Allelopathic effects of decomposed liquids derived from Chenopodium ambrosioides L.litters and the response mechanism of root border cells in crops
To explore the allelopathic mechanism of the invasive plant Chenopodium ambrosioides L.,maize(Zea mays L.),soybean[Glycine max(L.)Merr.],and tartary buckwheat[Fagopyrum tataricum(L.)Gaertn.],which are commonly cultivated and susceptible to C.ambrosioides invasion,were selected as receptor plants.The investigation was conducted using the pure agar suspended air culture method and a Root Border Cells(RBCs)removal test.The study examined the effects of decomposed liquids from C.ambrosioides litters on the RBCs located in the root tip of the recipient crop.Additionally,it investigated the influence on the length of young roots and the activity of Pectin Methyl Esterase(PME)in the root cap,both in the presence and absence of RBCs in the root crown.The allelopathy Synthesis Effect(SE)index was employed to assess the impacts.Findings revealed that decomposed stems and leaves exhibited allelopathic effects on the three recipient plants,with SE index values ranking as follows:tartary buckwheat(0.295),soybean(0.239),and maize(0.163).Moreover,the allelopathic influence on indigenous species(tartary buckwheat and soybean)surpassed that on exotic species(maize).The allelopathic effects of leaf decomposers were generally stronger than those of stems.Additionally,it was observed that the allelopathic effect intensified with shorter decomposition times.The number of RBCs and PME activity in the three crops exhibited a highly positive correlation.With prolonged treatment times or reduced decay periods,PME activity decreased,the number of RBCs decreased,the mortality rate of RBCs increased,and root elongation was reduced in higher concentration treatment groups.After the removal of RBCs,the degree of root growth inhibition mostly increased.The PME activity of maize and tartary buckwheat increased after RBCs removal and 12-hour treatment,and the number of RBCs was positively correlated with the change in root length.The findings suggest that plants boost PME synthesis and release more RBCs to safeguard the growth of young roots during the early stages of allelopathic stress.When stress surpasses a certain threshold,PME synthesis declines,leading to a reduction in RBC numbers and an increase in mortality,ultimately inhibiting root growth.However,soybean exhibits distinct response mechanisms.
basic disciplines of environmental science and technologyChenopodium ambrosioides L.litter decompositionallelopathyroot border cellsresponses
NETL
NSTL
万方数据
