毛竹笋套袋技术研究

采用样地调查法对刚出土或冒出土层(笋尖高出地面小于5 cm)的粗壮毛竹笋分别用3种套袋方式进行套袋,包括带支架单袋、带支架双袋、无支架单袋,并选取部分未套袋的竹笋进行对照。对所有套袋与未套袋的竹笋每隔2 h进行地径、高度以及袋内外的温度、湿度现场测定。并挖取样笋进行生物量、可食率以及营养成分测定。结果表明:套袋能够提高毛竹笋生长的温度、湿度,能促进毛竹笋的高、地径生长,能显著提高竹笋的可食率和竹笋品质,从而提高竹林效益。     

毛竹林覆盖技术研究

研究了双层覆盖、单层覆盖对毛竹林出笋时间、笋期、竹笋产量、竹林土壤温湿度、幼竹及幼鞭生长状况等的影响。结果表明:覆盖措施显著提高竹林土壤温度,但对土壤含水率影响不显著;双层覆盖竹林出笋时间较单层覆盖和对照竹林分别提前6 d和15 d,笋期较单层覆盖和对照竹林分别增加9 d和15 d;双层覆盖竹林相对于对照竹林在竹笋净产量和竹笋可食部分重量方面分别增加95%和102%;双层覆盖竹林幼鞭平均深度明显低于对照竹林,跳鞭数量明显高于对照竹林,表明覆盖措施对竹鞭生长具有不利影响。     

Relationships of culm surface area to other culm dimensions for bamboo, Phyllostachys pubescens

We determine the relationships of culm surface area to other culm dimensions for one of the largest bamboo species, Phyllostachys pubescens Mazel ex Houzeau de Lehaie. A total number of 150 sample culms were collected from a stand of P. pubescens in Mt. Toshima, Kumamoto Prefecture, western Japan. The culm surface area for each sample was calculated, and then the relationships of the culm surface area to basal area and product of diameter at breast height (dbh) and culm height were analyzed. The relationship between culm surface area and basal area could be described successfully by the power equation, whereas there was a linear relationship of culm surface area to product of dbh and height. Although the regression equations determined here would be useful in estimating culm surface area of P. pubescens, it is necessary to select an appropriate equation depending on the purpose and available time and labor.     

毛竹笋用林高产高效培育技术

传统技术经营下的毛竹林一般仅主产冬、春二季笋，而要促成高产高效必须进行管理上的技术革新才能实现，新技术的运用增添了夏、秋两季笋（鞭笋），既显著地提高了经营者的经济效益，又能使人们在暑热的夏季和干燥的秋季也能吃到鲜笋，丰富了蔬菜品种。     

Thermo characteristics of steam-exploded bamboo (Phyllostachys pubescens) lignin

Bamboo (Phyllostachys pubescens) internode was subjected to steam explosion treatment to produce an excellent fiber for binderless boards. Lignin was isolated from extract-free bamboo meal with Björkman’s procedure and steam-exploded pulp. The self binding-mechanism was discussed by scanning electron microscopy (SEM), thermo-gravimetry (TG), differential scanning calorimetry (DSC) and analytical ozonation. It is well-known that steam explosion treatment liberates lignin from the cell wall to the fiber surface, which is the most important component relevant to binderless board production. Results of TG and DSC analyses showed that steam-exploded bamboo pulp started mass loss at lower temperature compared to bamboo internode meal. The thermal softening temperature of lignin prepared from steam-exploded pulp was much lower than that of lignin prepared from extract-free bamboo meal. This suggests that intermonomer linkages of lignin, especially β-aryl-ether linkage which is the major intermonomer linkage of lignin, were cleaved during steam explosion treatment resulting in low molecular weight phenolic compounds. The cleavage of β-aryl-ether intermonomer linkage of lignin was also confirmed by ozonation analysis.     

毛竹竹腔富硒施肥对竹笋品质的影响

采用不同配比液态富硒肥对毛竹进行竹腔施肥试验。结果表明:富硒肥中大量元素可明显改善竹笋氨基酸含量,微量元素对改善竹笋品质效果不明显,但增加微量元素可促进竹笋对硒元素的吸收;富硒肥中亚硒酸钠浓度对提高竹笋硒含量影响显著;采用大量元素(A)3、微量元素(B)3、亚硒酸钠(C)3配比的富硒肥对提高竹笋硒含量、改善竹笋品质的效果最佳。     

Rainfall interception in a moso bamboo (Phyllostachys pubescens) forest

In recent years, moso bamboo (Phyllostachys pubescens) forest areas in Japan have rapidly expanded, and bamboo is now invading nearby natural or plantation forests. To date, only one study has examined the rainfall interception of a moso bamboo forest. In that study, it was reported that the interception ratio (interception/rainfall) of the bamboo forest did not exceed the interception ratios of other natural and plantation forests (n = 4) in Japan. To expand the current state of knowledge about rainfall interception of bamboo forests, we measured throughfall and stemflow at another bamboo forest site. Annual rainfall (Rf), throughfall (Tf), and stemflow (Sf) during the measurement period were 2,105, 1,556, and 322 mm, respectively. Annual rainfall interception at the plot (I) was 228 mm. Tf/Rf, Sf/Rf, and I/Rf were 73.9, 15.3, 10.8%, respectively. I/Rf was less than 20% throughout the year except in October, the month with lowest rainfall. We also summarized rainfall interception data from 19 other natural and plantation forests. The I/Rf value of our site did not exceed the I/Rf values of these natural and plantation forests (n = 19). Our data will be useful for assessing changes in water resources that result from replacement of natural or plantation forests by bamboo forests.     

Antibacterial compounds from shoot skins of moso bamboo (Phyllostachys pubescens)

Bamboo is intricately associated with human activity, and its usefulness is well known. For example, its roots and leaves have been used as medicinal products. Also, studies on the medicinal properties of bamboo leaves have shown antioxidant, anticancer, and antibiotic properties. In this study, we determined that the dichloromethane soluble of the methanol extract from the bamboo shoot skin (Phyllostachys pubescens) inhibited the growth of Staphylococcus aureus. The active constituents were isolated and identified as stigmasterol and dihydrobrassicasterol by NMR and mass spectrometry. These compounds inhibited the growth of S. aureus and Escherichia coli. Also, from the standpoint of structure–activity relationships, the activities of these phytosterols depend on their side chain structures. These findings indicate that the extracts of bamboo shoot skins as well as its active compounds in the skins are potentially useful as antibacterial materials.     

毛竹笋材两用林定向培育技术

建设高效林业,提高竹林经济效益,增加林农收入,就必须科学地经营管理竹林。株洲县通过对3 600 hm2的毛竹林实施笋材两用林定向培育,实施后,给全县林业和竹农带来了可观的经济效益。     

Mode I interlaminar fracture property of moso bamboo (Phyllostachys pubescens)

Bamboo is a unidirectional fiber-reinforced bio-composite. Once having cracks, the delaminating propagation is not controlled by the strength but by the interlaminar fracture toughness. In this paper, the behaviors of Mode I (crack opening mode) interlaminar fracture parallel to grain of moso bamboo (Phyllostachys pubescens) were studied. Based on energy theory, the Mode I interlaminar fracture toughness, G _IC, was measured using the double cantilever beam specimens, and the fracture surfaces were examined under scanning electron microscope. The results show that: (1) the interlaminar fracture toughness of Mode I is the basic characteristic of bamboo material. The mean value of G _IC = 358 J/m² (coefficient of variation = 16.88%) represents the resistance arresting crack propagation. No significant difference was found for G _IC among the specimens located at different heights of the bamboo. (2) Due to the low G _IC of bamboo, the crack propagation parallel to grain developed easily. The crack was a self-similar fracture without fiber-bridging. On the fracture surfaces, smooth fibers and plane ground tissue were found at the extended area of Mode I fracture along the longitudinal direction. Under scanning electron microscope, it could be seen that the crack propagation developed along the longitudinal interface between fibers or ground tissue. It indicates that the longitudinal interface strength was weak among bamboo cells.     

毛竹一新变型——斑毛竹

描述了毛竹(Phyllostachys heterocycla cv.pubescens)的1个新变型——斑毛竹(Ph.heterocyc口la cv.pubescens f.porphyrosticta).它不同于原变型和安吉紫毛竹(Ph.edulisf.purpureoculmis)在于其新秆刚解箨时绿色,无斑点,从当年秋季开始节间逐渐出现紫色斑点,以后不断加密并可连接成紫色或淡褐色斑块,但并不占据整个节间.     

毛竹笋期切秆育苗与造林技术研究

通过对毛竹笋期切秆育苗与造林技术的7 a研究.结论是;(1)采用笋期切秆培育的毛竹苗具有竹秆分枝高度降低,竹节密度增加、枝条生长旺盛的特点.竹苗矮化、健壮,尤以笋期抽枝展叶前切秆培育的竹苗,其造林成活率为95.91%,第1年发笋株率为79.1%,发笋株单株发笋数为1.66个,分别比普通毛竹苗增加了21.31%、27.26%、53.7%,造林效果明显优于未切秆培育的普通毛竹苗.(2)切秆时期和切秆高度不同,对毛竹苗质量有明显影响.其中,笋期展叶前切秆、切秆高度在1.0～1.3 m的苗木造林效果最佳.(3)笋期切秆育苗是毛竹苗培育的一项技术创新,能大幅度提高造林成活率、发笋率,加快成林,提早受益,生态效益、社会效益、经济效益明显.     

Changes in chemical characteristics of bamboo (Phyllostachys pubescens) components during steam explosion

Chemical changes in cell wall components of bamboo internode during steam explosion process were analyzed to investigate self-binding mechanism of binderless board from steam-exploded pulp. More than 30% of xylose on initial mass, which is a major hydrolyzate of bamboo hemicelluloses, was lost after steam explosion treatment. Bamboo lignin is characterized by the presence of ester- and/or ether-linked p-coumaric acid to lignin. The content of phenolic hydroxyl groups of lignin isolated from steam-exploded pulp was characterized 2.3 times higher than those of the extract-free bamboo internode due to the cleavage of β-O-4 linkages. Alkaline nitrobenzene oxidation of the bamboo lignin gave vanillin, syringaldehyde and p-hydroxybenzaldehyde as major products. The content of p-hydroxybenzaldehyde decreased after steam explosion treatment, indicating the cleavage of ester- and/or ether-linked p-coumaric acid. The total yield of erythronic and threonic acids in ozonation products of the extract-free bamboo internode lignin was 268 mmol (200 g lignin)⁻¹, while those of lignins in the steam-exploded pulp and powdery fraction were 96 and 129 mmol (200 g lignin)⁻¹, respectively, suggesting the significant cleavage of β-O-4 linkages during steam explosion treatment. The cleavage of β-O-4 linkages was also confirmed by ¹H- and ¹³C-NMR spectroscopic observations.     

毛竹主秆人工造型研究

在毛竹竹笋长成新竹的过程中,利用正方型的铁制模具套住笋体,强制毛竹主秆形状由圆形变方形。试验结果表明：竹笋高度超出模具5cm以上、竹笋粗度周长等于或略小于模具周长的竹笋,套上模具后竹笋既可成活,毛竹主秆又可形成方型;竹笋粗度周长大于模具周长的,上模后须适时对模具放松竹笋才能成活成型;套模后成活成型的新竹胸围、枝下高、全竹高只有对照的80％、53．8％、56．4％。研究表明在毛竹竹笋长成新竹的过程中,其主秆形状有可塑性,但对新竹的胸围、枝下高、全竹高生长有严重影响,会导致毛竹主秆矮化。     

Rapid extraction of epidermis chlorophyll of moso bamboo (Phyllostachys pubescens) culm using ultrasonics

The feasibility of applying ultrasonics to the chlorophyll extraction of bamboo culm was evaluated to establish an efficient reliable method for chlorophyll extraction from the epidermis of bamboo culm. The results demonstrate that extraction of epidermis chlorophyll from bamboo culm with acetone by ultrasonics for 3 min is a rapid, reliable method.     

风电叶片用毛竹和麻竹竹青片层积材性能评价

利用动态热机械分析仪（DMA）检测3～4年竹龄的毛竹与麻竹竹青试件的常温存储模量值,再按竹龄分别将毛竹与麻竹竹青制成竹青层积材,利用INSTRON5582万能力学试验机对毛竹与麻竹竹青层积材分别进行检测。实验证明：随着毛竹与麻竹竹龄的增加,毛竹与麻竹竹青试件的常温存储模量值也相应的增加。也就是说,在常温条件下毛竹与麻竹竹青的刚性随竹龄的增加而增加。3年生以上的成熟麻竹竹青部分的常温存储模量位于10 GPa数量级以上,一般能满足作为风力发电叶片复合材料中增强相材料的使用。而4年生以下毛竹的存储模量值有可能低于10 GPa,达不到风力发电机叶片复合材料对毛竹增强相的最低要求,一般不作为风力发电机叶片复合材料毛竹增强相使用。     

The suitable harvesting season and the part of moso bamboo (Phyllostachys pubescens) for producing binderless boards

The properties of the binderless boards of moso bamboo depending on the harvest seasons and the parts of the height were reported and the optimum harvesting conditions investigated. The binderless boards were prepared from the powdered bamboo harvested each month from June to May, and the parts in height. The hot water extract (HWE), lignin, α-cellulose, and hemicelluloses contents were examined. The board properties were evaluated with internal bonding (IB), water absorption (WA), and thickness swelling (TS). From the experiment, the boards prepared between March and October had higher HWE content and higher IB and lower WA and TS than the ones prepared in other months. The board from the top part showed lower IB and higher WA and TS than the bottom and the middle. The boards prepared from the residue after extraction of HWE showed lower IB than the unextracted samples. These results indicated that for producing board from bamboo, the suitable harvesting season is when HWE contents are higher and that the suitable parts in height for harvesting are the bottom and the middle where lignin contents are not low.     

富硒施肥对毛竹笋硒含量及品质的影响

采用"丰硒源"富硒肥进行富硒施肥试验,研究不同施肥时间、不同施肥次数、施用不同硒含量富硒肥的施肥效果。结果表明:施肥时间、富硒肥的硒含量对竹笋硒含量的影响显著。施肥时间不仅影响竹笋的含硒量,还对竹笋的单宁含量影响显著。施肥时间对竹笋品质影响不明显;富硒肥中硒含量可显著影响竹笋品质,表现为随富硒肥硒含量的升高,竹笋品质逐步提高。     

毛竹立竹秆部电容初步研究

对毛竹立竹秆部电容进行了测定,结果表明：毛竹竹龄和电容测距对毛竹立竹秆部电容有较大影响,分别达到极显著和显著水平,毛竹立竹秆部电容呈现出随竹龄、测距的增加而降低、随胸径的增加而增加的趋势,可反映毛竹当时的生长状况。