Effect Of Soluble Silicon Fertilizer On Growth And Quality Of Flue-cured Tobacco

Schemes of single factor test was carried out in science-technology demonstration park in baofeng in Henan in 2015.The experiment set up 4 treatments:T1 treatment with Silicon application of 25kg/667m2;T2 treatment with Silicon application of 50kg/667m2;T3 treatment with Silicon application of 75kg/667m2;CK treatment with no Silicon fertilizer,in order to study the effect of different Si application treatments on tobacco growth,physiological characteristics,chemical components,plastid pigment,antioxidant enzyme activity,and neutral aroma components in flue-cured tobacco,thus providing theoretical foundation for high-quality tobacco leaf production in local area.The main results were as follows:1.Si application increased agronomic characteristic indexes of flue-cured tobacco to varying degrees.The effect of T2 and T3 treatment was the best,showing that Si application could promote tobacco growth.Si application increased the physiological characteristics of tobacco leaves including leaf length,single leaf weight,filling value and tensile strength,and decreased stem ratio.The effect of T2 and T3 treatment was the best in leaf length,single leaf weight,filling value and tensile strength.2.In field period,the total nitrogen content rose slowly in early stage,declined rapidly in 75 th day and kept stable in 90 th day.Si application could postpone carbon and nitrogen metabolism.In 90 th day,total nitrogen content of T3 and CK treatment was higher than of T1 and T2 treatment.The chlorine content rose slowly in early stage,increased rapidly in 75 th day.And then,Si application treatments decreased the chlorine content significantly compared with CK treatment.The nocotine content rose slowly in early stage,then rose rapidly and reached the maximum in 90 th day.The potassium content rose slowly in the 30 th,45th day,declined in the 60 th,75th day and rose slowly in 90 th day.In the 90 th day,,the fixed sample's potassium content of T1?T2?T3 treatment wa increased by 0.14%,0.25%,0.15% respectly,compared with CK treatment.Si application could promote potassium content and improve the quality of tobacco leaf.3.The reducing sugar,total sugar and possium content was ignificantly increased in middle and upper leaves.The chlorine content was ignificantly decreased in middle and upper leaves.Sugar-nicotine rotio,Sugar-nitrogen rotio and potassium-chlorine ratio was more harmonious.Si application could increased reducing sugar,total sugar,possium content,declined the chlorine content significantly in middle and upper leaves and harmonize chemical components.4.The chlorophyll content of defferent Si treatments was lower than of CK treatment in the 30 th day,and increased slowly,reaching maximum in the 60 th day.Then the chlorophyll content of different treatments showed the tendency of decline in mature stage.The chlorophyll content of CK treatment reached the maximum of1.70 mg·g-1in the 45 th day.And the chlorophyll content of T1,T2 and T3 treatment reached the maximum of 1.68 mg·g-1?1.91 mg·g-1?1.57 mg·g-1 respectively in the 60 th day,higher than CK by 15.07%,30.82% and 7.53% respectively.Si application could postpone chlorophyll content peak and promote the chlorophyll content.The carotenoid content increased slowly in the first 70 days,and declined in the 90 th day.The carotenoid content of T2 and T3 treatment was significantly increased in the 90 th day.Si application could significantly promote the carotenoid content.5.SOD activity of different Si treatments was higher than CK treatment.And SOD activity of T2 treatment was the highest,32.93% higher than CK treatment.In field stage,POD activity showed the tendency of increasing.Si application significantly increased POD activity.Thus Si application could ease membrane lipid peroxidation,providing theoretical foundation for disease resistance of tobacco.6.Si application significantly increased maillard reaction products,carotenoid content,phenylalanine content,cembranoids content,neophytadiene content and neutral aroma component amount,compared with CK treatment.T3 treatment's aroma component content was less than other Si fertilizer treatments in upper leaf,and this could be because that high concentration Si improved the growth and delayed carbon and nitrogen metabolism.In total,Si application could promote aroma component.And the effect of T2 treatment(50 kg/667 m2)was the best.7.Appearance quality of different Si treatment was better than CK treatment.The score of appearance quality was that T2>T1>T3>CK.And T2 treatment's score was the highest with orange colour,better maturity,loose structure,medium weight,more oil content and strong chroma.And T2 treatment's score was was the highest in smoking quality as high as 78.58 with medium aroma quality,enougharoma amount,lesser offensive odor,comfortable remaining taste,grey colour,fresh and medium flavor,medium clustering ability,medium dryness and medium soft type.And T2 treatment's score was higher than CK treatment in each smoking index and sensory quality.Thus Si application could promote tobacco leaf quality to some extent.