Description
Legume seeds are the product of long-term natural selection and the co-evolution of rhizobia and seeds. They are more competitive than the native rhizobia in constructing symbiotic nitrogen-fixing systems with host plants. However, the paths and impact factors of rhizobia invasion and migration in plants, as well as colonization in seeds, are unclear. Here, alfalfa cultivars WL343HQ and Gannong 5, and three cyan fluorescent protein-tagged rhizobia (FTR), 3436f, 12531f and gn5f were used as materials. The effects of potassium dihydrogen phosphate (KH2PO4) and fulvic acid (FA) on the migration and colonization of FTR in the reproductive organs of field plants were explored after inoculated at flowering and pod-setting stages. It has been shown that the contribution of exogenous substances and the inoculation stages to FTR colonization in alfalfa seeds at six months post-harvest differs between alfalfa cultivars and FTR strains. For WL343HQ alfalfa, the pods sprayed with 3436f added with 0.01% FA, the flowers sprayed with 12531f added with 50 mg/L KH2PO4 and gn5f added with 0.08% FA produced seeds containing 3436f (23.08 cfu/seed), 12531f (22.69 cfu/seed) and gn5f (10.77 cfu/seed), respectively. For Gannong 5 alfalfa, the flowers sprayed with 3436f added with 200 mg/L KH2PO4 and gn5f added with 0.02% FA produced 3436f (27.69 cfu/seed) and gn5f (21.04 cfu/seed) colonized seeds, respectively. FA outperforms KH2PO4 in promoting the migration and colonization of FTR in the flower organs after inoculation at the flowering stage.
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Migration and Colonization Characteristics of Endophytic Tracer Rhizobia to the Reproductive Organs of Alfalfa
Legume seeds are the product of long-term natural selection and the co-evolution of rhizobia and seeds. They are more competitive than the native rhizobia in constructing symbiotic nitrogen-fixing systems with host plants. However, the paths and impact factors of rhizobia invasion and migration in plants, as well as colonization in seeds, are unclear. Here, alfalfa cultivars WL343HQ and Gannong 5, and three cyan fluorescent protein-tagged rhizobia (FTR), 3436f, 12531f and gn5f were used as materials. The effects of potassium dihydrogen phosphate (KH2PO4) and fulvic acid (FA) on the migration and colonization of FTR in the reproductive organs of field plants were explored after inoculated at flowering and pod-setting stages. It has been shown that the contribution of exogenous substances and the inoculation stages to FTR colonization in alfalfa seeds at six months post-harvest differs between alfalfa cultivars and FTR strains. For WL343HQ alfalfa, the pods sprayed with 3436f added with 0.01% FA, the flowers sprayed with 12531f added with 50 mg/L KH2PO4 and gn5f added with 0.08% FA produced seeds containing 3436f (23.08 cfu/seed), 12531f (22.69 cfu/seed) and gn5f (10.77 cfu/seed), respectively. For Gannong 5 alfalfa, the flowers sprayed with 3436f added with 200 mg/L KH2PO4 and gn5f added with 0.02% FA produced 3436f (27.69 cfu/seed) and gn5f (21.04 cfu/seed) colonized seeds, respectively. FA outperforms KH2PO4 in promoting the migration and colonization of FTR in the flower organs after inoculation at the flowering stage.
