Study On The Growth And Development Of Different Leaf Number Flue-cured Tobacco Varieties

Pot experiment was conducted to study on the different leaf number flue-cured tobacco varieties of Bi Na-1,Nan Jiang-3,and K326.The law of thier growth focus on growth rule of the main growing period,main agronomic traits,dry matter accumulation and distribution,the content of N,P,K accumulation;development rule mainly studied on flower-bud differentiation procedure.The main results are as follows:1.Bi Na-1,Nan Jiang-3,K326 enter the rosette stage after transplanting 25 d,31d,27 d respectively;The initiation period of flower bud differentiation were compared with that of the rosette stage late 9d,late 3d,advance 4d;transplanting to the budding lasted 66 d,68d,52 d respectively;transplanting to the flowing lasted 72 d,74d,61 d.2.After transplanting 30d～70d,the height of tobacco growth rate first increased then decreased;The maximum growth rate of Bi Na-1,Nan Jiang-3,K326 appeared on transplanted 50d～60d,50d～60d,40d～50d respectively.Stem girth growth first drop and then decline after the rise,The maximum growth rate of Bi Na-1,Nan Jiang-3,K326 appeared on transplanted 30d～40d、50d～60d、30d～40d respectively.The leaf growth rate of Bi Na-1was first slow then quick and finally slow down again;the maximum rate appeared on transplanted 40d～50d,the natural leaf number was 41.0pieces per plant.The leaf growth rate of Nan Jiang-3,K326 continued to decline,the maximum rate appeared on transplanted 30d～40d,the natural leaf number of Nan Jiang-3 was 37.4 pieces per plant,and K326 was 36.4 pieces per plant.The growth rate of maximum leaf area of Bi Na-1,K326,they all first decreased then increased,the maximum rate appeared on transplanted 60d～70d;however,Nan Jiang-3 was first slow,then quick and finally slow down again,the maximum rate appeared on transplanted 50d～60d.3.The results showed that the law of dry matter accumulation amounts;N,P,K accumulation amounts in different organs and the whole plant of different tobacco varieties were “slow-quick-sloow”;there were no difference in different tobacco varieties,but each stage the accumulation rate was different because of the tobacco varieties.After transplanting 30d～70d,the dry matter accumulation amounts were first increased then decreased,the maximum rate of root was after transplanting40d～50d;the maximum rate of stem,leaf and whole plant were after transplanting50d～60d.In different tobacco varieties,organs;the dry matter distribution amounts ratio was leaf >stem>root,the leaf distribution ratio was more than the sum amounts stem and root.Early stage of growth and development of tobacco,the proportion of dry matter accumulation in leaves was higher than others.With the growth and development,the relative distribution of dry matter accumulation of root and stem increased gradually,and the relative distribution of leaf decreased.After transplanting 30d～70d,the different leaf number flue-cured tobacco varieties of root,N accumulation rate was an additional increasing after the first drop,and the maximum rate was after transplanting 40d～50d;P accumulation rate was first increaed then decreased,and the maximum rate was after transplanting 40d～50d;K accumulation rate was continued to decline,and the maximum rate was after transplanting 30d～40d.In stem,N accumulation rate was first increased then decreased,and the maximum rate was after transplanting 50d～60d;P accumulation rate was first increased then decreased,and the maximum rate was after transplanting40d～50d;K accumulation rate was first slow,then quick and finally slow down again,and the maximum rate was after transplanting 50d～60d.The leaf and whole plant,N,P,K ccumulation rate were first increased then decreased,the maximum rate was the same as stem.The N,P,K ccumulation rate of different leaf number flue-cured tobacco varieties were characterized by leaf>stem>root,the accumulation rate of leaf was higher than the sum of stem and root;the accumulation were characterized by K>N>P,the accumulation of N was more than the sum of N and K.3.The development process of flue-cured tobacco flower bud differentiation was divided into two phases,and the two phases were divided into eight stages.The firstphase was named Flower bud formation stage,this phase include four period:the first bract leaf primordium differentiation stage,the first inflorescence primordia differentiation stage,the second inflorescence primordia differentiation stage,pistil and stamen primordium differentiation stage;The second phase was named developent stage of pollen,this stage include four stages: pollen mother cell formation stage,tetrad formation stage,Single cell pollen formation stage,Two-cell pollen formation stage(pollen maturation stage).There is no obvious difference of flower bud differentiation in morphology among Bi Na-1,Nan Jiang-3,K326.Bi Na-1,Nan Jiang-3,K326 the flower bud differentiation whole process lasted24 d,22d,28 d respectively;Flower bud formation stage lasted 13d～15d,11d～13d,13d～20d respectively;development stage of pollen lasted9d～11d,9d～11d,8d～15d respectively.