Phosphate efflux rates from roots of Trifolium uniflorum, Trifolium repens and some T. repens x T. uniflorum interspecific hybrid clovers

Phosphate efflux rates from root systems were measured on hydroponically grown plants of Trifolium uniflorum, white clover (T. repens), and six interspecific T. repens × T. uniflorum clover hybrids that had been back-crossed to white clover. Efflux of phosphate was measurable for every clover type. There were only minor differences among the clovers for phosphate efflux g-1 root dry weight. Less than 0.6% of root phosphorus was lost over a four hour assay. It was concluded that selection of germplasm for variation in phosphate efflux rates is not likely to contribute to improving the phosphate efficiency of white clover.