Effect of Polyacrylamide Application Rate on Photosynthetic Characteristics and Yield of Black Highland Barley
HUANG Huiyun
QI Wenjing
FU Tiantian
FENG Xibo
Abstract：To investigate the effects of polyacrylamide application on photosynthetic characteristics and biomass of black highland barley and provide a theoretical basis for the rational application of polyacrylamide in high-yield and stable-yield cultivation of highland barley,a single-factor randomized block design was employed.Using Longzi highland barley as the experimental material,five treatments with different polyacrylamide application rates were established:P0(0 kg/hm2,control),P1(6 kg/hm2),P2(12 kg/hm2),P3(18 kg/hm2),and P4(24 kg/hm2).The study compared the trends in photosynthetic characteristics,biomass,yield,and yield components of flag leaves under different polyacrylamide treatments.The results showed that:(1)Polyacrylamide application significantly enhanced the photosynthetic performance of flag leaves post-anthesis(P＜0.05),with the P2 treatment showing the most pronounced effect.The SPAD value,stomatal conductance,and transpiration rate of flag leaves peaked at 14 days post-anthesis,and P2 increased these parameters by 17.52%,27.95%,and 18.39%,respectively,compared to P0.The intercellular CO2 concentration peaked at 35 days post-anthesis,and P2 showing a 22.91%increase over P0.The net photosynthetic rate peaked at 7 days post-anthesis,with P2 demonstrating a 32.04%increase over P0.(2)Polyacrylamide application increased the biomass and root-shoot ratio of black highland barley.Compared to P0,the biomass under P1,P2,P3 and P4 treatments increased by 31.58%,64.10%,48.19%and 13.86%,respectively,while the root-shoot ratio increased by 2.60%,6.49%,5.19%and 1.30%,respectively.(3)Polyacrylamide application enhanced the yield of black highland barley.Among all the treatments,the yield of black barley under P2 treatment was the highest,reaching 6 588.08 kg/hm2.Therefore,an application rate of 12 kg/hm2 of polyacrylamide effectively improves the photosynthetic characteristics,biomass and yield of highland barley.
Keywords：PolyacrylamidBlack highland barleyPhotosynthetic characteristicsBiomassYield
Publication Date：2025-08-28
Online Publishing Date：2025-09-23(First online date of this platform, not the publication date of the document)
Pages：6( 10-15 )