叶面喷施胺鲜酯及其与油菜素内酯复配液对油用牡丹生理特性及产量的影响

为筛选出适合油用牡丹高产高效栽培中的植物生长调节剂应用技术,本试验以凤丹为材料,分别于盛花期(4月7日)、籽粒形成期(4月18日)、果荚与籽粒快速生长期(5月10日)叶面喷施不同质量浓度的胺鲜酯(D1、D2和D3)及其与油菜素内酯复配液(BD1、BD2和BD3),研究其对植株生理特性、籽粒产量指标(百粒重、单果籽粒重、单株籽粒重及籽粒产量)的影响。结果表明,与对照组相比,喷施植物生长调节剂处理的牡丹叶片生理特性和籽粒产量关键参数均有明显提高:7月3日时,BD2处理叶片SOD活性较对照显著提高5.24%;5月19日和7月3日时,所有处理叶片MDA含量均较对照显著降低;7月3日时,所有处理叶片可溶性糖含量与对照均有显著性差异,其中BD2处理最高,较对照增加33.84%;6月10日时,所有处理叶片总叶绿素含量均显著高于对照,其中BD3处理增幅最大,为98.11%;3个测定时期,除6月10日的BD3处理外其他处理叶片净光合速率均显著高于对照,且随着胺鲜酯质量浓度的提高呈现先增加后降低趋势。所有处理单株籽粒重及籽粒产量均显著高于对照,其中BD3增幅均最大,分别为10.45%与10.44%。相关性分析表明,SOD活性与Chl a、Chl b、Car、总叶绿素含量和净光合速率呈极显著正相关,与可溶性糖含量呈显著正相关,与MDA含量呈极显著负相关;总叶绿素含量与净光合速率呈极显著正相关,净光合速率与单果籽粒重、单株籽粒重和籽粒产量呈显著正相关。综之,12、16 mg/L胺鲜酯与0.05 mg/L油菜素内酯复配喷施油用牡丹植株的生理特性表现优异,并可获得较高籽粒产量。

外源油菜素内酯对铅胁迫下花生幼苗的缓解效应

油菜素内酯(EBR)作为第六大植物激素,具有缓解植物抗逆性的效应。为探究EBR对Pb胁迫下植物生理特征的缓解效应,试验以花生为材料,采用土壤盆栽法,测定了不同质量浓度Pb胁迫下花生种子萌发、形态指标,以筛选出最适Pb胁迫质量浓度,研究在该质量浓度下外源施加EBR(0、0.01、0.05、0.10、0.50、1.00 mg/L)对花生的种子萌发、幼苗形态指标和生理指标的影响。结果表明,在单一Pb(NO_(3))_(2)胁迫下,花生的发芽势、发芽率、胚根长、株高和根长均在大于300 mg/L时显著降低。与单一300 mg/L Pb(NO_(3))_(2)胁迫处理相比,外源添加0.10 mg/L EBR后,花生的发芽势、发芽率、胚根长、株高和根长分别增加28.95%、11.76%、27.96%、6.18%、15.96%,总叶绿素含量增加67.34%,可溶性蛋白、可溶性糖含量分别增加19.48%、13.33%,抗氧化酶SOD、POD活性分别增加51.98%、58.62%,丙二醛、游离脯氨酸含量分别降低1.67%、20.73%,超氧阴离子自由基(O_(2)·^(-))积累量减少。说明施加0.10 mg/L外源EBR对Pb胁迫下花生幼苗具有缓解作用,能降低Pb胁迫对花生幼苗的伤害,提高其抗逆性。

油菜素内酯对盐碱胁迫下菊花幼苗生长及生理特性的影响

以菊花耐盐品种‘绚秋江月’和盐敏感品种‘绚秋尽染’为试材,用NaCl和NaHCO3按1∶1(质量比)配制成100 mmol/L复合盐碱处理液,对园林小菊幼苗进行盐碱胁迫处理,对其叶片喷施不同浓度(0.001、0.010、0.100、1.000 mg/L)外源油菜素内酯(BR),以喷施H2O为对照(CK),研究BR对盐碱胁迫下园林小菊幼苗生长及生理指标的影响。结果表明:与对照相比,在盐碱胁迫下外源喷施0.100 mg/L BR,‘绚秋江月’和‘绚秋尽染’叶片相对含水量分别提高了8.11%、16.95%;SPAD值分别增加了9.55%和13.97%;相对电导率分别下降了27.63%和24.69%;丙二醛(MDA)含量分别下降了41.24%和67.38%;脯氨酸(Pro)含量分别提高了86.49%和69.46%;过氧化氢酶(CAT)活性分别增大了16.25%和18.14%;过氧化物酶(POD)活性分别增大了46.15%和68.38%;超氧化物歧化酶(SOD)活性分别增大了12.36%和16.32%;抗坏血酸过氧化物酶(APX)活性分别增大了76.88%和95.04%。外源喷施0.100 mg/L BR可以更好地促进盐碱胁迫下园林小菊幼苗的生长发育,提高抗氧化酶活性,增强生物膜的稳定性,从而起到缓解盐碱胁迫对菊花幼苗的伤害,且对盐敏感品种‘绚秋尽染’盐碱受害的缓解效果更佳。

芸苔素内酯浓度对干旱胁迫大白菜幼苗生长及生理指标的影响

【目的】探明不同浓度芸苔素内酯对干旱胁迫大白菜幼苗抗旱性的调控作用,为芸苔素内酯在大白菜生产中的应用提供参考。【方法】以大白菜胜丽118为试验材料,苗期喷施不同浓度(0.05 mg/L、0.1 mg/L、0.5 mg/L、1 mg/L)28-表高芸苔素内酯后,选用10%浓度的聚二乙醇-6000溶液模拟干旱胁迫,测定大白菜生长和生理生化指标,分析不同浓度芸苔素内酯处理大白菜幼苗生理活性差异。【结果】随芸苔素内酯浓度升高,大白菜幼苗长势呈先良好后衰败变化;从大白菜幼苗表型看,芸苔素内酯浓度0.05 mg/L、0.1 mg/L处理的耐旱效果最明显。干旱胁迫下叶片POD和CAT活性随芸苔素内酯浓度升高呈先增强后减弱趋势,MDA含量随浓度升高呈先降后升趋势。芸苔素内酯浓度过高大白菜幼苗叶绿素相对含量变低。【结论】喷施适宜浓度的芸苔素内酯可提高干旱胁迫下大白菜幼苗的抗氧化酶活性,有效缓解干旱胁迫造成的损害,适宜的芸苔素内酯浓度为0.05~0.1 mg/L。

植物生长调节剂在大豆中的应用

植物生长调节剂可显著提升大豆产量,对保障国家粮食安全具有重要意义。文章综述大豆中应用的植物生长调节剂类型及常用植物生长调节剂研究现状,展望大豆化控发展前景,旨在为植物生长调节剂在大豆生产中的应用提供理论依据。

油菜素内酯原位检测电化学免疫传感器

[目的/意义]植物激素的调控对于作物生长至关重要。油菜素内酯作为一种重要的植物内源激素,在作物的生长发育、产量提高以及抗逆性增强等方面扮演着举足轻重的角色。传统的油菜素内酯检测方法不仅繁琐耗时,而且难以实现原位、快速检测。为了突破这一技术瓶颈,本研究提出了一种利用丝网印刷(Screen-printed electrode,SPE)电极构建的电化学免疫传感器,旨在实现对油菜素内酯的快速、准确检测。[方法]首先利用电化学工作站电沉积金纳米颗粒(AuNPs)将其固定在SPE电极表面,然后在电极上滴加氯化铜纳米线(CuCl2NWs),氯化铜纳米线不仅可以提高电极的导电性,其中Cu2+还可以作为传感器的氧化还原探针。最后选择Mxene和聚多巴胺纳米复合材料(Mxene@PDA)作为SPE电极的修饰材料,因为Mxene具有表面积大和导电性好的优点,可以进一步放大Cu2+的信号。但Mxene在空气中很容易被氧化而不稳定。聚多巴胺(Polydopamine,PDA)含有大量的邻苯二酚和氨基等基团,通过多巴胺自聚合后包覆在Mxene的表面,切断氧渗透的路径,使Mxene难以被氧化。Mxene@PDA还可以作为偶联剂在电极表面固定更多的抗体,提高整体的生物相容性。[结果和讨论]传感器具有较宽的线性检测范围:0.1μg/ml^(1) mg/ml,检出限低至0.015 pg/ml (S/N=3)。此外,通过SPE电极对小麦内源的油菜素内酯含量进行离体检测和后续的加标实验,计算出其回收率为98.13%-104.74%。在验证该传感器准确性的同时,也展示了其优越的稳定和灵敏性。与其他油菜素内酯的检测方法相比,本研究中开发的免疫传感器有更加出色的分析性能。除此之外,在对小麦叶片的油菜素内酯的原位检测中,传感器也表现出了极佳的实际应用潜力。[结论]本研究首次研制了用于原位检测油菜素内酯的电化学免疫传感器,不仅为原位检测植物叶片中的油菜素内酯提供了良好的电化学平台,同时在精准农业中具有巨大的应用潜力。

低温胁迫下不同外源激素对玉米发芽及幼苗生理特性的影响

【目的】探究外源油菜素内酯(BR)与脱落酸(ABA)对低温胁迫下玉米发芽及幼苗生长与生理特性的影响。【方法】在室内低温10℃条件下,以寒敏感材料沈137、耐寒材料LH82、PHG47和PHG29为试验材料,分别用5种不同质量浓度的外源BR与ABA浸种、培养作为试验处理;25℃蒸馏水作正向对照(CK+)、10℃蒸馏水作负向对照(CK-)。筛选出BR与ABA的最佳缓解质量浓度,利用最佳缓解质量浓度对沈137、LH82、PHG47和PHG29 4个玉米品种种子的萌发、苗期性状和生理特性进行比较。【结果】低温胁迫下,玉米种子的发芽率、胚芽长、胚根长、胚芽鲜质量等显著降低;幼苗的丙二醛、脯氨酸及可溶性糖含量显著升高,抗氧化酶活性显著增强;适当外施BR与ABA处理能有效缓解低温胁迫对玉米生长的抑制程度,沈137玉米萌发期指标、苗期地上部与地下部生物量指标的增加,MDA含量的降低表明0.10 mg/L BR与5 mg/L ABA处理缓解效果最好。【结论】外施0.10 mg/L BR与5mg/L ABA可有效缓解低温胁迫对玉米生长造成的损害。但对4个玉米品种的缓解能力不同,缓解效果由强到弱顺序为:LH82>PHG47>PHG29>沈137。

喷施不同外源物质对三个优质杂交稻产量和品质的影响

为了在水稻生产中合理利用外源物质,缓解优质杂交稻精米率低,种植效益不高,制约优质稻产业发展的瓶颈问题。以油菜素内酯、硒肥和硅肥等及其不同配组为处理,研究叶面喷施对隆两优534、徽两优丝苗和湘早籼45号优质稻产量和品质的影响。结果表明,除Si+Se喷施导致徽两优丝苗减产外,其余不同处理组合均显著增产,其中Se处理增产最多,其次是BR和Si+BR处理。Se处理下,隆两优534增产效果最佳,有效穗最高,为267.0万穗·hm^(-2),穗实粒数最多,为173.4,结实率最高,为86.4%,增产率最高,为9.76%。外观品质和蒸煮品质Se处理均最好,其次是Si和Si+BR处理。3个品种中隆两优534外观品质和蒸煮品质最佳,糙米率最高,为79.8%,整精米率最高,为65.8%,垩白度较低,为0.6%,且透明度最好,为1.0级,碱消值较高,为6.4级,胶稠度较大,为69 mm,直链淀粉含量较低,为13.1%。隆两优534在Se处理下净增收和产出投入比均最高,分别为148.875元·(667 m^(2))^(-1)和15.14,其次为BR处理、Se+BR和Si+BR处理。综合考虑外观品质、蒸煮品质和增收效果,硒肥处理效果最佳,其次是Si+BR处理。本研究发现,喷施外源物质可有效改善优质杂交稻的产量、品质,该方法投入较少,增产效果显著,可有效增加优质杂交稻的种植效益,且便于规模化推广应用,有利于促进水稻产业发展。

Application of brassinolide alleviates cold stress at the booting stage of rice

The objective of the study was to determine the physiological mechanisms of plants in response to brassinolide(BR) alleviating cold water stress on rice. In this study, physiological responses of rice to exogenous BR and cold water submergence were investigated using the chilling-tolerant cultivar Kongyu 131(KY131) and the chilling-sensitive cultivar Kenjiandao 6(KJD6). A total of 2 mg L^-1 BR increased activities of superoxide dismutase(SOD) and peroxidase(POD) and the contents of soluble sugar, soluble protein, and chlorophyll, but decreased the malondialdehyde(MDA) content in KY131 and KJD6 under cold water stress. The observed decreases in SOD and POD activities and MDA content recovered quickly after plants were returned to irrigation with water at temperatures of about 23.0°C in 2014. Additionally, the contents of nitrogen(N), phosphorous(P), and potassium(K) were increased by BR treatment under cold water stress. Exposure to BR also raised the percentage of high effective leaf area and leaf area index at the heading stage. Furthermore, it promoted soluble sugar synthesis, increased the rate of dry matter accumulation, and enhanced the export and translocation rates of the stem-sheath. The yield in KJD6 was significantly(P≤0.01 and P≤0.05) higher than that of the control in 2013 and 2014, respectively. The effect of BR treatment on rice leaf SOD and POD activities, MDA, chlorophyll, P, and stem-sheath K contents were more significant in KJD6 than in KY131. In conclusion, exogenous BR effectively reduced the physiological and metabolic damage in rice due to cold stress at the booting stage, promoted functional recovery in plants that received irrigation with water at a normal temperature following cold stress, and mitigated the effects of cold water stress on yield.The two varieties exhibited differential responses to BR;the weaker cold-resistant variety was more sensitive to BR and displayed stronger responses to exogenous BR.

Protective Roles of Brassinolide on Rice Seedlings under High Temperature Stress

Two indica rice （Oryza sativa L.） materials, Xieqingzao B （sensitive to heat stress） and 082 （tolerant to heat stress） were used to study the role of brassinolide （BR） in protection of rice seedlings from heat stress. Young seedlings were subjected to high temperature （38℃/30℃） and sprayed with 0.005 mg/L of BR. Analysis was conducted on the contents of chlorophyll, protein and malondialdehyde （MDA）, the leakage of electrolyte, the activities of peroxidase （POD） and superoxide dismutase （SOD） and their isozymes expression levels in leaves. Under the high temperature treatment, application of BR significantly increased the contents of chlorophyll and protein, and the activities of POD and SOD, and reduced the content of MDA and the leakage of electrolyte in the leaves of the heat-sensitive material Xieqingzao B, whereas BR had less effect on those of the heat-tolerant material 082 relatively. The BR treatment enhanced the expression of POD isozymes in the leaves of both materials. Under the high temperature stress and BR treatment, the expression of four SOD isozymes reduced in 082, but the expression of two SOD isozymes increased in Xieqingzao B. This suggests that BR plays an important role in protection of rice seedlings from heat stress by enhancing the activities or expression level of protective enzymes in the leaves. The materials with various heat-tolerance might differ in the mechanism of response to heat stress with BR application.

Gibberellins,brassinolide,and ethylene signaling were involved in flower differentiation and development in Nelumbo nucifera

Hormones play important roles in vegetative and reproductive processes;however,the regulatory roles of hormones in Nelumbo nucifera(Lotus)growth and development are unclear.In this study,nine types of endogenous hormones,including gibberellins(GA_1,GA_3,and GA_4),indole-3-acetic acid(IAA),brassinolide(BR),ethylene(ETH),jasmonic acid(JA),abscisic acid(ABA),and zeatin(ZT)were detected in dormant shoot tips,vegetative shoot tips,developing leaf buds,and developing flower buds of lotus.The results indicated that GA,ETH,and BR signaling can promote vegetative and reproductive development of lotus.GA signaling regulates plant height and stimulates flower bud differentiation.GA levels were the highest in the flower buds;exogenous GA3+4 increased plant height by approximately 90%,increased flower quantity by nearly 40%,and advanced flowering by 4 d.Suppressing GA biosynthesis using paclobutrazol decreased plant height and flower quantity by 38%and 87.1%,respectively,and delayed flowering by 15.6 d.ETH signaling has positive regulatory effects on vegetative growth and flower development.The ETH concentration in the developing leaf buds was at least 50%higher than that in other samples.Ethephon spraying led to remarkable increases in plant height and leaf thickness and extended the flowering duration.BR signaling acts as a growth promoter during vegetative and reproductive development in lotus.The highest BR levels were detected in the vegetative shoot tips.External application of28-epihomobrassinolide resulted in growth-promoting phenotypes including longer scapes,thicker leaves,and prolonged flowering.

Foliar Application of Brassinolide Induced Regulation of Grain Yield and Quality,Antioxidant Responses and Aroma in Fragrant Rice

Brassinolide(BR)is a new green plant growth regulator.The present field study was conducted on two fragrant rice cultivars(i.e.,Meixiangzhan-2 and Xiangyaxiangzhan)to study the effects of foliar application of BR on fragrant rice performance.At the heading stage,BR solutions at 0.05,0.15,0.25 and 0.50 mg L-1 were sprayed on fragrant rice at 600 liters per hectare;these treatments were named as BR1,BR2,BR3 and BR4,respectively.The treatment sprayed with distilled water was taken as a control(CK).Compared with CK,the BR2 treatment significantly enhanced the chlorophyll concentration and net photosynthetic rate for Meixiangzhan-2,and Xiangyaxiangzhan.The BR3 and BR4 treatments increased the concentrations of chlorophyll a,chlorophyll b and carotenoid,and also enhanced net photosynthetic rate by 31.91%and 40.43%,respectively.Higher grain yields were recorded in the BR2 treatment than on CK on Meixiangzhan-2,while on Xiangyaxiangzhan,the BR3 and BR4 treatments increased grain yield compared with CK.In relation to CK,higher head rice rates were recorded in the BR2 treatment for Meixiangzhan-2,and in the BR3 and BR4 treatments for Xiangyaxiangzhan.BR treatments(BR2 for Meixiangzhan-2,BR3 and BR4 for Xiangyaxiangzhan)also significantly enhanced the activities of GPX,SOD and CAT by 10.22%to 23.00%,and reduced the malonaldehyde concentration.In addition,we observed that some BR treatments(BR2 for Meixiangzhan-2,BR3 and BR4 for Xiangyaxiangzhan)decreased the grain 2-acetyl-1-pyrroline concentration of fragrant rice.

Effects of Natural Brassinolide on Seed Germination and Hypocotyl Elongation of Beans

Seeds of soybeans and mung beans were soaked into five different concentrations （0, 0.05, 0.10, 0.20, 0.30 mg/L） of natural brassinolide （ NBR ） solution. According to the results, natural brassinolide treatment could improve seed germination rate and hypocotyl-radicle ratio of soybeans and mung beans and promote the growth of sprouts. To be specific, seed germination rate of soybeans reached the highest in 0.05 mg/L natural brassinolide treatment, which was im- proved by 25.0 percentage points compared with the control group, and the sprout length was improved by 4.33 em; 0.30 mg/L natural brassinolide exhibited the most significant promotion effect on seed germination and sprout growth of mung beans, seed germination rate was improved by 18.3 percentage points and sprout length was improved by 7.29 cm; hypocotyl-radiele ratio of soybean and mung bean sprouts reached the highest （2.96, 1.43 ） in 0.05 mg/L natural brassinolide treatment.

Effect of Natural Brassinolide on Germination of Ailanthus altissima Seeds

The germination capacity of Ailanthus altissima seeds improved after the seeds were soaked with different concentrations of natural brassinolide （NBR）. The germination rate and germination energy of the seeds increased by 17.6% and 18.8%, and the mean germination speed （i.e., germination time） of the seeds was shortened by 1.4 d under the optimal concentration （0.4 mg·L^-1） treatment, compared with the control. After hypocotyls of A.altissima were treated with NBR, the elongation of the hypocotyls increased. Among different concentrations of the NBR, 0.4 mg·L^-1 NBR appeared to be the optimal concentration for the elongation of A.altissima hypocotyls.

STUDIES ON STEROIDAL PLANT GROWTH REGULATOR 24. STEREOCONTROLLED CONSTRUCTION OF THE SIDE CHAIN OF BRASSINOLIDE AND HOMOBRASSINOLIDE VIA A TANDEM VICINAL DIALKYLATION OF PYRANONE MOIETY

A stereocontrolled construction of the side chain of brassinclide and homobrassinolide has been achieved via the tandem vicinal dialkylation of the pyranone moiety as a key step.

STUDY ON THE SYNTHESIS OF BRASSINOLIDE AND RELATED COMPOUNDS 15.FORMAL SYNTHESIS OF BRASSINOLIDE VIA STEREOSELECTIVE SULFENATE-SULFOXIDE TRANSFORMATION

A formal synthesis of the natural growth promoting steroid brassinolide is described,which involves construction of side chain by 1,3-sulfoxide-hydroxyl transposition with methylation from(24S)- 22-E-24-sulfoxide 6 and(24R)-22-E-24-sulfoxide 9,respectively to (22S)-23-E-24-methyl compound 4.

Studies on the Model Synthesis of the Brassinolide and Dolicholide Side Chains

A stereoselective synthesis of brassinolide and dolicholide, which involves construction of the side chain enantiomers by a highly stereoselective aldol reaction of aldehyde 5 with the anion of α-silyloxy ketone 6 is described.

Effect and Its Mechanism of Brassinolide-regulated Starch Metabolism in Rice Germination

The study was aimed to explore the effect and mechanism of brassinolide（ BL） regulated starch metabolism in rice endosperm during seed germination.The radicle elongation of rice seeds treated with 1 μmol/L BL was inhibited during germination. The analysis on rice seeds with a GUS-fused promoter showed that BL had different regulatory effects on Wx,SBEI,and AGPS1. The effect of BL treatment on the physicochemical properties of rice starch was further investigated by scanning electron microscopy,Fourier transform infrared spectroscopy,and X-ray diffraction. The results showed that the starch treated with BL maintained better crystallinity and orderly structure,indicating that during the germination process,the degradation of starch in endosperm was slow,which might be one of the reasons for the slow radicle growth in the early stages of seed germination. This study provided important clues for further analysis of the molecular mechanisms underlying BR-regulated rice seed germination.

Brassinolide类物质的合成

对Brassinolide类物质的合成进行了概述 ,并对其构效关系进行了对比以及简单介绍了其在农业生产上的运用。