硼肥不同施用量对烟草生长发育的影响

Effects of Different Boron Fertilizer Application Amount on Growth and Development of Tobacco

烟草对硼比较敏感，施用硼肥，烟草的生物学及经济性状均有所改善。研究结果表明，烟草施硼肥以土施１５ｋｇ·ｈｍ－２为宜。此与对照相比，圆顶期株高增加５８ｃｍ，单株叶数增加１１片，中部叶叶面积增加４０２ｃｍ２，说明硼对烟草生长发育有明显促进作用。施硼还能增强烟草抵抗花叶病能力，促烟提早落黄，烟叶均价与产值均有所增加。施用１５ｋｇ·ｈｍ－２硼砂与不施肥对照相比，均价增加０４元，增幅为７２７％，差异达５％显著水平，上等烟比例增加４０７％，产值增加１４２３５元，增幅为１０２７％，差异达极显著水平。试验结果亦表明，施用３０ｋｇ·ｈｍ－２硼砂，即对烟叶生长发育产生不利影响。

Tobacco is sensitive to boron.Applying boron fertilizer could improve the biological and economical characteristics.The results showed that the optimum application amount was 15kg per hectare when boron was fertilized into the soil.Compared with CK,leaf number in phase incraeasd by o.3pieces per plant,the plant height was 5.8cm higher ,and the leaf area increased by 40.2 cm 2 on the middle parts of the plant. Analyses above showed that boron fertilizer had a great promoting effect on the growth of tobacco plant.Moreover,resistence to mosaic disease of the plant increased,the leaves grew yellow earlier,and the average price and the value of output per unit area of soil were raised to some extent in treated plots.The average price per unit weight of tobacco leaves was significantly raised by 0.40 yuan RMB ,or by 7.27%;and the ratio of quality tobacco leaves to common ones increaed by 4.07%. Therefore,the value of output per hectare increased by 10.27%,or 1423.5 yuan PMB ,and the difference was extremely significant.Furthermore,the results also showed that there would be a harmful effect on growth of the tobacco plant if application rate of boron fertilizer went beyond 30kg per hectare or more.