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Abstract The collected species including L. aurea、 L. radiata(2n
、3n)、L. chinensis、L. longituba、L. radiata var. pumila、L. sprengeri、L. al
biflora、L. incarnata and L. guangxiensis，the interspecific hybrid(L. aurea×
L. radiata) and its backcross progenys(L. aurea×F1 and L. radiata×F1) were u
sed for karyotypic analysis. The backcross progenys of L.×Aureadiata were als
o served as target to trace its gametic karyotype and to investigate the karyo
typic variation. Maximal number and frequency of nucleoli were examined among
Lycoris species .In this experiment is also intending to improve the technique
of C-banding method inorder to establish C-banding idiograms of L. aurea and
L. radiata.According M、T and A chromosomal types, the karyotype of Lycoris sp
ecies could be categorized into three groups.M-T group, the L. aurea represent
s as 2n=14=8M+6T,both L. chinensis and L. longituba 2n=16=6M+10T which can be
distinguished from the arm ratio of the longest telocentric centromere chromos
ome length/the t-shortest (Tl/Ts).In A groups, L. radiata and L. radiata var.
pumila 2n=22A, the former appear heteromorphic satellite chromosome(SAT)；but
the latter is homomorphic, However, L. sprengeri was one SAT.In M-T-A group ,
the L. albiflora、L. incarnata and L.×Aureadiata were respectively assessed a
s 2n=5M+1T+11A、4M+3T+22A and 4M+3T+11A。The L. incarnata 2n=29=4M+3T+22A=33 a
rms could as considered as triploid. In triploid groups, both L. radiata and L
. guangxiensis 3n=33A. Additionally, latter is characterized one small extra-c
hromosome.Some of the backcross progenys of L.×Aureadiata were assessed as 2n
=17=5M+3T+9A、15=7M+4T+4A、14=8M+6T and 22=22A。 Although, they are varied in
chromosome number and karyotype, but still corresponded to Lycoris rule with t
he same total 22 large arms. The gametic types contributed by the interspecifi
c hybrid could be traced as n=1M+9A(8A+1A')+1m、3M+1T+4A(3A+1A")、4M+3T and 11
A respectively. The nucleotype of functional gametes were still coincident wit
h 11 arms principles, but the changes in chromosomal rearrangement(A',A")and s
mall extra-chromosome(m) were also observed.L. longituba, L. incarnata, L. rad
iata(3n) and L. guangxiensis were examined to be maximal four nucleoli. L. rad
iata(2n), L. radiata var. pumila, L. sprengeri have two. Hybridy F1 and L. alb
iflora have three. In L. aurea×F1 backcross progeny(2n=17)it is evident that
the L. aurea parental chromosomes complement showing more than four secondary
construction(SC),interpreted that some SCs are not active for nucleolar format
ion. The best C-banding of pretreatment method Lycoris is modified as aceti
c acid(AC)、5％Ba(OH)2 at room temperature for 1 min 、20×SSC solution 12 mi
nutes at 60℃,then Giemsa staining and Ba(OH)2 treatment again for 7 min. or b
y modified ASG process and Ba(OH)2 at room temperature for 7 minutes. The
modified C-banding number in L. aurea and L. radiata were surveyed as be 102 a
nd 140 bands respectively. The four M type chromosomes of L. aurea could be di
scriminated by non banding regions. The third A chromosomes of L. radiata is c
haracterized with a large non banding pattern in the central regions. Addition
ally, the first and forth chromosomal pairs exhibited to be heteromorphic band
ing pattern or bimorphic C-banding pattern.72
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