Effects of TerraCottem and High Water-Absorbing Polymer on Growth and Drought Endurance of Tree Seedlings

Abstract

Effects of three soil conditioners: TerraCottem (TC), high water-abosorbing polymer (HWAP) in the form of polyacrylamide and husk ash on growth and drought endurance of seedlings of narra, eucalyptus, Kaew and Khiew Sawauy mango were studied in pots under naturally-lit glasshouse at Si Sa Ket Horticultural Research Center, Sisaket province.rnResults showed that uses of TC, HWAP and husk ash as soil conditioners significantly affected physical properties of Korat soil. Plant available water of the soil incroporated with all three soil conditioners was increased of which, the soil incorporated with HWAP had the highest plant available water. Saturated hydraulic conductivity of the soil incorporated with TC of HWAP was decreased by fifty percents. With respect to soil chemical properties, all soil conditioners slightly affected electrical conductivity and reaction of the soil. The soil incorporated with TC and husk ash had more macronutrients (N,P,K, Ca and Mg) than the original soil whereas the soil mixed with HWAP had only greater nitrogen content.rnUses of TC, HWAP and husk ash increased plant available water of soil, leading to an increase in plant growth. Grafted seedlings of Khiew Sawauy mango showed more prominent response than narra, cucalyptus and Kaew mango seed-grown. Concerning the drought endurance of the plants, result showed that under unwatered condition, Kaew mango could survive the longest and the runners-up were narra, eucalytus and Khiew Sawauy respectively. Effect of soil conditioners on time to wilting of these seedlings under watered condition, TC showed the best prolongation of plant life.