| The technique of low energy N+ ion beam implanting developed recent decade years, catched wide attention for its advantage over the conventional radiation breeding practice. Though this technique has made evident achievements in breeding program, the mechanism is unclear. The glutenin and gliadin are important elements which affect the qulity of wheat. However, the sparsity of high qulity subunit and its combination of glutenin inhibited the improvement of wheat quality seriously in China. The present study was to investigate the effects on the meiosis of wheat pollen mother cells (PMCs), the variances of glutenin and gliadin and agronomic characterizations by varying dosage implantation of N+ ion beam (E=20 KeV, D=3.6-10.8 1016N+/cm2). Moreover, it expects to put this new technique into theoretical study and wheat breeding program. The results as follows:1. The analysis of PMCs by low energy N+ ion beam implantated, revealed that a lot of chromosome aberrances occurred, such as chromosme bridge, chromosome fragment, univalent, polyvalent and microkernel, and it exhibited dosage effect.2. In this study, A-PAGE and SDS-PAGE had been firstly applied in analyzing the influence of band types of glutenin and gliadin induced by a series of dosage of low energy ion beam implantation. The results showed that the aberrance of glutenin and gliadin were induced effectly using low energy N+ ion beam implantation. The extent of the aberrance was Glu-Dl (high dosage5.2% and low dosage2.8%) >Glu-Bl (high dosage4.27%andl. Iowdosage4%) >Glu-Al (high dosage4.2% and low dosage 0%) in turn and exhibit dosage offect. A plenty of new subunits different from its parents were found, such as 1 subunit(account of 0.9%) and 2*(account of 3.3%) coded in loci Glu-Al; 13+16 subunit (account of 1.4%); 13+19 subunit (account of 0.47%); 7 subunit (account of 2.4%) coded in Glu-Bl; 2+10 subunit (account of 1.9%) and 5+10 subunit (account of 3.3%) coded in Glu-Dl. The 7 new combination induced by low energy N+ ion beam implantation are 1, 7+8, 5 + 10 (0.47%); 2*, 7+8, 2+12 (0.94%); 2*, 7, 2 + 10 (0.94%); null, 7+8, 5 + 10 (1.4%); 2* , 13 + 16, 5 + 10 (0.47%); null,13 + 19, 2+12(0.47%); null, 7, 2+10(0.9%). Besides this, the low energy N+ion beam implantation had been induced a lot of aberrance in zone and y zone of gliadin, the variance ratio was 5.6%. However, there weren't aberrance found in a and P zone.3. The result of the present study showed that low energy N+ ion beam implanting could affect the germination rate and germination vigor indoor and the growing of seedlings in fields. When the implantation dosage increased, the germination rate and germination vigor declined. The germination rate and germination vigor at 10 1016 N+/cm2 were 59.03% and 43.05% respectively compare with the checking lines and the difference was significant (PO.01). With the increasing of implantation, the survival ratio of seedlings in fields declined gently unlike that of the germination vigor indoor. The growing of seedlings was bated in high dosage, While, the middle dosage implantation facilitate to the growing and survival of seedlings.4. N+ ion beam implanting restrained obviously the growth of the seedlings and the first leaf stage. Moreover, it could affect the growth of the root. 30keV, 4xlOI6N+/cm2 was the least dosage. The low dosage (30KeV 2xl016 N+/cm2) could facilitate the growth of roots, however, higher dosage exhibited retarding. Furthermore, N+ ion beam implanting could also result in albinism seedlings, stripe leaves and abnormal seedlings etc.5. The results of investigation to the MI lines revealed that N+ ion beam implantating obviously affected the agronomic characterizations, such as development phase, strain shape, plant height, tasseling stage, and yield. The commercial characters of the seeds, such as size, color and rigidity etc., changed as well.6. In the lines of Mi-M3, a serial of varieties with high qulity subunits and agronomic aberrances were selected, which would be useful in wheat breeding program and quali...
|
PDF Full Text Request