Interactions Between Shoot Age Structure, Nutrient Availability and Physiological Integration in the Giant Bamboo Phyllostachys pubescens

Abstract: The age structure of adult shoots, the nutrient availability of the habitat, and their interaction, are important factors influencing the productivity of bamboo groves. In a field fertilization experiment over two years we examined the impact of physiological integration on the emergence, growth, and survival of new shoots of Phyllostachys pubescens, a giant woody bamboo. Impacts of physiological integration were compared using uniform and patchy fertilization treatments. The number of new shoots emerging per plot significantly increased with the application of fertilizer (NPK), but the increase was constrained by the age structure of adult shoots. In a year with a high proportion of shoots with new (first-year) leaves many more new shoots emerged than in a year with a low proportion of new leaves. Mean survivorship of the new shoots was constant at 20 % for all treatments in both years of study. Surprisingly, fertilization did not increase DBH or height of the new shoots, suggesting that shoot size was fixed early in ontogeny. The pattern of fertilizer application, either uniform or patchy, did not affect the total number of new shoots produced. In the case of patchy application, more new shoots developed in unfertilized patches in comparison to uniformly unfertilized plots, probably because these parts of the clone received resources via the rhizomes from the adult shoots in adjacent fertilized patches. The production of new shoots in fertilized patches, in turn, was lower than that in uniformly fertilized plots as a result of this physiological integration. The results are discussed in the general context of the impact of integration on clonal plant performance in dense stands.     

Radiocesium Distribution in Bamboo Shoots after the Fukushima Nuclear Accident

The distribution of radiocesium was examined in bamboo shoots, Phyllostachys pubescens, collected from 10 sites located some 41 to 1140 km from the Fukushima Daiichi nuclear power plant, Japan, in the Spring of 2012, 1 year after the Fukushima nuclear accident. Maximum activity concentrations for radiocesium ¹³⁴Cs and ¹³⁷Cs in the edible bamboo shoot parts, 41 km away from the Fukushima Daiichi plant, were in excess of 15.3 and 21.8 kBq/kg (dry weight basis; 1.34 and 1.92 kBq/kg, fresh weight), respectively. In the radiocesium-contaminated samples, the radiocesium activities were higher in the inner tip parts, including the upper edible parts and the apical culm sheath, than in the hardened culm sheath and underground basal parts. The radiocesium/potassium ratios also tended to be higher in the inner tip parts. The radiocesium activities increased with bamboo shoot length in another bamboo species, Phyllostachys bambusoides, suggesting that radiocesium accumulated in the inner tip parts during growth of the shoots.     

Progressive effects of shading on experimental wetland communities over three years

To investigate how the composition of wetland communities changes over time in response to altered light regimes, experimental communities of five Carex and four grass species were subjected to artificial shading (continuous or seasonal) in a three-year field experiment. Shoot number and size was measured after six weeks, and shoot biomass was harvested five times during the experiment. Communities were initially dominated by three grass species in all treatments, but subsequently, the Carex species increased and reached dominance in the control plots, whereas grasses remained dominant in the shaded plots. Shading had no effect on the biomass of communities or of single species in the first year. In the second year, community biomass was still unaffected, but shading reduced the biomass of three Carex species and also reduced species diversity. In the third year, shading reduced community biomass and all Carex species, but not species diversity. The greater shade tolerance of the grasses could not be explained by differences in morphological plasticity: after six weeks of growth all species had increased shoot height in response to shade by 40–70%. Grasses were hardly more plastic than Carex species. We propose that the long-term success of the Carex species in full light was due to a high allocation of biomass to belowground parts, which may have reduced losses caused by repeated harvesting of shoots (a simulation of management in productive wet meadows). Shading probably caused the Carex plants to change their allocation pattern, and thus prevented their progressive increase.     

灌溉对毛竹冬笋品质的影响

选取同一地形、长势一致的毛竹林为材料,分析比较灌溉与不灌溉毛竹林冬笋外观品质(个体重量、最大直径、长度、可食率)、营养品质(淀粉、蛋白质、脂肪、可溶性糖、维生素C)、呈味物质(单宁、草酸)、纤维素类物质(纤维素、木质素)以及不同类氨基酸含量的差异,研究灌溉对毛竹冬笋品质的影响,为冬笋的科学培育提供依据。结果表明：(1)灌溉显著提高了毛竹冬笋的个体重量、最大直径、长度以及可食率(P<0.05)。(2)灌溉显著提高了毛竹冬笋的淀粉和维生素C含量,并显著降低了单宁、草酸、纤维素以及木质素含量(P<0.05),但对蛋白质、脂肪、可溶性糖等指标含量影响不显著。(3)灌溉显著提升了毛竹冬笋中必需氨基酸、半必需氨基酸、鲜味氨基酸的含量以及占比(P<0.05),但对甜味和苦味氨基酸总含量影响不显著。研究发现,灌溉改善了毛竹冬笋生长和外观品质,以及呈味物质、纤维素类物质、必需氨基酸、半必需氨基酸和鲜味氨基酸含量等营养品质指标,从而显著提升了冬笋品质。     

Row orientation effects on FR/R light ratio, growth and development of field-grown bush bean

Bush bean ( Phaseolus vulgaris L. cv. Tenderette) plants were grown in north-south (N-S) and east-west (E-W) rows under field conditions to test effects of row orientation on reflected far-red (FR) light patterns and on shoot size and edible bean productivity. Soil water and nutrients were adequate. Plants in N-S rows received slightly higher ratios of FR relative to red (R) light, because of heliotropic movement of the leaves. Plants in N-S rows partitioned more dry matter to shoots and edible green beans than those in E-W rows. We conclude that row orientation of broadleaf plants can affect the FR/R light ratio and the phytochrome-mediated regulation of plant development under field conditions.     

Continuous harvesting of a dominant bracken alters a cool-temperate montane grassland community and increases plant diversity in Nagano,Japan

Declines in biodiversity can be caused by intense land-use or by land abandonment. Traditional plant-gathering in Japan has declined or has often been abandoned in recent decades. However, little is known about how traditional plant-gathering affects the diversity, productivity, and composition of plant communities. Traditionally, bracken (Pteridium aquilinum subsp. japonicum) served as a natural resource in Japan, and people continue to harvest it in some places. We conducted a 4-year field experiment in a cool-temperate grassland on the Sugadaira Plateau, Nagano Prefecture, comparing a continuous harvesting treatment of the dominant Pteridium with a non-harvested control. We wanted to determine whether Pteridium harvesting would alter plant species richness, total productivity, and plant community composition. Local people harvested Pteridium shoots in a 1800 m² treatment area each year from 2011 to 2014. By 2014, species richness and diversity (Shannon index) had significantly increased while Pteridium abundance (number of shoots and biomass) had decreased in the harvest treatment when compared with the control. Total productivity, measured as combined aboveground biomass of all vascular plant species, was similar between the treatment and control; however, community composition differed. Harvested plots had a higher biomass of erect-formed, invasive and native species, but lower biomass of small-formed species when compared with the control. Our results suggest that traditional plant-gathering, such as periodic Pteridium harvesting can result in increases in plant diversity while total productivity is maintained. However, long-term monitoring is recommended to detect any subsequent undesirable changes in the community, such as increases in invasive species populations.     

Physiological acclimation and growth response to partial shading in <Emphasis Type="Italic">Salix matsudana</Emphasis> in the Mu Us Sandland in China

In a controlled experiment, Salix matsudana plants were subjected to uniform nonshading (F-S), partial shading (P-S) and uniform shading (U-S). The shoots of the plants in the F-S and U-S treatments were referred to as H-H and L-L, respectively. The plants in the P-S treatment had two kinds of shoots: (1) shoots under the nonshading treatment that were connected to others under the shading treatment (H-L).(2) Shoots under the shading treatment that were connected to others under the nonshading treatment (L-H). The physiological acclimation and growth response of the species to the partial shading were examined. The partial shading had significant effects on photosynthetic dynamics, transpiration and stomatal conductance, but no effect on instantaneous water use efficiency and maximum quantum yield. Water saturation deficit and coefficient of water loss were significantly smaller in the H-L shoots than in the H-H shoots. Leaf natality, leaf mortality and leaf turnover were greater in the H-L shoots than in the H-H shoots. In contrast, these three parameters were smaller in the L-H shoots than in the L-L shoots. The H-L shoots had significantly larger branching ratio, total branch length and shoot biomass than the H-H shoots. The L-H shoots had smaller branching ratio, total branch length and shoot biomass than the L-L shoots. Total plant biomass in the treatments increased as follows: F-S相似文献   

中国亚热高大竹类植物毛竹竹笋克隆生长的密度调节（英文）

 对许多多年生克隆植物来说,大量的研究表明：当光是限制因子时,随着立地密度的不断增加,克隆分株的出生率逐渐减小、死亡率逐渐增加。本文观测了乔木状高大竹类植物毛竹竹笋的出生与存活过程,结果表明：竹笋的出生率,即每样方的出笋数,明显地随着成竹立竹度的增加而增加。更确切地说,竹笋的数量,不管是出笋数还是活笋数,都明显地随着带新叶(1龄叶)的成竹立竹度的增加而增加,而与带老叶(2龄叶)的成竹立竹度相关性不显著。并且竹笋的死亡率是非密度制约的。这可能是由于对毛竹来说,其立地总是比较开敞,而且,其竹笋的生长在很大程度上是不直接需光的。     

Dietary use of wild plant resources in the Sikkim Himalaya, India

The edible wild plants are greatly valued throughout the Himalayan region and serve as an important source of food for indigenous communities. This paper describes the botanical richness, elevational distribution and dietary use of the edible wild plant resources from the Sikkim Himalaya (Eastern Himalaya), many with promising potential. A total of 190 wild plant species have been screened from the Sikkim Himalaya, this derived from 143 genera and 78 families and accounting for nearly 15% of total edible wild plants resources of India. Of the total, 65% were edible for their fruits, 22% for leaves/shoots, 7% for flowers and 3% for roots/ rhizomes. Nearly 91 wild edible species were recorded from low-hills, 70 from mid-hills and 28 species from high-hill areas. Within Sikkim state, the North and East districts represent maximum diversity of edible wild plants due to the wilderness and inaccessibility to most of the habitats. An average rural family annually consumes nearly 8 types of edible wild plants, and a few species provide over five meals in a season. Selected plants also form a source of earning to a few families that sell them in local markets. It is suggested that the high diversity of edible plants needs to be conserved for future use. Some species may be grown in traditional agroforestry systems and on marginal lands of otherwise low agricultural value. Such measures may help protect wild plant resources in their natural habitats.     

Wild edible plants of the Sikkim Himalaya: Nutritive values of selected species

The wild edible plants form an important constituent of traditional diets in the Himalaya. In the Sikkim Himalaya a total of 190 species have been screened as edible species out of which nearly 47 species come to the market. The present paper deals with nutritive values of 27 most commonly consumed wild edible plants in the Sikkim Himalaya. Of 27 plant species that were analyzed for their nutritive values, 22 were edible for their fruits and five for leaves/shoots. Among different plant parts, generally higher nutrient concentration was recorded for leaves, followed by new shoots and fruits. For different species the crude fiber content ranged between 2.15–39.90%, and the total soluble salts between 4.66–21.0%, and the vitamin C content from 6-286 mg/100 g. The fat content was determined high in the fruits of Castanopsis species, Machilus edulis, and Cinnamomum species, while the protein content was highest in Hippophae rhamnoides, Cuc-umis melo, and Eleagnus latifolia. The total carbohydrate content ranged from 32-88% in the fruits of various wild edibles, the reducing sugar from 1.25–12.42%, total sugar from 2.10–25.09%, the lignin content varied from 9.05–39.51%, the hemicellulose between 25.63-55.71% and cellulose content varied from 9.57–33.19% in different species. Among the various mac-ronutrients estimated in the plant samples of different wild edible species, nitrogen was present in highest quantity, followed by potassium, calcium, magnesium, phosphorus, and sodium. Mi-cronutrients, such as iron, zinc, magnesium, and copper contents were analyzed in different plant parts of various wild edible species. The iron content was higher in leaves and new shoots. The study shows that wild edible plants are good source of nutrient for rural population, and also well comparable with various commercial fruits. It is suggested that a few wild edible species need to be grown for commercial cultivation and adopted in the traditional agroforestry systems, which will lead to reduced pressure on them in natural forest stands as well as producing economic benefits for poor farmers.     

桂西壮族饮食文化中野生食用植物的民族植物学研究

运用民族植物学方法,以广西西部的1市1区10县为研究区域,对桂西壮族饮食文化中利用野生食用植物的传统知识进行了调查和研究.结果显示:桂西壮族饮食文化中常用的野生食用植物有46科102种,其中菊科(Asteraceae)种类最多(13种),其次为苋科(Amaranthaceae)、伞形科(Umbelliferae)、蔷薇科(Rosaceae)和豆科(Leguminosae)(各6种).食用部位常为嫩枝叶、果实、全株、花、根和茎等,其中,食用部位为嫩枝叶的种类最多(48种),食用部位为根和茎的种类最少(8种),食用部位为果实、全株和花的种类分别有18、17和11种.食用方法有炒、煮汤、生食、凉拌、水煮、茶饮、上汤和配菜等,常见的食用方法为炒和煮汤.采摘时间主要为春季和夏季,部分种类可全年采食.不同区域的壮族民众对野生食用植物的选择具有随机性,主要依据方便、易得、适用、无污染等标准进行选择,且生活在不同区域、不同环境的壮族民众对野生食用植物的选择具有较明显差异.综合分析结果表明:桂西壮族民众拥有丰富的利用野生食用植物的传统知识,具有食用植物种类丰富、食用部位多样、食用方法多样等特点,形成了富有民族特色的饮食文化.此外,根据研究结果,对桂西壮族特色饮食文化的保护和传承进行了探讨,并对当地野生食用植物资源的可持续利用提出了一些建议.     

Impact of the arundo wasp,Tetramesa romana (Hymenoptera: Eurytomidae), on biomass of the invasive weed,Arundo donax (Poaceae: Arundinoideae), and on revegetation of riparian habitat along the Rio Grande in Texas

An invasive grass, Arundo donax, occupies thousands of hectares of arid riparian habitat along the Rio Grande in Texas and Mexico, and has negative impacts on national security, water resources, and riparian ecosystems. The shoot-tip-galling wasp Tetramesa romana was released in 2009 between Brownsville and Del Rio, Texas, and has dispersed over 800?km along the river channel. Plots along the river were surveyed for shoot counts of arundo and all other plant species in 2016 at seven sites in regions in which prior studies had documented a 22% decline in arundo biomass (estimated from live shoot length) from 2007 to 2014. Estimated live biomass declined a further 32% between 2014 and 2016. Native plants accounted for 86% of the 44 species encountered in plots. Individual plots averaged five plant species, and arundo was most abundant in only 9 of 21 plots. Arundo live biomass and shoot density were negatively associated with plant diversity, indicating that live arundo interferes with germination and/or survival of other plant species. The proportion of dead shoots in plots, proportion of wasp-galled shoots, and density of exit holes made by emerging adult wasps per metre live main shoot length were positively associated with plant diversity in a combined model. Regressions indicated that the effects of wasp damage measures on diversity were mediated through their effects on main shoot mortality. By reducing live arundo biomass, the arundo wasp is fostering recovery of native plant communities at riparian sites along the Rio Grande.     

毛竹（Phyllostachys pubescens）竹笋群动态的研究

 本文从克隆植物生长的调节与适应的角度,研究了毛竹竹笋群的时空动态。竹笋的单位面积产量及个体大小在年际之间变化很大。环境有利的年份出土的竹笋要比条件恶劣的年份多得多、高得多、壮得多。而且,自始至终较早的同生群的竹笋总比较晚的同生群的要高得多、壮得多。较早的同生群的竹笋刚出土时要经历一段生长缓慢的时期,而较晚的同生群的竹笋一出土生长就十分迅速。不管竹笋何时出土,它们几乎都同时进入最快生长期。竹笋高度日增量最快时可达每天100cm左右。本文解释了亚热带竹子在春季不同时间出土的竹笋为何及如何几乎同时抵达林冠顶部。最后,提出了一些有利于竹林经营管理的建议。     

The Effect of Number of Shoots on the Quantity and Distribution of Increment in Young Apple-trees: With three Figures in the Text

It is shown that the shoots of a young tree act additively ratherthan competitively, that is, each extra shoot produces a definiteextra increment in total weight, not that a constant incrementis divided among the shoots of the young tree. One-year apple-trees of 3 varieties were rigorously selectedfor size and weight, and in the spring disbudded to 1, 2, 3,or n, the natural number of shoots per plant. The treatmentswere applied in the 1st or 2nd year after planting and the incrementduring the treatment year was determined. Provided not morethan a few secondary shoots were produced on the current shoots,each additional primary shoot produced an increase in weight.In one variety plants with 1 primary shoot produced many secondariesand these plants were heavier than those with 2 primaries. The largest shoot was not greatly affected in size by the presenceof other shoots except in the variety which produced secondaryshoots readily. These were most abundant on plants with 1 primaryshoot, fewer on plants with 2, and almost negligible on plantswith 3 and n shoots. Treatment and varietal effects on the percentage distributionof increment as leaves, new stem, old-stem increment, and root,were small. The percentage of leaves in the 2nd year was abouthalf what it was in the 1st year; the percentage of root wasnearly the same in both years.     

汶川地震对大熊猫主食竹——拐棍竹竹笋生长发育的影响

为了了解汶川地震对大熊猫主食竹生长发育的影响,2009年10月—2011年4月,在地震重灾区四川龙溪-虹口国家级自然保护区内设置150个样方,就地震强度、中度、轻度干扰对大熊猫主食竹拐棍竹(Fargesia robusta)竹笋生长发育的影响进行了研究。研究结果显示:(1)发笋物候上,地震强度干扰的发笋时间(Julian时间)较中度和轻度干扰显著推迟,而发笋期不受影响。(2)发笋量和当年生幼竹数是拐棍竹更新生长的数量指标。地震强度和中度干扰样方的发笋量都显著高于轻度干扰,而发笋量在强度和中度干扰间差异不显著;地震强度干扰样方的当年生幼竹数显著高于中度和轻度干扰,中度和轻度干扰样方间差异不显著。这说明地震的强度和中度干扰都有利于拐棍竹竹笋和当年生幼竹数量的更新。(3)基径和株高是拐棍竹更新生长的质量指标。强度干扰下拐棍竹的基径和株高都显著小于中度和轻度干扰,中度干扰样方的基径与轻度干扰差异不显著,但株高显著矮于轻度干扰样方。表明强度干扰下拐棍竹的质量最差,中度干扰的基径已基本得到恢复,但株高仍受到抑制。(4)地震不同干扰等级拐棍竹退笋原因划分为:外力机械损伤、动物取食、生长停止、其他4种。对地震不同干扰等级拐棍竹退笋原因比率的分析发现,强度干扰样方因外力机械损伤和生长停止退笋的比率显著高于中度和轻度干扰样方,而因动物取食退笋的比率显著低于中度和轻度干扰样方。证明强度干扰样方的竹笋更容易受到外力机械损伤和生长停止退笋,而中度和轻度干扰的竹笋更倾向于动物取食致退,揭示了拐棍竹的生长是与震后不同程度的干扰相适应的。     

Heavy metal uptake by arbuscular mycorrhizas of Elsholtzia splendens and the potential for phytoremediation of contaminated soil

A pot culture experiment and a field experiment were carried out separately to study heavy metal (HM) uptake from soil contaminated with Cu, Zn, Pb and Cd by Elsholtzia splendens Nakai ex F. Maekawa inoculated with arbuscular mycorrhizal (AM) fungi and the potential for phytoremediation. The HM-contaminated soil in the pot experiment was collected from the field experiment site. Two AM fungal inocula, MI containing only one AM fungal strain, Glomus caledonium 90036, and M II consisting of Gigaspora margarita ZJ37, Gigaspora decipens ZJ38, Scutellospora gilmori ZJ39, Acaulospora spp. andGlomus spp., were applied to the soil under unsterilized conditions. In the pot experiment, the plants were harvested after 24 weeks of growth. Mycorrhizal colonization rate, plant dry weight (DW) and P, Cu, Zn, Pb, Cd concentrations were determined. MI-treated plants had higher mycorrhizal colonization rates than MII-treated plants. Both MI and MII increased shoot and root DW, and MII was more effective than MI. In shoots, the highest P, Cu, Zn and Pb concentrations were all observed in the plants treated with MII, while MI decreased Zn and Pb concentrations and increased P but did not alter Cu, and Cd concentrations were not affected by either of two inocula. In roots, MII increased P, Zn, Pb concentrations but did not alter Cu and Cd, and MI did not affect P, Cu, Zn, Pb, Cd concentrations. Cu, Zn, Pb, Cd uptake into shoots and roots all increased in MII-treated plants, while in MI-treated plants, Cu and Zn uptake into shoots and Cu, Zn, Pb, Cd into roots increased but Pb and Cd uptake into shoots decreased. In general, MII was more effective than MI in promoting plant growth and HM uptake. The field experiment following the pot experiment was carried out to investigate the effects of MII under field conditions. The 45-day-old nonmycorrhizal and MII-colonized seedlings of E. splendens were transplanted to HM-contaminated plots and harvested after 5 months. MII-inoculation increased shoot DW and shoot P, Cu, Zn, Pb concentrations significantly but did not alter shoot Cd concentrations, which led to higher uptake of Cu, Zn, Pb, Cd by E. splendens shoots. These results indicate that the AM fungal consortium represented by MII can benefit phytoextraction of HMs and therefore play a role in phytoremediation of HM-contaminated soils.     

Wild edible plants of the Sikkim Himalaya: Nutritive values of selected species

Wild edible plants form an important constituent of traditional diets in the Himalaya. In the Sikkim Himalaya a total of 190 species have been screened as edible species out of which nearly 47 species come to the market. The present paper deals with nutritive values of 27 most commonly consumed wild edible plants in the Sikkim Himalaya. Of 27 plant species that were analyzed for their nutritive values, 22 were edible for their fruits and five for leaves/shoots. Among different plant parts, generally higher nutrient concentration was recorded for leaves, followed by new shoots and fruits. For different species the crude fiber content ranged between 2.15–39.90%, and the total soluble salts between 4.66–21.00%, and the vitamin C content from 6–286 mg/100 g. The fat content was determined high in the fruits ofCastanopsis hystrix, Machilus edulis, andCinnamomum species, while the protein content was highest inHippophae rhamnoides, Cucumis melo, andEleagnus latifolia. The total carbohydrate content ranged from 32–88% in the fruits of various wild edibles, the reducing sugar from 1.25–12.42%, total sugar from 2.10–25.09%, the lignin content varied from 9.05–39.51%, the hemicellulose between 25.63–55.71% and cellulose content varied from 9.57–33.19% in different species. Among the various macronutrients estimated in the plant samples of different wild edible species, nitrogen was present in highest quantity, followed by potassium, calcium, magnesium, phosphorus, and sodium. Micronutrients, such as iron, zinc, magnesium, and copper contents were analyzed in different plant parts of various wild edible species. The iron content was higher in leaves and new shoots. The nutritive values of certain wild edible species determined in this study are comparable with various commercial fruits. It is suggested that a few wild edible species need to be grown for commercial cultivation and adopted in the traditional agroforestry systems, which will lead to reduced pressure on them in natural forest stands as well as producing economic benefits for poor farmers.     

Differential Responses of two Bamboo Species (Phyllostachys Auresulcata `Spectabilis' and Pleioblastus Chino `Hisauchii') to Excess Copper

Pot experiments were carried out to examine the responses of growth, physiological properties, copper (Cu) absorption and translocation in two bamboo species, Phyllostachys auresulcata ‘Spectabilis’ and Pleioblastus chino ‘Hisauchii’ Two-year old plants with similar size were exposed to excess Cu treatments, in order to demonstrate their Cu tolerance and potential ability of phytoremediation under Cu-polluted soil as biofuel feedstock. Pots were irrigated with aqueous solutions of Cu in concentrations of 500, 1000 and 2000 mg CuSO₄·5H₂O kg^?1, against the control (tap water). Plant growth, chlorophyll contents, photosynthesis rate, malondialdehyde (MDA) content, Cu concentrations in leave, stem and root, and Cu contents in shoot per pot were measured after transplanted plants were grown under excess Cu treatments for 60 days. Two bamboo species had different responses to tolerance and allocation of supplied Cu. As Cu treatments rose, the percentage of senescent shoot and MDA content increased, and the chlorophyll content and photosynthetic capacity decreased. Such changes in Hisauchii were more obvious than in Spectabilis. However, number of emerged shoots did not differ between the two species across four Cu treatments. In the efficiency of decontamination, Hisauchii was more effective than Spectabilis, since either the Cu concentrations in leaves, stems and roots or Cu contents in shoot per pot in Cu treatments from 500 to 2000 mg?kg^?1 were higher in Hisauchii than in Spectabilis It is suggested that the potential capability of absorbing Cu might cause the different response to cu stress between the two bamboo species. Both bamboo species can be considered to exhibit enough potential to develop in Cu-polluted areas of China as bioenergy resources and phytoremediation plants.     

Induced defences in the neotropical tree Bauhinia brevipes (Vog.) to herbivory: effects of damage-induced changes on leaf quality and insect attack

Induced defences to herbivory are physical, nutritional, and allelochemical traits that change in plants following damage or stress, and that reduce the performance and/or preference of herbivores. The aim of this study was to verify the occurrence and effect of induced responses in Bauhinia brevipes (Vog.) (Leguminosae) which defend it against herbivores, through the manipulation of its leaves, and their effects on herbivore foraging behaviour. We selected 15 plants in the field, and three shoots per plant were subjected to one of three treatments: (1) damaged shoots (simulation of the main types of foliar herbivory and insect exclusion); (2) damaged control shoots (insect exclusion); and (3) control shoots (not manipulated). Water and nitrogen content, tannin concentration, levels of herbivory, and shoot growth rates were compared among treatments. Leaf quality varied among treatments. Damaged leaves showed higher tannin concentration, and lower water and nitrogen content compared to undamaged leaves. On the other hand, they experienced higher rates of herbivory than leaves on control shoots. Moreover, shoots that were experimentally induced showed a higher increase in final shoot length. These results suggest that simulated herbivory on B. brevipes reduced the nutritional quality of its leaves and increased the amount of secondary compounds, therefore altering insect herbivore attack and increasing shoot performance.     

施肥对毛竹（Phyllostachys pubescens）竹笋生长的影响

 毛竹(Phyllostachys pubescens)为具有重要经济价值的高大乔木状竹种。本文通过完全随机化区组施肥试验,探讨了施肥量及施肥方式对毛竹竹笋生长的效应。结果表明：在毛竹林内施肥可使出笋数和活笋数提高3倍以上,但对竹笋(幼竹)的个体大小却几乎没有改良效果。竹笋的存活率基本上是恒定的,不随施肥量的改变而改变。当地下茎(竹鞭)穿越养分分布不均的环境时,竹笋能有选择地大量长于养分丰富的地段而避开养分贫乏的地段。另一方面,跨越于有利地段和不利地段的竹(笋)株间有明显的生理整合作用,而且这种生理整合在显著增加了长在不利地段的竹笋数(高收益)的同时,基本上没有减少长在有利地段的竹笋数(低耗费)。9m×9m的样方已足以观测到显著的施肥效果,这比传统的毛竹研究中使用的1亩的样方面积效率要高。在竹林培育方面,不均匀施肥如带状或点状施肥要比均匀施肥效率高。