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1.
2002年调查表明,黔东南州烟叶调拨站烟叶仓储库区危害烟叶的主要害虫种类有烟草粉螟和烟草甲2种。选用几种杀虫剂对其进行防治效果比较试验,结果表明:强敌-312WP 50 g 80%敌敌畏EC 250 mL处理区防治效果最好,药后7 d,防治效果达93.56%~96.79%,平均为95.18%;药后15 d,防治效果达90.67%~92.82%,平均为91.75%;药后30 d,防治效果达88.20%~89.53%,平均为88.87%,均显著高于其它4个处理区的防治效果。强敌-312WP 50 g 80%敌敌畏EC 250 mL在大面积防治示范区对2种害虫的防治效果,在仓储烟叶区,空仓地面和包装麻片上的防治效果相近,药后7 d,防治效果在89.66%~93.75%,平均为91.29%;药后30 d,防治效果达92.5%~100%,平均为95.19%;药后90 d,防治效果仍保持在75.00%~86.67%,平均为81.03%。试验示范证明,强敌-312WP 50 g 80%敌敌畏EC 250 mL是防治危害仓储烟叶烟草粉螟和烟草甲的最有效药剂和浓度。该药剂符合高效、低毒、低残留,对人畜安全的现代农药要求,在储烟库区有较好的推广前景。 相似文献
2.
Increasing plant density is an effective and important way to reduce maize yield gaps in Northeast China. However, the fact is that a significant plant density gap exists between optimum plant density and actual plant density in farmers' fields.To quantify the density gap between planned planting density and final harvest plant density(HPD), we studied 60 farmers' fields on three types of soil for three crop seasons from 2015 to 2017 by measuring their plant-plant distance, actual seedlings density(ASD), final HPD and yield. We also explored the potential causes of density loss by digging the places where the seedlings were missing for two consecutive years in 2016–2017. Results show that the three-year average HPD in farmers' fields was 59 699 plants ha~(–1), which was significantly lower than the planned density, including both the machine setting density(MSD; 67 962 plants ha~(–1)) and theoretical plant density(TPD; 67 467 plants ha~(–1)). No significant difference was found in HPD between years and soil types. However, for MSD and TPD, the average value in 2015 was significantly higher than that in 2016 and 2017. No significant difference between soil types was observed. Furthermore,the results from 2016 till 2017 indicated that a lack of seeds in the soil, a failure to germinate due to low-quality seeds,and a lack of seedlings breaking out of the soil due to environmental problems explained approximately 60.88, 10.33 and 28.80% of density loss, respectively. According to our survey, 63% of farmers did not know their own TPD and HPD, and 54% of farmers did not know the density loss. Therefore, we argue that farmers' limited knowledge of density and density loss is an urgent problem that needs to be solved in maize production. These observations will be useful for determining best management practices for maize production and for providing helpful suggestions for machine improvement. 相似文献
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Pei-pei ZHANG Takele Weldu Gebrewahid Yue ZHOU Qing-luo LI Zai-feng LI Da-qun LIU 《农业科学学报》2019,18(5):1014-1023
Wheat leaf rust,caused by Puccinia triticina(Pt),is an important foliar disease that has an important influence on wheat yield.The most economic,safe and effective way to control the disease is growing resistant cultivars.In the present study,a total of 46 wheat landraces and 34 wheat lines with known Lr(leaf rust resistance)genes were inoculated with 16Pt pathotypes for postulating seedling resistance gene(s)in the greenhouse.These cultivars and five wheat differential lines with adult plant resistance(APR)genes(Lr12,Lr22b,Lr34,Lr35 and Lr37)were also evaluated for identification of slow rusting resistance in the field trials in Baoding,Hebei Province of China in the 2014–2015 and 2015–2016 cropping seasons.Furthermore,10 functional molecular markers closely linked to 10 known Lr genes were used to detect all the wheat genotypes.Results showed that most of the landraces were susceptible to most of the Pt pathotypes at seedling stage.Nonetheless,Lr1 was detected only in Hongtangliangmai.The field experimental test of the two environments showed that 38 landraces showed slow rusting resistance.Seven cultivars possessed Lr34 but none of the landraces contained Lr37 and Lr46.Lr genes namely,Lr9,Lr19,Lr24,Lr28,Lr29,Lr47,Lr51 and Lr53 were effective at the whole plant stage.Lr18,Lr36 and Lr45 had lost resistance to part of pathotypes at the seedling stage but showed high resistance at the adult plant stage.Lr34 as a slowing rusting gene showed good resistance in the field.Four race-specific APR genes Lr12,Lr13,Lr35 and Lr37 conferred good resistance in the field experiments.Seven race-specific genes,Lr2b,Lr2c,Lr11,Lr16,Lr26,Lr33 and LrB had lost resistance.The 38 landraces showed slow rusting resistance to wheat leaf rust can be used as resistance resources for wheat resistance breeding in China. 相似文献
4.
水肥耦合对辽西北沙地胡枝子苗木生物量的影响 总被引：1，自引：1，他引：1
采用312-D最优饱和设计,在辽西北典型的半干旱沙地地区开展了水肥耦合试验,研究了不同水肥处理对章古台地区1年生胡枝子幼苗生物量的影响,建立了胡枝子生物量的水肥回归数学模型.结果表明:不同水肥耦合对胡枝子生物量有显著影响,生物量最高值(43.47 g)出现在高水中氮次低磷组合,即土壤含水率17.52%,施氮量266.8... 相似文献
5.
公路作为一种特殊的土地利用类型,对其周边景观格局起着“通道-障碍”双重作用。在RS和GIS技术支持下,以甘肃酒泉-嘉峪关市1986、1996、2006年和2010年Landsat TM/ETM+影像为数据源,应用景观格局指数分析法,对比分析近25 a来,酒泉-嘉峪关段国道312公路两侧不同缓冲区内景观格局变化。结果表明：① 1986-2010年,公路沿线景观格局变化显著,建设用地增加迅速,未利用地明显减少,且主要转化为建设用地;公路辐射作用在不同缓冲区内影响程度存在差异。② G312线酒泉-嘉峪关段交通道路廊道结构特征变化突出,公路连通度和通道作用不断加强。③ 公路及相关设施建设使得沿线景观斑块密度增加,景观异质性增强,部分斑块类型在不同缓冲区表现出一定程度的聚集效应;公路沿线景观格局趋于破碎化、多样化和均匀化。④ 公路沿线以2 000 m内缓冲区影响最大,而公路起始两端的市中心地带影响范围超过3 000 m。两城市扩张与经济发展以及原有景观格局特征是导致公路沿线生态效应差异明显的重要原因。 相似文献
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Renata Matraszek 《Journal of plant nutrition》2015,38(8):1158-1195
The effect of ion exchange substrate Biona-312 addition (2 or 5%) on the macronutrients composition of butterhead lettuce cv. ‘Justyna’ plants under conditions of basic (1.5-times) and intensive (3-times concentrated Hoagland solution) mineral nutrition level was investigated. Both experimental doses of Biona-312 introduced into 1.5-times concentrated Hoagland nutrient solution [electrical conductivity (EC) 2.41–2.47 dS m?1] dropped nitrogen (N) content in roots. Simultaneously statistically proven increase in foliar concentration of total sulfur (S) as well as a decrease in phosphorus (P) and potassium (K) contents in lettuce above- and underground organs were observed. The changes in calcium (Ca) and magnesium (Mg) content were insignificant. Ion exchange substrate supplementation into 3-times concentrated Hoagland nutrient solution (EC 6.85–7.30 dS m?1), significantly elevated N and K contents in above- and underground organs, raised the foliar S content, decreased Ca and Mg contents in leaves, as well as dropped P concentration in roots and increased content in leaves. 相似文献
8.
拮抗细菌GF-312的复合诱变选育 总被引：1，自引：1，他引：0
为了提高已筛选出的拮抗菌株的抑菌活性,以荧光假单胞菌(Pseadomonas fluorescens)GF-312为出发菌株,采用紫外线和微波方法对其进行复合诱变,通过对致死率、正突变率和抑菌活性的测定,确定紫外线和微波诱变的最适时间,结合对诱变菌株的传代稳定性测定,获得高效菌株GF-16,其发酵液的抑菌圈直径达到30.4 mm,抗菌活性比紫外诱变之前（自然选育之后）的菌株GF-51提高了18.8%。 相似文献
9.
沙漠绿洲灌区甜瓜氮磷钾用量优化模式研究 总被引：9，自引：0，他引：9
【目的】为优质甜瓜生产提供科学施肥依据,以挖掘产量潜能,降低生产成本,防止过量施肥造成的环境污染。【方法】连续两年田间试验按氮、磷、钾3因子5水平312-D饱和最优设计方法进行,建立以甜瓜收获后产量、可溶性固形物含量（SSC）和经济效益为目标的肥料效应方程,解析肥料的独立效应与交互效应,确定甜瓜氮磷钾施用量阈值。【结果】相对于不施肥处理（N0P0K0）,施肥后甜瓜产量提高了16.42%-65.98%,SSC提高了6.71（2012年）和6.62（2013年）个百分点;在其他两个施肥因子一致时,施氮量由0增加到360 kg·hm-2,产量分别提高31.23%（2012年）和31.47%（2013年）,SSC增加2.89（2012年）和2.46（2013年）个百分点;施磷量由0增加到180 kg·hm-2,产量提高5.77%（2012年）和7.53%（2013年）,SSC提高0.55（2012年）和1.09（2013年）个百分点;施钾量由0增加到90 kg·hm-2时,产量提高5.51%（2012年）和5.09%（2013年）,SSC提高1.37（2012年）和1.69（2013年）个百分点。甜瓜产量、SSC和经济效益随着氮、磷、钾用量的增加而先增加、后降低。对甜瓜产量、SSC和经济效益影响顺序为氮＞钾＞磷。氮磷、氮钾互作对产量、SSC和经济效益影响较为明显,而磷钾互作的影响均不显著;氮磷互作对产量和经济效益为正效应,对SSC不显著;氮钾互作对产量和经济效益为负效应;磷、钾肥含量较低时,增施氮肥对产量、SSC形成抑制作用,较高时氮肥有明显的增效作用。【结论】综合考虑氮磷钾肥对产量、品质和经济效益的影响,绿洲灌区大田甜瓜高产优质高效益的施肥方案为：施氮量260.22-263.64 kg·hm-2,施磷量133.03-134.08 kg·hm-2,施钾量87.53-88.52 kg·hm-2,产量为44 356 kg·hm-2,SSC 13.61 %,经济效益68 445 yuan/hm2。 相似文献
10.
高效液相色谱法测定FQS-110的含量 总被引：1，自引：0，他引：1
用Ｉｒｒｅｇｕｌａｒ－Ｈ Ｃ１８色谱柱,以０．０５ｍｏｌ／ｌ柠檬酸溶液（以三乙胺调ｐＨ４．０）：乙腈（８１：１９,ｖ／ｖ）为流动相,以邻氨基苯甲酸为内标,于２７３ｎｍ波长处,测定ＦＱＳ－１１０含量,药物浓度（ｘ）与药物峰面积和内标峰面积之比（ｙ）呈良好的线性关系,线性方程为ｙ＝０．０８７５ｘ－０．０９３３,ｒ＝０．９９９４,线性范围为４￣４０μｇ／ｍｌ,日内与日间变异系数分别为０．６４％和０．６７ 相似文献