Screening and application of semi-solid gel formula for root growth observation
[Objective]Plant roots are important functional organs for plants to absorb soil moisture and nutrients.Studying plant roots helps to understand the interaction between plant roots and shoots and the response mechanism of plants to environmental changes.In this study,the stability and plant growth safety of single and compound of polymer absorbent resin(SAP)and carbomer U20(U20)were analyzed,and a semi-solid gel open culture method for plant root growth observation was established.[Method]Alocasia longiloba and Schefflera actinopylla were used as experimental plants,and a root box experiment was conducted with nutrient solution and SAP and U20 compound semi-gel formula.The 1/4 Hoagland′s nutrient solution was used as the control(CK).The stability of 1/4 Hoagland's nutrient solution(CK),0.3%SAP gel nutrient solution(T1),0.5%U2O gel nutrient solution(T2),0.4%U2O + 0.3%SAP gel nutrient solution(T3)and 0.5%U2O + 0.2%SAP gel nutrient solution(T4)were analyzed.The changes of root morphology,leaf chlorophyll,and nutrient uptake in these solutions were also explored.[Result]No obvious microbial contamination was observed in the solution of each treatment,flocculation and stratification occurred in T1,T2,and T3 during 5 weeks.The solution of T4 was as stable and clear as that of CK.Results of dynamic observation in leaves chlorophyll changes showed that there were no significant differences in SPAD value and total chlorophyll content between each treatment and CK at the same time in Schefflera actinopylla,and there was no significant difference in SPAD value between each treatment and CK in Alocasia longiloba(P>0.05).Compared with CK,T1 and T2 inhibited the root growth of Alocasia longiloba and Schefflera actinopylla.For Schefflera actinopylla,T1 and T2 significantly decreased the total root length by 51.59%and 47.48%and root surface area by 30.59%and 32.27%(P<0.05).Compared with CK,T1 and T2 significantly decreased the total root length of Alocasia longiloba by 44.72%and 45.86%,and the root surface area of Alocasia longiloba by 29.23%and 27.75%(P<0.05).Also,T1 and T2 showed significantly lower biomass and the contents of nitrogen,phosphorus,and potassium in shoots and roots than those of CK(P<0.05).There were no significant differences in total root length,root surface area,the contents of nitrogen,phosphorus,and potassium,and the biomass of shoots and roots in Alocasia longiloba or Schefflera actinopylla among T3,T4,and CK.Different from CK in which roots showed drooping growth,T4 provided a better condition to spread the roots of Alocasia longiloba or Schefflera actinopylla.The growth state of roots in soil medium was well simulated in T4 in which the lateral roots and fine roots were spread at a certain angle.[Conclusion]The nutrient solution with 0.5%U20 + 0.2%SAP can form a stable semi-solid gel for a long time.This semi-solid gel can better meet the requirements of simulated plant root growth in soil than others.Moreover,the growth of Alocasia longiloba or Schefflera actinopylla in this semi-solid gel showed no significant differences in plant biomass,leaf chlorophyll,root morphological changes,and nutrient absorption compared with those in the pure nutrient solution in a short time.The nutrient solution with 0.5%U20 + 0.2%SAP can be used to establish an open culture method with semi-solid gel for plant root growth observation.
万方数据
维普
