磷肥用量对甜荞Fagopyrum esculentum根系形态、产量及品质的影响

Effects of Phosphate Fertilization on Soil Fertility and Plant Morphology,Grain Yield and Quality of Fagopyrum esculentum

【目的】明确磷肥用量对甜荞根系形态、产量形成和籽粒品质的影响。【方法】以甜荞品种丰甜1号为试验材料,设置不施磷(CK,0 kg·hm^-2)、低磷(LP,35 kg·hm^-2)、中磷(MP,70 kg·hm^-2)和高磷(HP,105 kg·hm^-2)4个处理,研究磷肥用量对丰甜1号根际土壤速效养分、根系形态、最终产量和籽粒品质的影响。【结果】根际土壤的速效氮、速效磷、速效钾和有机质含量随磷肥用量的增加而呈先增加后降低的趋势,均以中磷(MP)处理时达最大;根际土壤pH则随磷肥用量的增加表现为持续下降。丰甜1号的根系总长度、根系体积、根系表面积以MP处理显著高于其他处理,磷肥处理间的根系平均直径无显著差异。丰甜1号的株高等植物学性状和产量随磷肥用量的增加呈先增加后降低的趋势,均以MP处理最大,其中MP处理时的产量为对照(CK)处理的1.43倍。丰甜1号籽粒中的品质随磷肥用量的增加呈先增后降的趋势,黄酮含量以CK处理最大,高磷(HP)处理最低。【结论】中等用量的磷肥处理(70 kg·hm^-2)能促进甜荞生长、提高产量和品质。

【Objective】Effects of phosphate(P)fertilizer on the soil fertility and the plant morphology,available nutrients,and grain yield and quality of common buckwheat,Fagopyrum esculentum,were investigated.【Method】A high yield buckwheat,Fengtian 1(FT1),was cultivated under P fertilization at 0 kg·hm^-2 P(CK),35 kg·hm^-2 P(LP),70 kg·hm^-2 P(MP)or 105 kg·hm^-2 P(HP).Effects of the fertilizations on the soil nutrient contents as well as the root morphology,aboveground botanical characteristics,and yield of the buckwheat plants were determined.【Result】The increased P fertilizer applications enhanced the contents of available nutrients and organic matters in soil with a peak under MP.But the soil pH was on a continuous downward trend upon increasing P.For the plants,the root length,volume,and surface area reached their highest levels with MP as well.However,the root diameter was not significantly affected by the changes on the application.Morphologically,the plant height,node and branch numbers on main stems,1-to 2-internode length,1-to 2-internode diameter,and grain yield increased significantly under MP,much more than the other treatments.Again,the higher P in HP did not render further increases as MP did.Among all treatments,MP also delivered the greatest grain yield,which was 1.43 times that of CK.Similarly,the contents of protein,dietary fiber,rutin,quercetin,and kaempferol of the FT1 grains rose along with the increasing P application up to the level in MP.On the other hand,the flavonoid in the grains reached the highest level under CK and the lowest under HP.【Conclusion】It appeared that P fertilization in the amount of MP would be appropriate for the growth,grain yield and quality of FT1 plants.