Effects Of Silicate Innoculant On Available Nutrient Contents In Soil And Yield Of Rice

Rice is one of the major crops and its growing area is increasing fast in recent years in northern cold region of China, however the information between microbial inoculants and nutrient content in soil as well as yield of rice is very limited in this region. The purpose of this experiment was to study the effects of microbial inoculants on nutrient content in soil and growth of rice in north cold region of China. The experiment was conducted using silicon bacteria as the microbial inoculants applied at the seedling transplanting time including four treatments, respectively:Silicate innoculant 0 kg/hm2(C0); Silicate innoculant 30 kg/hm2(C1); Silicate innoculant 60kg/hm2(C2); Silicate innoculant 120 kg/hm2(C3). With four replications in the field condition. The different microbe number, enzyme activities, available nutrient contents in soil, the nutrient contents, dry matter and yield of rice were measured in the experiment.The experimental results showed that during the growth of rice the application of silicate innoculant could change the number of soil microbes. The number of bacterium(except at the filling stage) and actinomycetes were significantly increased under treatments of C2 and C3, but the application of silicate innoculant reduced the number of fungus in the soil under treatments of C2 and C3 according to the data(except at the heading and maturation stages). Silicate innoculant could enhance the urease(except at the maturation stages) and sucrase(except at the tillering stages)activity in the soil within a certain range of dosage under treatments of C2 and C3. At maturation stage, the effect of application of silicate innoculant under on acid phosphatase activity was significant. The acid phosphatase activity under C2 and C3 treatments were increased by 37.8 %and 60.4 % than C0 respectively. Other stages were not significant.During the growth of rice, silicate innoculant could improve the contents of soil available silicon, alkali hydrolyzable nitrogen, available phosphorus and available potassium within a certain range of dosage. At maturation stage, applying silicate innoculant under C1 and C2 treatments increased the content of available silicon significantly in soil compared with treatment of C0. The content of available silicon in soil under C2 treatment was increased by 8.1 % than C0.In the tillering, heading and filling stages, silicate innoculant under C1 and C2 treatments made the content of alkali hydrolyzable nitrogen significant in the soil compared with C0. But in the maturation stage, the effect was not significant. Silicate innoculant of three treatments made the content of available phosphorus significant in the soil compared with C0. Except for tillering andheading stages, applying silicate innoculant of three treatments made soil available phosphorus content significant in the soil compared with C0 at other stages. During the growth period of rice,applying silicate innoculant of C1 and C2 treatments made the content of available silicon were significant higher than C0. Especially C2 treatment was obvious in the maturation stage.During the growth of rice, silicate innoculant could increase the whole contents of silicon,nitrogen, phosphorus and potassium within a certain range of dosage. During the growth of rice,silicate innoculant could promote rice to absorb silicon in the soil. The contents of silicon in the stem and leaf were significantly increased, and applying silicate innoculant of C2 and C3 treatments were very significant in the maturation stage. The contents of stem silicon under C2 and C3 treatments were 49.7 g/kg and 53.0 g/kg respectively. The contents of leaf silicon under C2 and C3 treatments were 82.6 g/kg and 84.5 g/kg respectively. In the filling stage and maturation stages,silicate innoculant could decrease the content of silicon in spike. During the growth of rice, silicate innoculant could improve the content of nitrogen in stems, leaves and spike. In the tillering stage,the effect of C2 treatment was particularly significant. In the tillering and heading stages, silicate innoculant of C2 treatment could improve the content of phosphorus in stems, leaves and spike.During the growth of rice, silicate innoculant could improve the content of potassium in stems,leaves and spike. In the heading and maturation stages, applying silicate innoculant of C2 treatment was significant.Silicate innoculant could increase dry matter weight of rice, rice filled grain number, effective tiller numbers and seed setting rate within a certain range of dosage, and increase the yield of rice.In each treatment, applying silicate innoculant of C2 treatment was significant, and rice yield was10878 kg/hm2.The pure income of rice was 6128 yuan/hm2.The application amount of silicate innoculant was 60 kg/hm2(C2) under the condition of cold temperate zone in the north of China. The effect of rice and soil was the best.