Effects of ebb and flow irrigation on soilless culture potted anthurium

In order to explore appropriate ebb and flow irrigation mode，effects of ebb and flow irrigation on soilless culture potted anthurium in multi-span greenhouse were investigated from July 4 to November 5 in 2009. Experimental mixed soilless culture with volumetric culture water capacity at 0.4315 and dry unit weight at 0.16 g/cm3 was composed of Danish PINDSTURP solid culture and Chinese perlite according to the volumetric proportion by 10:1. Experimental seedlings with 18cm height were planted in plastic pot with 1.4 L before experiment started. The depth of nutrition liquid was determined by the height of plastic pot(H) for ebb and flow irrigation treatments, with 1/2H for T1, 1/3H for T2, 1/4H for T3, and 1/5H for T4. T5 was drip irrigation, of which drip equipments were composed of on-line dripper with flow rate at 3.85 L/h, multi-outlet adaptors with 1/4 and flow-equalizer peg. All treatments had same low irrigating threshold with 80% substrate water capacity(θFC). The total ET, daily ET and culture moisture content were calculated by water balance method. The weight of experimental pots(pot, culture and seedling) and seedlings were determined by balance with 0.01g precision every day for pots and 5-7 d for seedling. Height and crown diameter were measured by ruler weekly. Results showed that irrigation technology has influence on culture moisture content, watering period, water consumption and flower quality. Total water consumption amount for one pot were 4337.6 g, 3926.7 g, 3780.2 g, 3695.9 g and 2562.3 g, average culture moisture content 98.5%θFC, 95.4%θFC, 90.4%θFC, 90.7%θFC and 84.7%θFC, maximal daily water consumption amount with one pot 52.3 g, 47.8 g, 46.8 g, 45.2 g and 33.6 g for T1, T2, T3, T4 and T5, respectively. Water use efficiency were above 90% for ebb and follow irrigation and 40%-50% for drip irrigation. Compared with drip irrigation, the substrate moisture content of ebb and flow irrigation was elevated 7%-23%, the watering period was prolonged for about 1-3 d, the amount of water consumption was advanced for 44.2%-69.3%, the height and crown diameter were elevated for 6.6-11.4 cm and 7.3-10.6 cm respectively, the length and width of spathe were elevated for 0.8-1.5 cm and 0.5-1.8 cm respectively, and the height of anthotaxy was elevated for 0.2-1.0 cm. Nutrition liquid depth is a key factor for water use efficiency and flower growth for ebb and flow irrigation. The substrate moisture content, watering period and growth of anthurium were not influenced by depth of nutrition liquid when the depth of nutrition liquid under or to be equal to 1/4H. The substrate moisture content would be elevated, watering period prolonged, and the amount of water consumption enhanced with the increase of nutrition liquid depth when the depth of nutrition liquid over 1/4H. T4 got the best quality of anthurium when the depth of nutrition liquid was 2.56 cm and watering period was 3-5 d. Further study would be focused on the mechanism about water holding and losing of soilless culture, effects of interaction for irrigation water amount and fertilizer amount on typical soilless culture flower.