| Development of adventitious root is an important research topic for the micropropagation. The rhizogenesis includes the cell dedifferentiation and rediffrentiation, which is regulated by genes of organogenesis. The functional proteins play an important role in this process. The hormones and polyamines are closely related to the selective expression of genes, so they affect on the adventitious root organogenesis. In this paper, the effects of exogenous hormones and polyamines on the protein and the dynamic changes of endogenous hormones and polyamines were studied with the M26 in vitro during the adventitious root organogenesis. The results were summarized as follows:1. Lateral root primordium was not found in the stem segment of M26 in vitro. The induced root primordium originated from the division and differentiation of vascular cambium cell developed into the adventitious roots. The anatomical observation showed that the formation of adventitious roots included three stages: (1) cell dedifferentiation, (2) root primordium formatting, (3) adventitious roots differentiating.2. The treatment of exogenous polyamines at 103-10-5mol·L-1 enhanced the occurrence of adventitious root primordiums of M26 in vitro. The treatment of Spd 1014 mol-L-1 had the best effect on average root number and rooting rate. Put treatment had more lateral roots than Spd and Spm did, and the optimum treatment was concentration of 10-5 mol ? L-1.3. The results of marinating with IB A indicatedthat marinatingin the solution of 100mg·L-1 IB A for 24 hours before transferred to the shoot rooting medium increased the rooting index obviously.4. The changes of protein patterns were detected by SDS-PAGE. The results indicated that both quantity and quality of protein differed in the stages of development of the adventitious root formation. After transferred to the shoots rooting medium, five protein bands(26.8kDa, 37kDa, 40.3kDa, 43kDa and 66kDa)decreased or disappeared and four protein bands(38.5kDa, 42kDa, 53.2 kDa and 55.5kDa) was increased. Meanwhile, four new protein bands(26 kDa, 27.7 kDa, 32.5 kDaand 45kDa) began to express. Three protein bands expressed efficiently during the entire stage of rooting, and their contents accumulated gradually.The32.5kDa and 55kDa protein bands included the rooting related specific proteins.5. Two new protein bands with 66kDa and 43kDa in the stem segments were induced since that were marinated in the lOOmgl/'lBA solution for 12 hours before transfered to the rooting medium. The similar results were observed when the period of marination was extended to 16 and 20 hours. Another small proteins with 28.5 kDa and 27 kDa were detected when treated for 16 and 20 hours .When the period of marination was extended to 24 hours, 42kDa proteins down-expressed and 27kDa proteins up-express, meanwhile, two specific protein bands with 40.3kDa and 36kDa began to present.Effects of Spd on proteins in stem segment differed from stages after treatment. IBA treatment inhibited the expression of 42.9 kDa specific proteins that were induced by Spd, but Spd treatment can not inhibited 36.3kDa specific proteins that were induced by IBA.6. Marinating in the lOOmgl/'lBA solution or 10"3molL"' Spd solution for 12 hours then transferred to the 1/2MS + l.Omg-L"1 IAA medium for 5 days shown obvious deffernces in protein expression.After IBA treatment, two protein bands presented and two protein bands expressed highly, but Spd did not.7. The difference of protein bands were in the range of pH 6.9 to 7.6 based on the testing by IEF-PAGE. The results indicated that the pi of the total proteins ranged from pH 6.9 to pH7.6.8. The treatments of IBA or Spd increased the peak contents of IAA significantly. Spd treatment made the peak of IAA content appear one day earlier than that of IBA treatment and the control. Two peaks of endogenous ABA were tested for Spd treatment. The Spd treatment enhanced the content of endogenous ABA, but IBA decreased. The treatments with IBA or Spd significantly deseased the content of endogenous ZR and GA3, as compared with control.9. The treatments of IBA or Spd decreased endogenous Spm content totally, Spd treatment increased endogenous Spd content in higher efficiency than IBA treatment. The content endogenous Put increased initially then decreased. The tendency of endogenous polyamines was of increase fluctuatingly and slowly. PAs contents of two treatments reached at the peaks when the root primordiums were formatting. After treating for 7 days, the content of PAs with Spd treatment was in the highst level, and IBA treatment was higher compared to the control. The content of PAs was accelerated during the root primordium and reached at the peak through adventitious root differentiating stage.
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