沼液浸种对水稻种子萌发及幼苗生长的影响

Effects of Soaking of Seeds With Biogas Slurry on Germination and Seedling Growth of Rice

为探讨沼液对水稻早期萌发和幼苗生长的影响,以不同浓度沼液对日本晴水稻(Oryza sativa)种子浸种24 h后催芽,分析其种子萌发及幼苗生长情况。结果表明,2%沼液浸种可增加水稻幼苗根数和芽生物量,但降低了幼苗根生物量,该浓度沼液浸种对种子萌发率、萌发速率、幼苗芽长、茎粗及总根长没有显著影响(P>0.05)。更高浓度的沼液浸种对水稻种子萌发和幼苗生长均产生抑制作用。沼液浸种对根生物量的影响大于芽生物量,从而导致各浓度沼液处理组芽/根生物量比值均大于对照。对呼吸速率的分析结果进一步佐证了沼液处理对萌发后期水稻种子具有不利影响。建议水稻早期生产中慎用沼液。

With the development of biogas projects,a massive amount of fermentation residues has been produced in the rural areas of China. Hence how to recycle those residues and what their potential values are have attracted great interests from both scientists and engineers. Biogas slurry is supposed to be applied as fertilizer in rice cultivation. To explore effects of soaking rice seeds with biogas slurry on seed germination and growth of rice seedlings,rice seeds（ Oryza sativa）were soaked separately in biogas slurries different in concentration for 24 h before the seeds were sown into seed beds for germination,and germination rates and seedling growth was monitored for comparison between treatments different in concentration of biogas slurry used in soaking. Results show that in the treatment using 2% of biogas slurry,the seedlings increased their root number and shoot biomass,but decreased their root biomass. However,this treatment did not have much effect on seed germination rate and speed,shoot length,shoot diameter and root length of the seedlings. Treatments higher in biogas slurry concentration inhibited both seed germination and seedling growth. As the effect of biogas slurry on root was higher than on shoot,the seedlings in all the treatments had higher shoot / root biomass ratios than CK. Analysis of respiration rate of rice seedlings reveals that treatment of rice seeds with biogas slurry may have some negative impacts on germination of seeds at the late stage. So mechanism of biogas slurry affecting seed germination and seedling growth could be complicated. As a conclusion,it is recommended that cautions be taken in using biogas slurry to treat seeds in the early stage of rice cultivation.