Dormancy of Amaranthus retroflexus L. Seeds and Physiological Response Seedlings to Acifluorfen Sodium

Amaranthus retroflexus L. is a serious and widespread malignant weed in soybean fields in Heilongjiang Province. Exploring the dormancy characteristics of A. retroflexus L. seeds and the physiological response of its seedlings to acifluorfen sodium can provide a basis for further researches on its resistance mechanism. Using newly harvested and stored A. retroflexus L. seeds for one year as experimental materials, the effects of different concentrations of HCl, NaOH, water temperature, gibberellic acid(GA) and polyethylene glycol(PEG) on the dormancy and germination of A. retroflexus L. seeds were studied. The sensitivity of A. retroflexus L.to acifluorfen sodium was determined using bioassay. The effects on leaf chlorophyll content and target enzyme activity were studied at a normal dosage of 360 g a.i. hm^(-2) and a doubling dosage of 720 g a.i. hm^(-2) of acifluorfen sodium. Newly harvested seeds exhibiting dormancy were soaked in water of various temperatures and in different concentrations of NaOH and HCl, which were ineffective in breaking the seed dormancy. GA could break seed dormancy, and the highest seed germination rate reached 93.33% when they were soaked at 3 000 mg·L^(-1) for 72 h and 4 000 mg·L^(-1) for 48 h. The drought stress was simulated with a 15%-25% polyethylene glycol solution, which had no significant effect on the seed germination rate. The GR_(50) value of acifluorfen sodium for A. retroflexus L. was 705.7 g a.i. hm^(-2), which was 1.96 times the recommended dose in the field. After the application of different doses of acifluorfen sodium, the chlorophyll content of A. retroflexus L. reached its minimum value 3 days after treatment(DAT), and then gradually increased. The activity of the target enzyme protoporphyrinogen oxidase(PPO) reached the highest value at 7 DAT under different dosages, and gradually returned to normal levels thereafter. Soaking with gibberellin was an effective method to break seed dormancy. A. retroflexus L. seeds had certain drought resistance during the germination process. A. retroflexus L. was not sensitive to acifluorfen sodium and acifluorfen sodium ether, and could not effectively inhibit the PPO activity, indicating that A. retroflexus L. had target resistance to acifluorfen sodium.

Effects of Electroplating Effluents on Growth, Heavy Metals Accumulation and Concentrations in Amaranthus viridis Lin.

Pollution in recent times has become prevalent due to industrial expansion,hence,releasing pollutants into the environ-ment.Thus,this study aimed at investigating the effects of effluents from electroplating companies on growth,heavy metals accumulation and concentrations in Amaranthus viridis.Seeds of A.viridis were obtained from the National Institute of Hor-ticulture,Ibadan.Loam soils were collected from Lagos State University and two samples of electroplating effluents were obtained from Oregun,Lagos.Seeds were sown,nursed,and transplanted in a uniform bucket filled with 5 kg loam soil and transplanted seedlings were treated with Effluent A(5 and 10%conc.)and Effluent B(5 and 10%conc.)and control respec-tively.Growth parameters such as plant height and so on were measured and plant samples harvested were analyzed for heavy metal concentrations using Atomic Absorption Spectrophotometer.Data collected were subjected to a one-way analysis of variance.Results revealed that Effluents A and B are highly acidic and above discharge limits.Also,the result revealed that 5%conc.of Effluents A and B had more effects on growth(p<0.05)of A.viridis across the harvests than 10%conc.in relation to control.This result showed that the effluent samples affect the growth rhythms of plants.Results further revealed vigorous–1–1 accumulation of the heavy metals:Zn(241.66µg kg±0.10 at third harvest in Effluent A:10%),Cu(68.25µg kg±0.23 at–1–1 first harvest in Effluent B:5%),Cr(500µg kg±0.90 in harvests at all concentrations.)and Ni(500µg kg±0.90 at third harvest in Effluent B:5%)and all these metals are far above the control and permissible limits of WHO/FAO recommenda-tions.From this study,it could be concluded that electroplating effluents had adverse effects on growth and increased metals’bioaccumulation in A.viridis.Therefore,the treatment of effluents to enhance an eco-friendly environment should be done.

苋菜LAC基因家族成员全基因组鉴定与表达分析

漆酶作为生物体内一类重要的铜蓝蛋白,起着调控植物生长、抵抗逆境的作用。基于苋菜基因组及转录组数据,对苋菜漆酶基因家族成员(AtrLAC)进行鉴定,利用在线软件进行生物信息学分析,并根据转录组TPM值进行家族成员相对表达分析。结果表明,在苋菜基因组中共筛选获得19个LAC基因;AtrLAC家族蛋白长度范围在118~1191 aa之间,分子量为13.05~135.10 kD;理论等电点范围为6.49~9.85,多数为亲水呈碱性稳定的蛋白;亚细胞定位预测显示多数在细胞膜外或质膜上。系统进化树分析将苋菜19个LAC成员和拟南芥的17个LAC成员聚为6个类群。TPM值分析显示,AtrLACs在不同处理下的表达量存在差异,其中AtrLAC7基因可能在甜菜色素合成、响应激素调控及光条件下发挥重要作用。

Effects of Nitrogen on the Competitiveness of Echinochloa colona and Amaranthus viridis with Direct-seeded Rice

Information on weed competitiveness responses to added nitrogen （N） is required to assist with the development of appropriate fertilizer management strategies where weed competition is anticipated. A greenhouse study was conducted to examine the effects of four N rates on the competitive ability ofEchinochloa colona and Amaranthus viridis grown together with direct-seeded rice. Rice and each weed species were grown in a replacement series design at added N rates of 0, 50, 100, and 150 kg ha1. Replacement series diagrams for relative yield showed that competitive ability ofE. colona increased with added soil N. Values of weed aggressivity index for E. colona also significantly increased with the addition of N in the soil. In the absence of added N, A. viridis was more competitive than rice but this relationship slightly changed as N was added. However, values of weed aggressivity index of were statistically similar at all N rates. The results suggest that the competitiveness ofE. colona increased with added soil N, and A. viridis unchanged by soil N levels. Both weed species were different in their response to higher N levels. Information gained in this study could be used to demonstrate the importance of effective weed and fertilizer management.

Phytochemical Profiling with Antioxidant and Antimicrobial Screening of <i>Amaranthus viridis</i>L. Leaf and Seed Extracts

Methanol extracts of the dried leaves and seeds of Amaranthus viridis were collected and used for phytochemicals and antibacterial analysis. By detecting the MIC and zone inhibition, the antibacterial activity was determined against different bacterial and fungal strains. The extract yields from the leaves and seeds ranged 5.5-6.1 and 2.42%-3.72% w/w, respectively. Phytochemical investigation of this plant determines that tanins (6.07%-5.96%), saponins (53%-32%), alkaloids (13.14% - 11.42%), protiens (16.76%-24.51%) and glycosides (63.2%-32.3%) were rich in leaves. The extracts also contained appreciable levels of total phenolic contents (2.81-3.61 GAE, g/100 g), total flavanoid contents (18.4-5.42 QE, g/100 g) and DPPH free radical scavenging activity, showing IC50 (83.45-75.95 μg/mL) along with reducing power was calculated. The MIC of extracts ranged 178 - 645 μg/mL. The results of this study suggest the possibility of using the methanolic extracts in treating the diseases caused by the test organisms.

Characterization of the antigenic properties of pollen allergen in Amaranthus viridis

To characterize and purify the allergen extracted from Amaranthus viridis pollen.Extracts of Amaranthus viridis pollen was prepared and analyzed by SDS-PAGE.The protein bands were visualized by staining the gel with Coomassis blue and analyzed by immuno-blotting with serum from 30 allergic patients and from 20 normal people.30 protein bands were detected in SDS-PAGE.2 of these bands with molecular weight of 75 kD a and 67 kD a,showed immumo-reactivity with IgE in the sera from patients with allergy to Amaranthus viridis pollen.The 75 kD a and 67 kD a protein was the major allergen.Meamwhile,Ion-exchange chromatography with DE-52 was used for purification of the antigens.The purified products were characterized by Westerm-blotting.Result from the Ion-exchange chromatography indicated that the pollen allergens(75 kD a and 67 kD a)from the Amaranthus viridis pollen were eluted in theⅠandⅡpeak.The study shows pollen extracts from Amaranthus viridis pollen was purified and characterized and the major allergen was 75 kD a and 67 kD a protein.

EDTA和柠檬酸对反枝苋(Amaranthus retroflexus L.)Cu迁移富集影响研究

为明确反枝苋(Amaranthus retroflexus L.)对Cu的富集能力及EDTA与柠檬酸(CA)对Cu迁移的影响,采用盆栽试验,在0、100、200、400、800 mg·kg-1 Cu处理质量分数及2.5 mmol·kg-1 EDTA和柠檬酸施加条件下,测定了根际土、非根际土Cu不同形态含量及反枝苋组织Cu富集特征。结果表明:Cu处理质量分数小于400 mg·kg-1时,重金属Cu组织富集特征为根>叶>茎,Cu处理质量分数在400 mg·kg-1时,富集特征为根>茎>叶,Cu各处理组BCF与TF均小于1,不具备Cu超富集植物特征;EDTA、柠檬酸均可促进反枝苋对土壤中Cu的富集,并强化Cu由根系向地上部分的转移。EDTA的促进作用远高于柠檬酸,在Cu 800 mg·kg-1,施EDTA处理组反枝苋地上部分Cu可达3 513 mg·kg-1。施加EDTA可增加根际土全Cu含量,显著减少根际土中Fe-Mn态Cu含量,增加Exch态,促使Fe-Mn态向Exch态的转化;柠檬酸处理的根际土中则以Fe-Mn态向Carb态转化为主。由此可见,在EDTA强化修复下,反枝苋富集Cu的能力明显增加,而根际土中Cu全量的增加,是Cu-EDTA迁移活性极大增加与反枝苋防御性Cu阻隔共同作用的结果。

山东长岛南4岛狗尾草(Setaira viridis(L.)Beauv)种群遗传多样性的ISSR分析

利用ISSR分子标记技术研究了山东省长岛县南部4岛90份狗尾草材料的遗传多样性及遗传结构.13个ISSR引物共扩增出148个位点,多态性位点比率为70.30%,Shannon信息指数在物种水平上为0.344 9.根据Gst值,遗传变异有16.53%发生在种群间.遗传距离分析表明,NCS种群与DHS种群遗传一致度最高,遗传距离与地理距离之间没有相关性.

Anti-diabetic and anti-cholesterolemic activity of methanol extracts of three species of Amaranthus

Objective:To investigate the anti-diabetic and anti-cholesterolemic activity of methanol extracts of leaves of Amaranthus caudatus,Amaranthus spinosus and Amaranthus viridis in normal and streptozotocin(STZ) induced diabetic rats.Methods:In this study,the anti-diabetic and anti-cholesterolemic activity of methanol extracts of leaves of all three plants was evaluated by using normal and STZ induced diabetic rots at a dose of 200 mg/kg and 400 mg/kg p.o.daily for 21 days.Blood glucose levels and body weight were monitored at specific intervals,and different biochemical parameters,serum cholesterol,serum triglyceride,high density lipoprotein, low density lipoprotein and very low density lipoprotein were also assessed in the experimental animals.Histology of pancreas was performed.Results:It was found that all the three plants at 400 mg/kg dose showed significant anti-diabetic and anti-cholesterolemic activity(P<0.01),while at 200 mg/kg dose less significant anti-diabetic activity(P<0.05) was observed.Concluslons: Methanol extracts of Amaranthus caudatus,Amaranlhus spinosus and Amaranthus viridis showed significant anti-diabetic and anti-cholesterolemic activity,which provides the scientific proof for their traditional claims.

不同积累型苋菜(Amaranthus mangostanus L.)镉吸收转运特征差异性研究

【目的】比较高积累型苋菜品种Tianxingmi与低积累型苋菜品种Zibeixian在Cd胁迫下Cd吸收转运特征差异性,揭示苋菜品种Tianxingmi高积累镉的机理。【方法】采用水培试验,添加代谢抑制剂来研究两品种苋菜根系吸收Cd的主要途径。分别在30μmol/L Cd Cl2处理4 h、8 h、16 h、1 d和2 d采样测定,采用非损伤微测技术(Non-invasive micro-test technique,NMT),进行植物活体动态测试,调查、测量两品种苋菜根系Cd^(2+)离子流特征,比较了两品种对代谢抑制剂的反应。【结果】在30μmol/L Cd Cl2处理1 d后,Tianxingmi生物量达到最大值5.90 g/plant,是Zibeixian生物量的二倍;Tianxingmi根、茎和叶中Cd浓度分别为609、254和62.3mg/kg,分别是Zibeixian的1.4倍、1.9倍和1.6倍,地上部和全株的Cd累积量分别高达602.0、1308μg/plant;Tianxingmi富集系数(BCF)与转运系数(TF)分别为Zibeixian的2.1倍和1.5倍,这些结果两品种均表现出显著性差异(P<0.05)。NMT技术测定两品种根系Cd^(2+)离子流,通过扫描位点测定发现,距根尖0~300μm范围内两品种苋菜根系Cd^(2+)内流最强且差别最大,并在此做定点位点测定,发现Tianxingmi根系Cd^(2+)内流是Zibeixian根系Cd^(2+)内流的3.75倍,说明了两品种的富集特征与NMT结果一致。添加代谢抑制剂处理显著降低了高积累型Tianxingmi各器官中的Cd浓度,富集系数(BCF)与转运系数(TF),以及根系Cd^(2+)内流(P<0.05),主动吸收特征明显,而对低积累型Zibeixian的相关生理指标影响不大。【结论】两苋菜品种Cd吸收转运特征均表现出显著性差异。Tianxingmi具有更强的Cd吸收和向地上部转运与累积能力,并且根系对Cd的吸收与转运是主动需能的过程,共质体途径在Cd进入Tianxingmi根系并向地上部运输的过程中起着主要作用。

An ABAGE-Like Metabolite of Botrytis cinerea Isolate BC4 Inhibited the Growth of Hypocotyls and Roots of Amaranthus retroflexus Seedlings

A metabolite, which had an inhibitory effect on plant growth, was isolated from cultural filtrate of Botrytis cinerea isolate BC4 by column chromatography on silica gel and preparative HPLC. Its structure was determined from HPLC-ESI MS, GC, IR, ^1H NMR and ^13C NMR spectral data, as well as chemical hydrolysis. The results showed that this metabolite was quite similar to abscisic acid-β-D-glucopyranosyl ester（ABAGE） in structure. The inhibitory effect of the ABAGE-like metabolite on plant growth was investigated using a weed Amaranthus retroflexus L. as a bioassay material. The results showed that it inhibited hypocotyls and roots growth of A. retroflexus （Amaranthus retroflexus L.） seedlings when its concentration was over 0.5 μM. The concentrations for 50% inhibition of hypocotyls and roots growth of A. retroflexus seedlings were 2.8 and 1.4 μM, respectively.

Extraction and Purification Process Optimization and Antioxidant Activity in vitro of Flavonoids in Amaranthus caudatus L.

[Objectives]To explore the optimal extraction and purification process of the flavonoids in Amaranthus caudatus L.and to study the antioxidant activity in vitro of the flavonoids in A.caudatus.[Methods]Taking A.caudatus as the raw material,flavonoids were extracted by alcohol extraction method,and AB-8 macroporous adsorption resin was selected for purification.The hydroxyl radical scavenging ability,DPPH radical scavenging ability,and O^2-radical scavenging ability were used as evaluation indicators,to explore the antioxidant activity in vitro of the flavonoids in A.caudatus.[Results]The optimal extraction process conditions of flavonoids in A.caudatus are:liquid-to-material ratio 40:1,extraction temperature 60℃,ethanol concentration 60%,ultrasonic power 320 W,extraction time 50 min.Under these conditions,the extraction yield of flavonoids in A.caudatus is(1.35±0.01)%.The optimal purification process conditions of flavonoids in A.caudatus are 2.5 g AB-8 macroporous adsorption resin,sample volume 5 mL,mass concentration of adsorption solution 1.60 mg/mL,pH value of adsorption solution 3.0,sample flow rate 3 BV/h,ethanol concentration in desorption process is 70%and the desorption flow rate is 3 BV/h.Under these conditions,the recovery rate reaches 88.35%±0.68%.[Conclusions]A.caudatus has a high content of flavonoids and has excellent free radical scavenging ability in vitro.This study is intended to provide important technical support for the research of flavonoid activity of A.caudatus and the development of functional products.

Essential Oils from Mentha viridis(L).L.and Mentha pulegium L.:Cytogenotoxic Effects on Human Cells

The essential oils from Mentha viridis (L). L. and Mentha pulegium L. were studied to assess their inhibitory potential on phospholipase from snake venoms and to determine their cytogenotoxic action on human cells. These essential oils were able to inhibit the breakdown of phospholipids induced by venoms of snakes of the Bothrops genus. Both oils presented hemolytic activity, although the Mentha viridis (L). L. oil induced hemolysis only at the highest concentrations (14.6 and 29 μL&#183mL-1). The essential oil from M. viridis induced 3.9;8.6 and 16.2 times greater damage to human leukocyte DNA than that observed with the positive control (100 μg&#183μL-1 doxorubicin) at concentrations of 0.25;0.5 and 1.0 μL&#183mL-1, respectively. A similar effect was observed for the oil from M. pulegium (2.1, 2.5 and 15.8 times greater damage). The results extend the characterization of these essential oils and demonstrate their potential use in industries.

反枝苋对氟磺胺草醚的抗性机制代谢组学研究

二苯醚类除草剂氟磺胺草醚是防除大豆田杂草反枝苋Amaranthus retroflexus L.的主要除草剂,但黑龙江省大豆田反枝苋对氟磺胺草醚的抗性越来越强,严重影响大豆产量。目前尚无关于反枝苋对氟磺胺草醚抗性机制的代谢组学研究。本研究基于未处理(CK)以及氟磺胺草醚处理后反枝苋敏感种群(SY)、抗性种群(RY)的叶组织的代谢谱,进行主成分分析(PCA)和正交偏最小二乘法判别分析(OPLS-DA),发现RY组代谢分子表型更贴近于CK组。京都基因与基因组百科全书(KEGG)富集分析和拓扑分析结果发现,氟磺胺草醚的主要作用通路有3条,分别是biosynthesis of amino acids (氨基酸的生物合成)、arginine biosynthesis (精氨酸生物合成)和2-oxocarboxylic acid metabolism (2-氧代羧酸代谢)。CK vs RY和SY vs RY有1条共有的差异通路——degradation of flavonoids (类黄酮的降解),因此,类黄酮的降解可能是RY组抗性的特异性通路。通过支持向量机(SVM)分析进一步发现,4-hydroxy-2-oxoglutaric acid (4-羟基2-氧化戊二酸)、citrulline (瓜氨酸)和L-ornithine (L-鸟氨酸)是氟磺胺草醚处理后反枝苋产生抗药性的关键代谢物。

反枝苋对氟磺胺草醚的抗性水平及分子机制

[目的]本研究旨在明确黑龙江省大豆田反枝苋(Amaranthus retroflexus L.)种群对氟磺胺草醚的抗药性水平,并研究其产生抗性及多抗性的分子机制。[方法]利用琼脂法快速测定采自黑龙江省嫩江县的3个反枝苋种群对氟磺胺草醚的抗性水平。通过盆栽法筛选出抗氟磺胺草醚/噻吩磺隆的反枝苋植株,并进行原卟啉原氧化酶(protoporphyrinogen Ⅸ oxidase, PPO)和乙酰乳酸合酶(acetolactate synthase, ALS)的靶标基因测序。[结果]相比于敏感种群,黑龙江省3个种群对氟磺胺草醚的相对抗性倍数(resistance index, RI)分别为83.6、83.8和93.4;位于反枝苋PPO2高度保守区域编码128位氨基酸的核苷酸由AGG突变为GGG,导致精氨酸被替换为甘氨酸(Arg-128-Gly)。3个抗氟磺胺草醚的反枝苋种群均对ALS抑制剂类除草剂产生多抗性。对als基因测序后发现,与敏感种群相比,各抗性种群10个单株的ALS保守区域均发生多个不同位点(Ala-205-Val、Asp-376-Glu、Trp-574-Leu和Ser-653-Thr)及组合的氨基酸取代方式,各种群突变位点和杂合度多样。[结论]PPO2的Arg-128-Gly氨基酸取代可能是黑龙江3个反枝苋种群对氟磺胺草醚产生抗性的主要原因,3个种群同时对ALS抑制剂类除草剂存在靶标位点突变导致的多抗性。

柱前衍生RP-HPLC法测定狗尾草种子氨基酸含量

【目的】采用柱前衍生反相高效液相色谱（RP—HPLC）法检测狗尾草种子中游离氨基酸和水解氨基酸含量，为阐明其应用价值提供支撑。[方法】制备狗尾草种子的水解氨基酸样品溶液和游离氨基酸样品溶液，以异硫氰酸苯酯和三乙胺进行柱前衍生，建立RP—HPLC法，检测方法的精密性、稳定性、重复性。利用RP—HPLC法，采用梯度洗脱方法，检测狗尾草种子中游离氨基酸和水解氨基酸含量。【结果】21种氨基酸的检测浓度线性范围为0．0019～2．7000#mol／mL，相关系数R2均≥0．9990。21种游离氨基酸的平均加样回收率在87．50％～100．20％，相对标准偏差（RSD）在0．82％～2．46％；水解氨基酸的平均加样回收率在91．10％～100．21％，RSD在0．52％～2．08％。必需氨基酸和半必需氨基酸在狗尾草21种游离氨基酸和水解氨基酸中均含有，但水解后色氨酸、天冬酰胺、组胺酰胺遭到了破坏，含量较低。【结论】建立的氨基酸测定方法稳定、快速、精密度高、线性范围宽，适合狗尾草种子中游离氨基酸和水解氨基酸的含量测定。狗尾草种子中含有丰富的游离和水解氨基酸。

基于DNA条形码鉴别青葙子及其混伪品绿穗苋种子

目的:基于DNA条形码对青葙子、绿穗苋种子进行鉴定。方法:基于ITS2、psbA-trnH、matK、rbcL常用DNA条形码的通用引物对样品进行扩增、测序,并从NCBI数据库下载ITS2、psbA-trnH、matK、rbcL碱基序列。利用MEGA 11.0软件构建NJ系统发育树、计算遗传距离及比较种间差异,并基于ITS2序列构建二级结构。结果:基于上述序列构建的NJ树均独立聚为一支,其中ITS2的种间遗传距离最大,基于ITS2构建的二级结构具有明显差异。结论:基于DNA条形码ITS2碱基序列及其二级结构可准确鉴别出青葙子及其混伪品绿穗苋种子,psbA-trnH碱基序列可以作为辅助鉴别序列。

Antifeedant Activity of Three Plant Extracts Including P. acinosa against Pieris rapae

[Objective] The research aimed to study antifeedant activity of Phytolacca acinosa Roxb., Setaria viridis （L.） Beauv and Viola yedoensis Makino extracts against Pieris rapae. [Method] Activity material was extracted from S. viridis （L.）, P. acinosa and V. yedoensis using acetone cold soak method, and non-selective antifeedant activity of extracts to Pieris rapae larva was determined by using lobular plate addition method. [Result] The results showed that the acetone leaching agent of P. acinosa had most obvious antifeedant effects on Pieris rapae. The antifeedant rate were 74.53% and 82.34% at 24 and 48 h respectively. With the concentration increasing, the antifeedant effect of P. acinosa extracts increased. The antifeedant rate of 0.050 g/ml treatment was the highest, being 74.53% and 82.34% at 24 and 48 h. [Conclusion] P. acinosa could be studied and utilized as potential botanical insecticide.

硒和丛枝菌根真菌处理对苋菜生长及硒积累的影响

【目的】探明丛枝菌根真菌(Arbuscular mycorrhizal fungi,AMF)在苋菜富硒栽培中的生物效应,综合评价AMF对不同硒形态处理下苋菜生长和硒积累的影响。【方法】采用盆栽试验,分析了土施外源硒和接种AMF对苋菜光合作用、生长状况、苋菜红素以及硒积累的影响。【结果】硒酸钠、亚硒酸钠和L-硒代半胱氨酸处理均降低了苋菜红素含量,但对菌根侵染率和菌根依赖性均无显著影响,同时显著提高了苋菜叶片叶绿素a、b含量、蒸腾速率(T_(r))、气孔导度(G_(s))、净光合速率(P_n)和胞间CO_(2)浓度(C_(i)),其中L-硒代半胱氨酸处理效果最佳,说明外源硒处理对苋菜的生长有一定的正效应。另外,接种AMF对不同硒处理下苋菜的生长也有促进作用,且提高了叶片苋菜红素含量,同时增强了光合能力和根茎叶硒含量的积累。【结论】接种AMF和外源硒处理均能提高苋菜的光合能力和硒积累能力,从而促进苋菜生长和提高苋菜营养品质,两者交互处理可作为提高蔬菜富硒栽培的有效措施。

不同除草配方对大豆田抗性反枝苋防除效果的研究

为探索黑龙江省北部大豆主产区抗性反枝苋最佳防治方法,文章优选4种苗前封闭除草剂及4种苗后茎叶除草剂进行田间防效试验,分析不同药剂组合对反枝苋的防除效果。结果表明,苗前封闭处理,90%乙草胺EC 1800 g a.i./hm^(2)和30%丙炔氟草胺SC 51 g a.i./hm^(2)对反枝苋防效较高,施药45 d后,反枝苋防效为87.79%;苗后茎叶处理,250 g/L氟磺胺草醚AS(科坦见露灵)750 g a.i./hm^(2)+助剂(伴豆一生)2000 m L/hm^(2)对反枝苋的防效较高,且持效期长;苗前封闭结合苗后茎叶处理,90%乙草胺EC 1800 g a.i./hm^(2)+30%丙炔氟草胺SC 51 g a.i./hm^(2)+250 g/L氟磺胺草醚AS 500 g a.i./hm^(2)+480 g/L灭草松AS 1680 g a.i./hm^(2)+助剂(迪增)225 m L/hm^(2)对反枝苋的防效达93%,且持效期长。大豆田抗性反枝苋防控方法中,苗前封闭处理防效显著高于苗后茎叶处理。生产中建议以苗前封闭除草为主,结合苗后化学除草、轮作等措施综合防治反枝苋。