Preliminary Studies On In Vitro Culture And Genetic Transformation In Agrostis Stolonifera And Zoysia Matrella

Agrostis stolonifera (creeping bentgrass) is one of the perennial stolon herbs. It can form a lawn which is elaborate, homogeneous and dense like a green blanket, and is the first choice in the golf course green. Zoysia matrella (manilagrass), namely manilagrass, is one of the mainly cultivated turfgrass species in the south of China. It is a very significant task to screen and nurture excellent turfgrass varieties. In this paper, the study was divided into the following three parts. In the first part, taken L-93 seeds of creeping bentgrass as explants, compared the effects of different concentrations of sucrose, different combinations and concentrations of growth regulators, dark treatments, and different additives on callus induction. In the second part, taken the stolons of fine-leaf mutant of L-93 as explants, compared the effects of different combinations and concentrations of growth regulators, different concentrations of sucrose, different gelling agents, and different nodal explants on callus induction. In the third part, taken the callus of creeping bentgrass and manilagrass, stolons of fine-leaf mutant of L-93 and manilagrass as explants, established an Agrobacterium-madiated transformation system preliminary. The primary results were summarized as follows:1. In experiment 1, the rate of callus induction was increased in the first and then lowed down, with the increase of sucrose concentrations. Callus induction was the highest when the concentration of sucrose was 40g/L. In the 9 combinations of plant growth regulators, 2 mg/L 2,4-D and 0.1 mg/L 6-BA was optimal owning highest frequency of callus induction. And the callus wass made obvious proliferation in dark treatment and additionof coconut milk or proline.2. In experiment 2, in combinations of plant growth regulators, 2 mg/L 2,4-D and 0.1 mg/L 6-BA was optimal owning highest frequency of callus induction. And when 2,4-D concentration fixed 2 mg/L and 6-BA concentration fixed 0.1 mg/L, the frequency of callus induction was highest. Among the 6 concentrations of sucrose treatments, callus induction was the highest when the concentration of sucrose was 40g/L. In the comparison of 4 gelling agents, Phytagel was the best one to induce callus. In the different nodal explants, the node nearest the shoot tip was the most efficient for callus induction.3. In experiment 3, the effects of glyphosate at different concentrations on the callus growth and regeneration of creeping bentgrass and manilagrass were screened. when glyphosate concentration was at 1.0 mM, the regeneration rates of creeping bentgrass and manilagrass were 15.5% and 4.5% respectively. When glyphosate concentration was at 2.0 mM, the regeneration rates were 8.75% and 1.78% respectively . Also, the effects of glyphosate at different concentrations on shoot formation from the stolon nodal explants of creeping bentgrass and manilagrass were screened. When glyphosate concentration was at 1.0 mM, one shoot was regenerated from the stolons of the fine-leaf mutant of creeping bentgrass, and the regeneration rates was 1.2%.