EFFECT OF IRRIGATION AND NITROGEN LEVELS ON PLANT CHARACTERISTICS IN PERENNIAL RYEGRASS


DEMİREL K.

FRESENIUS ENVIRONMENTAL BULLETIN, cilt.23, ss.1971-1978, 2014 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 23
  • Basım Tarihi: 2014
  • Dergi Adı: FRESENIUS ENVIRONMENTAL BULLETIN
  • Sayfa Sayıları: ss.1971-1978

Özet

This study investigated the effects of varying irrigation and nitrogen levels on perennial ryegrass (Lolium perenne L. cv. 'Caddyshack') taking into account water consumption, visual quality, leaf water content and fresh and dry clipping yield. Additionally, results were simulated with HYDRUS/1D by using water contents measured by sensors, climate and soil properties data. The pot experiment was conducted under field conditions in 2012. Three different irrigation treatments were investigated (soil moisture in pot completed to 100%, 75%, 50% of the soil water-holding capacity) in conjunction with three different nitrogen (N) applications (284 g N per pot, 142 g N per pot, no nitrogen). Results showed best visual quality was obtained with 142 and 284 g N per pot. Seasonal evapotranspiration values for all treatments varied between 367 and 547 mm per season. Total fresh and dry clipping yields were found to be 10.2-56.4 g per pot and 2.1-13.4 g per pot, respectively. Water use efficiency and irrigation water use efficiency were calculated as 0.36-1.69 kg m(-3) and 0.44-2.07 kg m(-3), respectively. Correlation coefficients between measured soil water contents and predicted (HYDRUS/1D) values were between 0.82-0.95. None of the treatments except for "no nitrogen" applications were not affected by amount of irrigation water in terms of visual characteristics and irrigation water was found to be sufficient to sustain acceptable turfgrass quality under semi-arid conditions. It is advised that a 50% water deficit and 284 g N per pot (40 kg ha(-1)) be used to achieve the desired quality of turfgrass.