多效唑对紫穗槐生长的调节效应

以紫穗槐(Amorpha fruticosa)为试材,采用土施多效唑的方法,研究了不同浓度多效唑(10、50、100、150、200mg·L~(-1))对紫穗槐生长的影响,以探究多效唑对紫穗槐的作用机制。结果表明:多效唑可有效地抑制紫穗槐的株高生长,增粗紫穗槐的基径,显著增加其可溶性糖和可溶性蛋白质含量,提高过氧化物酶(POD)活性,降低丙二醛(MDA)含量。表明多效唑可有效地改善紫穗槐的形态特征,通过改善其渗透调节能力、抗氧化性和光合物质等提高其抗性,采用隶属函数法对紫穗槐各项指标进行综合评价,得出150mg·L~(-1)多效唑处理效果最佳。     

植物延缓剂对杨柴抗旱性的调控作用

以通过盆栽试验获得的一年生杨柴幼苗为试材,利用叶绿荧光参数分析不同浓度多效唑(0、150、300、450、600mg·L~(-1))对杨柴幼苗抗旱性的影响,以期筛选出提高杨柴抗旱性的最佳多效唑浓度。结果表明:轻度干旱条件下,150~600mg·L~(-1)多效唑处理对杨柴的ETR、Yield、Fv/Fm、Fv′/Fm′、Fv/Fo表现为促进作用,且促进作用随多效唑浓度升高先加强后减弱,多效唑浓度过高则会显著抑制qN(P0.05)。采用隶属函数法对杨柴各项荧光指标进行综合评价,得出300mg·L~(-1)的多效唑对一年生杨柴幼苗抗旱性的增强效果最佳。     

植物卷材不同肥水配比对紫穗槐生理特性的影响

以两河口水电站植物护坡工程为背景,以种植紫穗槐的植物卷材为研究对象,把不同施肥梯度和水分配比作为变量因子,探究紫穗槐的生理指标变化趋势,为该区域植物护坡材料的水肥设计提供参考依据。结果表明:当保水剂一定,施肥浓度为12g·m~(-2)时,紫穗槐叶片中丙二醛含量增加,植物叶片中的过氧化物酶活性减少,可溶性蛋白质含量增多,植物的叶片保水力也最强。当施肥量一定时,保水剂量为10g·m~(-2)时,可溶性蛋白质含量最少,保水剂量追加到15g·m~(-2),此时的可溶性糖含量最多,植物叶片中的丙二醛含量增加,植物叶片保水力也随之增加。     

植物生长调节剂和蔗糖浓度对狼爪瓦松愈伤组织生物量及有效物质积累的影响

以狼爪瓦松愈伤组织为试材,采用正交实验的方法,研究了MS基本培养基浓度及6-苄氨基腺嘌呤(6-BA)、萘乙酸(NAA)2种植物生长调节剂对狼爪瓦松愈伤组织生物量和有效物质含量的影响;同时,对适宜的蔗糖浓度进行了筛选。结果表明:MS+3.5mg·L~(-1) 6-BA+0.1mg·L~(-1) NAA组合,最有利于愈伤组织生长和多糖、总酚及黄酮的积累;MS+3.5mg·L~(-1)6-BA+0.1mg·L~(-1) NAA培养基中加入30g·L~(-1)的蔗糖时,愈伤组织生长最佳,有效物质含量最高,在此蔗糖浓度下狼爪瓦松愈伤组织可生产711.2mg·L~(-1)多糖、165.1mg·L~(-1)总酚和154.5mg·L~(-1)黄酮。     

华南地区几种常见植物的耐淹性研究

以华南地区几种常见植物为例,研究了人工模拟淹水胁迫对植物叶绿素和脯氨酸含量的影响。结果表明:在实验周期内(28d),红绒球(Calliandra haematocephala Hassk.)和朱蕉(Cordyline fruticosa(L.)A.Cheval.)长势较好,叶绿素均呈现前期短暂波动上升、后逐渐下降的趋势,脯氨酸前半期下降或趋于平衡,后半期呈上升趋势;紫叶狼尾草(Pennisetum setaceum'Rubrum')和朱槿(Hibiscus rosa-sinensis Linn.)的长势稍弱,耐淹条件下分别存活至7d和4d。因此红绒球和朱蕉可作为优选植物用于受水分影响较大的滨水缓冲带地区。     

两种表面活性剂对镉胁迫下龙葵生理特性的影响

以镉污染土壤为试材,以龙葵为研究对象,采用盆栽试验,分别研究了不同浓度鼠李糖脂和皂角苷对镉(Cd)胁迫下龙葵(Solanum nigrum L.)生物量、株高和生理指标的影响。结果表明:在镉胁迫下,随着鼠李糖脂和皂角苷浓度的增加,龙葵的株高、生物量、叶绿素a(chl a)、叶绿素b(chl b)、总叶绿素含量、过氧化物酶(POD)、超氧化物歧化酶(SOD)活性以及可溶性蛋白质含量呈现先增高后降低的趋势,游离脯氨酸、丙二醛(MDA)含量升高,而可溶性糖含量则呈现降低的趋势。在单独施加鼠李糖脂的条件下,较低浓度鼠李糖脂(0.25、0.50g·L~(-1))能够提高龙葵植株的株高和生物量,缓解重金属Cd对龙葵的毒害,并在鼠李糖脂浓度为0.50g·L~(-1)时,缓解毒害的作用最为明显;而高浓度鼠李糖脂(5.00、7.50g·L~(-1))则会加剧对龙葵的毒害。而单独施加皂角苷则在处理浓度≤5.00g·L~(-1)时促进龙葵的生长,尤以皂角苷浓度为5.00g·L~(-1)时的效果最好,但效果并不显著;当皂角苷浓度为7.50g·L~(-1)时,则会抑制龙葵的生长。综合来看,鼠李糖脂的处理效果优于皂角苷。     

基质中添加不同浓度多效唑对甘蓝幼苗生长的影响

以甘蓝H-60为材料,采用穴盘育苗的方法,将5种浓度（0.125、0.25、0.5、1.0、1.5 mg/L）多效唑添加到育苗基质中,研究不同浓度多效唑对甘蓝幼苗生长的影响。研究结果表明,基质中添加1 mg/L多效唑能有效降低甘蓝幼苗株高,缩短下胚轴长。综合幼苗的茎粗、株高、生物量、下胚轴长、壮苗指数等各项生长指标,基质中添加多效唑浓度为0.125 mg/L和1.0 mg/L时,能有效提高甘蓝幼苗的壮苗指数,有利于培育甘蓝壮苗。     

利用均匀设计法优化天麻萌发菌小菇属真菌(Mycena sp.)培养基的研究

小菇属真菌(Mycena sp.)是天麻种植的重要萌发菌,系统研究小菇属真菌的营养生长因子需求,对天麻产业具有重要应用价值。本研究以小菇属真菌菌落直径和生物量同时增加作为优化目标,利用均匀设计法对影响真菌生长的14个营养因子进行配比优化,获得的最优培养基配方为:可溶性淀粉4 g·L~(-1)、蛋白胨4 g·L~(-1)、酵母膏4 g·L~(-1)、甘露醇8 mg·L~(-1)、烟酸4 mg·L~(-1)、 KH_2PO_41.6 g·L~(-1)、 MgSO_4·7H_2O 1.6 g·L~(-1)。在25℃, pH5.5培养21d,菌落直径达到69 cm,生物量为0.2685 g。可溶性淀粉和KH_2PO_4,蛋白胨和酵母膏间的交互作用对菌落直径有显著影响;蛋白胨和MgSO_4·7H_2O,甘露醇和MgSO_4·7H_2O间的交互作用对生物量大小有显著影响。研究结果表明影响小菇属真菌生长的营养因子较多,且其多被因子间的交互作用影响。     

比久和多效唑对矮牵牛生长和观赏品质的影响

以盆栽矮牵牛为试验材料,研究了4~5片真叶期不同浓度比久和多效唑处理对矮牵牛生长和观赏品质的影响。结果表明:250~1 500mg·L~(-1)的多效唑各处理引起明显药害,植株不开花;250~1 500mg·L~(-1)的比久各处理均能较显著促进矮牵牛的营养和生殖生长,综合比较,750~1 000mg·L~(-1)比久处理的促进作用效果佳,尤其是750mg·L~(-1)比处理的促进作用最好,可以显著提高盆花矮牵牛的观赏品质。     

杀菌剂对草莓灰霉病菌的毒力测定及田间防效

以"甜查理"草莓为试材,草莓灰霉病菌(Botrytis cinerea)为供试菌,采用菌丝生长速率法,研究了12种杀菌剂对草莓灰霉病菌的影响。结果表明:室内毒力试验中,50g·L~(-1)己唑醇SC的毒力最强,EC_(50)值为0.051 9mg·L~(-1);500g·L~(-1)异菌脲SC、430g·L~(-1)戊唑醇SC和400g·L~(-1)氟硅唑EC对草莓灰霉病菌也有很好的抑制作用。田间试验中,50g·L~(-1)己唑醇SC对草莓灰霉病的防治效果最好,防治效果达81.57%~85.42%;500g·L~(-1)异菌脲SC、430g·L~(-1)戊唑醇SC和400g·L~(-1)氟硅唑EC对草莓灰霉病也具有较好的防治效果,防治效果均在74%以上;10%多抗霉素WP和3%中生菌素WP对草莓灰霉病也有一定的防治效果,防效均能达到65%以上。     

Fruit growth,cuticle deposition,water uptake,and fruit cracking in jostaberry,gooseberry, and black currant

Fruit cracking after rain limits the production of a number of crops, including some Ribes species. To gain a better understanding of the factors involved in cracking, fruit growth, deposition of the cuticular membrane (CM), water uptake and fruit cracking were studied in black currant (Ribes nigrum L. cv. Zema), gooseberry (Ribes uva-crispa L. cv. Rote Triumph), and jostaberry (Ribes nidigrolaria B. cv. Jostine). Fruit surface area and fresh mass increased continuously throughout development, whereas deposition of the CM was biphasic. CM mass per fruit increased rapidly up to 42, 41, and 49 days after full bloom (DAFB) in black currant, gooseberry, and jostaberry, respectively. Thereafter, CM mass per fruit remained constant in gooseberry and jostaberry or increased at a lower rate in black currant. The cessation of or reduced rate of CM deposition resulted in a decrease in CM mass per unit area in all berries. Elastic strain of the CM at maturity averaged 23.8% and 19.5% in gooseberry and jostaberry, respectively, and only 8.2% in black currant. Microcracks in the CM were observed first in gooseberry and jostaberry 64 DAFB, whereas there were no microcracks in black currant. Water uptake into mature detached berries was linear over 2 h of incubation. Rates of uptake were highest in gooseberry followed by black currant and jostaberry. Relative uptake was similar via the cut end of the pedicel (32.1%), the apex of the fruit (34.7%) and the fruit surface (33.2%). Rates of water uptake through the fruit surface were positively related to surface area. Average fruit water potential for black currant, gooseberry, and jostaberry was −2.14 ± 0.17, −1.24 ± 0.03, and −1.89 ± 0.20 MPa, while the permeability for osmotic water uptake was 7.7 ± 0.4 × 10⁻⁸, 5.2 ± 0.1 × 10⁻⁸, and 3.3 ± 0.3 × 10⁻⁸ m s⁻¹. Incubating whole fruit in deionized water for 72 h resulted in more cracked jostaberries (94%) than black currants (74%) or gooseberries (50%). A comparison of our findings in Ribes berries with published data for the sweet cherry drupe revealed that the berries fitted the relationships established in sweet cherry among fruit growth, cuticle deposition, strain of the cuticle, microcracking, permeability for osmotic water uptake, frequency of stomata and cracking. The Ribes berries were less susceptible to cracking than sweet cherry.     

Similitude,similarity, and scaling

An exceptionally rich and colorful literature, drawn in almost equal parts from pure mathematics, from the sciences, and from the technologies, has grown up over the years, which bear in different ways on the topics under discussion. It is the intent of the present paper to survey this far-flung literature, point out some of the commonalities and interrelationships which underlie it, and briefly indicate how it has been and can be applied. To my knowledge, this kind of review has not been attempted before.     

Wetlands, carbon, and climate change

Wetland ecosystems provide an optimum natural environment for the sequestration and long-term storage of carbon dioxide (CO₂) from the atmosphere, yet are natural sources of greenhouse gases emissions, especially methane. We illustrate that most wetlands, when carbon sequestration is compared to methane emissions, do not have 25 times more CO₂ sequestration than methane emissions; therefore, to many landscape managers and non specialists, most wetlands would be considered by some to be sources of climate warming or net radiative forcing. We show by dynamic modeling of carbon flux results from seven detailed studies by us of temperate and tropical wetlands and from 14 other wetland studies by others that methane emissions become unimportant within 300 years compared to carbon sequestration in wetlands. Within that time frame or less, most wetlands become both net carbon and radiative sinks. Furthermore, we estimate that the world’s wetlands, despite being only about 5–8 % of the terrestrial landscape, may currently be net carbon sinks of about 830 Tg/year of carbon with an average of 118 g-C m^?2 year^?1 of net carbon retention. Most of that carbon retention occurs in tropical/subtropical wetlands. We demonstrate that almost all wetlands are net radiative sinks when balancing carbon sequestration and methane emissions and conclude that wetlands can be created and restored to provide C sequestration and other ecosystem services without great concern of creating net radiative sources on the climate due to methane emissions.     

Climatic, landform, microtopographic, and overstory canopy controls of tree invasion in a subalpine meadow landscape, Oregon Cascades, USA

Tree invasions have been documented throughout Northern Hemisphere high elevation meadows, as well as globally in many grass and forb-dominated ecosystems. Tree invasions are often associated with large-scale changes in climate or disturbance regimes, but are fundamentally driven by regeneration processes influenced by interactions between climatic, topographic, and biotic factors at multiple spatial scales. The purpose of this research was to quantify spatiotemporal patterns of meadow invasion; and how climate, larger landforms, topography, and overstory trees have interactively influenced tree invasion. We combined airborne Light Detection and Ranging (LiDAR) characterizations of landforms, topography, and overstory vegetation with historical climate, field measurements of snow depth, tree abundance, and tree ages to reconstruct spatial and temporal patterns of tree invasion over five decades in a subalpine meadow complex in the Oregon Cascade Range, USA. Proportion of meadow occupied by trees increased from 8?% in 1950 to 35?% in 2007. Larger landforms, topography, and tree canopies interactively mediated regional climatic controls of tree invasion by modifying depth and persistence of snow pack, while tree canopies also influenced seed source availability. Landscape context played an important role mediating snow depth and tree invasion; on glacial landforms tree invasion was negatively associated with spring snowfall, but on debris flows tree invasion was not associated with snow fall. The importance of snow, uncertain climate change impacts on snow, and mediation of snow by interacting and context dependent factors in complex mountain terrain poses substantial hurdles for understanding how these ecotones may respond to future climate conditions.     

Up-regulation of mRNA expressions of fas,bcl-2, bim,bax, caspase-3, caspase-9, and bcl2l12 in K562 treated with bortezomib

AIM: To detect the treatment of K562 leukemia cells with bortezomib altering the expression of genes fas, bcl-2, bcl2l12, bim, bax, caspase-9 and caspase-3.METHODS: MTT assay was used to detect the inhibition of proliferation. Apoptosis was detected by Annexin-V staining and mitochondrial transmembrane potential (Δψm). RT-PCR was used to analyze the mRNA expressions of fas, bcl-2, bcl2l12, bim, bax, caspase-3 and caspase-9.RESULTS: Bortezomib caused a time- and dose-dependent inhibition of cell proliferation and IC50 of 24 h and 48 h were 161.41 nmol/L and 96.33 nmol/L, respectively. At the concentration of 104 nmol/L, bortezomib induced apoptosis in a time-dependent manner, including increasing annexin-V positivity and decreasing the Δψm. RT-PCR showed that bortezomib up-regulated the mRNA expression of fas, bcl2l12, caspase-9 and caspase-3, but mRNA expressions of bcl-2, bim and bax did not changed obviously.CONCLUSION: Bortezomib inhibits the proliferation of K562 and induces apoptosis, in which fas, bcl2l12, caspase-9 or caspase-3 gene is one of the main genes taking part in.     

氮磷钾硼肥配施对青花菜养分吸收分配及产量和品质的影响

研究了不施肥处理,氮磷钾配施和增施硼肥对青花菜养分吸收分配及产量和品质的影响。结果表明,现蕾期至花球膨大期,青花菜对氮、磷、钾的吸收量最大,整个生长期对钾的吸收最多,氮次之,磷最少。氮磷钾主要分配在叶片中,现蕾后逐渐向花球转移,从现蕾到采收时,叶片中氮、磷、钾分配率分别降低了19.6%、10%和9.0%,花球中氮磷钾分配率分别提高了23.1%、15.9%和11.1%。不施氮、磷、钾肥显著降低了花球产量、维生素C含量和成品率,增施硼肥处理的花球成品率较氮磷钾肥处理提高了4.8%,不施氮肥和钾硫肥(K₂SO₄)显著降低了花球中的硫代葡萄糖苷含量。相关性分析表明,青花菜产量与植株内氮、钾积累量显著正相关,成品率与植株内磷营养显著正相关。     

Principles for forcing tulips,hyacinths, daffodils,Easter lilies and Dutch irises

Systematic investigations on the forcing of tulips, hyacinths, daffodils, Easter lilies and Dutch iris have produced a fairly complete set of scientific principles. In this review, these principles have been classified into a 3-phase concept of forcing. These are: production, programming, and greenhouse. The production phase is defined as all processes which occur during bulb production and it terminates with the harvesting of the bulbs. The programming phase comprises all handling of the bulbs from harvesting until they are placed under greenhouse conditions. The greenhouse phase is the accelerated development of the bulbs until anthesis or marketing of the plants. These phases have been discussed relative to floral and root development and the basic environmental requirements of the bulb species.