Yield and Nutrient Accumulation of Tifway Bermudagrass and Overseeded Ryegrass as Influenced by Applied Nutrients1
- J. B. Sartain and
- A. E. Dudeck2
This study was initiated to evaluate the effect of N fertilization rate on the P, K, and Mg requirements of ryegrass (Lolium perenne L.) and bermudagrass (Cynodon dactylon (L.) Pers. X Cynodon transvaalensis Burtt Davy) and to determine the N fertilization requirements of the two turfgrasses. Information gained through this research will be of particular benefit to producers of cool and warmseason turfgrasses on golf courses of the southeastern USA. During the fall ‘Medalist 11’ (a mixture of Pennfine and NKl00 cultivars) perennial ryegrass was seeded over ‘Tifway’ bermudagrass growing on a loamy fine sand (Typic Quartzipsamment). Treatments were applied in a split-plot arrangement in plots 1.83 ✕ 2.73 m and replicated five times. Nitrogen was applied as ammonium nitrate at 2.5 g N/m2 every 1, 4, and 8 weeks to establish the rates of 20, 5 and 2.5 g N/m2/8 weeks, respectively. Four subplot treatments were applied every 12 weeks using 5, 10, and 5 g/m2 of P, K, and Mg, respectively, as a complete treatment. The three additional treatments were established by excluding one of the three nutrients, respectively. The turfgrasses were mowed at 3-day intervals. Harvests for yields occurred biweekly and consisted of 3-day growth of the grasses. Ten harvests were collected per grass species per growing period. The study extended over two growing periods for each grass species and a total of 40 harvests. The two lower N rates (2.5 and 5.0 g/m2/8 weeks) were not adequate to maintain acceptable turfgrass quality. A higher incidence of disease and a lower quality turf resulted from these treatments. Tifway bermudagrass had a higher dry matter yield rate than Medalist II ryegrass at a given N percentage and grew faster at each level of N applied. Ryegrass responded to P on this soil which contained a minimum of 82 ppm double-acid (0.025N H2SO4 in 0.05N HCl) extractable P. Contrarily, bermudagrass produced the highest yield when P was excluded. Both grasses were reduced in yield by exclusion of K at the high N rate. The minimum double-acid extractable K level was 33 ppm. Ryegrass accumulated more N, P, K and Mg at each level of N fertilization than bermudagrass. Excluding P tended to reduce the N percentage in ryegrass tissue, but increased the N percentage in bermudagrass. A level of 60 ppm double-acid extractable Mg was adequate for growth of both grasses even though the Ca:Mg ratio in some cases exceeded 20:l.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
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