种植密度和氮肥用量对百色烟区烤烟叶片发育及烟叶产量的影响

Effects of Planting Density and Nitrogen Fertilizer Application Rate on Leaf Development and Yield of Flue-Cured Tobacco in Baise Tobacco Region

为明确不同种植密度和氮肥用量下烤烟的干物质积累、分配情况及烤烟中、上部叶的发育特征,以K326为试验材料,设置种植密度和氮肥用量两因素随机区组试验,分析影响烤烟群体和个体干物质积累的叶片发育特征。结果表明,种植密度和氮肥用量对烤烟成熟期单株叶片干物质积累量均有极显著影响;成熟期烤烟单株叶片干物质积累量、整株干物质积累量、冠根比受种植密度和氮肥用量极显著交互效应的影响。施氮提高了烤烟中、上部叶现蕾期时的比叶重和叶片密度,种植密度对现蕾期和成熟期的中、上部叶单叶重及比叶重的影响均达到了极显著水平。烤烟叶片发育与干物质积累的相关分析表明,成熟期烤烟中部叶的比叶重和烤烟单株干物质积累量呈显著正相关,上部叶的叶片厚度与烤烟群体干物质积累量呈正相关。在低密度条件下,氮肥用量112.5 kg N/hm^(2)时烤烟上等烟比例达73.35%,在中等密度下,氮肥用量112.5 kg N/hm^(2)时烤烟产量、产值和均价达到各处理的最大值。综合考虑,在广西百色烟区周年烟稻轮作种植模式下,种植密度1.82万株/hm^(2)、基施氮肥用量112.5 kg N/hm^(2)处理能实现烤烟K326的最佳经济效益。

To clarify the dry matter accumulation,distribution,and the development characteristics of the middle and upper leaves of flue-cured tobacco with different planting densities and N fertilizer application rates,K326 was used as the test material and two-factor randomized group trials were set up with planting densities and N fertilizer application rates.The leaf developmental characteristics affecting dry matter accumulation in flue-cured tobacco populations and individuals was analyzed.The results showed that planting density and N fertilizer application rate had an extremely significant influence on dry matter accumulation of leaves at maturity stage.There were significant interaction effects between planting density and N fertilizer application rate on dry matter accumulation of leaves and whole plant,as well as shoot-root ratio.At budding stage,applying nitrogen increased the leaf mass per area and leaf density of the middle and upper leaves.The effects of planting density on leaf weight and leaf mass per area of middle and upper leaves reached highly significant levels.The correlation between leaf development and dry matter accumulation in flue-cured tobacco showed the leaf thickness of the upper leaves was positively correlated with the dry matter accumulation of the flue-cured tobacco population.In low-density conditions,the proportion of top-quality flue-cured tobacco reached 73.35%at an N fertilizer application rate of 112.5 kg/ha,and the yield,production value,and average price of the same N treatment reached the highest among all treatments under normal planting density(D2).In Baise tobacco area,under the annual tobacco and rice rotation planting mode and the planting density of 1.82×10^(4) plant/ha,the best economic benefit of flue-cured tobacco K326 can be achieved when the amount of base nitrogen fertilizer is 112.5 kg N/ha.