Evaluation of Cold Tolerance in Wild Sugarcane Germplasm Resources under Field Conditions

摘要

In January 2016,Kunming underwent 52 hours of rain and snow weather below 0℃.In order to identify the cold tolerance of different wild sugarcane germplasm resources in low temperature and snow disasters,cold injuries of 38 shares of wild sugarcane germplasm resources,which were collected during2012-2013 and preserved in the germplasm resource nursery of Sugarcane Research Institute,Yunnan Agricultural University,were surveyed to evaluate the cold tolerance based on sugarcane cold tolerance index(CTI)=0.5×shoot tip growing point injury index+0.3×node injury index+0.2×internode injury index.The results showed that cold tolerance indexes of four wild sugarcane varieties demonstrated a descending order of Erianthus arundinaceum Retz.(0.7),Erianthus rockii Keng(0.5),Saccharums pontaneum L.(0.3),Erianthusf ulvus Nees.(0).Greater cold tolerance indexes indicate poorer cold tolerance.Thus,Erianthusarundinaceumhad the poorest cold tolerance,while Erianthus fulvus exhibited the strongest cold tolerance.In addition,there were significant differences in cold tolerance among different Saccharum spontaneumclones.The 23 Saccharum spontaneumclones could be divided into four grades,including 1clone with the poorest cold tolerance that accounted for 4.3%,5clones with poor cold tolerance that accounted for 21.7%,14 clones with strong cold tolerance that accounted for 60.9%,and 3clones with the strongest cold tolerance that accounted for 13.0%(2012-23,2012-32,2012-37).Especially,2012-23 exhibited extremely strong cold tolerance.This study provided the scientific basis for screening of cold-tolerant wild sugarcane germplasm resources and selection of cold-tolerant parents.