use Data::Dumper;
my %all_entry;
while (<DATA>) {
    chomp;
    next unless (/^>/);

    my ($line) = />.*\{((?:GI=\d+,\w+,\d+\-\d+;?)+)\}/;

    push @{ $all_entry{$1}{$2} }, $3
        while $line =~ /GI=(\d+),(\w+),(\d+\-\d+)/g;
}

print Dumper \%all_entry;
__DATA__
>r7.1 |SOURCES={GI=162960844,bw,0-4;GI=162960844,bw,9025576-9025608}|
>r6.1 |SOURCES={GI=152989753,bw,0-30;GI=152989753,bw,1877925-1877931}|