An In Vitro–Ex Vitro Micropropagation System for Hemp

Hyperhydricity of shoots initiated in vitro, poor shoot extension, inability cultures to maintain good growth over an extended time, and unsuccessful ex vitro rooting have limited the development a commercial scale micropropagation system for hemp ( Cannabis sativa ). We present culture initiation method that prevents hyperhydricity using vented-lid vessels with 0.2-µm pores medium containing agar at 1% (w/v). To optimize multiplication control (medium A) four treatment media B, C, D, E), varying inorganic nutrients vitamins were tested. Control A consisted 1× Murashige Skoog (MS) plus 3% (w/v) sucrose, 0.5 mg·L ?1 metatopolin, 0.1 gibberellic acid, 0.8% pH 5.7. The differed from as follows: 2.5× MS vitamins; added mesos [calcium chloride (anhydrous), magnesium sulfate potassium phosphate (monobasic) nutrients]; E, vitamins. Medium C E produced more microcuttings than 6 weeks after initial subculture all other treatments 9 12 weeks. Shoots grown on these two displayed optimal extension leaf lamina development; however, they exhibited slight chlorosis by media. In separate experiment, was supplemented ammonium nitrate 0, 500, 1000, or 1500 , 500 most best combination development. provide prerooting microshoots has resulted 75% 100% rockwool. Using 10 recently micropropagated plants, ?300 retip cuttings (cuttings taken new plants) harvested average weekly 90%. Retipping can produce nine-times many plants similar amount floor space stem derived traditional stock mother plants. micropropagation/retipping proposed be efficient way generate clonal liner commercial-scale production.