Effects of seed soaking with different seaweed fertilizer combinations on growth and development of alfalfa under saline-alkali stress

LIANG Zhiyan; FENG Changsong; DU Hongqi; LOU Zhiguo; LIU Lei

doi:10.13557/j.cnki.issn1002-2813.2025.15.013

Abstract：The experiment aimed to investigate the effects of seed soaking with different seaweed fertilizer combinations on growth and development of alfalfa under saline-alkali stress,and to identify optimal seaweed fertilizer seed-soaking agents for alfalfa cultivation in saline-alkali soils of the Yellow River floodplain.Using alfalfa Jinneng 5030 seeds were soaked with:distilled water(groups CK,SA),seaweed fertilizer(group JC),seaweed fertilizer+betaine(group JG),seaweed fertilizer+potassium dihydrogen phosphate(group JK),seaweed fertilizer+mancozeb(group JM),and seaweed fertilizer+thiophanate-methyl(group JT).Except for the group CK,which used distilled water for germination hydroponics,all other groups used a 40 mmol/L composite saline alkali solution.groups SA,JC,JG,JK,JM,JT were selected for field experiments to determine the germination rate,seedling height,root length,biomass accumulation,field agronomic traits and forage quality of alfalfa seedlings.Grey correlation analysis method was used to comprehensively analyze different soaking treatments.The results showed that compared with group SA,the germination potential of groups JK and JT was significantly increased(P＜0.05),and the germination rate of groups JK,JM,and JT was significantly increased(P＜0.05).Compared with group SA,the seedling height and dry weight of the five seed soaking treatments were significantly increased(P＜0.05),the root length of groups JK,JM,and JT was significantly increased(P＜0.05),and the fresh weight of groups JG and JM was significantly increased(P＜0.05).Compared with group SA,the number of seedlings and the plant height at mowing in groups JG,JK,JM,and JT were significantly increased(P＜0.05),and the fresh grass yield and dry grass yield in groups JM and JT were significantly increased(P＜0.05).Compared with group SA,the content of neutral detergent fiber in group JM was significantly increased(P＜0.05),while the content of crude fiber in groups JC and JM was significantly decreased(P＜0.05).The results of grey correlation analysis show that the weighted relational degree values of each group from high to low were as follows:group JT＞group JK＞group JM＞group JG＞group JC.The study shows that soaking seeds in an appropriate concentration of seaweed fertilizer combined with thiophanate-methyl can significantly increase the yield of alfalfa forage under saline-alkali stress and enhance the salt-alkali tolerance of alfalfa in the Yellow River floodplain.