结构优化对铜仁上部烟叶产质量的影响

Effect of structural optimization on yield and quality of tobacco upper leaf in Tongren

通过利用不同打顶时期与留叶数互作对烤烟农艺性状、经济性状的影响,改善烟株个体发育和群体结构,构建合理株型,提高上部烟叶产质量,进而提高铜仁烤烟上部烟叶质量和工业可用性,为铜仁优质烤烟上部烟叶生产提供理论依据。通过大田试验,采用二因素三水平随机区组设计,二因素为打顶时期和留叶数,打顶时期记为A,三水平为现蕾期(A1)、初花期(A2)、盛花期(A3),留叶数记为B,三水平为18片(B1)、20片(B2)、22片(B3),每处理3次重复。结果表明:在同一打顶时期,随着留叶数的增加,最大叶面积、顶叶面积和倒三叶面积均呈先增加后减小的趋势;打顶时期对烤烟经济性状影响较小,而随着留叶数的增加,烤后烟产量、均价、产值及上等烟比例均逐步减少,中上等烟比例以A2B2和A2B1处理较高,其值分别是98.63%和98.55%;现蕾期打顶并留叶20片,烤后烟叶外观质量和感官质量得分最高,分别为7.38和69.10分;随着留叶数的增加,在现蕾期打顶,总糖含量、还原糖含量、糖碱比和钾氯比等指标均呈先增加后减小的趋势,烟碱、总氮、钾、氯含量等均呈先减小后增加的趋势,而两糖比逐渐减小;在初花期打顶,总糖、还原糖含量逐渐降低,烟碱、总氮含量及钾氯比先降低后升高,钾含量、氯含量、两糖比等指标逐渐升高,而糖碱比先升高后降低;在盛花期打顶,总糖、还原糖、总氮含量和糖碱比等先升高后降低,烟碱含量和钾氯比呈先降低后升高,钾含量和两糖比逐渐升高。综合而言,现蕾期打顶并留叶20片可改善烟株农艺性状,提高烟叶外观质量和感官质量,化学成分含量适宜且协调性较好,经济性状相对较好,可在铜仁烟区示范推广应用。

Through the effects of different topping stage and remained leaf number on agronomic and economic traits of flue-cured tobacco,the individual development and population structure of tobacco plants were improved,reasonable plant type was established,and the yield and quality of upper tobacco leaves was improved,and then the quality and industrial availability of upper tobacco leaves of Tongren flue-cured tobacco were improved,providing a theoretical basis for the high-quality production of upper tobacco leaves of Tongren.Through the field experiment,a two-factor and three-level random block design was adopted.The two factors were topping stage and remained leaf number,the topping stage was recorded as A;the three levels were bud stage(A1),initial flowering stage(A2) and full flowering stage(A3),the remained leaf number was recorded as B;the three levels were 18 pieces(B1),20 pieces(B2) and 22 pieces(B3),and each treatment was repeated 3 times.The results showed that the maximum leaf area,the area of the uppermost leaf area and the area of the third leaf from the top increased first and then decreased with the increase of the remained leaf number in the same topping stage.The topping stage had little effect on the economic properties of flue-cured tobacco,but with the increase of the remained leaf number,the yield,average price,output value and proportion of high-grade tobacco gradually decreased,and the proportion of medium and high-grade tobacco was higher under A2B2 and A2B1 treatment,which were 98.63% and 98.55%,respectively.The appearance quality and sensory quality scores of cured tobacco leaves were the highest,7.38 and 69.10 points,respectively.With the increase of the remained leaf number,the indices of total sugar content,reducing sugar content,sugar-base ratio and potassium-chlorine ratio all increased first and then decreased at the peak of bud stage,while the nicotinic,total nitrogen,potassium and chlorine all decreased first and then increased,and the ratio of two sugar gradually decreased.At the peak of early flowering,the contents of total sugar and reducing sugar gradually decreased,the contents of nicotine and total nitrogen and the ratio of potassium to chlorine first decreased and then increased,the ratio of potassium,chlorine and the ratio of two sugar gradually increased,and the ratio of sugar-nicotine first increased and then decreased.At the peak of flowering stage,the content of total sugar,reducing sugar,total nitrogen and the ratio of sugar-nicotine increased first and then decreased,the content of nicotine and the ratio of potassium to chlorine decreased first and then increased,and the content of potassium and the ratio of two sugar gradually increased.All in all,topping and leaving 20 leaves at the bud stage can improve the agronomic traits of tobacco plants,improve the appearance quality and sensory quality of tobacco leaves,the chemical composition content is suitable and the coordination is better,and the economic properties are relatively good,which can be demonstrated and applied in Tongren tobacco-growing area.