谷子萌芽期抗旱性初步研究

Preliminary investigation in the drought resistance of foxtail millet during germinating stages

为了探讨谷子萌芽期抗旱性相关指标,筛选抗旱谷子品种,采用高渗透性能的PEG-6000作为水分胁迫剂,研究不同PEG浓度对谷子萌发的影响,结果表明:在20%PEG胁迫下降低了种子的发芽率,其中赤谷6号、赤谷8号、大白毛、赤谷16、安革5号降幅较大,分别为44,37,29,28,27个百分点。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,其中相对发芽率、相对发芽势、相对胚根长与萌发抗旱指数呈极显著正相关,相关系数分别为0.859**、0.744**、0.725**,可以作为谷子萌芽期抗旱性鉴定的指标。相对胚芽鞘长度与萌发抗旱指数呈显著正相关,相关系数为0.529*。相对胚芽长、相对侧根数与抗旱指数相关性不显著。抗旱性评价结果表明:15份谷子品种中,晋谷54、长农36、黄粘谷(00009380)、A2-2053、黄粘谷(00009838)、小乌谷的萌发抗旱指数分别为0.89、0.89、0.79、0.57、0.56、0.52,抗旱性较好。

In order to explore the index of drought resistance and screen drought tolerance millet cultivars, high permeability of PEG- 6000 as the agent of water stress was used to research the effect on germination of 15 millet cultivars under different concentrations of PEG. The results showed that the millet germination rate diversely decreased under the 20% PEG stress.Cultivars Chigu 6, Chigu 8, Dabaimao, Chigu 16 and Ange 5 demonstrated the most reduction by 44%,37%,29%,28% and 27%, respectively. 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 germination percentage, germinating energy and roots length(r=0.859**; r=0.744**; r=0.725**), which could be used for the indicator of millet germination stage. Coleoptile length also had a positive correlation with GDRI to a certain extent(r=0.529*). Bud length and lateral root number did not correlate significantly with germination drought resistance index. Drought resistance evaluation results showed that among 15 copies of foxtail millet varieties, Jingu 54, Changnong 36, Huangniangu(00009380), A2-2053, Huangniangu(00009838) and Xiaowugu had better drought resistance than the others, their germination drought resistance index were 0.89, 0.89, 0.79, 0.57, 0.56 and 0.52, respectively.