Fallopia japonica

The Fallopia japonica var compacta examined were either male-sterile or female-sterile. The introduction of new species was limited to the genetic base of the fertile hybrid progeny. Some hybrids were sterile, while some had low fertility (e.g. the hybrid between Polygonum cuspidatum, also known as Fallopia japonica and Polygonum sachalinense, also known as Fallopia sachalinensis yields a hexaploid). 

Centaurea nigra Scleranthus annuus Polygonum aviculare Fallopia japonica... 

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