Study On Stress Of Exogenous Cinnamic Acid On Cucumber And Regulation Measures In Greenhouse

Phenolic acids is one of the most important elements caused by the cucumber continuous cropping of autotrophic effects.Cinnamic acid is the main phenolic substance which has been proved to cause the cucumber continuous cropping.It leads to the serious accumulation of cinnamic acid due to perennial continuous cropping,while current control measures are inefficient and difficult to make the facilities cucumber autotoxicity due to phenolic acid easeing,and has difficulty to achieve the purpose of improving quality and efficiency.In this test,we studied the toxicity and stress mechanism of cinnamic acid on the facilities cucumber combined culturing test in the sand and field experiment.We have studied the effects of traditional amount of bio-organic fertilizer,microbial agent,bio-carbon(carbonized corn cob)and attapulgite organic fertilizer,and have provided the basis on regulation control of its toxic effects in greenhouse.The results showed:1.Under the condition of sand culture,the low concentration of cinnamic acid promoted the chlorophyll content of cucumber seedlings significantly,which was beneficial to the accumulation of root morphology and accumulation of aboveground biomass.The activity of SOD was significantly increased when the concentration of phenylacrylic acid situate on 30-100 mg kg-1.When the concentration of cinnamic acid was 30-100 mg kg-1,SOD,POD and CAT was higher than that of 100 mg kg-1,the plasma membrane permeability and plant MDA content were significantly increased.2.In the greenhouse field experiment,the bio-organic fertilizer combined with microbial agents and carbonized corn cob was beneficial to improve the nutritional situation under 100 mg kg-1 cinnamic acid stress,plant height and stem diameter of cucumber plants.The activities of SOD,POD and CAT were significantly increased,and content of MDA was reduced.The bio-organic fertilizer on the activities of SOD and POD was better.3.Under the situation of 100 mg kg-1 cinnamic acid stress,bio-organic fertilizers combined with microbial agents and carbonized corn kernels promoted the growth of shoots and roots in plants,and the growth of shoots was stronger than that of roots,and the root-to-shoot ratio was significantly lower.This treatments were most favorable enhance the accumulation of N,P and K in the roots and stems of the late foliage.Bio-organic fertilizer combined with microbial agents and the single-applied attapulgite organic fertilizer were beneficial to the accumulation of P and K in the leaves most significantly.4.Under the situation of 100 mg kg-1 cinnamic acid stress,bio-organic fertilizer combined with microbial agents and carbonized corn cob were beneficial to improve soil structure and soil aeration performance,to increase the nutrient contents such as available P,available N and total N and total P increased by 68.26%?95.95%?28.57%and 10.81%,to enhance the activity of urease,catalase and sucrase,and to optimize the soil microbial flora and increase the total amount of microorganisms.The available Fe and Zn were increased,the amount of available Fe and available Zn were increased by 34.94%and 44.87%than CK1 in 20-40 cm layer soil,respectively.The contents of available K,available N and organic matter and total N were increased.The effect of organic manure combined with microbial agents on the content of available P,total N and total P in this area was significant,and the activity of alkaline phosphatase was significant.5.Under the situation of 100 mg kg-1 cinnamic acid stress,combination with bio-organic fertilizer,microbial agent and carbonized corn kernel was more obvious to improve the quality of continuous cropping cucumber.This treatment was the most beneficial to increase the content of cucumber titratable acid,soluble protein,soluble solids and Vc,and reduced the accumulation of NO3--N in cucumber,and to enhance tne content ratio of sugar and sugar,the yield increased by 43.46%compared with continuous cropping soil.In summary,combination of bio-organic fertilizer,microbial agents and carbonized corn is the most conducive to control on cucumber continuous autotoxicity in greenhouse,to improve soil micro-ecological most significantly.Plowing soils deeply soil before the next planted,combinated 4.2 t hm-2of carbonized corn kernels with 16.5 t hm"2 biological organic fertilizer,and application of 67.5 L hm-2 was beneficial to alleviate the stress effect of 100 mg kg-1 cinnamic acid on the facilities cucumber and to improve the quality and economic benefit of the facilities.