Mutation breeding for yield andPhytophthora infestans (Mont.) de Bary foliar resistance in potato (Solanum tuberosum L. cv. Golden Wonder) using computerized image analysis in selection

Abstract

SummaryUsing visual selection for off-types and image analysis to select against maturation mutants, a line combining improved late blight resistance and yield was isolated in an in vitro mutagenesis programme from a population of 2101 putative mutants. The adventitious regener.ants from mutagenesis treatment, including spontaneous mutants (somaclonal variants), were subjected to serial subculture of the apical bud in vitro and two cycles of apical cuttings in vivo to breakdown chimeras. The selected line was stable in trials over five years; others were unstable or failed to combine improvement in late blight resistance with high yield. Leaf and tuber image analysis was used to characterize selected lines. Lines that differed most from cv. Golden Wonder in yield and late blight resistance were more easily distinguished from the control by image analysis. The role of image analysis in negative selection and in determination of the relatedness of mutants to the control is discussed.

Biotechnology approaches to overcome biotic and abiotic stress constraints in legumes

“…These methods induce point mutations, deletions, or insertions, respectively and have been useful in breeding for biotic (Bhagwat & Duncan, 1998;Kowalski & Cassells, 1999) and abiotic (Fuller & Eed, 2003;Khan et al, 2001) stress in non-legume crops. In legumes most effort has occurred with nitrogen fixation (Sagan et al, 1994), and mutants with resistance or tolerance to stresses have not been described.…”

The use of image analysis to study developmental variation in micropropagated potato (Solanum tuberosum L.) plants

“…may contribute to producing an addedvalue micropropagation product. Here and previously (Cassells & Sen, 1995;Fitzgerald, 1996;Kowalski & Cassells, 1999), it has been shown that ontogenetic (developmental) variation within the potato plant and between or within populations can be detected by differences in leaf parameter means, or by the presence of statistical outliers in the population. Here, leaf parameters have been shown to be related with crop maturation and can be used to compare the relative maturity of different populations.…”

“…Epigenetic or non-heritable variation may also be associated with pleiotropic changes in disease susceptibility (Cassells et al, 1993;Cassells & Sen, 1996). Differences in developmental maturity (ontogenetic differences) between individuals within and between potato populations, can be detected by quantifying changes in leaf morphology using computerised image analysis (Cassells et al, 1991;Cassells & Sen, 1996;Cassells et al, 1997;Kowalski & Cassells, 1999). Here, the application of computerised image analysis to potato microplants is investigated with reference to the characterisation of ontogenetic or developmental variation.…”

Breeding For Ornamentals: Classical and Molecular Approaches

“…It is assumed in the latter cases that retention of the characteristics of the parent genotype is required, that is, that the mutants be near-isogenic with the parent, as in a flower color series. polyploids and gross aneuploids using flow cytometry, and morphological aberrants using image analysis, and (v) select for near-isogenicity using computerized image analysis (Kowalski and Cassells, 1999). use of bud irradiation (Sonnino et al, 1986); (ii) facilitate chimeral breakdown, e.g.…”

“…use of bud irradiation (Sonnino et al, 1986); (ii) facilitate chimeral breakdown, e.g. 4; Kowalski and Cassells, 1999). select for resistance to fungal toxins; (iv) select against gross aberrants, e.g.…”