薏苡种质资源萌发期抗旱性鉴定及抗旱指标筛选

干旱是影响薏苡生产的主要因素之一,鉴定薏苡种质资源的抗旱性,筛选抗旱指标,培育抗旱品种,对薏苡产业的发展具有重要意义。本研究首先以抗旱性不同的6份薏苡种质为材料,通过调查5个不同浓度的PEG-6000水溶液模拟干旱胁迫下的发芽率,确定了薏苡萌发期模拟干旱胁迫的最适PEG-6000水溶液渗透势为-0.1 MPa。然后以-0.1 MPa的PEG-6000水溶液模拟干旱胁迫,探讨50份薏苡种质发芽势、发芽率、萌发指数、芽长、芽粗、芽鲜重、芽干重、根长、根粗、根鲜重和根干重的变化,利用综合评价法对50份薏苡种质进行萌发期抗旱性鉴定及抗旱指标筛选。结果表明,干旱胁迫对薏苡萌发期各指标均有极显著影响。筛选出萌发期抗旱性强的薏苡种质分别为yy18-1、yy14-3和yy13-1,可为薏苡抗旱育种、抗旱机理及干旱调控缓解机制的研究提供基础材料。芽长、芽干重、根长、根鲜重和根干重可作为薏苡种质资源萌发期简单、直观的抗旱性评价指标。

Identification and Indices Screening of Drought Resistance in Job's Tears Germplasm Resources at Germination Stage

Drought is one of the important problems for Job's tears production.Identification,indices screening,and cultivar breeding of drought resistance in Job's tears germplasm resources are important for Job's tears industrial development.The germination rates of 6 Job's tears germplasms with different drought resistance were tested under 5 different concentrations of PEG-6000 water solution to determine the optimal osmotic potential of PEG-6000 water solution simulated drought stress at germination stage.The results showed that-0.1 MPa was the optimum osmotic potential of PEG-6000 water solution simulated drought stress at germination stage for Job's tears germplasm resources.The changes of germination energy,germination rate,germination index,bud length,bud diameter,bud fresh weight,bud dry weight,root length,root diameter,root fresh weight,and root dry weight of 50 Job's tears germplasms were investigated under-0.1 MPa PEG-6000 water solution simulated drought stress to identify the drought resistance and screen the drought resistance indices of Job's tears germplasm resources by comprehensive evaluation method at germination stage.The results showed that drought stress had significant effects on all indices of Job's tears at germination stage.yy18-1,yy14-3 and yy13-1 were identified as drought resistance Job's tears germplasms at germination stage,which could be provide basis materials for the researches on cultivar breeding,mechanism,and regulation and alleviation mechanism of drought resistance in Job's tears.The bud length,bud dry weight,root length,root fresh weight,and root dry weight could be used as the simple and intuitive identification indices of drought resistance in Job's tears germplasm resources at germination stage.