辣椒根系分泌物对辣椒种子萌发和幼苗生长的影响

Effects of Root Exudates on Seed Germination and Seedling Growth of Pepper

张掖市辣椒连作障碍逐年加重,根系分泌物自毒作用是引起辣椒连作障碍的一个重要因素。为克服辣椒连作障碍,以陇椒2号为试材,研究了辣椒根系分泌物对其种子萌发和幼苗生长的影响。结果表明,不同浓度的辣椒根系分泌物浸提液对辣椒种子萌发和幼苗生长均有一定的抑制作用,根系分泌物浸提液浓度为100 g/kg时对辣椒的生长抑制作用较弱,使辣椒种子的发芽率降低25.66个百分点,使辣椒幼苗的光合速率、蒸腾速率分别下降了0.97、0.25μmol/(m·s);根系分泌物浸提液浓度为300 g/kg时对辣椒生长的抑制作用最强,使辣椒种子发芽率降低53.33个百分点,使辣椒幼苗的光合速率、蒸腾速率分别降低了3.19、1.35μmol/(m·s)。可见,根系分泌物对辣椒的抑制作用与其浓度成正比关系。

The monocropping cropping obstacle of pepper in Zhangye has been increasing recently,and the self toxicity of root exudates is an important factor causing the monocropping cropping obstacle of pepper.Effects of root exudates on seed germination and seedling growth of pepper were studied in this experiment by using the Longjiao 2 as the test material,in order to provide references for the overcoming of the monocropping obstacle in pepper.The results showed that different concentrations of pepper root exudates could all inhibit pepper seed germination and seedling growth,whereas 100 g/kg of pepper root exudates showed weak inhibition effect which reduced the germination rate of the seeds,photosynthetic rate,and transpiration rate of the seedlings by 25.66 percent,0.97μmol(/m·s),and 0.25μmol(/m·s),respectively.300 g/kg of pepper root exudates showed the strongest inhibition effect against the growth of pepper,which reduced the germination rate of the seeds,photosynthetic rate,and transpiration rate of the seedlings by 53.33 percent,3.19、1.35μmol(/m·s),respectively.In conclusion,the allelopathic effect of root exudates on pepper growth is directly proportional to their concentration.