Boehmeria nivea var. strigosa (Urticaceae), a new variety from Southwest China

Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly characterized by its green abaxial leaf blade,partly connate stipules,and densely patent strigose hairs on stems and potioles.The phylogenetic analysis based on rbc L,nrDNA and rbc L+nrDNA datasets,revealed that all individuals of B.nivea var.strigosa formed a monophyletic group.The conservation status of B.nivea var.strigosa is assessed as“Near Threatened”(NT)according to IUCN evaluation criteria.The discovery of this new variety is not only crucial for the taxonomy of ramie,but also provides reference for the exploration and utilization of ramie.

Photo-temperature response of ramie (Boehmeria nivea (L.) Gaud.) male sterile lines

Six male sterile lines (MSLs) of ramie (Boeh-meria nivea (L.) Gaud.) were grown in dark rooms under the photoperiods of 9.5h, 11h or 12.5h d-1 in spring and summer seasons (dif-ferent environmental temperatures) to test their developmental response to photoperiod and temperature. The MSLs showed little difference in vegetative growth duration, but different de-velopment rates in the reproductive growth stage under the tested conditions. Higher tem-perature (grown in summer) mainly accelerated vegetative growth, while the short photoperiod treatment accelerated the reproductive growth of the MSLs. Moreover, the short photoperiod treatment combined with higher temperature obviously accelerated both the vegetative and reproductive growth of the MSLs. But the effect of higher temperature decreased, or even dis-appeared along with the photoperiod elongation. The MSLs were divided into 5 photo-temperature response types, based on the flower budding acceleration of short pho-toperiod and the approximate temperature re-sponse index.

镉胁迫对苎麻(Boehmeria nivea)根系及叶片抗氧化系统的影响

镉(Cd)是非必需和毒性最强的重金属元素之一,不合理的开发利用可导致土壤受到Cd的严重污染,严重危及土壤环境或水环境。以苎麻为材料,采用模拟镉(Cd)污染盆栽培养法,选择21 d和49 d等2个不同胁迫期,测定不同浓度Cd2+胁迫下苎麻根系与叶片中渗透调节物质含量、超氧化物岐化酶(SOD)活性、过氧化物酶(POD)活性、过氧化氢酶(CAT)活性、丙二醛(MDA)含量及根系活力的变化。结果表明,高浓度胁迫49 d后,苎麻根系中的渗透调节物质含量明显高于叶片含量,且极显著高于对照,并在240 mg·L^(-1)Cd处理下出现最高值;胁迫49 d时,根系与叶片的渗透调节物质含量与Cd2+浓度极显著正相关。在2个不同胁迫周期,苎麻根系的SOD与POD活性均明显高于叶片;在胁迫21 d时,根系的CAT活性低于叶片,而胁迫49 d后,则明显高于叶片;胁迫21 d时,苎麻根系与叶片的抗氧化酶活性均较胁迫49 d要高;胁迫49 d时,根系POD活性与Cd2+浓度呈极显著正相关,表明根系POD酶在抗氧化酶中占主导地位。不同胁迫时长下苎麻根系或叶片的MDA含量变化趋势不明显,但根系或叶片受胁迫21 d后的MDA含量随Cd2+浓度增加的波动相对受胁迫49 d后的更明显,表明植物早期生理功能出现暂时性的修复。2个不同胁迫周期内,不同浓度镉胁迫下苎麻的根系活力均比对照组下降。研究显示,苎麻根系与叶片对镉胁迫的应答机制不同,且在不同胁迫时间下的响应机理差异较大,根系表现出更强的耐受能力。

德兴铜矿区优势物种苎麻(Boehmeria nivea)对重金属的富集与积累特性

选取江西省德兴铜矿区8个采样点,对土壤和苎麻植株Cd、Pb和Cu含量进行测定分析。结果表明,铜矿区土壤中Cu污染严重并伴有轻微的Cd污染,Pb含量则在江西省土壤背景值范围之内。8个样点土壤Cd、Pb和Cu含量均值分别为0.51、9.36和1 058.21 mg·kg-1。大部分样点苎麻植株叶片中重金属含量最低,根最高,最高值与最低值差距达数十倍,地上部重金属含量低于地下部。苎麻对上述3种重金属的富集系数和转运系数从大到小依次为Cd、Pb和Cu;苎麻对Cd的富集系数和转移系数最高值分别为1.42和0.54,对Pb的富集系数和转移系数最高值分别为0.63和0.53,对Cu的富集系数和转移系数最高值分别为0.08和0.37。8个样点苎麻的地上部生物量均值为1.41 t·hm-2,最高值达2.18 t·hm-2。苎麻对Cd、Pb和Cu的累积量均值分别为0.2、1.1、24g·hm-2。因此,苎麻对Cu和Cd具有一定的耐性,在矿区种植苎麻可作为植物修复的先锋物种,促进矿区生态恢复。

苎麻(Boehmeria nivea L)叶片愈伤组织诱导与植株再生的研究

为了建立苎麻外源DNA导入和遗传转化的实验体系，本试验以“湘苎3号”为材料，就激素、培养方法、培养条件对叶片外植体脱分化与再分化的影响作了较系统的研究。试验结果表明：1．较低浓度（0．1mg／l）的NAA能加快叶片启动。较高浓度（2．0～3．0mg／1）的BA有利于叶组织脱分化和愈伤组织形成，并能促进芽的再生，但BA浓度过高则抑制愈伤组织和芽的生长发育。2．NAA与BA配合使用能改善愈伤组织的质量和生长速度，促进芽的形成，高浓度BA与适当浓度NAA配合能分化丛生芽。配合使用时NAA与BA表现了互作效应，其互作效应受光温条件的影响。3．低温短光照预处理能提早叶组织启动；低温短光照预处理和昼夜温差预处理均能显著提高叶外植体分化成芽率；暗培养能促进愈伤组织分化和芽的发生。

Inhibition of hepatitis B virus production by Boehmeria nivea root extract in HepG2 2.2.15 cells

AIM: To explore the anti-hepatitis B virus (HBV) effects of Boehmeria nivea (B. nivea) root extract (BNE) by using the HepG2 2.2.15 cell model system. METHODS: Hepatitis B surface antigen (HBsAg), hepatitis B virus e antigen (HBeAg), and HBV DNA were measured by using ELISA and real-time PCR, respectively. Viral DNA replication and RNA expression were determined by using Southern and Northern blot, respectively. RESULTS: In HepG2 2.2.15 cells, HBeAg (60%, P < 0.01) and particle-associated HBV DNA (> 99%, P < 0.01) secretion into supernatant were significantly inhibited by BNE at a dose of 100 mg/L, whereas the HBsAg was not inhibited. With different doses of BNE, the reduced HBeAg was correlated with the inhibition of HBV DNA. The anti-HBV effect of BNE was not caused by its cytotoxicity to cells or inhibition of viral DNA replication and RNA expression. CONCLUSION: BNE could effectively reduce the HBV production and its anti-HBV machinery might differ from the nucleoside analogues.

Study on the Relationship Between Sex Differentiation and Ethylene in Ramie

To explore the role of ethylene in sexual determination in ramie, the ethylene release rates in ramie stem apex of different sex, bud of the same node in female and hermaphrodite ramie in the second crop, and single inflorescence of different sex in hermaphrodite ramie were measured by gas chromatography. Effects of two ethylene inhibitors on sex expression in ramie were investigated. The ethylene release rate of stem apex was higher in the second crop or female ramie than that in the third crop or hermaphrodite ramie during growth. Although ethylene release rates between lower nodes and higher nodes were little different, it was lower in the middle nodes in hermaphrodite ramie. The ethylene release rates were higher in the higher nodes of female ramie at the second crop. At the third crop, the ethylene release rates were higher in lower nodes, lower in middle nodes and then highest in higher nodes in female ramie. However, an opposite ethylene release pattern was observed in hermaphrodite ramie. The ethylene release rate was higher in female flower than male flower and mixed inflorescence in hermaphrodite ramie. The male flower could be distinctly induced by AVG （aminooethoxyvinylglycine）. The node of the first male flower, percentage of female flowers and ratio of female flowers to male in ramie were evidently depressed by AVG in contrast to water. The percentage of mixed male and female flowers was also increased and the percentage of female flower decreased by spraying AgNO3. There was a close relationship between sexual differentiation and ethylene release rate in ramie. The female ramie could be induced by high ethylene release rate. The female flower could be inhibited by AVG and AgNO3. AVG at a concentration of 300 mg L^-1 was most effective.

Studies on the Morphologic Characteristics and Economic Traits of Different Ploidy Materials of Ramie

Different ploidy ramie materials were studied via microscopic observation on stem sections and macerated fiber cells. Morphologic differences between different ploidy plants were analyzed. Average bark area percentages in ramie stem transection of haploids, tetraploids, diploids and triploids were 28. 91, 27. 05, 26. 97 and 24.77% respectively. Average percentages of fiber layer area of diploids, haploids, tetraploids and triploids were 16.80, 16. 58, 15.52 and 13.78% respectively. Average fiber cell diameter and cell wall thickness were increased along with the increase of the ploidy of the plants. Average fiber length of diploids, triploids and haploids were 8. 49, 7. 96 and 6. 93 cm respectively. Average L/B (length/breadth) of diploids, triploids and haploids were 2 470. 7, 2 390. 6 and 1 616.3 respectively. Average breadths of fiber of haploids, diploids and triploids were 29. 30, 33. 87 and 49. 20μm respectively. However, there were relatively large variations in the above characteristics among the ramie materials of the same ploidy levels. Field performance of different ploidy plants was also investigated. As the chromosome ploidy increasing, there was a tendency of declining in shoot number per plant and increasing in stem diameter. Average shoots per plant of haploids, diploids, triploids and tetraploids were 5.83, 5.30, 3.77 and 3. 65 whereas their average stem diameters were 0.66, 0. 67, 0. 74 and 0. 76 cm respectively. Triploids were the tallest, while haploids were the shortest. Triploids had strong growth vigour, diploids and tetraploids had moderate growth vigour, while haploids appeared to be lack of growth vigour. Cold stress tolerance of tetraploids were the strongest, diploid had the moderate tolerance, while haploids and triploids were the least tolerant to cold stress. Both haploids and triploids were sterile.

干旱胁迫下苎麻生理指标和抗逆相关基因表达的变化

为研究干旱胁迫对苎麻(Boehmeria nivea L.)生理特性和抗逆相关基因的影响,以苎麻品种华苎4号为试验材料,采用自然干旱胁迫,测定其生理指标、抗逆相关基因表达量和相关农艺性状的变化。结果表明,与对照相比,干旱胁迫处理苎麻叶片叶绿素SPAD降低,茎尖和叶片的相对电导率、游离脯氨酸含量、丙二醛含量和可溶性糖含量均显著增加(P<0.05),超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)的活性均升高,抗逆相关基因BnP5CS1、BnWRKY1、BnACO1、Bn-α-amylase、BnAPX1、BnbZIP1、BnDREB19和BnGR1的相对表达量均提高,其中BnP5CS1和BnWRKY1在叶片中的相对表达量分别提高了5.1倍和5.3倍;与对照相比,干旱胁迫处理苎麻株高、茎粗、皮厚、地上部鲜重和单株原麻重均显著下降(P<0.05),茎粗和皮厚分别降低0.13 cm和0.14 mm,地上部鲜重和单株原麻重分别降低了52.05%和39.53%。

环保包装专用苎麻品种筛选

根据轻型环保包装材料的苎麻[Boehmeria nivea(L.)Gaudich.]品种要求,2021—2022年对现有国内审定的8个苎麻品种进行农艺性状调查、纤维支数测定、抗性鉴定等研究,筛选出具有中等抗性以上、纤维支数2000公支以上、纤维产量3750 kg/hm^(2)以上的品种苎麻。对抗性、产量、纤维支数综合分析,根据分析结果从8个品种中筛选出中苎1号、赣苎6号、华苎6号3个适宜环保包装专用的苎麻品种。

Analysis of Genetic Relationship among Boehmeria Varieties Using cpSSR Markers

By using cpSSR （chloroplast microsatellites） markers, the genetic relationship among Boehmeria varieties was analyzed. Five pairs of cpSSR primers with excellent amplification result, clear amplification band and good repeatability were screened from 22 pairs of cpSSR primers, and the polymorphism rate was 22.73%. By using these five pairs of cpSSR primers, 16 polymorphic loci were amplified from eight experimental materials, with an average of 3.2 loci. According to the results of duster analysis, these experimental materials were divided into three categories. The clustering results were consistent with the classification results based on chloroplast gene sequences.

宜机化种植模式下苎麻收获机械的选型

为提供苎麻[Boehmeria nivea(L.)Gaud.]机械化收获技术和装备支持,促使快速解决苎麻收获难的瓶颈问题,在湖北省咸宁市向阳湖基地苎麻头麻收获期,选取4LZ-130型圆盘切割式苎麻收割机、4GM-185型饲用苎麻收割机和4MZK-200型苎麻联合收割机3种机型进行苎麻收割效率、割茬高度、漏割情况、出现故障情况和平均故障间隔时间的机械选型试验。结果表明,4MZK-200型苎麻联合收割机作业质量更接近相关行业标准,更适宜高效种植模式下苎麻机械化收获,其收割效率为0.5 hm2/h、割茬高度为8 cm、漏割率为0.7%、故障诊断误诊率为0.7%、平均故障间隔时间为112 h。

苎麻耐镉品种差异及其筛选指标分析

以营养液盆栽试验结合田间微区试验调查9个苎麻品种耐镉差异并筛选耐镉指标。结果表明,营养液盆栽试验中,不同镉处理下苎麻株高、单株叶片数、地上部干重和地下部干重差异显著,各性状具有较大的品种间差异。地上部干重与株高、叶片SPAD值和地下部干重均呈显著或极显著正相关,相关系数分别为0.95、0.82和0.85。田间微区试验中,地上部干重与株高、茎粗、皮厚均呈显著或极显著正相关,相关系数分别为0.86、0.72和0.76。分别对营养液盆栽试验和微区试验各指标耐镉指数的隶属函数值进行聚类分析,9个品种均被分为3类,结果基本一致。说明以营养液盆栽苎麻的株高、叶片SPAD值、地下部干重和地上部干重作为指标筛选苎麻耐镉品种是一条有效途径。

苎麻基因组微卫星的分离与鉴定(英文)

以苎麻[Boehmeria nivea（L．）Gaud．]栽培品种芦竹青为材料，经Mse Ⅰ酶切并与相应接头连接，然后与生物素标记的探针（CT）15杂交，再用链亲和素包被磁珠（Dynabeads M-280）捕捉杂交产物，以21碱基接头寡核苷酸为引物经PCR扩增获得了双链目的片段，回收300—1000bp DNA片段，然后克隆到pMD18-T载体上，转化至DH5α中，这样就构建了苎麻富含（GA）n微卫星的部分基因组文库。随机挑取36个克隆，以锚定简单重复序列为引物对其进行PCR筛选。测序分析了22个阳性克隆，每个克隆都含有微卫星DNA，阳性克隆率为61．1％，微卫星种类以与探针互补的（GA／CT）n为主，占83．3％，同时还存在（TG／AC）n和三碱基、六碱基为单元构成的苎麻微卫星，如（GAC）n、（ACG）n、（TCT）n、（TCG）n、（GAA）n、（CCGACG）n、（GAGAAA）n等。最后以18个微卫星位点设计了18对苎麻微卫星特异引物。GMCT重复单元的长度从7到40范围内变化，平均为19．2，显示了它们将产生良好多态性，为一种强有力的遗传标记。苎麻微卫星DNA标记可广泛应用于苎麻基因型鉴定，基因和QTL分析，分子标记辅助育种，系谱分析等。

不同倍性苎麻的细胞学观察

化学药剂诱导的苎麻孤雌生殖后代植株的染色体数目变化很大 ,有单倍体、混倍体和非整倍体细胞 .在 2 8株孤雌生殖后代植株中 ,有 6株单倍体细胞超过 50 % .秋水仙素诱变株及多倍体杂交后代的染色体数目也呈现多样性 ,不同植株甚至同一植株的染色体数目均不一致 ,变化在 12～ 84之间 .对不同倍性苎麻植株分生组织的有丝分裂行为 ,观察到三极分裂、不均等分裂和落后染色体等异常有丝分裂现象 ,并对造成这种现象的原因作了初步的探讨 .

苎麻CCoAOMT基因全长cDNA克隆与序列分析

目的试图分离和克隆苎麻内源咖啡酰辅酶A甲基转移酶基因。方法采用RACE技术克隆基因,对序列应用ClustaW1.82软件进行在线分析,将苎麻mRNA序列、mRNA编码区序列以及氨基酸序列与已报道的其它植物的相应序列进行多重序列排列比较并构建系统树。结果获得了苎麻CCoAOMTcDNA全长序列(GenBank注册号:AY651026);苎麻咖啡酰辅酶A甲基转移酶是氧甲基转移酶类;苎麻CCoAOMT基因mRNA序列与已报道的其他植物的相应序列不能聚为一类,其差异明显大于其它植物间的差异。苎麻CCoAOMT基因mRNA编码区序列与玉米(Zeamays:ZMA242980、ZMA242981)的同源性高于其他植物。推导的苎麻CCoAOMT酶蛋白氨基酸序列与杨树(Populusbalsamifera:AJ224894、AJ224896)、美洲山杨(Populustremuloides:PTU27116)的同源性高于其他植物。结论苎麻CCoAOMT基因cDNA与其它植物的相应序列具有同源性。

Cd/Sb/Pb复合污染对苎麻生长及吸收富集特征的影响

通过盆栽试验,分析了不同浓度Cd/Sb/Pb复合作用下苎麻的生长响应及重金属吸收、富集和迁移特征变化。结果表明,低浓度Cd/Sb/Pb复合处理对苎麻生长及生物量没有产生明显影响,而高浓度条件下则产生明显抑制效应,株高变矮,茎粗变细及生物量明显减少。苎麻体内Cd、Pb和Sb吸收量与污染土壤具有直接相关性,随复合处理浓度增加明显增大。至最高污染浓度处理时,苎麻体内重金属吸收量以Cd〉Sb〉Pb,地上部含量分别达335.74 mg/kg、157.55 mg/kg和92.31 mg/kg。复合处理下苎麻地上部对Cd、Sb和Pb的富集系数分别在0.67~0.88、0.13~0.17和0.05~0.06之间,均表现为随复合处理浓度增加而减少变化。苎麻Cd、Sb和Pb的转运系数分别为0.81~0.92、0.38~0.46和0.53~0.73,其中Cd、Sb的转运系数随复合处理浓度增加而增大,Pb则随复合处理浓度增加而减少。苎麻对重金属Cd/Sb/Pb复合污染具有较好吸收累积及转运能力,相比生物量小的植物而言,是目前修复重金属Cd/Sb/Pb复合污染的理想植物。

苎麻对镉毒害的生理耐性机制及外源精胺的缓解效应

采用盆栽试验方法,研究了不同浓度Cd胁迫下苎麻体内的生理代谢变化。结果表明,营养生长期苎麻对Cd的忍耐阈值为80mg·kg-1左右,Cd胁迫在此浓度范围内时,苎麻叶绿素、类胡萝卜素和可溶性蛋白质含量均有不同程度的增加,且抗坏血酸-谷胱甘肽循环中四个关键指标值--还原型抗坏血酸和还原型谷胱甘肽含量、抗坏血酸过氧化物酶和谷胱甘肽还原酶活性均上升,表明苎麻通过加速该循环清除活性氧,使植株避免氧化伤害;高于此浓度的Cd胁迫使苎麻抗氧化防御体系遭到破坏,生理代谢趋于紊乱。证明苎麻最适宜的外源精胺浓度为0.5×10-4mol·L-1,喷施该浓度精胺可显著提高不同浓度Cd胁迫下苎麻叶绿素、类胡萝卜素和可溶性蛋白质的含量,有效地抑制膜脂过氧化,极大地提高了谷胱甘肽与抗坏血酸的含量,同时使谷胱甘肽还原酶和抗坏血酸过氧化物酶的活性明显增强,从而使整个抗氧化循环高效运转,这对于增强苎麻对Cd的抗性是至关重要的。

应用隶属函数法评价33个苎麻资源的营养品质

为筛选出适宜的饲用苎麻(Boehmeria nivea)品种,对国家苎麻种质资源圃中33个苎麻资源的主要营养成分进行了测定,并利用隶属函数法对其营养价值进行综合评价。结果表明,33个苎麻资源主要营养平均含量为粗蛋白17.70%、粗脂肪2.60%、粗纤维24.97%、粗灰分13.83%、磷0.35%、钙3.56%。根据隶属函数分析结果,将33个苎麻品种分为3级,第Ⅰ级为综合营养品质优质型5个苎麻品种,Ⅱ级为品质中等型25个品种,Ⅲ级为品质差型3个品种。研究结果表明采用隶属函数法综合评估苎麻的营养品质是可行的,可以较好地揭示其综合营养品质,为饲用苎麻品种选育提供参考。

分离克隆苎麻CCoAOMT基因部分序列

以苎麻[Boehmeria nivea(L.)Gaud]为材料,研究木质素代谢的关键酶苎麻咖啡酰辅酶A甲基转移酶基因序列。分离了高纯度RNA和DNA。以RNA为模板,用简并引物以RT-PCR的方法,克隆了苎麻CCoAOMT基因cDNA部分序列,长度为486 bp,编码162个氨基酸残基。此cDNA序列为苎麻植物中首次克隆的(caffeoyl-CoA 3-O-methyltransferase,CCoAOMT)新基因序列。GenBank注册,登录号为AY651026。以苎麻4个栽培品种基因组DNA为模板,经温度梯度PCR条件优化,获得苎麻CCoAOMT基因的部分基因组序列,GenBank注册号为AY818191(湘苎3号,922 bp)、AY822619(圆麻,915 bp)、AY822620(芦竹青,914 bp)、AY822622(青麻,914 bp)。生物信息学分析结果发现,苎麻4个栽培品种的CCoAOMT基因基因组DNA片段序列有一定的差异。