Use of growth inhibitor chlormequat chloride in potato culture in vitro

The publication presents data on the use of growth inhibitor chlormequat chloride in in vitro potato culture on varieties of different maturity groups: Meteor (early), Zekura (mid-early), and Northern Lights (mid-season). Five dosages of the investigational product were studied, ranging from 0.1125 to 1.8 g/l. It was found that in maximum doses of the product there was a strong inhibition of all growth processes in all varieties. The research results showed that the most optimal concentration of chlormequat chloride is 0.225 g per 1 liter of Murashige and Skoog medium. At this dose, on 30th day of cultivation, there was a decrease in the height of microplants from the control by 63.2-85.1%, in the root length - up to 15.0% and their number - up to 22.8% and an increase in the number of internodes by 6.5-22,0 % depending on the variety. The investigational product had an effect on formation of microtubers; in the Meteor variety, their largest number was 89.5% in the nutrient medium with a dose of 1.8 g/l, in the Zekura variety - 93.0% in the nutrient medium with a dose of 0.9 g/l. The new technique makes it possible to lengthen the periods between cuttings of test-tube plants by 2.3 times. This, in turn, reduces the cost of maintaining the in vitro collection material of potatoes in the summer-autumn period, and improves its quality, since each additional cutting cycle affects a more rapid degeneration of the variety. Also, microplants grown with growth inhibitor during subsequent relocation to a standard Murashige and Skoog medium did not show an aftereffect