珠芽 is read as しゅが (shuga) and means bulbil.
しゅが
shuga
しゅざん
calculation on an abacus
たま
ball (i.e. a testicle)
しゅぎょく
jewel
しゅしん
nucellus
ずず
rosary
きのめ
bud of Japanese pepper tree (Xanthoxylum piperitum)
め
germinal disk (in an egg)
はつが
germination
ほうが
early sign
しんめ
sprout
ばくが
malt
むせいが
gemma