Effects Of Infiltrating And Spray Irrigation On The Growth Of Centipedegrass And Creepevg Bentgrass

Infiltrating irrigation is a water-saving technique in agriculture. In order to apply the infiltrating irrigation on turfgrass, and its effects on turf establishment and turfgrass growth, as well as its related water-saving, we constructed a turf plot which was irrigated by infiltrating and spray irrigation system, respectively. Several studies were conducted for the effects of two irrigation systems and nitrogen levels on turf spring green-up, the effects of two irrigation systems and mowing heights on the turfgrass spring transition overseeded by perennial ryegrass in centipedegrass (latin name), effects of irrigation methods on the seed germination and turf establishment as well as turfgrass growth in creeping bentgrass (latin name). The results were as following:1. The experimental turf by underground infiltrating irrigation system runs smoothly. It was enough to provide the irrigation needs for centipedegrass. The turfgrass performed uniformly and well in all four seasons.2. Nitrogen fertilizers enhanced the spring green-up in centipedegrass turf. With the increase of N level, the turf quality, turf coverage, density, the growth of new buds and new leaves, and the shoot and root biomass increased accordingly. Compared with spray irrigation, infiltrating irrigation was more benefit to spring green-up. Turf quality under infiltrating irrigation was significantly higher than that under spray irrigation, and such difference was reduced with the increase of N fertilizers.3. Mowing was benefit to the turf transition trom perennial ryegrass to centipedegrass. After June 4th, the perennial ryegrass coverage ratio under 40 and 20 mm mowing heights was significantly lower than that without mowing. After May 21th, centipedegrass growth rate and biomass under infiltrating irrigation were significantly higher than that under spray irrigation in 40 mm mowing height, but such difference was not significant in 20 mm mowing height, indicating that 40 mm mowing height was more beneficial to centipedegrass growth and spring transition.4. Compared to spray irrigation, infiltrating irrigation caused the low moisture in top soil, which resulted the lower seed germination rate and seedlings. However, infiltrating irrigation increased the seedling growth speed of creeping bentgrass. By 30 d after sowing, tiller numbers under infiltrating irrigation was higher than that under spray irrigation, and by 40 d after sowing, the plant height and total leaves per plant were also higher than that under spray irrigation, which indicates that the higher seedling growth could took over its shortages in seed germination. No biomass difference was noticed after turf eatablished and infiltrating irrigation sould be used for creeping bentgrass establishment.5. Irrigated by 60% and lower field capacity significantly inhibited creeping bentgrass growth and decreased the turf quality. No significant difference in turf quality was observed under 80% of field capacity irrigation. The creeping bentgrass growth rate under infiltrating irrigation was significantly higher than that under spray irrigation after 24 d when irrigated lower than field capacity, as well as the green leaves, green/thatch ratio, and root biomass. When irrigated by field capacity or 80% of field capacity, no significant difference in water use efficiency was observed between two irrigation ways. However, when irrigated by 60% and lower field capacity, infiltrating irrigation showed significant higher water use efficiency and water saving effect than spray irrigation.