谷子萌芽期抗旱性鉴定研究

为了探索谷子种子萌发期相关抗旱性形态和生理生化指标，从而为谷子品种的早期抗旱性鉴定提供更多理论依据。通过PEG渗透胁迫人工模拟干旱条件，对20个谷子品种进行了萌芽期抗旱性研究。以种子的萌发抗旱指数为依据进行谷子萌芽期抗旱性筛选，将20个谷子品种分为五类。研究结果表明：在渗透胁迫条件下，谷子的发芽率、发芽势降低，幼根和幼芽的生长受到不同程度的抑制。其中发芽势、发芽率和幼芽长度与萌发抗旱指数呈极显著正相关(r=0.90**；r=0.73**；r=0.63**)，根长和侧根数与萌发抗旱指数呈正相关(r=0.48*；r=0.51*)，胚芽鞘长度与萌发抗旱指数相关性不显著。分析表明，发芽势可作为萌芽期抗旱性鉴定的一级指标；发芽率和幼芽长度可作为抗旱性鉴定的二级指标；根长和侧根数可作为萌芽期抗旱性鉴定的三级指标。鉴定谷子萌芽期抗旱性，可以以抗旱指数为主，结合其他5项指标进行综合评价。

Study on Drought Resistance of Millet in Seeding Emergence Stage

The study aims to explore the drought resistance index and physiological and biochemical indexes at millet seed germination, which provide more theory basis for early appraisal of drought resistance. The study on drought resistance of twenty maize varieties at germination stage was conducted through adopting PEG solution simulated soil drought treatment. Using GDRI as basis to screen millet with drought resistance at germination period, twenty maize varieties were classified into five categories. Results showed that: germinating energy and germination percentage were decreased, the growth of young roots and buds were depressed at various levels under osmotic stress. There were positive correlations between GDRI and germinating energy, germination percentage and bud length (r=0.90**; r=0.73**; r=0.63**), roots length and lateral root number also had a positive correlation with GDRI to a certain extent (r=0.48*; r=0.51*). While coleoptile length did not correlate significantly with germination drought resistance index. Analysis showed that, germinating energy could be used for the first indicator of millet germination stage; germination percentage and bud length can be used for the second indicator; roots length and lateral root number could be used for the third indicator. When evaluating the GDRI of millet and other five indicators, drought resistance index can be used as a main marker and the other five indexes as supplements.