Soil water availability in lily bulbs production.

MARINANGELI PABLO; FACCHINETTI, CECILIA; CURVETTO, NÉSTOR

Pescia

Simposio; 2nd International Symposium on Genus Lilium; 2010

International Society for Horticultural Science

Complementary surface, overhead or drip irrigation are used in the production of lily bulbs, with scarce information on their efficiency. Frequency of irrigation allows the decrease of soil water availability (SWA) at different levels before a new watering. This work studied the effect of lower SWA limits in the root zone on the production of bulbs of Lilium in Bahia Blanca (38º 40´ S, 62º 14´ W), Argentina, on a sandy-loam soil with 1.6% organic matter. Two bulb sizes: scaling, bulbs attached to the mother scales, and yearling, one year old bulbs (size: 6-8 cm circumference), and from two hybrids of L. longiflorum White Heaven and Asiatic Navona, were evaluated. Three watering treatments with a lower limit of SWA of -0.15, -0.25 and -0.40 bar at 10-15 cm depth were applied during two growing seasons, from July to March. Leaf relative water content resulted high in the three treatments in both hybrids (84 to 91%), as under water stress plants closed the stomata. So, when SWA was -0.25 or -0.40 bar it affected significantly (p < 0.05) the biomass and the size of the bulbs at harvest with respect to -0.15 bar; with the maximum decrease in biomass in ‘Navona’ (p < 0.05). For the soil and climatic conditions of Bahía Blanca, the yield of both hybrids was affected by a slight temporary water deficiency, despite it was within the range of available water. The application of high-frequency irrigation systems are recommended in order to allow the first 15 cm of soil to be permanently at the required water availability.