个生长过程分为前生长期、速生期、后生长期3个阶段，其中速生期（6月16日～8月16日，60d）苗高生长量占总生长量的57．76％。提高苗木质量，培育大苗壮苗应加强这一关键时期的田间管理。     

琼岛杨一年生播种苗生长节律研究

于2019年5月6日到12月25日对海南省琼岛杨Populus qiongdaoensis一年生播种苗的苗高、地径生长量进行定期观测,采用Logistic方程进行生长进程拟合,研究琼岛杨的苗期生长节律。结果表明,琼岛杨苗高和地径生长都呈现"慢—快—慢"的"S"形生长规律,且苗高、地径生长量与Logistic方程的回归相关性达到极显著水平,其相关系数分别达0.994和0.996。苗高生长速生期约119 d,占生长期的39.67%,占苗高年总生长量的63.77%;地径生长速生期约125 d,占生长期的45.42%,占地径年总生长量的66.15%。     

黄连木苗期年生长节律及其生物量分配规律

为给黄连木幼苗生产管理提供参考,在定期观测的基础上,研究黄连木苗期年生长动态、生物量积累与分配规律以及植物生长指标与生物量组分的相关性。结果表明:在整个苗期生长过程中,黄连木的苗高、地径、冠幅生长均呈现"S"型曲线,用Logistic生长方程和生长曲线能对其动态生长节律进行很好地拟合。结合实际测量值将黄连木1年生幼苗的生长过程分为4个阶段:出苗期、生长初期、速生期和生长末期。各指标速生期的生长量占其总生长量50%以上;黄连木1年生苗木的地上与地下部分生物量比例为1.78∶1.00;苗木生物量各指标中,地径与苗高、茎干质量、叶干质量显著相关,苗高与茎干质量、叶干质量显著相关,茎干质量与叶干质量极显著相关。     

有序样本聚类分析在长序榆苗高生长期划分中的应用

以长序榆苗高净生长量为样本 ,采用有序样本聚类分析将长序榆苗高生长过程划分为 4个时期 :出苗期为 4月 13日～ 5月 1日 ,生长初期为 5月 2日～ 8月 1日 ,生长盛期为 8月 2日～ 10月 2 1日 ,生长后期为 10月 2 2日～ 12月 1日。生长盛期时间较短 ,但生长量却占总生长量的 74 19% ,保证生长盛期有充足的水肥条件和延长生长盛期的时间是提高生长量的关键     

插穗长度与GGR6处理对乌柳扦插苗生长的影响

为了研究插穗长度和植物生长调节剂GGR6处理乌柳扦插苗生长的影响,本文通过设置,不同长度插穗,不同GGR6浓度处理,比较分析乌柳扦插苗的生根及苗期生长特点。结果表明:在一定范围内,插穗长度大于10cm,对高生长、分枝数和成活率均有显著的促进作用,小于10cm,成活率、高生长量显著降低;100ppmGGR6是适合乌柳扦插苗处理的最佳浓度。     

马尾松3代种质苗高生长参数的配合力分析

Combining ability of seedling height and shoot elongation parameters for the third generation germplasm of Pinus massoniana were investigated with a 6×6 half diallel cross design, and the parents were selected from the second generation breeding population. The result showed that the net increment of initiation phase, linear phase and later phase of seedling height took 22.82%, 59.05% and 18.13% of the total increment respectively, the increment at linear growth stage played a decisive role in the total increment of seedling height. The result of combining ability showed that, except for total linear growth (TLG), there were not significant differences in general combining ability (GCA) of seedling height, maximum growth rate (MGR), linear growth day (LGD) and linear growth rate (LGR), but for specific combining ability (SCA), except for LGD, there existed significant differences in seedling height, MGR, TLG and LGR, and the dominant gene effect was predominant over the additive gene effect. The reason for this seemed to be that the indirect selection of GCA had been made on mating parents. Compared to the second generation germplasm, which the mating parents had been indirect selected on GCA, the change was little for genetic control model of this trait in the third generation germplasm, and only the variance component of SCA increased to a certain extent.     

木荷地理种源苗期性状遗传变异研究

对采自6省(区)37个木荷种源种子进行了苗期试验,结果表明：木荷种源间苗高、地径、生物量有着极显著的差异,且有较高的广义遗传力。木荷苗高生长以8-9月份为速生期,这时期的生长占年生长的50％～56％,苗高和地径生长与纬度呈极显著负相关,说明通过木荷种源选择,能取得较好的效果,并初步筛选出广东开平、阳山、韶关,福建华安,江西上犹等苗期生长表现突出的种源。     

‘华仲11号’杜仲在植物生长调节剂处理下生长参数的分析

【目的】研究不同植物生长调节剂处理对‘华仲11号’杜仲苗期生长规律的影响情况,为杜仲树势调控和定向培育技术的研究提供理论依据。【方法】以‘华仲11号’杜仲1年生平茬苗为研究材料,在其叶面分别喷施浓度依次为200、400、600 mg·L^-1的三碘苯甲酸、缩节胺和多效唑,比较不同处理对‘华仲11号’杜仲苗高和地径生长的影响情况,并用Logistic模型拟合‘华仲11号’杜仲在不同处理下苗高和地径的生长曲线方程,分析各方程生长极值(k)、速生期始期(t_1)、速生期结束期(t_2)、速生期(t_2-t_1)及速生点(t_0)等参数的特点及其相互间的关联程度。【结果】不同处理下‘华仲11号’的苗高为104.73~159.14 cm,地径为12.31~16.31 mm,方差分析结果表明,不同处理间存在显著差异;浓度为400 mg·L^-1的多效唑处理对苗高和地径的抑制作用均最显著,该处理的苗高和地径与对照相比分别低34.19%和24.52%。各处理下‘华仲11号’杜仲苗高生长曲线方程的决定系数(R^2)为0.993~0.998,地径生长曲线方程的决定系数(R^2)为0.994~0.999。各处理下‘华仲11号’杜仲苗高的速生期始期(t_1H)与速生点(t_0H)、速生期结束期(t_2H)之间均有显著的正相关关系,其拟合方程的决定系数(R^2)分别为0.697和0.435;苗高生长极值(k_H)和苗高的速生期结束期(t_2H)、速生点(t_0H)之间也都有显著的正相关关系,其拟合方程的决定系数分别为0.534和0.447。【结论】浓度为400 mg·L^-1的多效唑处理对‘华仲11号’杜仲苗高和地径生长的抑制效果均最好;各处理均可通过Logistic方程拟合苗期生长规律;可采用苗高指标对植物生长调节剂的抑制效果进行评价。