DefinePK

Abstract

The coastal area of Thanh Hoa province has a large proportion of sandy soils, about 24% of the natural land; this is a group of land with poor water and nutrition holding capacity. Studies show that biochar can improve soil environment, improve soil production through reducing acidity, increasing cation exchange capacity, increasing water and nutrient holding capacity. In addition, with advances in plant varieties, in Vietnam, hybrid varieties of maize with drought, cold tolerance, and good productivity and quality have been developed. This study conducted two factors: the amount of biochar applied and the drought tolerant maize varieties to evaluate the effects of biochar as well as the maize varieties in the dry sandy soil condition in coastal areas of Thanh Hoa province. Research results show that, when applying biochar at 5 tons / ha, the yield of maize varieties reaches the highest and is equivalent to applying 10 tons of manure. As such, biochar can replace manure used in maize cultivation in the study area. Experimental results of three drought tolerant maize varieties showed that, with the amount biochar applied was 5 tons / ha, the variety LVN061 has higher actual productivity than the two varieties of LVN092 and LVN17. For LVN061 maize variety, the level of fertilizing 10 tons of manure, 5 tons of biochar and 6 tons of biochar achieved the highest productivity and were similar at the 95% confidence level. With biochar applied at 5 tons / ha, the maize varieties actual productivity more than 6 tons / ha, higher than the current average maize actual productivity in the study area (below 6 tons / ha). The economically optimal amount of biochar applied for the three maize varieties LVN092, LVN17 and LVN061 were 4.98 tons / ha, 4.81 tons / ha and 4.65 tons / ha respectively. This is the amount of fertilizing for high economic efficiency as well as ensuring nutrition supply for growing maize.