Abstract: In order to clarify the effect of phosphorus deficiency on root development and nutrient uptake of sweet potato.The sweet potato named Yanshu 25 was used as the experimental material,two treatments of phosphorus deficiency (P0) and normal phosphorus supply (P1) was set up,the growth characteristics and nutrient uptake of sweet potato roots under phosphorus deficiency were studied by gravel culture.The results showed that P deficiency could inhibit the growth of shoots and root parts of sweet potato and reduce the shoot and root biomass.Compared with normal phosphate,the total surface area,total root volume,the number of root tips and average diameter of sweet potato root increased with the prolongation of culture time,but its root activity decreased,total volume and total biomass were significantly lower than those of normal supply phosphorus treatment; Phosphorus deficiency could significantly increased the absorption of N,K,Ca,Mn,Cu in sweet potato root system,decreased the absorption of Mg,Fe in root system,while the N,K,Mg,Mn,Cu content increased and the Ca,Fe content decreased in shoot.Based on the above test results,phosphorus deficiency caused the growth and development of sweet potato ground and underground,but the sweet potato adapt to the lack of phosphorus environment by adjusting the root system and other root developmental parameters,so as to alleviate the effect of phosphorus deficiency on root nutrient uptake.

Key words: Sweet potato, Phosphorus deficiency stress, Root development, Root activity, Nutrient absorption

CLC Number: 

• S143.2