Preventing chimerism in potato (Solanum tuberosum L.)

Abstract

A fast neutron irradiation experiment using two different dose rates has been performed on the potato variety Desiree in order to obtain chimera-free mutants. Both tubers and tuber parts (cross sections) were de-eyed at different moments before and after irradiation. Adventitious sprouts successively developing on the callus in the holes of excised eyes were separated from the treated tubers and planted individually. So called 'grouped' sprouts were separated. Results indicated that (practically) chimerafree mutants can be obtained by de-eying tuber parts shortly before irradiation, by applying relatively high dose-rates and by taking adventitious sprouts which develop not earlier than three months after irradiation.Separation of the grouped sprouts demonstrated that each part originated from a single original cell.

Dihaploid potatoes in mutation breeding: Some preliminary results

“…Table 1 further reveals that within the 50 rad/min object there is a steady increase in overall mutation frequency and also in uniform mutants. Also the increase in overall mutation frequency in the 50 rad/ min object is in agreement with the results of NAVAR and DAYAL (1970) and VAN HARTEN et al (1972). The increase in uniform mutants was explained elsewhere ( VAN HARTEN et al, 1972) by assuming that the number of initial cells from which the successive sprouts (either axillary or adventitious) develop, decreases in later stages.…”

“…by NAYAR and DAYAL (1970) and by VAN HARTEN et al (1972). Studying 6 plants per clone, in 54 clones treated with 2 kR, only 3 clearly aberrant types (5.5 ~) were obtained, whereas 78 clones treated with 3 kR produced 11 (14 ~) clear mutants.…”

In vitro adventitious bud techniques for vegetative propagation and mutation breeding of potato (Solanum tuberosum L.). II. Significance for mutation breeding

“…These figures are about the same as the best results from potato mutation experiments in which in vivo adventitious sprouts were used (VAN HARTEN et al ., 1972 ;VAN HARTEN & BOUTER, 1973) . It further appears that when adequate facilities for in vitro work are available, the amount of work involved does not surpass that for in vivo production of adventitious sprouts .…”

“…when inducing adventitious sprouts on eye-excised tuber parts, the mutation frequencies obtained with the in vitro methods described are very high . The average mutation frequency for the irradiated explants of the present experiment was 74 .3 % (Table 1) whereas in previous experiments with the same cultivar and identical methods of scoring mutants for material from in vivo origin, the yield was 24-38 % ( VAN HARTEN et al ., 1972 ;VAN HARTEN & BOUTER, 1973) .…”

“…Tetraploid and dihaploid clones of this cultivar were also used before in a number of in vivo mutation experiments . This cultivar has the advantage that a rather high number of characteristics can easily be mutated and observed (VAN HARTEN et al ., 1972 ; VAN HARTEN & BoUTER, 1973) . In those in vivo experiments 24-38 % of (visible) mutations were obtained, using adventitious sprouts which grew from callus in the holes of excised tuber eyes or arose after removing at regular intervals all sprouts that had developed on normal tubers .…”