Institute of Genetics

Effect of low positive temperature on callusogenesis and somatic embryogenesis of maize

--Climenco (Kravchenko), OA, Jacota, AG

The purpose of this study was to determine sensitivity of maize to cold during callus and somatic embryo formation. Fourteen inbred lines (MK01, W47, Rf7, XL12, 092, A239, P101, Co125, MK159, MK390, 459, F2, Mo17, B73) were used as experimental material. Tissue cultures were initiated from 12-day-old embryos (total number = 1951). Immature embryos and callus cultures were treated by low positive temperature (+10 °C+12 °C) for 24, 48 and 72 hours. The data were processed by two-factor analysis of variance.

The results indicate that genotype, temperature and genotype × temperature interaction effects are highly (P<0.001) significant for callusogenesis and somatic embryogenesis. It was found that in most of the cases, exposure to low temperature results in a decrease in frequency of callus and somatic embryo formation, with the exception of 459, A239 and XL12 inbred lines which had higher values of these characters in comparison with the control variants. It should be noted that somatic embryogenesis frequency of the inbreds 459, MK159, 092, P101, MK01, F2, Rf7, MK390 proved to be less than 20%. The data also indicate that the other inbreds (Co125, A239, XL12, W47, Mo17, B73) were more resistant to low positive temperature (the frequency of somatic embryogenesis was higher than 30%). The other result was that for each of the 14 inbreds the best combinations of factors studied were also determined.