栽培密度对橡胶草生长和产量的影响

Effects of Plant Densities on Growth and Yield of Taraxacum kok-saghyz

橡胶草作为可替代橡胶树的优良天然橡胶资源之一,前景可见,为了促进橡胶草的应用,采用田间单因素试验设计,以俄罗斯的橡胶草优良品系K445为试验材料,分别研究了栽培密度15cm×15cm、20cm×20cm、25cm×25cm、30cm×30cm、35cm×35cm对一年生橡胶草地上与地下部位的影响。结果表明:当栽培密度为25cm×25cm时地上生物量最高。栽培密度也会显著影响橡胶草的橡胶含量,当栽培密度为20cm×20cm及35cm×35cm时,橡胶含量最大,达到了6.0%以上。单株地下生物量会随着栽培密度的减少而增加,最高达到8.9g,而当栽培密度大于20cm×20cm时单位面积地下生物量不再增加,最高为152.2g·m^(-2)。当栽培密度为30cm×30cm时总糖含量最高,为46.8%。总糖产量与单位面积地下生物量表现一致,最高为64.8g·m^(-2)。当栽培密度为20cm×20cm时,橡胶草单位面积橡胶产量最高,达到了9.4g·m^(-2),而当栽培密度为35cm×35cm时,橡胶草平均单株橡胶产量最高,为535.3mg。根叶比随着栽培密度的减小而增大,此时更多的生物量分配到地下部位。所以栽培密度35cm×35cm适合于橡胶草选种育种,而栽培密度20cm×20cm适合于橡胶草大面积生产。

R ussian dandelion is one of the m ost prom ising natural rubber resources which may take the place of rubber tree,h as a brhght future.Effects of plant densities(15cm×15c m,20cm×20c m,25cm×25c m,30cm×30c m,35cm×35cm)on grow th of aboveground and underground parts and yield of Russian dandelion were analyzed by applying single-factor experim ental design in a field and using elite cutivar-K445introduced from Russia,the results showed that aboveground biom ass was the highest when plant density for25cm×25cm.Plant densities also affected rubber concent of R ussian dandelion significantly.And rubber concent w ould get above6.0%when plant densities for20cm×20cm as well as35cm×35cm.U nderground biom ass per plant increased w ith the decrease of plant density,and the highest reached8.9g.W hile underground biom ass per unit area would not increase any m ore when plant density was over20cm×20cm when it was152.2g.m-2.When plant density was30cm×30cm,to tal sugar concent reached the highest point,nam ely46.83%.T otal sugar yield show ed the same trend as underground biom ass per unit area,th e highest being64.83g.m2.W hen plant density was20cm×20cm,rubber yield per unit area got the highest point,nam ely9.4g.m2.W hile plant density was35cm×35cm,average rubber yield per plant was the highest,nam ely535.3mg.R ratio of root to leaf increased w ith the decrease of plant density,when m ore biom ass w ere allocated to underground parts.Therefo re,p lan t d en sity,35cm×35cm,is suitable for selection and breeding of R ussian dandelion,w hile plant density,20cm×20cm,is suitable for industrial production.