Dalea aurea, D. candida, D. multiflora, and D. purpurea seedling herbage, root nitrogen, and dry matter yield as influenced by soil type, phosphorus amendment, and cowpea Rhizobium inoculant

Abstract

Dalea aurea Nutt. ex Pursh (Fabaceae; golden prairie clover), D. multiflora (Nutt.) Shinners (roundhead prairie clover), D. purpurea Vent. (purple prairie clover), and D. candida Michx. ex Willd. (white prairie clover) are native to prairies and hillsides of the southern Great Plains. Herbage dry matter yield (DMY), root DMY, herbage nitrogen (N) DMY, root N DMY, and herbage N content were evaluated in a greenhouse pot study in response to soil type, phosphorus (P) amendment, and cowpea Rhizobium inoculation. Ninety days after transplanting seedlings into sandy loam, D. aurea yielded 65% more (P ≤ 0.05) herbage DMY than D. candida, 147% more than D. purpurea, and 248% more than D. multiflora. In the same sandy loam, Dalea candida produced 196% greater (P ≤ 0.05) root DMY than D. aurea, which yielded the least. Dalea aurea had 61% greater (P ≤ 0.05) herbage N content than D. purpurea, which contained the least. Dalea aurea yielded 107% more (P ≤ 0.05) herbage N DMY than D. candida, 338% more than D. multiflora, and 375% more than D. purpurea herbage N DMY. All Dalea spp. produced as much or more (P ≤ 0.05) herbage and root DMY in sandy (pH 5.6) and sandy loam (pH 7.1) soils as they did in limestone clay (pH 8.2). Plants growing in high moisture-retaining potting soil performed poorly. Inoculation with commercial cowpea rhizobia and amending soils with P had either no (P > 0.05) or negative (P ≤ 0.05) effects on development. Dalea multiflora had the most biologically active phenols while D. aurea and D. candida had none.

Girgin G, Muir JP, Jessup RW, Schwab AP. 2020. Dalea aurea, D. candida, D. multiflora, and D. purpurea seedling herbage, root nitrogen, and dry matter yield as influenced by soil type, phosphorus amendment, and cowpea Rhizobium inoculant. Native Plants Journal 21(3): 341–351.