In artificially controlled pot experiments, perennial ryegrass was mixed with other leguminous plants (white clover and alfalfa) and treated with lead, zinc and cadmium (337 mgkg-1, 648 mgkg-1, and 9 mgkg-1, respectively) to simulate compound pollution conditions. The results showed that the concentrations of heavy metals, transport factors, and bioconcentration factors in mixed planting of ryegrass decreased compared with those in monoculture. Regardless of whether heavy metal pollution was introduced, mixed planting increased the aboveground and underground biomasses of ryegrass. The different mixed planting treatments had no significant impact on the chlorophyll concentration of ryegrass. The mowing time, mixed planting treatment, and heavy metal treatment had impacts on antioxidant and osmotic adjustment substances, and there were some interactions. The mixed planting treatment did not significantly affect glutathione concentration, cysteine concentration, or nonprotein thiol. Mixed planting generally increased the nitrogen and phosphorus concentrations of ryegrass while reducing the stoichiometric ratio of carbon, nitrogen, and phosphorus. These results suggest that the mixed planting of ryegrass with legumes promotes the growth of ryegrass in the presence of high concentrations of heavy metal pollution. However, it does not enhance the ability of ryegrass to remediate heavy metal pollution in the soil.

Thirty-six leaf samples of Sophora davidii , Indigofera amblyantha , and Broussonetia papyrifera were collected during different growth periods. The dynamic changes in nutritional components and secondary metabolites were analysed, and the biological activities of the secondary metabolites were evaluated. The optimal utilization stage of each plant was comprehensively determined. The results showed that S. davidii (the crude protein (CP) content 24.82%, relative feed value (RFV) 186.52) and I. amblyantha (CP 24.28%, RFV 177.54) were premium forage materials and that B. papyrifera (CP 21.65%, RFV 133.84) was a first-level forage. The best period for using the leaves of these three plants as animal feed was the flowering stage. As the growth progressed, the contents of CP, crude fibre (CF), dry matter (DM), and nitrogen-free extract (NFE) decreased, while the CF, neutral detergent fibre (NDF), acid detergent fibre (ADF), and crude ash (Ash) increased. The S. davidii , I. amblyantha , and B. papyrifera contains total flavonoid (0.36-0.70, 1.072.87, and 0.59-0.78 mg/g, respectively), tannin (5526.21-7717.77, 4284.03-5818.73, and 6390.66-7640.60 nmol/g, respectively), total phenol (205.62-298.69, 163.22-214.22, and 143.87-214.34 mg/g, respectively), total saponin (0.110.22, 0.20-0.39, and 0.10-0.16 ng/g, respectively) and total alkaloid (0.20-0.32, 0.23-0.38, and 0.20-0.36 ng/g, respectively). Moreover, the tannins, total phenols, saponins, flavonoids, and alkaloids in these woody forages scavenged hydroxyl radicals and superoxide anions to varying degrees, and their ability to reduce Fe 3+ gradually increased with concentration. These plants inhibited hyaluronidase and albumin denaturation. The alkaloid and flavonoid extracts of S. davidii significantly ( P<0.05 ) inhibited Staphylococcus aureus with antibacterial diameters of 14.48 and 14.44 mm, respectively. The flavonoid (11.29 mm) and tannin (11.17 mm) extracts of S. davidii significantly ( P<0.05 ) inhibited Escherichia coli. The alkaloid (12.29 mm) and tannin (13.15 mm) extracts of B. papyrifera , and the flavonoid extract of S. davidii (13.44 mm) and I. amblyantha (10.32 mm) inhibited Bacillus subtilis . The secondary metabolites of these plants possess antioxidant, anti-inflammatory and antibacterial activities. In conclusion, these findings provide new perspectives on the nutritional value and biochemical characteristics of leaves of S. davidii , I. amblyantha , and B. papyrifera , emphasizing their use as valuable feed source for ruminants.

课程思政是振兴本科教育和提高人才培养质量的重要措施.植物生理学课程作为一门植物生产类相关专业的专业基础课,具有课程思政的优势.文章分析了植物生理学课程思政的意义、教学改革的思路及思政元素的挖掘,结合课程每一篇章具体分析了可挖掘的人文内涵,从增强专业认知感、增强爱国情怀、培养科学思维、培养社会责任感和树立正确的"三观"方面探索思政教育融合,为植物生理学课程进行思政教学提供参考与借鉴.

Abstract Aims: To investigate the toxic effects of heavy metals on perennial ryegrass, their accumulation characteristics and detoxification by perennial ryegrass and soil microbial contents were examined under different planting treatments. Method: Through artificially controlled pot experiments, perennial ryegrass was mixed with other herbs (white clover and alfalfa) and treated with lead, zinc and cadmium (337 mg·kg-1, 648 mg·kg-1, and 9 mg·kg-1, respectively) to simulate complex pollution conditions. Results: The results showed that mixed-species planting increased the aboveground and belowground biomass of perennial ryegrass compared to single-species planting. Both mowing and mixed planting affected the physiological parameters of the plants. Mixed planting reduced the lead, zinc and cadmium contents in perennial ryegrass. Under the uncontaminated treatment, mixed planting increased the activity of soil microorganisms, but under heavy metal contamination, mixed planting did not increase the soil microbial activity. This showed that mixed planting promoted ryegrass growth but did not improve its remediation. Conclusion: Considering these effects and economic factors, it was concluded that perennial ryegrass monoculture has the best remediation effect on lead-, zinc-, and cadmium-polluted soil.

To investigate the effects of low phosphorus stress on five endogenous hormones(abscisic acid,gibberellin,growth hormone,zeatin and solanum lactone)in the roots and leaves of Pueraria lobata,and to pro-vide a reference for the selection and breeding of low phosphorus tolerant Pueraria species.Kudzu from different provenances(Australian Kudzu,Hunan Kudzu from China and Jiangsu Kudzu from China)were selected as ex-perimental materials,and the hydroponic experiments with three phosphorus nutrient levels were conducted(nor-mal phosphorus 0.5 mmol·L-1,low phosphorus 0.05 mmol·L-1 and extremely low phosphorus 0.005 mmol·L-1 KH2 PO4 concentrations were set).The contents of endogenous hormones in roots and leaves of Kudzu seed-lings were determined by enzyme-linked immunoassay.The results showed that the abscisic acid content of kudge root decreased with the decrease of P concentration,and the abscisic acid content of Kudzu leaf decreased first and then increased with the decrease of P concentration.The contents of gibberellin,zeatin,growth hormone and monocrotaline in kudzu root increased with the decrease of P concentration.The contents of gibberellin and growth hormone in Kudzu leaf also increased with the decrease of P concentration,and the contents of zeatin and dictamnolide first increased and then decreased with the decrease of P concentration.

通过盆栽试验,研究铅(Pb,337 mg·kg-1)、锌(Zn,648 mg·kg-1)、镉(Cd,9 mg·kg-1)复合污染条件下,多年生黑麦草(Lolium perenne L.)单种、高羊茅(Festucaelata Keng ex E.Alexeev)单种以及多年生黑麦草和高羊茅混种(1:1)方式下,多年生黑麦草和高羊茅对Pb-Zn-Cd复合污染的生理响应.结果显示:在Pb-Zn-Cd复合胁迫下,高羊茅单种具有较好的抗逆性,多年生黑麦草和高羊茅1:1混种使多年生黑麦草有较好的抗逆性.结果表明:在Pb-Zn-Cd污染下,混种提高了多年生黑麦草对重金属污染的抗性,通过诱导多年生黑麦草活性氧清除系统以及可溶性糖和可溶性蛋白含量的增加来应对Pb-Zn-Cd胁迫带来的活性氧代谢失衡和缺水对植物的伤害,通过提高多年生黑麦草非蛋白巯基和还原型谷胱甘肽的含量来缓解Pb-Zn-Cd胁迫带来的毒性效应;混种高羊茅对Pb-Zn-Cd的抗性在Pb-Zn-Cd胁迫下没有显著提高.

为揭示葛藤(Pueraria lobate)幼苗对低磷胁迫的适应机制,选取来自澳大利亚和我国湖南和江苏的3个不同种源的葛藤为试验材料,设置0.5(常磷)、0.05(低磷)和0.005(极低磷)mmol· L-13种不同KH2PO4浓度处理,测定不同磷处理下3个不同种源葛藤幼苗的生长及生理响应.结果 表明,0.05 mmol· L-1磷处理下,3个不同种源葛藤的根长、根表面积、根直径等根系指标和叶面积、叶周长等叶片指标均呈显著上升趋势(P＜0.05),表明葛藤具有一定的耐低磷性;在0.005 mmol· L-1磷处理下,湖南和江苏葛藤的根系指标较澳大利亚葛藤受到了明显抑制,但湖南葛藤的叶片形态指标呈增长趋势.3个不同种源葛藤在低磷胁迫下的根和叶中脯氨酸、可溶性糖、丙二醛含量及抗氧化酶活性均显著增加(P＜0.05),但可溶性蛋白含量下降.综上所述,澳大利亚葛藤的耐低磷能力强,具有较高的种植推广价值.

为了解多年生黑麦草对Pb、Zn、Cd的耐性和土壤重金属污染的修复潜力,采用砂培法研究铅(Pb)、锌(Zn)、镉(Cd)对多年生黑麦草生长发育及生理生化特性的影响.Pb2+设0(CK)、500(Pb500)、l 000(Pb1000)、2 000 mg?kg-1(Pb2000)四个处理,Zn2+设0(CK)、500(Zn500)、1 000(Zn1 000)、2 000 mg?kg-1(Zn2000)四个处理,Cd2+设0(CK)、10(Cd10)、20(Cd20)、50mg·kg-1(Cd50)四个处理,测定不同浓度Pb2+、Zn2+、Cd2+胁迫下多年生黑麦草的形态特征、叶绿素含量、抗氧化酶活性、膜脂过氧化产物含量、渗透调节物质含量,利用Fuzzy隶属函数法对这些指标进行综合评价.结果表明:①Pb2+、Zn2+、Cd2+胁迫显著抑制多年生黑麦草的生长,Pb2000、Zn2 000和Cd50三个处理对黑麦草的生物量、分蘖及根系生长的抑制作用最显著.②Pb2+、Zn2+和Cd2+胁迫时,多年生黑麦草会通过增加植物的渗透调节物质和抗氧化酶活性减缓对植物的伤害.超氧化物歧化酶、过氧化物酶活性均随着Pb2+、Zn2+和Cd2+胁迫浓度的增加呈现先增加后减少趋势;丙二醛和脯氨酸含量随着重金属浓度增加而增加;Pb500和Cd10处理的可溶性糖含量下降,而Zn500处理的可溶性糖含量增加.(3)多年生黑麦草对Pb2+、Zn2+和Cd2+胁迫有一定的耐受性,不同处理的植株抗逆性由强到弱依次表现为:Zn500＞CK＞Zn1000＞Cd10＞Pb500＞Zn2000＞Cd20＞Pb1000＞Pb2000＞Cd50.研究结果为生态恢复提供理论支撑和数据支持.

种子萌发期是植物最易受到干旱影响的时期.为揭示葛藤种子对干旱胁迫的适应机制,比较了聚乙二醇(PEG)-6000溶液在-0.2 MPa、-0.4 MPa、-0.6 MPa、-0.8 MPa、-1.2 MPa、蒸馏水(CK)渗透势下葛藤种子的发芽率、发芽势、发芽指数、活力指数及胚芽胚根长度和干重的变化.结果表明:随着PEG浓度的增大,葛藤种子的发芽率、发芽势、发芽指数、活力指数、胚芽胚根长、胚芽胚根干重均呈现显著下降趋势,说明葛藤种子在干旱胁迫下萌发能力、萌发速度及幼苗生长能力均受到不利影响;胚芽胚根的长度比呈现先升高后降低趋势、胚芽胚根的干重比呈现一直降低的趋势,揭示了葛藤种子在萌发期有增加胚根中营养物质积累,提升胚根生长能力来适应干旱胁迫的趋势.

[目的]探究铅(Pb)、锌(Zn)、镉(Cd)单一及复合污染对多年生黑麦草生长和生理特性的影响,为检验多年生黑麦草对土壤重金属污染的抗性能力提供科学依据.[方法]采用沙培法,研究CK(不加任何重金属盐)、Pb、Zn、Cd单一及复合胁迫对多年生黑麦草株高、叶宽、根长、生物量及光合色素含量、脯氨酸(Pro)、过氧化物酶(POD)、超氧化物歧化酶(SOD)、可溶性糖(SS)和丙二醛(MDA)等生理指标的影响,利用隶属函数对生长和生理指标进行综合评价.[结果]Pb-Zn-Cd处理对多年生黑麦草株高、叶宽、根长、分蘖数、地上生物量、地下生物量、根冠比、POD活性和SOD活性影响最大,其中株高、叶宽、根长、分蘖数、地上生物量、地下生物量和根冠比较CK分别下降61.9％、35.9％、66.5％、72.1％、92.8％、94.2％和20.1％,POD和SOD活性较CK分别增加64.6％和3.8倍.Zn处理对多年生黑麦草的叶绿素a含量、类胡萝卜素含量、叶绿素总量和光合色素总量的影响最大,较CK分别显著下降28.6％、31.9％、20.6％和22.9％(P<0.05,下同),而对叶绿素b含量抑制最大的是Cd处理,其次是Pb-Zn-Cd处理,较CK分别下降20.3％和20.0％;所有重金属处理均使多年生黑麦草Pro含量显著增加;SS和MDA含量受Zn-Cd处理抑制最明显,较CK分别显著增加56.4％和7.0倍;复合胁迫对多年生黑麦草各指标的影响存在交互作用.通过隶属函数综合评价可知多年生黑麦草对各处理的耐受性为:Zn>CK>Cd>Zn-Cd>Pb-Zn>Pb>Pb-Cd>Pb-Zn-Cd.[结论]多年生黑麦草对Zn胁迫存在一定的耐受性,而对Pb-Zn-Cd复合胁迫的耐受性最差.

为了解油杉河牧场建立对植被动态的影响,给研究区畜牧业的可持续发展和草地资源的开发利用提供科学依据,以贵州省油杉河牧场为研究区域,将野外实地测量21个样方的覆盖度与每个采样点的7种植被指数(NDVI,DVI,RVI,EVI,SAVI,GVI,OSAVI)建立相对应回归模型,比较每种植被指数与覆盖度之间的相关性,然后选择最佳覆盖度估算模型估算研究区近30年覆盖度,定量分析年际覆盖度变化的特征,探讨了研究区覆盖度与气象因子的相关性.结果 表明,所建估算模型中线性模型和二次多项式模型相关性高于其他模型,其中植被指数SAVI的二次多项式模型精度高达90.27％,说明该模型具有可行性;1993年～2019年油杉河牧场覆盖度整体呈上升趋势,2006年和2015年上升幅度最大;近30年研究区覆盖度在月际水平上与温度、降水的相关性随着人类活动的增加呈逐渐减小趋势,牧场建立以后相关性不显著.人类活动对油杉河牧场植被覆盖度具有深远影响,推荐植被指数SAVI估算温暖湿润地区的人工草地覆盖度.

以葛藤为材料,研究不同渗透势(CK、-0.2MPa、-0.4MPa PEG-6000)下葛藤种苗的保护性酶活性(CAT、POD、SOD)及MDA、可溶性糖、可溶性蛋白含量的变化,拟揭示葛藤适应干旱的生理机制.结果表明:随着干旱胁迫的增强,CAT、POD活性呈现上升趋势;SOD活性呈先上升后下降趋势;MDA和可溶性蛋白含量都有所升高,而可溶性糖含量先降低后升高.说明干旱胁迫均有利于提高葛藤种苗活性氧清除系统中的CAT、POD和SOD的酶活性,提高可溶性蛋白和可溶性糖的含量,来缓解干旱胁迫对葛藤种苗造成的膜脂过氧化伤害.

为揭示多花黑麦草(Lolium multiflorum Lamk)对不同钙磷环境的适应机制,设置3个不同钙磷比(1∶1、2∶1、5∶1),每个钙磷比下设置两种钙磷浓度,以不添加钙和磷的营养液处理为对照,探讨不同钙磷水平下多花黑麦草形态和生理指标的变化;并利用隶属函数综合评价法来筛选适宜多花黑麦草生长的钙磷配比及浓度.结果 表明:①Ca/P比为1∶1时,随Ca2+、P浓度的增加,株高、叶宽、光合色素和脯氨酸(proline,Pro)含量均呈下降趋势,丙二醛(malondialdehyde,MDA)和超氧化物歧化酶(superoxide dismutase,SOD)活性呈升高趋势;②Ca/P比为2∶1时,随Ca2+、P的增加,株高、叶宽存在一定的下降,叶绿素含量、MDA含量和SOD活性差异不显著,类胡萝卜素和Pro含量升高;③Ca/P比为5∶1时,随Ca2+、P浓度的增加,株高、叶宽、光合色素含量升高,MDA含量下降,Pro含量和SOD活性变化不明显;④P浓度相同时,随着Ca2+浓度的增加,叶绿素、类胡萝卜素含量和SOD活性呈降低趋势;⑤通过隶属函数综合评价,多花黑麦草适宜生长的Ca、P浓度分别为50和10 mg·kg-1.以上结果为多花黑麦草的栽培种植和钙磷响应机理研究提供理论依据.

对不同供磷水平下多花黑麦草(Lolium multiflorum)生长初期生长特性的变化进行分析,筛选耐磷指标,为多花黑麦草耐磷机制的研究和生产实践提供基础理论依据.利用主成分分析和模糊数学隶属函数分析6个不同供磷水平(0、2.5、5.0、10.0、25.0、50.0 mg/kg)对多花黑麦草生长特性的影响并进行综合评价;用株高、叶宽、叶绿素a含量等8个指标的耐磷系数和综合评价值(D)进行灰色关联分析.结果表明,随着磷水平的增加,株高、叶宽、叶绿素a含量、叶绿素b含量、类胡萝卜素含量、脯氨酸含量呈现先上升后下降的趋势,丙二醛含量和超氧化物歧化酶(SOD)活性呈现先下降后上升的趋势;多花黑麦草最适生长的磷水平为10.0 mg/kg;与耐磷性最相关的指标为超氧化物歧化酶活性、脯氨酸含量、株高、叶绿素a含量.

贵州大学草业科学专业以学校实施通识教育改革为契机,对专业课程、个性课程、创新创业课程及实践等教学内容进行了不断改革与探索、调整与优化,增强了基本理论和基本技能的专业培养体系,同时具有较宽领域和较强适应能力的专门人才培养方式.

为探明多花黑麦草(Lolium multiflorum)种子在钙(Ca)盐胁迫下的耐受性,研究了不同Ca2+浓度(0,5,10,20,40,100mmol·L-1)对多花黑麦草种子萌发和幼苗生长的影响,并利用隶属函数综合评价出适宜多花黑麦草生长的浓度.结果表明:随着Ca2+浓度的增加,发芽势、发芽率、发芽指数、根长和苗长呈下降趋势,苗、根的干重和鲜重呈先上升后下降趋势,根苗比、根冠比、盐害率、根抑制率和苗抑制率呈上升趋势.Ca2+浓度为5mmol·L-1条件下,幼苗和幼根的干重和鲜重都达到了最大值.在各浓度处理之间根苗比和根冠比差异不显著(p＞0.05).隶属函数综合评价得出适宜多花黑麦草种子萌发的Ca2+浓度为5mmol·L-1,为高Ca2+土壤条件下栽种多花黑麦草提供科学依据.

In order to reveal the adaptation mechanism of Italian Ryegrass to high levels calcium and low levels of phosphorus environment in karst habitat, nine different ratios of calcium and phosphorus were set. The changes in the seed germination indexes and seeding growth indexes of ryegrass under different calcium and phosphorus ration were analyzed, and the ratios of calcium and phosphorus suitable for the seed germination and seeding growth of ryegrass was screened by the comprehensive evaluation of subordinate function. The results showed that the different calcium and phosphorus ratios had no significance effect on the relative moisture content of shoots and roots(p>0.05). Compared to shoots, it had greater inhibitory effect on roots. When the Ca concentration was10 mmol/L, the germination rate, germination index, vigor index, germination potential, root length(RL), shoots length(SR) and SL/RL, the fresh weight and dry weight of shoots and the fresh weight of roots decreased at first and then increased, while relative salt injury rate and root dry weight increased at first and then decreased and rootshoot ratio was increased with the increase of P concentration. When the P concentration was 5 mmol/L, rootshoot ratio was increased, and the germination rate, germination potential, germination index, vigor index, shoot length, root length, the fresh weight and dry weight of shoots at first decreased and then increased, at last decreased by the increase of Ca concentration. Through the comprehensive evaluation of the membership function, the ratio of calcium and phosphorus to suitable seed germination and seedlings growth of Italian Ryegrass was 5 mmol/L∶5 mmol/L. The results of this study could provide theoretical basis for the cultivation of Italian ryegrass in the southwestern region.

为充分发挥豆科植物在生态恢复与重建中的作用,调查了贵州省境内石漠化部分地区的野生多花木蓝根瘤资源.结果表明:隶属于干热河谷南亚热带季雨林生态区的野生多花木蓝根瘤菌及内生细菌资源较为丰富;野生多花木蓝的共生结瘤率只达50％左右,根瘤全部着生于寄主的侧根及须根上,大小可达0.5～3.0mm;12株根瘤菌分布在6个属10个种,其中慢生根瘤菌属(Bradyrhizobium)的分布频率最高41.67％,慢生根瘤菌属的B.japonicum和伯克霍尔德菌属Burkholderia bacterium的发生频率最高16.67％;16株根瘤内生细菌分布在4个属11个种,其中芽孢杆菌属(Bacillus)的分布频率最高43.75％,芽孢杆菌属的B.megaterium的发生频率最高31.25％.

互联网技术的发展,推动着教学模式的改革.国家宏观政策的支持、"互联网+"技术的支撑、"互联网+教育"的显著优势,使得基于"互联网+"翻转专业基础课教学模式成为可能.利用"互联网+",课前通过"云平台+APP"的方式构建互动平台;课上以任务为中心,构建多层次间反复互动的学习小组;课下,师生角色转换的教学模式,实现教学资源的信息化共享,充分挖掘和培养学生的自主学习能力.

Questions(1) What are the primary factors determining the precipitation-use efficiency (PUE) in northern Tibet; (2) how does PUE respond to the gradients of biotic and abiotic factors; and (3) how do the composition and structure of plant functional groups (PFGs) affect PUE?LocationNorthern Tibet, China.MethodsA community survey of species composition, cover and above-ground net primary productivity (ANPP) was conducted within 1mx1m plots in 62 slightly disturbed sites. The effects of community features (total cover, cover of PFGs and species richness) and environmental factors [mean annual precipitation (MAP), mean annual temperature, surface soil bulk density, pH and C and N content] on PUE were identified through Pearson's correlation analyses, hierarchical partitioning and ordinary regressions.ResultsAlong the precipitation gradient, ANPP and PUE increased exponentially. Among the community features, total cover and cover of PFGs, including forbs and sedges, were the primary factors that determined PUE. The three cover variables, together with species richness, positively affected PUE and accounted for 47.6% of the total variation in PUE. Among the environmental factors, MAP, surface soil pH and N content were the most significantly related to PUE and accounted for 29.9% of the total contribution.ConclusionCommunities with high cover, species richness and nutrient content, but low soil bulk density, presented the highest PUE. At a regional scale, PUE depended mainly on plant cover, especially the cover of PFGs, namely, forbs and sedges. Environmental factors, including MAP and surface soil N and C content, positively affected PUE, whereas soil pH and bulk density negatively affected PUE. Our results highlight the importance of considering community structure to understand PUE variations in natural alpine grasslands.