Study On Cryopreservation Of Turf And Pasture Germplasm

In this paper the filtration of cryopreservation reagent combination of perennial ryegrass calli was studied. It also studied effects of length of cryopreservation time,lawn and herbage seeds moisture content and thaw temperature on cryopreservation and change of seeds hereditary characters before and after cryopreservation. Specific result is as follows:1 After cryopreservation reagent combination of perennial ryegrass calli was filtered by orthogonal experiment,the results showed that the best cryopreservation reagent was aqueous solution containing 5%DMSO,15%PEG,30%glycerin,15%sucrose. Calli survival rate could reach estimatedly 95.2% of that before cryopreservation.2 Cryopreservation of perennial ryegrass(Lolium perenne L.) and sainfoin(Onobrychis viciaefoli L.) seeds was studied in this paper by measuring and analyzing the relationship of seed germination rates, germination index, electroconductibility, dehydrogenase activity, the MDA content and soluble sugar to make sure the effects of length of cryopreservation time and seeds moisture content. The results showed that perennial ryegrass and sainfoin seeds of natural moisture content could be cryopreserved in LN2. Difference of cryopreservation time on seeds was not significant; There was no distinct difference of Perennial ryegrass before and after cryopreservation, and adaptive changes happened to sainfoin seeds after cryopreservation compared to that before cryopreservation; Seed moisture content was not critical factor determining cryopreservation effects, and appropriate range of moisture content for perennial ryegrass and sainfoin seeds cryopreservation was 9.2%~11.8% and 5.6%~9.0% respectively.3 The paper studied the effects of thaw temperature 0℃,25℃,37℃,50℃on seeds of perennial ryegrass(Lolium perenne L.),tall fescue(Festuca arundinacea L.),white clover(Trifolium repens L.),sainfoin(Onobrychis viciaefoli L.) and alfalfa(Medicago sativa L.). The result showed that there were not distict influence for sainfoin,white clover and tall fescue. The statement of each index's change considered synthetically, better temperature for alfalfa and perennial ryegrass was 37℃a nd 37-50℃respectively.4 Through analysis on catalase isoenzymes chart mensuration of seeds of perennial ryegrass, tall fescue, white clover, sainfoin and alfalfa, the paper studied the effect of cryopreservation on seeds heredity property. The result showed that there was no difference in catalase isoenzymes chart for perennial ryegrass and tall fescue seeds before and after cryopreservation and cryopreservation might make no difference on their heredity property. By using equal ways in mensurating catalase isoenzymes chart just as the former two kinds of seeds, catalase isoenzymes chart of white clover,sainfoin and alfalfa seeds did not exist both before and after cryopreservation and particular cause was not clear yet.