【摘要】 【目的】筛选耐低磷及磷高效作物是充分利用土壤磷素和磷肥,减少磷肥施用对环境污染的重要手段。调查烟草基因型的磷素利用效率可为培育磷高效烟草品种提供理论依据。【方法】以71个烟草品种为供试材料进行了水培试验。以Hoagland营养液为基础（1.0 mmol/L KH₂PO₄）,调整营养液磷水平0.01 mmol/L KH₂PO₄ （低磷）。烟苗在完全营养液中生长至4叶1心时进行处理。处理21天后,采样分析烟草主要生长、形态和生理指标,筛选耐低磷基因型判别指标,并对品种进行磷效率类型划分。【结果】全株磷累积量、地上部干重、根干重、株高、总根长及根直径可作为鉴定耐低磷烟草基因型的苗期筛选指标。将全株磷累积量和地上部干重的耐低磷相对值进行聚类热图分析,鉴定出8个耐低磷品种、21个低磷敏感品种及42个中间型品种。同时,依磷效率综合值作散点图发现,耐低磷品种中有4个低磷低效正常磷低效型、2个低磷高效正常磷高效型和2个低磷高效正常磷低效型,低磷敏感品种中有14个低磷低效正常磷低效型、1个低磷高效正常磷高效型和6个低磷低效正常磷高效型。【结论】初步确定K326和云烟105为耐低磷且磷高效品种,G28、闵烟3号、DB101、Oxford 2028、14P10、CV70、云烟98、MSB44、单育2号、净叶黄、CB1、中烟101、RG11和MSB31等14个为不耐低磷且磷低效品种。更多还原

【Abstract】 【Objectives】Screening crop genotypes with low-Pi tolerant and Pi-high-efficiency is of great significance for improving the phosphate utilization efficiency, decreasing the phosphate fertilizer input, and lowering the potential environmental risks caused by excess phosphate application. This study is to investigate the Pi use efficiencies of tobacco and its Pi efficiency characteristics,and thus providing a reference for the Pefficient cultivar breeding.【Methods】A hydroponic experiment with low-Pi(0.01 mmol/L) or normal-Pi(1.0 mmol/L) supply was conducted, a total of 71 seedlings of tobacco genotypes was collected for the tested materials.All the seedlings were grown in normal Pi nutrient solution until the fifth leaf sprout, then treated with low-Pi for21 days. The main developmental, morphological and physiological indexes of the tobacco seedling were measured, the index for low-Pi tolerance were screened, and the Pi efficiency of genotypes were classified under low-Pi stress.【Results】The total plant P accumulation, biomass of aboveground and root parts, plant height,total root length and root diameter were used as indexes to screen the seedling of low-Pi tolerant tobacco genotypes. Using the heatmap clustering analyses, the relative values of total P accumulation and aboveground biomass, 8 of low-Pi tolerant genotypes, 21 of low-Pi sensitive genotypes and 42 of medium genotypes were identified, respectively. Meanwhile, scatter diagram analyses on Pi efficiency comprehensive value showed the presences of total 4 types with low-efficiency under both low-Pi and normal-Pi, total 2 types with high-Pefficiency under both low-Pi and normal-Pi, and 2 types with P-high-efficiency under low-Pi but low-efficiency under normal-Pi in low-Pi tolerant genotypes, and total 14 types with low-efficiency under both low-Pi and normal-Pi, and only 1 types with Pi-high-efficiency under both low-Pi and normal-Pi, and total 6 types with lowefficiency under low-Pi but high-efficiency under normal-Pi in low-Pi sensitive genotypes.【Conclusions】We primarily concluded that the K326 and Yunyan 105 are identified to be the low-Pi tolerant and P-efficient genotypes, and the G28, minyan 3, DB101, Oxford 2028, 14 P10, CV70, yunyan98, MSB44, danyu 2,jingyehuang, CB1, Zhongyan101, RG11 and MSB31 are identified to be the low-Pi sensitive and P-insensitive genotypes.更多还原