The Study On Effects Of OsmiR156Overexpression On The Biological Characteristics Of Oryza Sativa L. At Thetillering Stage

Rice (Oryza saliva L.) biological characteristics such as tiller number plant type and so on have important effects on rice yield. OsmiR156plays a key role in the growth and development of rice. OsmiR156constitutive overexpression of Ubil and OsmiR156stem specific overexpression of D18p were got through T-DNA inserted into the plasmid pWM101that it was transformed into rice cultivar Nipponbare (WT). Random soil pot experiment of three materials and random soil pot experiment of three materials sprayed plant growth substances were designed. Through compare biological characteristics of transgenic rice materials D18p, Ubil and their parent WT at early tillering stage, middle tillering stage and late tillering stage, in order to provide reference basis for genetic improvement of yield traits in rice. The main results were as follows:1. Ubil showed plant bushy stunt, leaves in Ubil were narrower and shorter than those in WT, Ubil was little small branches. Spike length is about half of WT. The spike seeds of Ubil is empty flat. D18p plant type was similar with WT plant type, plant height of D18p was lower than that of WT, tiller number of D18p is slightly higher than that of WT, Spike type and spike length were no significant difference between D18p and WT.2. Leaf net photosynthetic rate and IAA oxidase activity of Ubil were the highest among three materials at the late tillering stage. Catalase and peroxidase activity of OsmiR156overexpression materials were higher than those in WT. Leaf auxin content and abscisic acid content in D18p or Ubil was higher than those in WT.3. The correlation between tiller number and leaf auxin content, tiller number and leaf IAA oxidase activity, they all showed a positive linear correlation in three materials of D18p, Ubil and WT.4. Plant growth substances spraying experiments show the following results:Ubil plant height is most sensitivity to GA3. The phytohormones content was significant difference between OsmiR156overexpression materials and WT after sprayed IAA and GA3. ZR and IAA content in OsmiR156overexpression materials were higher than those in WT, and GA1and ABA content were lower than WT.