Mw. Farnham, GENETIC-VARIATION AMONG AND WITHIN UNITED-STATES COLLARD CULTIVARS AND LANDRACES AS DETERMINED BY RANDOMLY AMPLIFIED POLYMORPHIC DNA MARKERS, Journal of the American Society for Horticultural Science, 121(3), 1996, pp. 374-379
A collection of collard (Brassica oleracea L,, Acephala group) germpla
sm, including 13 cultivars or breeding lines and 5 landraces, was eval
uated using randomly amplified polymorphic DNA (RAPD) markers and comp
ared to representatives of kale (Acephala group), cabbage (Capitata gr
oup), broccoli (Italica group), Brussels sprouts (Gemmifera group), an
d cauliflower (Botrytis group), Objectives were to assess genetic vari
ation and relationships among collard and other crop entries, evaluate
intrapopulation variation of open-pollinated (OF) collard lines, and
determine the potential of collard landraces to provide new B, olerace
a genes, Two hundred nine RAPD bands were scored from 18 oligonucleoti
de decamer primers when collard and other B. oleracea entries were com
pared, Of these, 147 (70%) were polymorphic and 29 were specific to co
llard, Similarity indices between collard entries were computed from R
APD data and these ranged from 0.75 to 0.99 with an average of 0.83, C
ollard entries were most closely related to cabbage (similarity index
= 0.83) and Brussels sprouts entries (index = 0.80), Analysis of indiv
iduals of an OP cultivar and landrace indicated that intrapopulation g
enetic variance accounts for as much variation as that observed betwee
n populations, RAPD analysis identified collard landraces as unique ge
notypes and showed them to be sources of unique DNA markers, The syste
matic collection of collard landraces should enhance diversity of the
B, oleracea germplasm pool and provide genes for future crop improveme
nt.