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171.
The fast decay of free radicals makes application of traditional electron paramagnetic resonance (EPR) techniques impractical for detection of irradiated wheats when the storage time is longer than 30 days. In this study, therefore, the effects of irradiation on wheat seeds were investigated by using the EPR spin probe technique. The technique is based on the ability of the spin probes to transfer valuable information related to the changes in the structural characteristics of embryo cell membranes caused by irradiation. As a result of irradiation, the enviroment of the spin probe is modified and this modification can be followed from the recorded spectra. The doses studied were 1.0, 2.5, 10.0, and 20.0 kGy. An aqueous solution of 16-doxyl stearic acid (16-DSA) was used The embryos were detached using a steel needle and kept in 16-DSA solution for 2.5 hr and washed with distilled water. The spectra of the samples were recorded. The detection of irradiated wheats by this technique was possible at doses of ≥2.5 kGy. An important advantage of this approach is that it is applicable even after eight months of storage.  相似文献   
172.
大豆新品种皖宿1019是宿州市农业科学院2009年以郑9805为母本、周02005为父本进行杂交,采用改良系谱法选育而成。该品种2018年、2019年参加安徽省夏大豆区域试验,2年平均产量2574.5kg/hm2,比对照中黄13增产5.78%。2020年生产试验,平均亩产2892.9kg/hm2,比对照中黄13增产8.8%。适宜于安徽淮北地区中等以上肥力地块种植。2021年通过安徽农作物品种审定委员会审定[1][2](编号:皖审豆20210013)。  相似文献   
173.
几种土壤的氟吸附特性研究   总被引:10,自引:4,他引:10  
采用室内试验方法,研究了4种土壤对氟吸附的特性。结果表明:(1)不同土壤对氟的吸附能力差异很大,随着初始浓度的增大,吸附量明显增大,净吸附量、解吸量也增大,表现为黄壤>红壤>紫色土>石灰土;土壤氟的解吸率随初始浓度的增大而增大,不同土壤间大小次序是石灰土>紫色土>红壤>黄壤。(2)土壤吸附氟后的平衡溶液pH值随氟加入浓度的增大而上升,不同土壤间次序是:石灰土>红壤>紫色土>黄壤。(3)拟合结果表明,Langmuir方程能够较好地拟合土壤对氟的吸附等温线。(4)土壤中氧化物是氟的重要吸附剂,对土壤氟吸附有重要贡献。(5)低分子有机酸对氟吸附的影响一方面表现为阴离子的竞争作用,另一方面表现为酸性条件下的促进作用。  相似文献   
174.
The effect of boron phosphate (BPO4) nanoparticles on the mechanical, thermal, and flame retardant properties of polypropylene (PP) and polyamide 6 (PA-6) fibers are investigated by tensile testing, thermogravimetric analysis (TGA), differential scanning calorimeter (DSC), and micro combustion calorimeter (MCC). The addition of BPO4 reduces the mechanical properties of the both PP and PA-6 fibers. According to the TGA results, the addition of BPO4 does not change the thermal behavior of PP fiber and slightly reduces the thermal stability of PA-6 fiber by about 30 °C. According to MCC results, the addition of BPO4 does not change the effective total heat evolution and heat release rate (HRR) peak for PP fibers. Although the inclusion of BPO4 does not change the total heat evolution of PA-6 fiber, it reduces the HRR peaks due to increase in barrier effect of char.  相似文献   
175.
Rhizobium spp. (local isolate) was used to inoculate three bean (Phaseolus vulgaris L.) varieties; Akman 98, G?ynük 98 and Sehirali 90, in a factorial field experiment. The objective of the experiment was to study effect of inoculation on seed yield, protein range, seed weight, non-soaker capacity and hydration index. Rhizobium spp. inoculation and nitrogen fertilizer significantly increased characters tested. This study revealed that inoculation with Rhizobium spp. improved seed quality.  相似文献   
176.
A pot experiment in a greenhouse was conducted in order to investigate the effect of different N2‐fixing, phytohormone‐producing, and P‐solubilizing bacterial species on wheat and spinach growth and enzyme activities. Growth parameters and the activities of four enzymes, glucose‐6‐phosphate dehydrogenase (G6PD; EC 1.1.1.49), 6‐phosphogluconate dehydrogenase (6PGD; EC 1.1.1.44), glutathione reductase (GR; EC 1.8.1.7), and glutathione S‐transferase (GST; EC 2.5.1.18) were determined in the leaves of wheat (Triticum aestivum L., Konya) and spinach (Spinacia oleracea L.), noninoculated and inoculated with nine plant growth–promoting rhizobacteria (PGPR: Bacillus cereus RC18, Bacillus licheniformis RC08, Bacillus megaterium RC07, Bacillus subtilis RC11, Bacillus OSU‐142, Bacillus M‐13, Pseudomonas putida RC06, Paenibacillus polymyxa RC05 and RC14). Among the strains used in the present study, six PGPR exhibited nitrogenase activity and four were efficient in phosphate solubilization; all bacterial strains were efficient in indole acetic acid (IAA) production and significantly increased growth of wheat and spinach. Inoculation with PGPR increased wheat shoot fresh weight by 16.2%–53.8% and spinach shoot fresh weight by 2.2%–53.4% over control. PGPR inoculation gave leaf area increases by 6.0%–47.0% in wheat and 5.3%–49.3% in spinach. Inoculation increased plant height by 2.2%–24.6% and 1.9%–36.8% in wheat and spinach, respectively. A close relationship between plant growth and enzyme activities such as G6PD, 6PGD, GR, and GST was demonstrated. Plant‐growth response was variable and dependent on the inoculant strain, enzyme activity, plant species, and growth parameter evaluated. In particular, the N2‐fixing bacterial strains RC05, RC06, RC14, and OSU‐142 and the P‐solubilizing strains RC07 and RC08 have great potential in being formulated and used as biofertilizers.  相似文献   
177.
农田土壤养分变异与施肥推荐   总被引:29,自引:6,他引:29  
采用差分式GPS定位的方法 ,对山东省青州市王母宫乡王七村 5.47hm2的地块进行了50m50m的网格式取样 ,用土壤系统研究法对其大、中、微量元素进行了分析。结果表明 ,土壤中的营养元素均存在着一定的变异。根据土壤养分的抽样分布 ,可将土壤养分分为两种类型 ,一为偏斜型营养元素 ,主要有氮、磷、硫等 ;其它属另一类 ,为非偏斜营养元素。造成土壤营养元素偏斜的主要原因是施用化学肥料。对施肥较多 ,且施肥历史较长的营养元素 ,在进行测土推荐施肥时 ,不仅要考虑大田的平均养分含量 ,还应考虑土壤的养分的空间变异状况 ;对非偏斜元素的施肥推荐以大田平均值即可  相似文献   
178.
摘要:利用室内试验与池塘试验相结合的方法,研究了不同浓度的EM菌原液对海参养殖水体理化因子的影响效果。结果表明,EM菌对水体的溶解性固体(TDS)、电导率(cond)无显著影响(p>0.05);能显著增加水体氧化还原电位(ORP)、DO、透明度(SD)(p<0.05):其中以Ⅳ组(4*109cfu/m3)效果最好,分别平均增加3.39%(试验箱)和8.38%(试验池)、26.20%(试验箱)和18.58%(试验池)、54.69%(试验池);pH各试验箱间缓慢下降,但差别不显著(p>0.05),试验池比对照池平均下降3.94%,均值为7.79,仍在适宜范围内。 关键词:EM菌; 海参养殖; 水体理化因子  相似文献   
179.
摘要:长江班鳜(Siniperca scherzeri steindachner)的催产和受精卵的孵化受天气、温度、水温影响较大。在不同水温条件下效应时间、受精率明显不同。当水温在20±2℃时,效应时间大约为32小时,受精率大于80%,水温低于18时,效应时间明显延长,受精率也较低;在水温20-24℃时孵化时间大约125小时,孵化率均超过90﹪。班鳜幼苗出膜后大约经过30-56小时候开始开口。幼苗全长(L,mm)与日龄(D,d)的线性关系为L=3.244+0.926D。  相似文献   
180.
采用不同颜色(即不同波长)的光对福寿螺(Ampullaria gigas)进行室内照射试验,分析探讨了不同壳色福寿螺的趋避效应。结果发现,黄壳螺较黑壳螺对光更为敏感,橙色和红色光对黄螺有明显的驱避效应,黄螺对黄色光趋向性最高;红色光对黑螺有明显的驱避效应,黑螺对绿光和蓝光的趋向效应更为明显。研究结果可为利用灯光对稻田福寿螺进行物理防控提供一定的科学依据。  相似文献   
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