基于人为控水和自然水分胁迫下的甘蔗茎节生长变化OA北大核心CSTPCD

In order to understand the effect of water stress on the internode length of sugarcane,8 sugarcane varieties developed home and abroad with different drought tolerance were planted in barrels and in fields.Under the conditions of artificial water stress and natural rain-fed condition in fields,the plant height,stalk diameter and internode length of sugarcane were investigated during the harvest period.The results showed that,under the conditions of artificial water stress,drought caused 88%of sugarcane varieties to grow shorter,and the stem diameter of sugarcane decreased first and then increased(stem diameter of+13～+6 node)due to the artificial water stress and rehydration,and the internode length became significantly shorter and then increased.Under natural rain-fed condition infields,the plant heights of 8 sugarcane varieties in 2 test bases were 2.7～3.4 m in 2 years.Influenced by drought climate and other conditions,the relatively ideal sugarcane varieties judged by plant height were'ROC1''ROC22''GT21'and'CP80-1827'.Compared with artifical water stress,natural drought led to the reduction of sugarcane stem diameter with the most details in+7 leaf stems,the internode length becomed shorter and the shortest internode appeared in+8 and+9 leaf stems.Under the conditions of artificial water stress,the varieties with strong drought tolerance showed the high internode water stress index(IWSI)and internode water stress recovery index(IWSRI).While the varieties with strong drought tolerance showed the high IWSI and low IWSRI under natural rain-fed conditions in fields.In terms of recovery index,the normal internode length after drought rewatering was longer than that before drought,which showed that the moderate drought stimulated the growth of sugarcane.In general,water stress leaded to shorter plant height,smaller stem diameter and shorter internode length of sugarcane.The IWSI and IWSRI could be used to understand the growth difference of different sugarcane varieties stem nodes in response to water stress,and they could be as indexes to evaluate the drought tolerance of sugarcane varieties under drought conditions.The research on sugarcane drought tolerance could not completely rely on artificial water control to simulate drought,and the breakthrough research on sugarcane drought tolerance should focus on natural drought in field.