Effect of fertility ratios on growth and turf quality of perennial ryegrass(Lolium prenneL.) in winter

Abstract

Perennial ryegrass (Lolium prenne L.) has been introduced to Japan as a cool season turfgrass. In spite of relatively mild winter in most parts of the country, it still goes to winter dormancy. A well-balanced fertility ratio and rate may prevent such dormancy without causing winter injury. Therefore, this experiment was designed to find a balanced rate and ratio among nitrogen (N), potassium (K), and phosphorus (P) fertilizers in order to prevent winter dormancy and promote growth during the winter in Japan. Yorktown 2 perennial ryegrass was used in this experiment. Nitrogen and K application rates were 50,150,250, 350, 450, 550, and 650 kg K/ha; whereas P rates were 50, 150, and 250 kg P/ha. These rates were applied in 30 different ratios. Growth, color, and density of the turf were estimated and used as the parameters for finding a suitable rate and ratio for these three major nutrients. Color, density, and growth were increased as the rate of N fertilizer increased, but there was no visual response to P or K rates. It is suggested that increases in color, density, and growth were function of N rates, whereas K and P rates maintained the cold hardiness of the turf when high N rates were applied under the conditions of this experiment. Fertility ratio and the rates of 450 kg N/ha, 250 kg K/ha, and 50 kg P/ha were sufficient to prevent dormancy, promote growth, and produce good quality turf throughout the winter. Thus, it is concluded that fertility ratios and rates are the main factors limiting growth and quality of perennial ryegrass in transitional zones similar to Japan.

Quantitative and qualitative responses of an established Kentucky bluegrass (Poa pratensis L.) turf to N, P, and K additions

“…Johnson et al (1987) found that N increased bermudagrass shoot density with greatest responses using 100 and 200 kg N ha -1 yr -1 while 200 kg N ha -1 yr -1 was adequate to properly maintain lawns in the Piedmont region of Georgia. Foliage colour rating improved with N rates of 50 to 650 kg N ha -1 in perennial ryegrass (Razmjoo and Kaneko 1993). Close relationships were found between fresh clipping weight and foliage colour rating of Kentucky bluegrass (Hummel and Waddington 1981), hence, quantitative turfgrass attributes could corroborate aesthetic evaluations.…”

“…Christians (2004) explained that turfgrass has fibrous multi-branched root systems that make them relatively efficient at obtaining P from the soil. Even in soils that tested low to very low in P, little or no clipping yield response has been observed by Walker et al (1963), Waddington et al (1978), Turner (1980), Razmjoo and Kaneko (1993).…”

“…Additions of 50 to 350 kg P ha -1 yr -1 had no effect on turfgrass shoot density or foliage colour (Waddington et al 1978;Razmjoo and Kaneko 1993). observed no improvement on shoot density and foliage colour from using more than 49 compared to 98 and 196 kg K ha -1 yr -1 .…”

“…Many studies showed increased turfgrass foliage colour with increased N rates (Waddington et al 1972;Hummel and Waddington 1981;Razmjoo and Kaneko 1993). Rates of N to achieve given foliage colour ratings can be interpolated using the equations of Fig.…”

“…A high N availability in soil-turfgrass systems stimulates shoot growth (Turner and Hummel 1992) and yields high amounts of clippings (Walker et al 1963;Hull and Smith 1974;Hummel and Waddington 1981). There were significant increases in turfgrass shoot growth with ranges of 0 to 650 kg N ha -1 yr -1 (Walker et al 1963;Juska and Hanson 1967;Hull and Smith 1974;Razmjoo and Kaneko 1993), and 12 to 98 kg N ha -1 mo -1 (Trenholm et al 1998). Nitrogen also had a large effect on turfgrass shoot density and foliage colour ratings (Hummel and Waddington 1981).…”