Biochar Enhances Rice Root Membrane Potential And Increases Nitrogen Uptake By Rice

Biochar is a black solid material obtained by calcination of plant stems such as straw,which contains a trace amount of nutrients for plant growth and development.In recent years,more and more researchers have studied the effects of biochar.Most studies have shown that addition biochar has a positive effect on soil,which can improve soil physical and chemical properties and promote plant growth and development.In this thesis,biochar was used as research object,and rice was used as research carrier.Experiments were carried out to compare the changes of soil and the growth of rice through the application of biochar,in order to clarify that biochar promotes rice growth and improves soil physical and chemical properties and provides a theoretical basis for the wide application of biochar.The following research results were obtained:1.In situ measurement of rice membrane cell potential,soil potential and soil pH by electrophysiological techniques,we found that after applying biochar,the cell membrane potential of rice roots increased by about 65 mV,the soil potential increased by about 85 mV,and the soil pH increased by about 0.5.The size of the root cell membrane potential is smaller as the distance from the root tip is shorter,and the soil potential is larger as the distance from the root tip is longer.The change soil pH is consistent with the soil potential.2.Different rice materials responded differently to the same biochar.When experimenting with Wuyunjing No.7,Nipponbare and 9311,it was found that the content of 15N absorbed in the same time was compared and it was found that after the application of biochar,Wuyunjing No.7 significantly increased the absorption of 15N,while 9311 showed no significant difference.At the same time,the expression of genes related to nitrogen uptake and transport after application of biochar was detected,and it was found that in rice leaves,The expression of nitrogen uptake and transport genes was significantly up-regulated in Wuyunjing No.7 and Nipponbare rice materials.The expression of OsNRT2.1 was significantly down-regulated in 9311 and the others were up-regulated.3.After the application of biochar,the total nitrogen and total phosphorus content of the soil did not change,and the total magnesium,total calcium,total sodium and total potassium content increased significantly.And the changes of soil microbes are more complicated.We examined the changes in the relative abundance of fungi and bacteria after adding biochar.The results showed that the effect of biochar had the effect of promoting or inhibiting the soil microbial vigor.After entering the soil,rice can absorb more nutrients,such as nitrogen,phosphorus,potassium,iron and other elements,and increase the growth significantly.We also found that after the application of biochar,the elements distribution of roots of rice is different.The root surface adsorbs more elements.In summary,after the application of biochar to the soil,the soil potential and the membrane potential of the roots both increased,which make the roots of rice more viable,and promote the roots to absorb more nutrients from the soil to satisfy its growth and development.