Three rice landraces that have been continuously cultivated in Yuanyang County for hundreds
of years by the local Hani people and three modern varieties cultivated in this area for 3-5 years were
comparative tested on seven major agronomic characteristics at six different altitudes in the Yuanyang
paddy field. The results indicated that agronomic characteristics of the landrace varieties, such as plant
height, panicle length and number of effective panicles of landraces had no significant difference at
different altitudes, whereas, those agronomic traits fluctuated in the modern varieties. In the Yuanyang
terrace area, the Yuanyang landraces showed greater diversity in phenotype and better adaptation
compared to the modern varieties