Cuticular uptake of xenobiotics into living plants. Part 2: influence of the xenobiotic dose on the uptake of bentazone, epoxiconazole and pyraclostrobin, applied in the presence of various surfactants, into Chenopodium album, Sinapis alba and Triticum aestivum leaves     

Forster WA  Zabkiewicz JA  Liu Z 《Pest management science》2006,62(7):664-672

This study has determined the uptake of three pesticides, applied as commercial or model formulations in the presence of a wide range of surfactants, into the leaves of three plant species (bentazone into Chenopodium album L. and Sinapis alba L., epoxiconazole and pyraclostrobin into Triticum aestivum L.). The results have confirmed previous findings that the initial dose (nmol mm(-2)) of xenobiotic applied to plant foliage is a strong, positive determinant of uptake. This held true for all the pesticide formulations studied, although surfactant concentration was found to have an effect. The lower surfactant concentrations studied showed an inferior relationship between the amount of xenobiotic applied and uptake. High molecular mass surfactants also produced much lower uptake than expected from the dose uptake equations in specific situations.  相似文献   

Preliminary Research on Seed Production and Nutrient Content for Certain Quinoa Varieties in a Saline–Sodic Soil     

Th. Karyotis  C. Iliadis  Ch. Noulas  Th. Mitsibonas 《Journal of Agronomy and Crop Science》2003,189(6):402-408

The aim of the present study was to compare the potential seed yield of eight quinoa varieties, to explore their mineral composition of seeds and to identify superior varieties in two locations with different soil properties. Compared with neutral soil conditions, seed yield in the marginal (saline–sodic) soil was decreased by 45 %. Under the latter soil conditions seed yield was negatively correlated with crop density, indicating that a considerable yield loss was due to poor and uneven plant density caused by adverse soil properties. Among the varieties, ‘RU–5–PQCIP–DANIDA–UNA’ produced the highest seed yield (>20 dt ha^?1) when grown under neutral soil conditions. Under marginal conditions, the above‐mentioned variety and ‘N 407’ produced seed yields up to 10 dt ha^?1 whereas the rest reached yields of only about 5 dt ha^?1. The majority of the varieties accumulated significantly more protein (20 %) in the seeds under saline–sodic soil conditions (lower yielding environment). The varieties originated from South America were superior in accumulating protein in the seeds at both locations. Mineral contents of calcium (Ca), magnesium (Mg), zinc (Zn) and manganese (Mn) in the seeds were significantly higher in the neutral soil. No differences were found for phosphorous (P), iron (Fe), copper (Cu) and boron (B) between the two locations. The South American varieties were again superior in mineral composition. Adaptation of certain quinoa varieties even under marginal environments seems promising for seed production and/or protein and mineral content in the seeds. Agronomic data are needed in a due course, over a higher number of locations and/or various climatic conditions.  相似文献   

干旱胁迫对藜麦幼苗生长和叶绿素 荧光特性的影响     

刘文瑜  杨发荣  黄杰  魏玉明  李健荣 《干旱地区农业研究》2019,37(4):171-177

以甘肃省农业科学院自育品种陇藜1号（L-1）、2号（L-2）、3号（L-3）和4号（L-4）及外引品种白藜（BL）幼苗为试验材料，采用盆栽人工控水法，共设置轻度干旱胁迫（LD，土壤含水量为田间持水量的50%~60%）、中度干旱胁迫（MD，土壤含水量为田间持水量的30%~40%）和重度干旱胁迫（SD，土壤含水量为田间持水量的10%~20%）3个水分梯度，以正常浇水为对照（CK，土壤含水量为田间持水量的70%~80%），干旱胁迫15 d后，通过测定幼苗株高、根长、生物量及叶片叶绿素含量、初始荧光（Fo）、最大荧光（Fm）、PSⅡ最大光化学效率（Fv/Fm）、PSⅡ潜在活性（Fv/Fo）及非光化学猝灭系数（NPQ），研究干旱胁迫对藜麦幼苗生长和叶绿素荧光特性的影响。结果表明：（1）随干旱胁迫程度的加剧，参试藜麦品种幼苗株高、地上部分鲜重和地上部分干重呈逐渐降低的变化趋势，SD处理下，各供试品种株高分别降低了30.64%、28.36%、32.67%、37.88%和38.09%，地上部分鲜重分别下降了63.60%、6073%、59.74%、55.92%和61.74%，地上部分干重分别下降了62.96%、52.63%、29.41%、35.71%和60.00%；（2）5个藜麦品种幼苗叶片叶绿素a、叶绿素b、总叶绿素及叶绿素a/b随着干旱胁迫程度的加剧而呈现先升高后降低的趋势,SD处理下，品种L-2、L-3和L-4叶绿素a分别比CK降低了28.48%、33.66%和17.99%,叶绿素b分别比CK降低了47.80%、45.08%和13.90%，总叶绿素含量分别比CK降低了33.22%、36.20%和15.99%;（3）随干旱胁迫程度的加剧，各供试藜麦品种Fo、Fm、Fv/Fm和Fv/Fo均呈下降趋势，SD处理下，各供试品种Fo分别较CK下降了30.61%、14.56%、31.28%、24.39%、24.16%，Fm下降了19.11%、16.56%、16.76%、17.67%、22.19%，Fv/Fm分别下降了5.73%、4.29%、7.81%、4.58%和3.85%，Fv/Fo分别下降了19.40%、14.93%、24.02%、11.34%和12.11%;（4）5个供试品种叶片NPQ随干旱胁迫程度的加剧呈升高趋势，SD处理下，各供试品种NPQ较CK升高了74.79%、161.54%、104.55%、200.00%和196.00%。综上所述说明中度和重度干旱胁迫下，植物细胞失水，叶绿体遭到破坏，光合作用降低，叶绿素合成受到抑制，光合产物减少，从而抑制幼苗生长，地上部分生物量下降。在幼苗生长和叶绿素荧光特性等方面，藜麦品种L-2表现优于其他品种，表明其在干旱胁迫下较其他供试品种具有更强的适应能力。  相似文献