Roles of plant growth substance in callus induction of Achyranthes bidentata

<p> <strong>In this research, callus from leaves, petioles and stems of <em>Achyranthes bidentata</em> was evidently initiated by plant growth substance, in which 2,4-dichlorophenoxyacetic acid (2,4-D) was very important to callus induction, but effects of other plant growth substances were various, and the optimum combination of plant growth substances for callus induction from leaves, petioles and stems was respectively obtained. Compared with callus induction from leaves and petioles, callus induction from stems was easier, and the higher induction rate and bigger mass of callus from stems were obtained. This study showed that the dedifferentiation capacity</strong><strong> of various explants from </strong><strong><em>Achyranthes bidentata</em></strong><strong> was obviously different, and effects of plant growth substance on callus induction from various explants of <em>Achyranthes bidentata</em> were significantly diverse.</strong><strong></strong></p>

Growth Rate Model and Temperature-Changing Fermentation Process of Pseudomonas Syringae Pv. Mori M4-13

Pseudomonas syringaepv. mori M4-13 is a new coronatine-production strain isolated from mulberry trees. As a high efficient plant growth substance, coronatine is difficult to obtain from the traditional bacteria under the high temperature. The fermentation temperature cannot be greater than 301K. However, the coronatine production is strictly growth associated. Therefore, biomass growth and accumulation of coronatine should be studied coordinately. In this paper, the growth rate of the strain was studied by the square root model, and the temperature-changing fermentation pattern of coronatine was optimized. In the fitting function of , the value of b was 0.03276, c was 0.1759, R2= 0.99. Based on the results, the optimal growth temperature of Pseudomonas syringae pv.moriM4-13 is 305K. The accumulation of coronatine reaches the peak, when the strain was incubated at the 305K for 3 days, following with the fermentation at 291K for another 3days. This fermentation pattern lay a solid foundation for the large-scale applications in the industrial production.