我国农业对外贸易与投资合作的关联机制研究

我国在大力发展农业的同时，还在进行对外贸易与投资合作，针对九四年到零七年间我国对 外经济贸易往来的数据，可以推断出，我国农业对外贸易与投资合作之间存在一定的关联性，而且是 相互作用、相互影响的，本文将采用几种分析方式，来对外商对华农业的投资带来的农业贸易方面的 影响和作用进行探讨，下文将借助图表来对关联机制进行研究。     

汉阴县2018-2019年油菜直播品种对比试验初报

摘要:综合所有试验品种的生育性状及产量结果进行比较，该实验表明，6个参试品种产量结果由高到低依次为：中油杂24、陕油28、中油杂19、大地199，汉油1618，秦优28，但在处理间及重复间产量差异均不显著。6个品种直播后生育期均适宜我县栽培。但大地199，中油杂19，中油杂24等三个品种丰产性、抗病性较好，且抽薹早，可采摘食用，下一步应继续开展实验，探索三个品种适宜播期、采薹期，并对采薹的产量结果及菜薹经济收益进行综合分析，为陕南优质油菜综合利用技术积累科学数据。     

压捆机压缩频率与压缩室三维应力关系的试验研究

压缩频率与压缩室三维应力直接影响牧草压捆机的生产率和结构尺寸,是主要设计参数。本研究以方草捆压捆机为试验设备,以羊草作为试验物料,研究开式压缩中压缩频率与压缩室三维应力的关系。在压捆机工作过程中,采集压缩过程中草物料在压缩室3个相互垂直方向上应力,分析三维应力间的相互关系,以及不同压缩频率下三维应力的变化趋势。结果表明:同一压缩频率下,三维应力值均随时间呈指数规律变化;压缩频率改变导致三维应力数值变化,但对三维应力本身变化规律无明显影响;单纯提高压缩频率会造成活塞轴向压缩力下降,进而影响其他两个方向应力。     

副溶血弧菌耐热直接溶血毒素的急性毒性研究

为研究耐热直接溶血毒素(TDH)对实验小鼠的急性毒性,经腹腔注射实验小鼠不同浓度梯度的TDH(42.0、19.5、9.1、4.2和1.9mg·kg~(-1)体重,对照组设为PBS),连续观察14d,记录各组小鼠的死亡情况及生理反应。实验终止时进行大体解剖,摘取心脏、肝脏、脾脏、肺和肾脏观测脏器指数,断尾采血并计数血细胞。结果表明,TDH对昆明种小鼠的半数致死量LD_(50)为11.0 mg·kg~(-1)体重,小鼠的死亡主要集中发生在注射TDH后的72 h内,并且伴随着腹泻现象。各组存活的实验小鼠在注射TDH后的第5天后,精神状态基本恢复,正常进食进水。各组小鼠脏器未见明显炎症反应,小鼠血液中红细胞与白细胞数量也未见统计学差异。TDH的毒性靶器官是心脏、肺、肾脏、脾脏、胃和肠。TDH对小鼠的半数致死量和毒性靶器官及病理学表现可为TDH的进一步实际应用及研究提供科学的依据和资料。     

压砂地中晚熟西瓜主要性状的遗传效应及其配合力分析

为提高压砂地中晚熟西瓜品种的种类数量及抗性,选用4份中晚熟西瓜自交系为亲本材料。采用Griffing方法Ⅳ配制杂交组合6个。对4个亲本及F1代的7个主要数量性状进行方差和配合力分析。结果表明,‘W08-15’各性状一般配合力效应值较高,综合性状表现优良,中晚熟西瓜品种选育可用其作为主要亲本来使用。在特殊配合力相对效应值上‘,W03-15×W08-15’是比较优良的杂交组合。在遗传力分析中,单果质量、果皮硬度、果肉硬度和维生素C含量分别具有较大的广义遗传力和狭义遗传力。该结果可为压砂地中晚熟西瓜杂交育种的亲本选择和选配提供依据。     

20％嗯唑酰草胺·灭草松ME防除水稻直播田一年生杂草及安全性

通过对20％曙唑酰草胺·灭草松ME防除水稻直播田一年生杂草及对水稻安全性的试验,明确了每667111。用20％嗯唑酰草胺·灭草松ME在有效剂量下,与10％韩秋好EC、48％灭草松AS相比较除草效果显著,杀草谱广;在水稻直播田中,当水稻秧苗2叶期后,杂草处于2～4叶期,用剂量为210—240mL／667m2（630—720a．i．g／hm2）时,能有效地防除水稻直播田一年生单双子杂草和异型莎草,证明了在水稻直播田应用吧唑酰草胺·20％灭草松ME对水稻是安全的。     

Rapid diagnosis of sulfonylurea‐resistant Schoenoplectus juncoides [Roxb.] Palla using polymerase chain reaction–restriction fragment length polymorphism and isogene‐specific direct sequencing

Rapid diagnostic methods to detect known mutations in acetolactate synthase (ALS) genes that confer sulfonylurea (SU) resistance to Schoenoplectus juncoides were developed in this study. By using 11 SU‐resistant accessions (nine accessions with a Pro₁₉₇ substitution in ALS1 or ALS2, one accession with an Asp₃₇₆Glu substitution in ALS2 and one accession with a Trp₅₇₄Leu substitution in ALS2), polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) analysis for DNA fragments that were amplified simultaneously from genomic ALS1 and ALS2 and PCR–RFLP analysis for DNA fragments that were amplified from either of the genomic ALS1 or ALS2 were carried out. In each of the two PCR–RFLP analyses, a common PCR product was digested separately with the restriction enzymes, BspLI, MboI and MunI, in order to detect Pro₁₉₇ substitutions, an Asp₃₇₆Glu substitution and a Trp₅₇₄Leu substitution, respectively. In each of the lanes where the detection of SU‐resistant substitutions was aimed, a specific band to suggest the existence of the said substitutions was observed in theoretically assumable ways. Separately, a direct sequencing method also was established, which was able to selectively sequence ALS1 or ALS2 from common templates containing both ALS1 and ALS2 by the isogene‐selective primers that were designed to anneal either of the ALS genes. It is expected that these methods could be used for the genetic analysis of SU‐resistant S. juncoides by providing rapid and accurate diagnosis.     

Weed Flora of Andhra Pradesh

Abstract

A large scale white grub control campaign was launched by the Marathwada Agricultural University, Parbhani. Pit trapping indicated that there was an initial beetle population of about 50 million in an area of 876 ha. About 9,000,000 beetles were collected mechanically and destroyed. One spraying of 12,000 babul and neem trees with 0.4% DDT killed 88% of the beetles. The percentage reduction in the plant population of rice, chillies, jowar and sugarcane, due to white grub attack was 1.83, 6.34, 3.59 and 3.02 in the treated area as against 65.54, 56.06, 49.68 and 8.94 in the untreated area. In cotton there was no reduction in plant population in the treated area. There was an increase in yield in paddy, chilli, cotton and jowar to the extent of 164.5, 102.2, 27.8 and 12.7% respectively in the treated area of Ratoli. There was an 80% reduction in the white grub larval population.     

Direct and Residual Effects of Micronutrients on Crops in a Pattern in Floodplain Soil

ABSTRACT

Different micronutrients have variable residual effects in the soil. Again, crops have variability in their response to applied micronutrient. An experiment was conducted in floodplain soil of Bangladesh using cauliflower, maize, and rice in a pattern to explore differential effects of micronutrients on crops. Seven treatments following additive element trial technique including a control were used in the study. Micronutrients were applied @ 3 kg Zn, 2 kg B, 2 kg Cu, 3 kg Mn, 5 kg Fe and 1 kg Mo per hectare. Cauliflower as the first crop of the pattern responded to direct application of both zinc and boron whereas significant residual effects of these elements were observed in the second crop (maize). In rice as the third crop, no significant residual effects were estimated. In floodplain soil, zinc and boron fertilizers are needed to apply in each third crop of a pattern where the second crop is nutrient exhaustive like maize.     

不同模压成型条件下聚丙烯木塑复合材料性能

为利用农林废弃物和环境保护,以稻秸秆粉、稻壳粉、木粉、竹粉及稻秸秆与木粉的混合粉为填充材料,以PP膜为基体材料,采用层铺模压和混炼模压2种成型方法制备不同填料PP木塑复合材料,对木塑复合材料力学性能和吸湿吸水性能进行测试和分析,用体视显微镜对复合材料拉伸断面进行观察。结果表明,混炼模压成型木塑复合材料力学性能和抗吸湿吸水性能均优于层铺模压木塑复合材料,且混炼模压PP木塑复合材料填充材料与基体之间混合均匀,两相界面之间结合良好,层铺模压PP木塑复合材料有植物纤维粉和PP基体堆积现象。稻秸秆粉制备的PP木塑复合材料综合力学性能较好,竹粉PP木塑复合材料力学性能较差,模压前混炼对PP木塑复合材料吸湿、吸水性有较大的改善作用。该研究可为利用废旧塑料膜作基体制备木塑复合材料的研究与生产提供参考。