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21.
升华硫配合杀螨剂防治蜂螨效果的比较研究   总被引:3,自引:1,他引:2  
[目的]比较升华硫配合杀螨剂防治蜂螨效果。[方法]2007~2009年3次于同一个蜂场采用同一种方法对升华硫配合杀螨剂防治蜂螨效果进行了试验。[结果]升华硫配合杀螨剂对于消灭存在蜂脾上及寄生于封盖蛹的蜂螨有明显效果,对于消灭成年工蜂身体上的蜂螨效果不明显。施药后杀灭大蜂螨的效果以第1天最佳,此后逐日减少;杀灭小蜂螨的效果以第2天最佳,此后逐日减少,表明在2~5 d再施治1~2次,可达到理想的防治效果。在小蜂螨大量滋生时,采用升华硫配合杀螨剂有较为理想的防治效果。[结论]该防治技术可为大、小蜂螨严重危害地区的养蜂生产提供服务。  相似文献   
22.
利用甲醛与乙酰丙酮及铵离子反应,将生成的黄色物质与标准系列比较,定量测定甲醛含量,并用碘标准溶液滴定二氧化硫含量,从而对湿米粉中吊白块含量进行检测,效果良好。  相似文献   
23.
硫对大豆叶面积和叶绿素含量的影响   总被引:4,自引:0,他引:4  
采用盆栽方法,设置4个硫素施用水平,研究硫素营养对大豆叶面积和叶片叶绿素含量的影响。结果表明,施硫能增加大豆叶面积,尤其盛花期作用效果,并显著提高开花至鼓粒期叶片叶绿素a、叶绿素b以及总叶绿素的含量,对产量形成有利。  相似文献   
24.
通过盆栽试验,探讨硫磺和ALA(5-氨基乙酰丙酸,分子式为C_5H_9NO_3)配合施用对盐渍化土壤中作物生长发育的影响.结果表明:在中等用量的硫磺(3 g/kg)和ALA处理下,玉米的生长发育明显优于无处理的对照,玉米幼苗株高和干物质量分别比对照提高45.6%和34.2%.硫磺施入盐渍化土壤中后,明显降低了土壤pH值,改善了作物生长的土壤环境;同时土壤的EC(电导率)明显提高,主要是由于SO_4~(2-),Ca~(2+),Mg~(2+)3种离子含量升高所引起,且大部分硫磺并没有在短期内转化成SO_4~(2-),因此在该类盐渍土中科学施加一定量的硫磺更有利于作物的生长发育,且有一定的后效.由此可见,在盐渍化土壤中施用适量硫磺,并对作物辅以施用ALA的化学调控措施,把作物生长环境改善和抗盐性提高相结合,可以达到较好的效果.  相似文献   
25.
硫包衣肥料在生姜生产上的应用研究   总被引:1,自引:0,他引:1  
为探索硫包衣肥料在安丘生姜上的应用效果,进行3个不同施肥量硫包衣肥料与对照含氯复合肥的肥效对比试验。试验结果表明,施用硫包衣肥料后,生长中后期生姜叶色较绿,茎杆粗壮,长势旺,后期衰败晚,干叶尖差,染病轻,不同硫包衣尿素处理的姜苗鲜重比对照多3214.5~9558.0 kg/hm~2。施用硫包衣肥料的3个处理生姜产量比对照多6675.0~10627.5 kg/hm~2,产值比对照高24030.0~38259.0元/hm~2,且与对照差异达显著水平。同时使用硫包衣肥料显著提高了生姜的投入产出比。从产量产值上来看,施用NPK总量与对照相同的硫包衣复合肥处理(处理4)的增产效果最明显;从投入产出比来看,施用20%硫包衣尿素+80%普通尿素处理(处理3)的投入产出比最大。硫包衣肥料在安丘生姜上的应用效果明显,建议今后在生姜生产中加大硫包衣肥料的推广应用范围。  相似文献   
26.
High soil pH and excessive calcium carbonate (CaCO3) in the Everglades Agricultural Area of south Florida reduce the availability of phosphorus and micronutrients to crops. Sulfur (S) amendment is recommended to reduce soil pH and enhance nutrient supply. The study’s objective was to determine the sulfur amendment effectiveness on soil pH and nutrient availability in organic soil as CaCO3 content increases in soil. An experiment of four S rates (0, 90,224, and 448 kg ha?1) and three added CaCO3 (0%, 12.5%, and 50% by volume) in organic soil was established. Sulfur application had limited effects on soil pH reduction as CaCO3 level increased and therefore failed to enhance nutrient availability; however, it increased sulfate concentration in soils, which could be at risk for export from the field. Unexpected increases in manganese concentration with added CaCO3 was associated with reducing conditions due to increased soil bulk density, which changed the soil physical properties.  相似文献   
27.
Selenite is a form of selenium (Se) commonly found in Se-excessive soils. To regulate the Se content in plants in high-Se areas, a potted soil experiment was performed on oilseed rape (Brassica napus L.) to evaluate the effects of varied amounts of sulfur (S) on the biomass, accumulation and distribution of Se in B. napus under the conditions of different amounts of Se in the soil. The results showed that the seedlings of B. napus were more sensitive to Se than the mature plants were. The addition of S significantly alleviated the growth inhibition in seedlings and facilitated the growth of mature plants under higher Se (15 mg kg?1) conditions. S treatment significantly decreased soil pH within the range of 0.22–0.60. An appropriate moderate amount (150 mg kg?1) of S exerted the strongest inhibition on Se concentration and accumulation in B. napus at the seedling stage, but a higher amount (300 mg kg?1) of S led to a more significant decrease in the mature plants under higher Se conditions, with the maximum reduction in various parts of B. napus reaching 51.3–60.9% and 42.5–53.4%, respectively. The application of S only affected the uptake of Se, and not the translocation of Se; the accumulation of Se in B. napus follows the sequence of pod ≈ stem > rapeseed > root, and the distribution ratio is approximately 1.00:0.97:0.69:0.49. Overall, the application of S alleviated the inhibitory effect on growth caused by excessive Se by reducing the Se concentration in B. napus and facilitating its growth, suggesting that S treatment is a suitable and highly cost-effective method to regulate the content of Se in B. napus.  相似文献   
28.
为了探究绿化树木叶片富集大气污染物的差异性,对新乡市 18种道路绿化树木叶片铅、镉、氯和硫的含量进行测定分析。结果表明:绿化树木对大气污染物具有一定的吸收净化能力,并依污染元素和植物的不同具有明显差异;同种园林植物叶片累积4种污染元素的含量不同,总体来说对氯和硫的累积能力大于铅和镉;对铅累积量高的树木有枇杷、榆树和杨树;对镉累积量高的有枇杷、广玉兰、毛泡桐和杨树;对氯累积量高的有卫矛、大叶黄杨、杨树、榆树和臭椿;对硫累积量相对较高的有杨树、卫矛、毛泡桐和珊瑚树。运用隶属函数法对 18种绿化树木叶片污染元素含量进行归类,杨树和枇杷归为第1类,卫矛、大叶黄杨、毛泡桐、广玉兰、榆树和栾树为第2类,银杏、珊瑚树、臭椿、悬铃木、构树、鸡爪槭、海桐、白蜡、国槐和凤尾兰归为第3类。  相似文献   
29.
As single superphosphate availability decreases due to closure of aging manufacturing plants increasing attention is being paid to alternative phosphorus (P) and sulfur (S) sources. This glasshouse study, conducted under non-leaching conditions was undertaken to evaluate the S supplying capacity of gypsum, S bentonite, elemental S (ES) and a range of P containing fertilizers and those where ES was added as a coating or incorporated. The magnitude of crop response in terms of shoot biomass to applied S fertilizer sources followed the order of sulfates > powdered ES > coated/incorporated ES > S/bentonite. These results indicate that fertilizers containing a mixture of sulfate and micronized ES (<75 µm), either incorporated within the granule or coated onto the fertilizer are agronomically effective. The results also suggest that local S coating of finished fertilizers is a feasible alternative to S incorporation undertaken at a central fertilizer plant.  相似文献   
30.
In most soil ecosystems, soil biological activity and associated processes are concentrated in the rhizosphere soil and is influenced by the external application of plant nutrients. The impacts of boron and sulfur on soil biological properties were evaluated in an Aeric Haplaquept (pH 5.7) growing rapeseed (Brassica campestris L.) as a test crop. Application of boron (B) at 2 mg kg?1 in combination with sulfur (S) at 30 mg kg?1 (B2S30) resulted in highest available Boron and sulfur of 0.239 and 15.4 mg kg?1, respectively and registered 62.5% and 71.3% increase over control (B0S0) at 60 days of crop growth compared to individual applications. The microbial populations viz. phosphate solubilizing microorganisms (PSM) and nitrogen fixing bacteria (NFB) were the highest of 52.63 and 85.87 × 105 g?1 soil, respectively, CFU in B2S30 treatment at 60 days and adjudged as the best treatment combination for enhancement of soil biological indices and seed yield.  相似文献   
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