11个紫薇品种花粉活力及柱头可授性日变化规律

Diurnal Variation of Pollen Viability and Stigma Receptivity of 11 Lagerstroemia indica Varieties

为准确掌握紫薇杂交授粉最佳时间,提高杂交成功率,以花粉活力测定方法筛选为基础,对11个紫薇品种花粉活力日变化规律进行了探讨,并用联苯胺-过氧化氢法对柱头可授性日变化规律进行了研究。结果表明,液体离体培养法最适合紫薇花粉活力测定,培养基为蔗糖200 g/L+硼酸150 mg/L+氯化钙10 mg/L+PEG-4000 15 g/L。在自然开花当天8:00~16:00,11个品种花粉活力基本呈现先增后减的趋势,9:00~13:00花粉量较大,花粉活力较高,基本保持在70%以上,其他时间花粉活力相对较低,14:00以后花粉量明显变少,16:00以后大部分品种花粉丧失活力。在自然开花当天8:00~16:00,11个品种柱头可授性基本呈现出先增强后减弱的规律,在11:00~12:00,柱头可授性最强,其他时间柱头可授性相对较弱。由此得出,用这11个品种进行杂交育种时,理论上9:00~13:00适合进行花粉的采集,11:00~12:00适合进行杂交授粉,育种工作中可结合其他影响因素,根据不同品种花粉和柱头可授性的具体情况进行适当调整。

In order to accurately grasp the best time of cross pollination of Lagerstroemia indica and improve the success rate of cross pollination, the diurnal variation of pollen vigor of 11 Lagerstroemia indica varieties was studied based on the screening of pollen vigor determination methods, meanwhile the diurnal variation law of stigma acceptability was studied by benzidine hydrogen peroxide method. The results showed that the liquid in vitro culture method was the most suitable for the determination of crape myrtle pollen vitality. The culture medium was sucrose 200 g/L+boric acid 150 mg/L+calcium chloride 10 mg/L+PEG-4000 15 g/L. From 8:00 to 16:00 on the day of natural flowering, the pollen vitality of 11 varieties basically increased first and then decreased. From 9:00to 13:00, the pollen quantity was large and the pollen vitality was high, which was basically maintained at more than 70%. At other times, the pollen vitality was relatively low. The pollen quantity decreased significantly after14:00, and most varieties lost their pollen vitality after 16:00. From 8:00 to 16:00 on the day of natural flowering,the stigma acceptability of 11 varieties basically showed the law of strengthening first and then weakening. Between 11:00 and 12:00, the stigma acceptability was the strongest, and the stigma acceptability was relatively weak at other times. It can be concluded that when these 11 varieties are used for cross breeding, 9:00~13:00 is suitable for pollen collection and 11:00~12:00 is suitable for cross pollination. In the breeding work, other influencing factors can be combined to make appropriate adjustments according to the specific conditions of pollen and stigma acceptability of different varieties.