不同基因型烟草根系分泌物对难溶性磷钾的活化效应

Activated Effect of Root Secretions in the Different Genotype Tobacco to Difficult Dissolving Phosphorus and Potassium

为探明烟草根系分泌物对不同形态磷、钾矿物的活化能力,通过水培实验,证实正常条件下生长的烟草具有活化磷、钾矿物的能力,但基因型间的差异较小.在缺磷、钾的胁迫条件下根系分泌物的活化能力得到提高,基因型间的差异增大,香料烟(沙姆逊)根系分泌物的活化能力最强,白肋烟(白肋21)次之,烤烟(NC89)较弱;根系分泌物作用于磷、钾矿物2h后,活化能力达到最大值,并随温度的提高而逐步增强.烟草根际分泌物对云母矿物钾的活化能力大于钾长石;而对Ca-P的活化能力较低,对Al-P的活化能力较强,对Fe-P活化能力次之.pH对活化各类磷矿物的影响较大,当pH5时活化Fe-P,Ca-P的能力要高于pH9,这种现象在缺磷胁迫条件下更为明显,pH对Al-P活化作用的影响有所不同.

In order to research activating ability in root secretions of tobacco to different forms of phosphorus and potassium mineral,this text confirms by experimenting on water culture that tobacco under normal condition possesses the ability of activating phosphorus and potassium mineral,but difference between genotypse is smaller.Activating ability in root secretions gets enhancement under the condition of phosphorus and potassium deficiency.Difference between genotypes is enlarged.Activating ability in root secretions of oriental tobacco(Samsun) is the strongest,burley tobacco(burley 21) the secondary,while the flue-cured tobacco ( NC89 ) is weaker.After 2 hr from root secretions acting on phosphorus and potassium mineral,activating ability achieves largest,and strengthen step by step along with raising of temperature.Activating ability in root secretions of tobacco to mica mineral potassium is greater than the potassium feldspar.Activation energy to Ca-P is lower,to Al-P is stronger,and to Fe-P is secondary.The influence of pH to activate various phosphorus minerals is bigger.The activating ability of Fe-P in pH=5 and Ca-P is more than pH=9,and this phenomenon is much clear under the condition of phosphorus deficiency,but it is different to Al-P’s activating effect.