Soil Improvement And Potassium Accumulation Of Tobacco Using Bio-organic Fertilizer

Chronic indiscriminate use of pesticides and inorganic fertilizers，the increasingpollution of environment has caused problems in recent years. The problems includingreduction of crop quality, emergence of soil harden and drought, agricultural pests andpathogens increase, and depletion and diminution in bio-availability of soil nutrients.In this study, we use Phanerochaete chrysosporium (P. chrysosporium) andBacillus thuringiensis (B. thuringiensis) as benefic ial additives to the decomposedrapeseed cake. To test the effect of the bio-organic fertilizers on potassium contents ofsoil and plant, soil invertase enzymes activity of soil, defensive enzymes activity ofplant leaves by P. chrysosporium and B. thuringiensis, the field experiment wasconducted in the village Longfu in Liuyang City of Hunan Province.The bio-organic fertilizer can significantly increase the content of soil totalpotassium and available potassium. In addition, the highest releasing power wasobserved at growth stages of30d, the application of bio-organic fertilizer treatmentssignificantly increased available potassium concentrations in soil from0.738g/kg(control) to1.024g/kg (BOF1),0.978g/kg (BOF2) and0.902g/kg (BOF3)respectively. These increases reached to more than38%,32%and22%respectively.The total potassium content of soil under bio-organic fertilizers was significant higherthan the control in the early stage of the tobacco.Bio-organic fertilizer treatments can generally enhance the soil invertase enzymeactivity. The highest increase achieved20%compared to organic fertilizer. Theincrease was greater in both addition of P. chrysosporium and B. thuringiensis thanthat alone, and B. thuringiensis gave a more promote effect than P. chrysosporium.It is clear that the concentration of potassium in stems and roots of tobacco hadsignificantly increased as a result of bio-organic treatments. The concentration wasincreased by14.2%,13.8%and5.5%in stems at69d and by55.4%,48.6%and30%in lateral root at57d and by146.3%,98.8%and76.8%in taproot at57d by theapplication of BOF1, BOF2and BOF3respective ly. The bio-organic treatments affectan increase of potassium content to a maximum of30%in tobacco leaves comparedwith the control. BOF1treatment is the best choice to enhance the potassium contentof different positions in tobacco. The activities of catalase, peroxidase and polyphenoloxidase in plant leaves weresignificantly higher in the bio-organic fertilizer treatments than the control. Theaugmentations of BOF1treatment on the catalase activities were the highest in themiddle leaves (25~31%), followed by upper leaves (5~35%) and lower leaves (4~25%)compared to the activities present in the control treatment. The peroxidase enzymeactivity of the bio-organic fertilizer treatments was higher than in the controltreatment，and different parts of the leaves were enhanced at different levels:10–30%of upper leaves,11–13%of middle leaves and10–30%of lower leaves by the BOF1treatment compared with the control treatment. Compared with the control treatment,the activity of polyphenoloxidase under BOF1treatment achieved its maximumincrease in middle leaves (140–200%), followed by the upper leaves (8–38%), withthe minimum increase found in the lower leaves (5–25%).The experiment can promote the spread use of the bio-organic fertilizer, and canprovide a theoretical basis of P. chrysosporium and B. thuringiensis have the potentialto improve soil and plant quality.