【摘要】 为探讨硅肥对甘薯薯块产量形成的调控效应，选用鲜食型甘薯品种‘烟薯25’（Y25）和‘烟薯29’（Y29）为材料，进行为期2 a的大田生产试验和盆栽辅助调查试验。试验设置以空白处理（CK）为对照，不同硅肥处理分别为500倍浓度的液体水溶硅肥（单硅酸，SiO₂≥27%）喷施处理（P）、灌根处理（G）和喷施加灌根处理（P+G）,硅酸钠（Na₂SiO₃·9H₂O,AR） 90 kg/hm²（T9）、180 kg/hm²（T18）和360 kg/hm²（T36）的灌根处理。通过对不同硅肥处理收获期薯块产量、产量构成因素和贮藏期间的薯块完好度进行调查比较，分析2个甘薯品种差异处理植株生长前期关键节点茎叶、根系生物量积累分配、粗根解剖发育特点和 IbEXP1基因的表达来初步探究不同硅肥处理的调控效应。大田结果表明，和对照处理（CK）相比较，各硅肥处理均不同程度提高了2个甘薯品种茎叶封垄期（栽后50 d）、收获时鲜薯的可溶性固形物含量和收获贮藏60 d时薯块的完好率，初步明确了硅肥施用对甘薯鲜薯甜度及薯块耐储力的提升效应；其中水溶硅肥喷施处理（P）显著提高2个甘薯品种收获时的薯块产量，而硅酸钠3个浓度的灌根肥处理均不利于2个甘薯品种薯块产量的形成，该处理（P）的单株有效薯块数目与对照处理（CK）相比无显著差异，但提高了平均单薯鲜质量和中型薯块数目构成比率及其在最终薯块产量的贡献率，薯块整齐度更高，明确了水溶硅肥喷施处理（P）主要通过提高单薯质量而促进薯块产量的形成。水溶硅肥喷施处理（P）显著提高甘薯‘烟薯25’和‘烟薯29’收获时的薯块产量，增幅分别为14.06%和6.84%;差异处理的盆栽辅助试验表明，‘烟薯25’水溶硅肥喷施处理（P）植株在生长前期具有最强的生长势（最高的地上部生物量、全根系生物量和T/R比值，单株叶面积大、主茎长、吸收根生物量高）,栽后30 d发育根已发生初始膨大且根径最大，为最终薯块产量的形成奠定基础；而水溶硅肥灌根处理（G）和硅酸钠灌根处理（T36）植株在生长前期吸收根系生物量少，栽后15 d幼根表皮细胞硅质化和30 d时发育根 IbEXP1基因的高量表达，负调控薯块的膨大，不利于甘薯大田生产。更多还原

【Abstract】 To investigate the regulatory effect of exogenous silicon fertilizer on sweet potato storage root yield, this study selected ‘Yanshu 25’（Y25） and ‘Yanshu 29’（Y29） as analyzing varieties and arranged treatment groups consisted of water-soluble siliceous fertilizer 500x liquid（H₂SiO₃,SiO₂≥27%）,which was set for spraying treatment（P）,irrigating treatment（G） and combined spraying and irrigating treatment（P+G）,and sodium silicate solid fertilizer（Na₂SiO₃·9H₂O,AR） irrigating treatments integrated with three rates for 90 kg/hm²（T9）,180 kg/hm²（T18） and 360 kg/hm²（T36）.Using a two-year field and pot investigation experiment, with a check treatment received no silicon fertilizer supplement, we investigated and compared the storage root yield and yield components at harvest and the condition of storage root during storage period, and made researches on the biomass accumulation of top and root at early growing stage, anatomical observation on sweet potato tuber at root differentiation, and expression characteristics of IbEXP1 gene associated with tuber root formation among different treatment groups.The field experiment results offered the initial evidence to the improvement effect of silicon fertilizer application on the sweetness and the storage tolerance of sweet potato fresh root, and there were different degrees of higher total soluble solid of fresh root among different silicon fertilizer treatments at canopy closure period（50 days after planting） and harvest stored for 60 days.The water-soluble siliceous fertilizer 500x liquid spraying treatment（P） had significantly increased storage root yield, but had no obvious difference in valid tuber root number per plant compared with the control group（CK） at harvest between two sweet potato varieties.Meanwhile, P treatment possessed higher average fresh mass per root, the proportion of medium-sized root and their contribution to the final root tuber yield, which contributed to the uniform in size of storage root.P treatment significantly increased storage root yield by 14.06%（Y25） and 6.84%（Y29） compared with CK.Pot assisted experiment among the distinctive different treatment groups had show that Yanshu 25 under P treatment grew best, which had the most aboveground biomass, total root biomass, T/R ratio, the more leaf area per plant, main stem, and absorbed root biomass.Its root diameter was the biggest owing to initial thickening occurred at 30 days after planting, and laid foundation for final storage root yield.Meanwhile, G treatment and T36 treatment possessed the less absorbed root biomass at early growing stage, the silicification of epidermal cells of young roots at 15 days after planting, and the highest expression characteristics of IbEXP1 gene at 30 days after planting.The above conditions negatively regulated root thickening, and that was unfavourable for field production of sweet potato.更多还原