Studies On Seasonal Dynamic Changes Of Jujube Tree's Fine Root Morphology In Northern Shaanxi

We used Jinzao,Goutouzao and Qiyuexian Chinese jujube trees to study the varying fine root morphology(diameter,root tissue density,specific root length,specific surface area)of fine roots from different phenological periods(germination stage,leaf extension early stage,leaf extension middle stage,whole leaf stage,fruit maturation stage,defoliation stage).we explored the seasonal dynamic changes of jujube trees' fine root morphology and the correlations between fine root morphology and weather.It can provide the basis for underground further researching and precise fertilization managemnets.We find that:1.As root order is increased,diameter and root tissue density increases,meanwile,specific root length and specific surface area decreases.2.The diameter of jinzao remains stable during the growing season.Root tissue density of fine roots(level 1-3)changed as a “M” curve.The trend of specific surface and specific root length is similar,like a “W”.The peaks of specific root length are germination stage,,whole leaf stage and defoliation stage.Valleys are leaf extension early stage,fruit maturation stage3.The 1st order fine root changes like “V”,the 2nd order fine root increases slowly,There is a slow decline from fruit maturation stage to defoliation stage,the 3rd order of fine root changes as a “M” curved.Specific root length and specific surface area of diiferent fine root order changes differently.Specific surface area of the 1st order fine root changes like“collapse V”,specific root length of the 1st order fine root changes like “inclined Z”.Specific root length and specific surface area of the 2nd order fine root declines gradually,which rises slightly from fruit maturation stage to defoliation stage.The 3rd order is relative stable.4.The diamaters and root tissue density of Qiyuexian rise steadily?Specific root length and specific surface area covers like a "W",three peaks are germination stage,whole leaf stage and defoliation stage.Two minimum values are leaf extension early stage and fruitmaturation stage.5.Siol temperature and the root conformation not relevant,There is reverse correlation between the siol humidity and the fine root diameters.Specific root length and specific surface area was positively associated with soil moisture.The relationship decreased with root order.