The Study On Relationship Between The Agronomic Characters And Yields Of Quinoa And Phosphorus And Potassium Fertilizer

In this paper,a field trial of randomized block design is conducted to study the effects of phosphorus and potassium fertilizers on the main biological and yield traits of Quinoa.The results show that"Long Quinoa No.1"sown in Northwest China in May,after about121 days later can be normal maturity,phosphorus and potassium fertilizers have no effect on the growth period of Quinoa.The plant height of Quinoa has been increasing continuously from emergence to flowering.The treatment of phosphorus fertilizer can increase the plant height of Quinoa and only in the case of high potassium it increase obviously.The fastest growing period of Quinoa is late branching to early budding in the late June to early July,the highest increasing rate of daily reaches to 5.98cm/day,The plant height is still growing at early flowering stage,but the increasing rate of plant height gradually tends to be slow.With the growth of plant,stem diameter gradually thickens,and then entering the mature stage,stem diameter tends to be stable.Phosphorus and potassium fertilizer treatment can obviously increase Quinoa stem diameter.Quinoa completes the growth of primary number of branches in the end June to early July,The primary number of branches could reach a maximum of 31,high phosphorus and low potassium fertilizer can obviously promote the Quinoa primary number branches growth.Quinoa reached to the maximum number of leaves at flowering stage.Phosphorus and potassium fertilizer has a significant effect on the increase of leaves number in the late growth of Quinoa.Phosphorus and potassium fertilizer can increase the fresh biomass of Quinoa,The highest biomass is treatment K₃P₃ with high phosphorus and potassium in more than 348.5g.The lowest fresh biomass is treatment P0K0 reached to 294.7g.The application of phosphorus and potassium fertilizer can improve the dry biomass per plant of Quinoa,Under middle or high phosphorus and potassium levels Quinoa dry biomass improves obviously.The dry biomass weight of treatment P₂K₂ and P₃K₂ are highest up to 262.3g,and treatment P₃K₃ is second up to 261g,and the lowest dry biomass weight is treatment P0K1 just 218.2g.Compared with the control group,the average spike number per plant in each treatment is higher than that in the control group.The average spike number per plant in treatment P3K1 is most up to 29,followed by P3K3 is26,and the lowest is treatment P0K0 just 20.Low and middle level phosphorus and potassium fertilizer can obviously increase the main stem spike weight.The highest main stem spike weight is treatment P₂K₁ in more than 16.92g,followed is treatment P₁K₂,P₁K₁ and P₂K₂,respectively,16.77g,16.72g and 16.35g,and the lowest is control group P0K0 just 14.1g.The lateral spike weight also increases at medium phosphorus and potassium level.The highest spike weight of treatment P2K2 is 53.02g and the lowest is control group 46.05g.The phosphorus and potassium fertilizer can increase total Quinoa spike weight.And medium phosphorus and potassium fertilizer level is more advantageous to promote Quinoa total spike weight.The maximum total spike weight of P₂K₂ is 69.4g,while the lowest total spike weight of the control is 60.1g.The main grain weight of the main stem have the same relationship with the main stem spike weight.Among them,the main grain weight of main stem of P₁K₂ is 6.05g,followed by P₂K₁ and P₂K₂ is 5.68g and the lowest P₀K₃ is 4.63g.Compared with the grain weight of lateral spike,the maximum of the treatment P₂K₁ is 24.68g,and the minimum of the treatment P₀K₁ is20.92g.Compared with total grain weight of single plant,The maximum of the treatment P₂K₁ is30.37g,and the minimum of treatment of P₂K₁ is 25.67g.Low level potassium fertilizer of medium level phosphate fertilizer can obtain higher yield per plant.The grain of Quinoa with medium phosphorus and low potassium fertilizer is the most full,and the maximum weight of1000 grain of treatment P₂K₁ is 2.73g.which may also be the reason for the high yield of middle and low phosphorus and potassium fertilizer.We found that 1000 grain weight treatment P₃K₃was the lowest,indicating that excessive application of phosphorus and potassium instead lead to full reduction of Quinoa grains,which may be that high phosphorus and potassium leading to Quinoa branching more,During the ripening of the ear,the ineffective nutrient consumption is more,and the dry matter can not be effectively transported to the target reservoir（grain）.although the yield is not low,but the maturity of the grain of Quinoa is poor,Therefore,phosphorus and potassium fertilizer can not be applied blindly in the production of Quinoa.The highest yield per unit area of treatment P₂K₂ is 207.10g,followed by treatment P₂K₁ is 205.80g,and the lowest yield per unit area of treatment P₀K₁ is 178.8g.