Intercropping of crops that can secrete bacteriostatic active substances can not only inhibit the occurrence of disease but also have an important effect on plant growth.However,the effects of dandelion intercropping ...Intercropping of crops that can secrete bacteriostatic active substances can not only inhibit the occurrence of disease but also have an important effect on plant growth.However,the effects of dandelion intercropping on pepper blight control and pepper growth remain unclear.In this study,the control effect of dandelion on pepper blight was studied by inoculating the pepper leaves with Phytophthora infestans,and it also discusses the correlation of the occurrence of pepper epidemic disease with the pepper canopy environment,soil environment,pepper photo-synthesis,and yield index.The results showed that best plant distance for dandelion intercropping was 20 cm(P20),and the control effect reached 43.31%.As compared to the CK,SOD enzyme,POD enzyme,and PAL enzyme were significantly up-regulated during the growth of pepper;chlorophyll content in pepper leaves was significantly increased;photosynthetic characteristics were significantly increased;stem diameter and yield of crop pepper were effectively improved;and the quality of the pepper product was better,but intercropping dandelion resulted in a significant decrease of nutrients in the soil environment of pepper,so a reasonable intercropping distance was needed.The correlation analysis shows that the incidence of pepper blight(A)was significantly positively correlated with soil temperature(Q),intercellular carbon dioxide(L),and canopy air temperature(O).The incidence of capsicum blight(A)was significantly negatively correlated with chlorophyll content(F),net photo-synthetic rate(K),stomatal conductance(M),ww rate(N),soil sucrase activity(W),vitamin C(AB),and leaf PAL enzyme(J).Finally,it was deduced that intercropping dandelion could effectively control the occurrence of pepper blight while also demonstrating a complex interaction with the pepper growing environment.展开更多
A mixture of six Georgia isolates of Phytophthora capsici (Leon.), the causal agent of phytophthora blight, were used for greenhouse mass screening of over 700 accessions of Capsicum annuum for both stem blight and fo...A mixture of six Georgia isolates of Phytophthora capsici (Leon.), the causal agent of phytophthora blight, were used for greenhouse mass screening of over 700 accessions of Capsicum annuum for both stem blight and foliar blight. From this screening, it was determined that resistance to both forms of the disease were relatively common in the germplasm, but resistance to one form of the disease was not strongly correlated to resistance to the other form. Ten accessions previously shown to possess root rot resistance were tested for resistance to stem rot and leaf blight, and were found to also be highly resistant to these forms of the disease. It appears that single accessions have resistance to foliar, stem and root rot caused by P. capsici, which may simplify breeding for resistance to all three forms of the disease.展开更多
Greenhouse studies were performed to determine the reactions of 10 “California Wonder” (Capsicum annuum) accessions to the three forms of Phytophthora blight (root rot, stem blight and foliar blight) caused by Phyto...Greenhouse studies were performed to determine the reactions of 10 “California Wonder” (Capsicum annuum) accessions to the three forms of Phytophthora blight (root rot, stem blight and foliar blight) caused by Phytophthora capsici. Differences in root rot, stem blight and foliar blight severities among accessions were significant. The accessions consistently differentiated into two groups across the three disease syndromes. Simple sequence repeat (SSR) markers showed variability both within and between accessions of California Wonder. The variability in the responses to the three forms of Phytophthora blight does not warrant its usefulness as a standard susceptible control in studies involving the Capsicum-P. capsici patho-system.展开更多
[ Objective ] The paper was to explore the combined application technique of organic fertilizer and two biocontrol agents against pepper blight in green- house hot pepper in Qinghai Province. [Method] By L4 （23）orth...[ Objective ] The paper was to explore the combined application technique of organic fertilizer and two biocontrol agents against pepper blight in green- house hot pepper in Qinghai Province. [Method] By L4 （23）orthogonal design, the effects of combined application of two biocontrol agents against pepper blight and organic fertilizer on control effects against pepper blight and the yield of hot pepper were studied in greenhouse hot pepper base in Ledu County of Qinghai Province. [ Result] The effects of various factors affecting the relative control effect against pepper blight in sequence were biecontrol agent A5 〉 biecontrol agent B2 〉 organic fertilizer, and the optimal combination was organic fertilizer 1 800 kg/hm^2, agent B2 30 kg/hm^2 and agent A5 45 kg/hm^2. The effects on hot pepper yield in sequence were organic fertilizer 〉 biocontrol agent B2 〉 biocontrol agent AS, and the optimal combination was organic fertilizer 900 kg/hm^2 , agent 132 15 kg/hm^2, agent A5 22.5 kg/hm2. [ Conclusion] Combined with control effect of pepper blight and yield benefit, the application technique of biocontrol agents pro- moted in local hot pepper production could be confirmed as follows ： agent A5 45 kg/hm^2, agent B2 15 kg/hm^2, organic fertilizer 900 kg/hm^2 ; the field control effect at this moment could reach 76.31%, the yield could reach 35 573 kg/hm^2 , and the newly increased output value could be 13 029 yuan/hm^2 with input and output ratio of 1： 7.9.展开更多
[ Objectlve] The paper was to explore the antibacterial activity of S. fiavescens extracts against pepper blight. [ Methods] Growth rate method and sus- pend-drop method were used to measure the inhibition effect of d...[ Objectlve] The paper was to explore the antibacterial activity of S. fiavescens extracts against pepper blight. [ Methods] Growth rate method and sus- pend-drop method were used to measure the inhibition effect of different solvents and concentrations of S. fiavescens extracts on F. oxysporum. [Result] The inhibi- tion rate of etude extracts of S. flavescens extracted by ethyl acetate and acetone was significantly higher than that of ethanol. With the increasing concentration of ethyl acetate crude extracts of S. flavescens, its inhibition effect against myeelial growth and spore germination of F. oxysporum signitieantly increased. When the mass concentration was 40 g/L, its inhibition rates against myeelial growth and spore germination of F. oxysporum were 94.48% and 89.01%, respectively. [ Con- clusion] The active substance contained in S. flavescens roots had strong inhibition activity against pepper blight, which had the potential value for further research and development.展开更多
基金supported by the Young Talent Project of Northeast Agricultural University(20QC03)Disciplinary Team Project of Northeast Agricultural University.
文摘Intercropping of crops that can secrete bacteriostatic active substances can not only inhibit the occurrence of disease but also have an important effect on plant growth.However,the effects of dandelion intercropping on pepper blight control and pepper growth remain unclear.In this study,the control effect of dandelion on pepper blight was studied by inoculating the pepper leaves with Phytophthora infestans,and it also discusses the correlation of the occurrence of pepper epidemic disease with the pepper canopy environment,soil environment,pepper photo-synthesis,and yield index.The results showed that best plant distance for dandelion intercropping was 20 cm(P20),and the control effect reached 43.31%.As compared to the CK,SOD enzyme,POD enzyme,and PAL enzyme were significantly up-regulated during the growth of pepper;chlorophyll content in pepper leaves was significantly increased;photosynthetic characteristics were significantly increased;stem diameter and yield of crop pepper were effectively improved;and the quality of the pepper product was better,but intercropping dandelion resulted in a significant decrease of nutrients in the soil environment of pepper,so a reasonable intercropping distance was needed.The correlation analysis shows that the incidence of pepper blight(A)was significantly positively correlated with soil temperature(Q),intercellular carbon dioxide(L),and canopy air temperature(O).The incidence of capsicum blight(A)was significantly negatively correlated with chlorophyll content(F),net photo-synthetic rate(K),stomatal conductance(M),ww rate(N),soil sucrase activity(W),vitamin C(AB),and leaf PAL enzyme(J).Finally,it was deduced that intercropping dandelion could effectively control the occurrence of pepper blight while also demonstrating a complex interaction with the pepper growing environment.
文摘A mixture of six Georgia isolates of Phytophthora capsici (Leon.), the causal agent of phytophthora blight, were used for greenhouse mass screening of over 700 accessions of Capsicum annuum for both stem blight and foliar blight. From this screening, it was determined that resistance to both forms of the disease were relatively common in the germplasm, but resistance to one form of the disease was not strongly correlated to resistance to the other form. Ten accessions previously shown to possess root rot resistance were tested for resistance to stem rot and leaf blight, and were found to also be highly resistant to these forms of the disease. It appears that single accessions have resistance to foliar, stem and root rot caused by P. capsici, which may simplify breeding for resistance to all three forms of the disease.
文摘Greenhouse studies were performed to determine the reactions of 10 “California Wonder” (Capsicum annuum) accessions to the three forms of Phytophthora blight (root rot, stem blight and foliar blight) caused by Phytophthora capsici. Differences in root rot, stem blight and foliar blight severities among accessions were significant. The accessions consistently differentiated into two groups across the three disease syndromes. Simple sequence repeat (SSR) markers showed variability both within and between accessions of California Wonder. The variability in the responses to the three forms of Phytophthora blight does not warrant its usefulness as a standard susceptible control in studies involving the Capsicum-P. capsici patho-system.
文摘[ Objective ] The paper was to explore the combined application technique of organic fertilizer and two biocontrol agents against pepper blight in green- house hot pepper in Qinghai Province. [Method] By L4 （23）orthogonal design, the effects of combined application of two biocontrol agents against pepper blight and organic fertilizer on control effects against pepper blight and the yield of hot pepper were studied in greenhouse hot pepper base in Ledu County of Qinghai Province. [ Result] The effects of various factors affecting the relative control effect against pepper blight in sequence were biecontrol agent A5 〉 biecontrol agent B2 〉 organic fertilizer, and the optimal combination was organic fertilizer 1 800 kg/hm^2, agent B2 30 kg/hm^2 and agent A5 45 kg/hm^2. The effects on hot pepper yield in sequence were organic fertilizer 〉 biocontrol agent B2 〉 biocontrol agent AS, and the optimal combination was organic fertilizer 900 kg/hm^2 , agent 132 15 kg/hm^2, agent A5 22.5 kg/hm2. [ Conclusion] Combined with control effect of pepper blight and yield benefit, the application technique of biocontrol agents pro- moted in local hot pepper production could be confirmed as follows ： agent A5 45 kg/hm^2, agent B2 15 kg/hm^2, organic fertilizer 900 kg/hm^2 ; the field control effect at this moment could reach 76.31%, the yield could reach 35 573 kg/hm^2 , and the newly increased output value could be 13 029 yuan/hm^2 with input and output ratio of 1： 7.9.
基金Supported by National"863"Project(2004AA247010)~~
文摘[ Objectlve] The paper was to explore the antibacterial activity of S. fiavescens extracts against pepper blight. [ Methods] Growth rate method and sus- pend-drop method were used to measure the inhibition effect of different solvents and concentrations of S. fiavescens extracts on F. oxysporum. [Result] The inhibi- tion rate of etude extracts of S. flavescens extracted by ethyl acetate and acetone was significantly higher than that of ethanol. With the increasing concentration of ethyl acetate crude extracts of S. flavescens, its inhibition effect against myeelial growth and spore germination of F. oxysporum signitieantly increased. When the mass concentration was 40 g/L, its inhibition rates against myeelial growth and spore germination of F. oxysporum were 94.48% and 89.01%, respectively. [ Con- clusion] The active substance contained in S. flavescens roots had strong inhibition activity against pepper blight, which had the potential value for further research and development.
