长城沿线农牧交错区退化草场恢复对策——以宁夏盐池沙地退化草场为例

描述了长城沿线农牧交错区天然草场退化现状,指出退化主要原因是干旱少雨、超载放牧、滥垦和不合理利用土地、滥采乱挖。针对天然草场退化现状,提出通过围栏封育,灭杂草,鼠虫害防治等技术对退化草场进行改良。针对草场利用中存在的问题,提出建立合理的放牧制度,实行以草定畜、加强畜牧业基础设施建设、优化畜群结构、压缩耕地、发展人工草地等措施促进退化天然草场植被恢复。为北方长城沿线农牧交错区退化草场植被恢复、生态建设提供技术支撑和政策依据。     

辣椒疫霉菌毒素的初步研究

辣椒疫霉病菌 (Phytophthora capsici)在胡萝卜(CFB)培养液中易于培养及产生毒素。生物测定表明:P.capsici毒素溶液能抑制辣椒、绿豆、豇豆和黄瓜种子胚根生长,损伤辣椒叶片细胞膜,对幼苗有强烈的致萎作用。寄主表现出病原菌侵染相似的症状。     

猕猴桃蛋白酶提取的工艺技术研究

采用盐析沉淀法,配合等电点沉淀法,对猕猴桃蛋白酶提取的工艺技术进行了研究。初步选定的工艺条件为:果汁与水的比例为1∶1,食盐水浓度为22.5%~25%(W/V),pH值范围在4.0~4.8间,低温沉淀8~10 h。粗酶的平均提取率约为0.765%。     

不同玉米品种萌芽期抗旱性研究

通过PEG渗透胁迫人工模拟干旱条件，对不同的玉米品种川单15号、黔单11号、户单2000、成单19、安单136、黔单13号、三北六号、农大3138、正红6号进行了萌芽期抗旱性研究。结果表明：水分胁迫降低了各玉米品种的发芽势和发芽率，阻碍了胚芽和胚根的生长，降低了种子中贮藏物质的利用效率。但不同的玉米品种在抗旱性上存在极显著差异，抗旱性强的品种在水分胁迫下仍然保持较高的发芽势和发芽率。通过对上述指标的测定可以较好地反映出玉米品种萌芽期的抗旱性。     

水稻条纹病毒的分子生物学与抗病基因工程研究进展

综述了国内外近年来对水稻条纹病毒的基因组结构、复制、转录、功能、分子变异和基因工程应用等方面的最新研究进展。     

阜新市葡萄生产存在的问题及发展对策

葡萄在阜新市已有60多年的栽培历史,实践证明葡萄生产是阜新市农业生产中的重要组成部分,具有很大的发展潜力.到目前为止,葡萄面积已发展到2667hm^2,占全市水果总面积的13.3%;年产量4万t,占全市水果总产量的33.3%.     

玉米主要性状间的灰色关联度分析

运用灰色关联度分析法，对12个玉米杂交组合的14个主要性状间的相互关系进行了研究分析。结果表明：与产量关系密切的是穗长、百粒重、穗粗、行粒数，其次是株高、穗位高度、茎粗、叶面积指数；增加穗长、行粒数、株高、穗位高度、茎粗可以提高蛋白质、脂肪、淀粉、赖氨酸的含量。     

化学药剂防治大豆幼苗疫病的效果研究

选用甲霜灵(Metalaxyl)为主要成份开发出ND98-1种衣剂,用量在3%以内对大豆生长安全,种子包衣用药量为3%时,防效为95.2%,持效期可达30～40 d(即至开花期),持效期比用58%雷多米尔(WP)拌种多15～20 d。大田示范试验中,平均增产率为32.7%。     

播种量对油菜毯苗生长的影响

探究播种量对油菜毯苗生长的影响,对标准化的油菜毯苗培育具有重要的现实意义。本试验测定了不同播种量下两个油菜品种的出苗数、存苗数、地上部生物量、叶片与根颈的生长状况。其结果显示:提高播种量会显著降低油菜毯苗的出苗率、存苗率、地上部单株干重、子叶与真叶的大小和根颈直径,提高油菜毯苗的株高与根颈长。但通过播种量的增加可以一定程度弥补质量的下降,使油菜毯苗的地上部全盘总干重先增加后减小。根据实际生产的移栽需求,通过播种量与存苗数的回归分析结果显示,最适播种量为700~750粒/盘。     

Analysis of Blast Resistance Genes and Neck Blast Resistance of japonica Rice Varieties/Lines Recently Developed in Jiangsu Province

【Objective】Evaluating the breeding potential of the known blast resistance (R) genes harbored in rice varieties is one of prerequisites for developing rice blast resistant varieties and R genes-based control of the disease epidemic.【Method】A total of 195 new japonica varieties/lines from Jiangsu Province were genotyped using functional markers corresponding to 14 rice blast R gene loci. In order to identify gene or gene combination with breeding potential against neck-blast, 158 japonica rice varieties were then artificially inoculated with blast strains as well as 17 advanced backcrossing lines containing Pigm gene in two different genetic backgrounds at booting stage. 【Result】Most varieties carried 2 to 5 R genes, and none of new varieties contained Pigm; the distribution frequencies of Pib, Pita and Pikh were relatively high and all exceeded 45%, the rest 10 genes were under 30%; Pid3, Pid2, Pia and Pb1 had apparently higher frequency in lines from regional tests than that in authorized and released varieties. Three genes with effects ordered as Pia > Pi3/5/i > Pita significantly contributed to neck-blast resistance, and significantly positive interaction effects were found between Pia and Pita, and between Pi3/5/i and Pita. Combination effect of Pia+Pita was significantly higher than that of Pi3/5/i+Pita, and the varieties harboring Pia+Pita reached resistant or highly resistant levels. The resistance of 17 advanced backcrossing lines carrying Pigm was all significantly improved as compared with corresponding controls, and all reached resistant level or even higher. 【Conclusion】 The results suggested that Pigm and the combination of Pia+Pita have critically important breeding potential in japonica rice breeding against neck blast in Jiangsu Province.