试验结果表明,在烤烟移栽期低温、生育前期干旱的生态区,浅"V"型垄地膜覆盖模式对提高地温和土壤的含水量作用显著,能增加培土高度,对烟苗早发快长,促进根系的发育创造了良好的条件.为提高烟株的吸收功能,促进烟株正常生长,增强抗性,提高烟叶的产量、质量、效益都具有积极的作用.

Seven field experiments using a uniform test design and cultivated mode were simultaneously carried out in7provinces to study the characteristics of accumulation and distribution of boron in tobacco.The results show ed that the concentration of B in leaf and sucker was higher than that in root and stem,and was higher in north than that in south,while the concentration of B in stem and root proved higher in south than that in north.The curve of boron accumulation in tobacco was similar to Logistic one of plant growth in different ecosystems.In general,the characteristics of B accumulation in north were similar to those in south in the early stage of tobacco growth,but the amount and intensity of B accumulation in north in the30days after transplantation were much more than that in south.The proportion of B accumu-lation in60days in south was higher than that in north but inverted after that.The contents of B in the tobacco plant could be enhanced by higher pH,total N and available N,but it was negatively affected by higher amount of organic matter in soils.The B accumulation in tobacco during its growth and development was highly positively correlated with average temperature,maximum temperature,10cm soil temperature and light hour.

通过对烤烟根系与烟叶产质关系研究,结果表明,烤烟根系发育与烟叶生长、抗病性、主要经济性状、烟叶化学成分和吸食品质有密切的关系.随着根重的增加,烟叶生长加快,对病毒病的抗性增强,同时烟叶化学成分趋于协调,烟叶评吸品质提高.根系的发育与合理的栽培措施密切相关,通过实施揭膜培土、适当推迟移栽期、采取合理的盖膜方式、施用腐熟秸秆和保得生物肥等措施,可有效改善根系生长发育环境,促进根系发育.

初步探讨了不同产地烟叶化学成分年度间的稳定性，结果显示：各烟区化学成分含量年度间都会出现某些波动，以糖／碱和氮／碱的变化最大，其次是烟碱。辽宁开原烟叶的化学成分年度间稳定性最差，豫鲁四县烟叶的化学成分年度间稳定性最好。还原糖、烟碱、总氮、氯、糖／碱年度间的稳定性都是南方好于北方，而钾、蛋白质、氮／碱年度间稳定性北方好于南方。

中烟99系选用烤烟新品系88-4009与中烟86杂交,杂种F1经花培纯化定向选育而成,2000年12月通过全国烟草品种审定.该品种较耐肥水,田间生长势强,优质烟成熟特征明显,分层落黄好,易烘烤;烤后原烟金黄至桔黄,油分多,色泽鲜亮,化学成分协调,烟叶质量符合目前卷烟工业要求;兼抗黑胫病、赤星病和气候斑点病,耐普通花叶病,比对照品种产量提高5.64%,均价提高8.19%,中上等烟增加5.93个百分点,单位面积产值提高11.28%;是一个品质、抗性、产量、适应性等方面较能兼顾,适宜于黄淮、东北烟区种植的优良新品种.

Root-knot disease is one of the most important diseases on tobacco in Shandong Province,39 samples were collected from 12 counties of the main tobacco-planting areas of Shandong.Morphology and host test rest revealed that 23 of the samples were Meloidogyne incognita race 1,accounting for 58.97% of the collected population.9 samples were Meloidogyne javanica,accounting for 23.08%.7 samples were Meloidogyne arenaria race 2,accounting for 17.95%.This indicated the dominancy of Meloidogyne incognita race 1 with an increasing population of the other species in the pathogen population of tobacco root-knot nematode in Shandong.