PEG模拟干旱对向日葵杂交种苗期生物量和根系形态的影响

Effect of PEG Simulated Drought on Biomass and Root Morphology of Sunflower Hybrids at Seedling Stage

以油葵杂交种F51、F60和食葵杂交种辽嗑杂2号为试验材料,采用营养液水培方式,以不同浓度的PEG6000模拟干旱胁迫,研究不同干旱胁迫程度对向日葵苗期生物量、根冠比和根系形态的影响。研究结果表明:PEG模拟干旱胁迫使向日葵杂交种幼苗不断失水,出现萎蔫现象,使其生物量的积累受到抑制。随着PEG浓度的增加,胁迫时间的持续,生物量受抑制程度加强,向日葵幼苗的根冠比呈增加趋势,其原因可能是由于地上部生物量积累受干旱胁迫抑制程度大于根部的缘故。低浓度的PEG模拟干旱胁迫可以促进向日葵杂交种幼苗根系的伸长生长,但随着PEG浓度的增加根系的总根长同样会受到抑制,并且不同向日葵杂交种苗期根系形态,对不同程度干旱胁迫的响应不同。

The effects of different concentrations of PEG 6000 on the biomass, root to shoot ratio and root morphology of sunflower seedling stage were studied by using the nutrient solution hydroponics as test material for the oil sunflower hybrid F51, F60 and confectionary sunflower hybrid Liaokeza 2. The results showed that PEG simulated drought stress resulted in continuous water loss and wilting of sunflower hybrid seedlings, which inhibited the biomass accumulation. With the increase of PEG concentration, the duration of stress and the degree of biomass inhibition were enhanced. The root to shoot ratio of sunflower seedlings showed an increasing trend compared with CK. The reason may be that the shoot dry weight accumulation was more inhibited by drought stress than the root. Low-concentration PEG simulated drought stress can promote the elongation and growth of the seedling roots of sunflower hybrids, but the total root length of the seedling is also inhibited with the increase of PEG concentration. Moreover, root morphology of different sunflower hybrids at seedling stage has different responses to different degrees of drought stress.