Plus tree of Cryptomeria japonica D. Don with a heterozygous male-sterility gene

To find plus tree clones of Cryptomeria japonica that are heterozygous for a male-sterility gene (Aa), we crossed a homozygous male-sterile tree (aa) with 63 clones. Male sterility in this case is controlled by a recessive allele at a single gene locus and is expressed only in homozygotes. All F₁ seedlings obtained by crossing the male-sterile mother tree and 62 out of the 63 clones produced pollen. In contrast, F₁ seedlings obtained from the crossing between the male-sterile mother tree and a plus tree clone, Ohara 13, produced 64 male-sterile individuals and 52 fertile individuals. The segregation ratio fitted the expected 1 : 1 ratio according to a chi-square test. These results clearly demonstrate that the Ohara 13 clone is heterozygous for a male-sterility gene.     

水分胁迫对日本柳杉种子萌芽的影响

本文采用配置不同浓度的PEG(聚乙二醇)溶液来模拟土壤自然水势，对日本柳杉种子萌芽实验进行人工水分胁迫处理。结果表明：随着水势的下降，其发芽率在轻度水分胁迫下有所上升，然后降低，随PEG浓度上升到15％时，发芽率、发芽速度、发芽指数、活力指数、芽长等都出现不同程度的降低。而当PEG浓度上升到25％时，则上述指标均受到强烈抑制。结果表明，日本柳杉在轻度干旱胁迫时，具有一定的耐旱性。     

Study of sugi (Cryptomeria japonica D. Don) with male-sterility gene using CAPS markers

The frequency of open-pollinated male-sterile seedlings from a male-sterile mother tree in Cryptomeria japonica D. Don was determined in 765 open-pollinated seedlings. Pollen was not formed by 29 out of the 765 seedlings. To find pollen donor candidates for 29 male-sterile seedlings, a male-sterile tree was crossed with five individuals in the neighborhood of the mother tree. Analysis of microspores in male flowers of F₁ seedlings revealed that one of the five individuals had a heterozygous male-sterility gene. Paternity tests were conducted on the 29 male-sterile seedlings using eight kinds of CAPS markers in C. japonica. The pollen parents of 29 male-sterile seedlings were not only a tree in the neighborhood of the mother tree, but also other trees. Since it was found that the pollen parents of four of the male-sterile seedlings were not in the study plot, it was inferred that C. japonica trees that possess the male-sterility gene grow in other places and may be widely distributed.     

柳杉木材边材木醋液中的成分研究

用毛细管气相色谱法对日本柳杉木材边材炭化得到的木醋液中的37种成分进行定性和定量分析.结果表明,醇类、酮类、羧酸类、呋喃类、苯酚类及愈创苯酚类是其主要成分.用溶剂萃取-硅胶柱层析法进一步分离处理木醋液,纯化出炭化过程中产生的手性脱水内醚糖-左旋葡聚糖(LGA,1,6-脱水-β-D-葡萄糖),但其不能被毛细管气相色谱法检...     

Genetic variation in height growth curves observed in three clonal tests of sugi (Cryptomeria japonica D. Don) in Kyushu

Genetic variation in the height growth curves was investigated by analyzing data from three clonal trials of sugi (Crytomeria japonica D. Don) in Kyushu. Average height of twelve clones measured at each of five years until 30 years of age were fitted to the Chapman-Richards function with two parameters model. Clonal variation in the two parameters (an upper asymptote and a rate of growth parameter) was statistically significant across the tests, indicating that height growth pattern is under genetic control. The type of growth curve was clearly classified with the two parameters and agreed with the empirical classifications of the growth habit of local varieties. The rate of growth parameter was correlated with total height up to 20 years of age, while the upper asymptote was correlated only with the last ten years’ increment from 21 to 30 years where the clonal repeatability was decreasing. This indicates that a clonal selection for long rotation management system would not be reliable unless the height is measured accurately with more advanced devices or it is adjusted by the current increment of diameter.     

Estimating individual tree heights of sugi (Cryptomeria japonica D. Don) plantations in mountainous areas using small-footprint airborne LiDAR

Recently, it was shown that individual tree heights could be accurately estimated using small-footprint airborne light detection and ranging (LiDAR) remote sensing. Because most of the areas studied previously were limited to flat terrain, we investigated the accuracy of LiDAR-derived individual tree height estimates for different types of topographical features in mountainous forests with a steeper and more complex topography. Several middle-aged (40–50 years old) sugi (Cryptomeria japonica D. Don) plantations are found in the mountainous regions in Japan; hence, we chose 48-year-old sugi plantations to investigate the accuracy of these estimates. The surveyed area was divided into three types of topographical features; steep slope (mean slope ± SD; 37.6° ± 5.8°), gentle slope (15.6° ± 3.7°), and gentle yet rough terrain (16.8° ± 7.8°). Before estimating tree heights, the number of detected trees within each topographical feature was researched. In each of these terrains, the percentage of trees detected correctly was 74%, 86%, and 92%; the average error between LiDAR-derived and field-measured tree heights was 0.227m, –0.473m, and –0.183m; and the accuracy of the LiDAR-derived tree height estimates, given as root mean square error (RMSE), was 0.901m, 0.846m, and 0.576m, respectively. Consequently, the procedure presented in this study could detect most canopy trees and estimate individual tree heights with an accuracy better than 1m, even in a forest with a mean slope angle of approximately 38°; thus, indicating that small-footprint airborne LiDAR will be a useful tool for accurately estimating the heights of individual canopy trees in sugi plantations in mountainous areas.     

Cytological and genetical studies on male sterility inCryptomeria japonica D. Don

Genetic male sterility is a useful trait in plant breeding, especially in angiosperm crops such as corn, onion and carrot. We found a male sterile sugi (Cryptomeria japonica D. Don) tree in Toyama, Japan. Pollen of sugi is one of the major causes of pollinosis in Japan. We carried out this research in an attempt to make clear the characteristics and inheritance of this male sterility. Microsporogenesis of the male sterile tree proceeded meiosis, however, the microspores collapsed after they were separated from pollen tetrads in locules, resulting in complete male sterility. Most likely, ethylene evolution was responsible for male sterility expression. Full seed setting in the male sterile tree indicated normal macrosporogenesis. Seeds obtained from crossing between male sterile and normal lines showed relatively high level of germination and their seedlings grew vigorously. The somatic chromosome numbers of 241 germinated seeds, derived from the male sterile tree, were mostly 22, euploid. These results indicated that male sterile tree was different from other similar previously reported trees with low pollen fertility, resulting from triploid or trisomics. Probably, male sterility in sugi is either nuclear genetic male sterility or cytoplasmic male sterility. The study was partially supported by Program for Promotion of Basic Research Actives for Innovative Biosciences.     

Environmental effects on the color of sugi (Cryptomeria japonica D. Don) heartwood

Sugi (Cryptomeria japonica D. Don) is one of the most important planted trees in Taiwan. The normal heartwood of sugi has a red to pinkish rose color. Unfortunately, this pleasant appearance is susceptible to discoloration after environmental exposures. This discoloration is a serious defect that decreases the value of sugi products. The objective of this study was to investigate the effects of environmental factors such as moisture, oxygen, and lights of different wavelengths on the discoloration of sugi. The results show that under the combined effects of light and oxygen the color of heartwood changes from red (or rosepink) to bluish green. The color further darkens and eventually turns to black with the presence of moisture. As for the effect of light wavelengths on the discoloration of sugi heartwood, it was found that the red color was enhanced after being irradiated with light of wavelengths above 600 nm. Botha ^* andb ^* values increased significantly as a result of such exposure.     

醋酸水溶液预处理对柳杉木材炭化的影响

杉木(日本柳杉)经醋酸水溶液处理后，重量减少。将处理前后柳杉木材在4℃下进行炭化，得到了木醋液、木焦油和木炭。与未处理材相比，处理材木醋液的收率增加，而木焦油和木炭的收率减少。处理液的醋酸浓度增加后，木醋液和木焦油的收率几乎不变，但木炭的收率稍微减少了。用毛细管气相色谱法对木醋液的成分进行了定量分析。与未处理材相比，处理材木醋液中糠醛(呋喃甲醛)及5-羟甲基糠醛的收量增加，而羧酸类、苯酚类、邻苯二酚、愈创木酚类及麦芽酚的收量几乎不变。当醋酸浓度从0增至3％时，糠醛的收量随着增加，但是当醋酸浓度从3％增至30％时，其收量却几乎不变。     

The effect of alternating temperature on the rest break process of male flowers of Cryptomeria japonica D. Don

In order to develop a model for predicting the period of male flower anthesis in Cryptomeria japonica, it is requisite to clarify the rest break process in male flowers. In this study, the effect of alternating temperatures in a daily cycle on rest break was investigated using twigs bearing male flowers from three clones of C. japonica. Four temperature treatments with the same daily mean of 8°C were applied to sample twigs over a period of 35 days: (1) 8°C constant (TR-A); (2) 7°–10°C alternating (TR-B); (3) 5.5°–13°C alternating (TR-C); and (4) 4°–16°C alternating (TR-D). After treatment, the sample twigs were forced to bloom at a constant temperature of 16°C, and the cumulative effective temperatures (CETs) required for anthesis were compared. While the CETs for anthesis were the same for TR-A and TR-B, that for TR-C was significantly higher. After TR-D, almost no male flower bloomed, indicating that this treatment was ineffective in breaking rest. When considering these results on an hour basis, it was a reasonable interpretation that 13°C had no effect on breaking rest while the temperatures below 10°C were all equally effective. On the other hand, temperatures of 16°C or above were considered to have an antagonizing effect that cancels the effects of chilling temperatures below 10°C. These results suggest that the effects of high temperatures during the daytime in chilling periods should be properly incorporated into a model of the process by which rest of male flowers is broken.     

利用RAPD分析药用石斛的遗传多样性及亲缘关系

通过对9种药用石斛进行遗传多样性和亲缘关系的分析,为更好地开发利用石斛资源奠定基础。采用RAPD技术,应用NTSYS软件对9种石斛的RAPD-PCR结果进行分析。利用从103条随机引物中筛选出的70条随机引物对供试材料DNA进行随机扩增,共得到520条带,其中多态性带有491条,多态性百分率为94.42%。采用UPGMA类平均法对扩增出的谱带进行遗传聚类分析,得出反映各种间亲缘关系的树状图。在遗传距离（D）=0.44处,可将供试材料分为2类,RAPD对基因组的分析结果与传统分类学的结果差异不大。试验结果表明,RAPD技术可有效地应用于药用石斛的遗传多样性及亲缘关系的研究。     

西藏柏木抗旱生理研究

本研究采用人工干旱对比盆栽试验方法,探讨在水分胁迫下,西藏柏木生理生化指标变化规律及其抗旱机制。研究结果表明：在干旱条件下,叶水势降低,水分饱和亏缺增加,失水速率减小;电解质渗透率略有降低,脯氨酸累积增加,叶绿素ａ／ｂ值变大;生长阻滞含水量是田间持水量的５７％。综合分析表明,西藏柏木属于抗旱植物,抗旱机制是低水势忍耐脱水。     

Species richness in sugi (<Emphasis Type="Italic">Cryptomeria japonica</Emphasis> D. DON) plantations in southeastern Kyushu,Japan: the effects of stand type and age on understory trees and shrubs

 The species richness of trees, shrubs and climbing plants was investigated in 41 sugi (Cryptomeria japonica D. Don) plantations of different stand age and area in southern Kyushu, southwestern Japan. Altogether 174 species were found, of which 145 infrequent species were selected for analysis. Two groups were extracted from the species list according to their occurrence in older (49 spp.) or younger (28 spp.) stands, the latter containing a higher percentage of climbing plants and species with wind-dispersed seeds. In contrast, the older stand group contained major tree components typical of seminatural, evergreen broadleaved forests in the region and was more heavily dependent on stand age, especially for species with gravity- and frugivore-dispersed seeds, showing a gradual increase up to 60 years old. The species richness was less correlated with edge perimeter facing seminatural forests and the years after latest thinning. The juxtaposition of plantation compartments with stands of seminatural forest or other plantations, as well as the compartment's origin as former plantation site or a seminatural stand, had relatively little influence on species richness. However, topographic variation was important in determining the species composition, with valley stands having higher species richness and containing many plants typical of the regional seminatural forests. These results suggest that (1) the major trend of species richness is determined by the presence of old stand type species, (2) topographic variation of species richness remains even after establishment of plantations, and (3) the normal rotation period of sugi plantations (35–40 years) may therefore be too short to conserve the maximum potential species diversity within the working forest. Received: June 4, 2001 / Accepted: August 26, 2002 Acknowledgments We wish to thank the staff of the Miyazaki University Forests for cooperation in the fieldwork. A part of this study was supported by the Grant-in-Aid for Scientific Study from the Ministry of Education, Science and Culture of Japan (no. 09041071 and no. 10460068). Correspondence to:S. Ito     

The penetration rate of laser pulses transmitted from a small-footprint airborne LiDAR: a case study in closed canopy, middle-aged pure sugi (Cryptomeria japonica D. Don) and hinoki cypress (Chamaecyparis obtusa Sieb. et Zucc.) stands in Japan

Penetration rates of laser pulses transmitted from a small-footprint airborne light detection and ranging (LiDAR) system in closed-canopy, middle-aged (40–50 years old) hinoki cypress (Chamaecyparis obtusa Sieb. et Zucc.) and sugi (Cryptomeria japonica D. Don) plantations that had similar levels of canopy openness were studied. The number of transmitted pulses was 107 427 points/ha for the hinoki cypress stand and 122 883 points/ha for the sugi stand. The penetration rates of the first (P_f) and second pulses (P_s) that reached the ground were 0.1% and 1.0% in the hinoki cypress stand, and 2.6% and 5.5% in the sugi stand, respectively. Penetration rates for the total number of pulses (P_f+s) that reached the ground within each stand were 1.1% and 8.1%, respectively, and values for P_f+s, P_f, and P_s for sugi and hinoki cypress stands were significantly different (P < 0.001). The results of this study indicated that the generation of accurate digital terrain models in dense hinoki cypress stands with complex topographies using only the data from laser pulses with poor laser penetration rates is likely to be difficult.     

Effects of the absorption of artificial acidic solutions on the root systems of Japanese red cedar (Cryptomeria japonica D. Don) cutting and saplings

The effects of the absorption of artificial acidic solutions only from below-ground parts on root systems were examined for 60 days in summer and 72 days in fall using cuttings and saplings of Japanese red cedar (Cryptomeria japonica D. Don). Cuttings and saplings absorbed the solutions through the potted soils from the reservoir of an autoirrigator and/or a simplified-autoirrigator. Nitric acid solutions of pH 2.0, 4.0 and 6.0 and distilled water (control) were used in summer, mixtures of H₂SO₄ and HNO₃ solutions of pH 2.0, 3.0 and 4.0, HNO₃ solution of pH 3.0, H₂SO₄ solution of pH 3.0 and distilled water (control) were used in fall. Although no detrimental effects of acidic solutions on saplings were observed, the rooting rate of cuttings treated at pH 2.0 in summer was significantly lower than that of the control. Root lengths and root dry weight per cutting at pH 2.0 in summer and fall were smaller than those of the control, and the difference in fall was significant. The present study revealed that the acidic treatment only from below-ground parts had detrimental effects on the root systems of cuttings, suggesting the importance of quantification of the effects on below-ground parts, as well as on above-ground parts, to evaluate the effects of acidic precipitation on trees.     

毛红椿天然群体遗传多样性及取样策略探讨

[目的]研究毛红椿天然群体遗传多样性取样策略,为其种质资源收集、保存和遗传多样性保护等提供参考依据。[方法]利用8对微卫星分子标记进行毛红椿天然群体遗传多样性和空间自相关分析,综合制定其天然群体合理取样策略。[结果]毛红椿天然群体等位基因数平均为7.5个,期望杂合度(H_e)和多态性信息指数(PIC)均值分别为0.643 7和0.636 0,基因分化系数(G_(ST))均值为0.290 7。在遗传多样性取样策略方面,提出了根据毛红椿群体基因分化系数来确定取样群体遗传变异所占总变异比例的运算公式为1-(G_(ST))~(n-1),其中,n为取样群体的数量。当取样群体达到4个时,基本上能包括该树种97.5%的遗传变异;同时确定了目标群体的选择方法,应选择与其它群体间基因分化系数均值较大的4个群体,即贵州册亨(CH)、浙江遂昌(SC)、浙江仙居(XJ)和云南师宗(SZ)。通过构建云南宾川(BC)、云南师宗(SZ)和江西宜丰(YF)群体内取样单株数量与基因多样性和等位基因之间的捕获曲线,确定了群体内取样单株数量应达到15个以上;毛红椿天然群体内300～520 m范围内的单株间存在相似关系,超出此范围个体间差别较大,说明在进行群体内单株取样时,单株间距应大于520 m。[结论]取样群体数量、群体间遗传分化系数、群体内单株数量以及单株间距离等影响了毛红椿取样群体的遗传多样性。毛红椿天然群体遗传多样性取样策略为取样群体4个、每个群体最少取样15个单株,单株间距大于520 m。     

四照花和狭叶四照花种子的萌发试验

对四照花和狭叶四照花种子进行不同处理的萌发试验。结果表明四照花种子的发芽率显著高于狭叶四照花种子；干藏1年的狭叶四照花种子的生活力已完全丧失。经用0．05％赤霉素预处理后沙播的四照花种子，其发芽率极显著高于未使用赤霉素处理的沙播和土播的种子，且种子出苗整齐，发芽快，发芽时间比其提前4～7天；用0．05％赤霉素处理后沙播的种子和未用赤霉素处理直接土播的种子，其发芽率显著高于未经赤霉素处理而沙播的种子。狭叶四照花仅土播种子与沙播种子间存在差异。试验结果还表明四照花和狭叶四照花种子的萌发需要经过一个低温阶段。     

Mitigation of aluminum toxicity by calcium and magnesium in Japanese cedar (Cryptomeria japonica)

We investigated the short-term and long-term mitigation of Al toxicity by Ca and Mg in pot trials of Japanese cedar (Cryptomeria japonica D. Don). We found that in the initial stages of treatment, Al toxicity at high Al concentration (5mM) was mitigated by Ca and Mg through the stimulation of antioxidant enzyme activities in needles. However, growth reduction occurred after 11 months exposure to Al despite the coexistence of Ca and Mg. Growth reduction was related to Al³⁺ activity in solution rather than the concentration of Ca and Mg. Therefore, when considering the influence of soil acidification on Al toxicity in forest ecosystems, it is important to consider not only the potential for mitigation of Al toxicity by base cations, but also the potential for factors in the soil solution to change the chemical form of Al.     

柳杉平均高与平均胸径模型的研究

本文采用二元回归方程建立柳杉平均高和平均胸径的模型，其复相关系数分别达０．９８和０．９５，经检验达极显著水平，同时应用Ｆｒｅｅｓｅ法ｘ２检验和误差估计表明上述２个模型均为较理想模型。     

日本花叶矢竹组织培养与叶色变异研究

花叶矢竹是矢竹的一个栽培变种.该文以花叶矢竹的侧芽生长点为外植体,研究了单独添加不同质量浓度的6-苄基腺嘌呤(N-6-Benzyladenine,6-BA)、噻二唑苯基脲(Thidiazuron,TDZ)和玉米素(zeatin,ZT),BA与ZT相互组合,MS培养基与添加激素的培养基交替培养对花叶矢竹试管苗增殖生长及叶色变异的情况,结果表明:单独添加BA时促进试管苗侧芽增殖,新芽乳白色,叶片绿色条纹,而添加ZT的试管苗伸长生长良好;当BA与ZT相互作用时,以3 mg·L-1BA和3 mg·L-1ZT组合时芽增殖系数较大,且新苗生长良好;交替培养有利于新芽生长,且保持花叶特性.