Effect of Rice Husk Biochar on Soil Nutrients of Tobacco Field, Yield and Quality of Tobacco Leaves in Land Consolidation Areas

In order to explore the effects of biochar on soil improvement, yield and quality of tobacco leaves in land consolidation areas, we conducted field experiments in the tobacco planting area of south Anhui Province, to study the influence of different amounts of rice husk biochar on soil nutrients, yield and quality of tobacco leaves. The results showed that rice husk biochar application could decrease soil bulk density, improve soil pH, and increase the soil organic matter, alkali-hydrolyzable nitrogen, available phosphorus and available potassium content. The results also showed that rice husk biochar application could promote the growth of tobacco and influence the appearance characters of tobacco leaves, especially the oil content of tobacco, which decreased with the increased amount of biochar application. The contents of total sugar and reducing sugar in flue-cured tobacco leaves decreased, but the total nitrogen, nicotine and potassium contents increased with the dosage of rice husk biochar in a certain degree. The coordination of tobacco chemical composition in T2 treatment(7.5 t/ha of biochar)was better than that in other treatments. Meanwhile, the sensory quality of tobacco leaf increased or remained the same at first, then decreased with the increasing amount of biochar application, the order of sensory quality of tobacco leaf in all treatments was T1=CK>T2>T3. The yield and output value of flue-cured tobacco both increased with the amount of rice husk biochar. The highest yield(1729.2 kg/ha)and output value (37516.8 Yuan/ha)were found inT3 treatment, which increased by 43.51% and 43.48% respectively compared with those in CK. However, the high-class-leaf percentage of flue cured tobacco increased firstly, then decreased with the increasing amount of biochar application. Based on the comprehensive influence of rice husk biochar on soil nutrients, the yield and quality of tobacco leaves, the amount of rice husk biochar application should be no more than 7.5 t/ha in land consolidation tobacco fields of south Anhui.