Powdery mildew of cucumber(Cucumis sativus L.)is a destructive disease caused by Podosphaera xanthii(Castagne)U.Braun&Shishkoff.This study aimed to investigate the antifungal effect of extracts of Ulva lactuca,Spi...Powdery mildew of cucumber(Cucumis sativus L.)is a destructive disease caused by Podosphaera xanthii(Castagne)U.Braun&Shishkoff.This study aimed to investigate the antifungal effect of extracts of Ulva lactuca,Spirulina platensis,and Nostoc muscorum against P.xanthii and to improve the physiological and morphological traits of cucumber under commercial greenhouse conditions.The chemical composition of the individual extracts from U.lactuca,S.platensis,and N.muscorum was analyzed utilizing High-performance Liquid Chromatography(HPLC)and Gas Chromatography/Mass spectrometry(GC/MS).Cucumber plants were sprayed twice with 5%of the crude extracts of U.lactuca,S.platensis,and N.muscorum and their mixture(U.lactuca,S.platensis,and N.muscorum).The fungicide Topas 100 EC(Syngenta)was applied at the recommended dose(0.250 mL/L)only for comparison.The HPLC analysis indicated that the U.lactuca extract was the richest in phenolic compounds(605.84µg g^(−1)DW)compared to cyanobacterial extracts of S.platensis(214.77µg g^(−1)DW)and N.muscorum(462.97µg g^(−1)DW).The GC-MS spectrum analysis of methanolic extracts revealed 12 compounds in N.muscorum,11 compounds in S.platensis and 22 compounds in U.lactuca extract.In the 1st experiment,among treatments,the combined mixture(U.lactuca,S.platensis,and N.muscorum)and U.lactuca extract revealed the remarkable disease reduction attained 74.35%and 71.42%,respectively.However,the highest disease reduction was attributed to fungicide Topas 100 EC with value reached 85.28%.A similar pattern of results was also noted during the 2^(nd)experiment.In both experiments,the extract of S.platensis had the lowest effectiveness in lowering the DS and AUDPC of powdery mildew disease.The combined mixture and U.lactuca extract resulted in a substantial(p<0.05)increase in plant lengths,fresh and dry weights,leaves number,fruit number,and weight and yield/plant.Cucumber plants treated with either the extract of U.lactuca or the combined mixture exhibited the highest activity(0.084 and 0.088 U mL^(−1)min^(−1))for peroxidase and(1.64 and 1.62 U mL^(−1)min^(−1))for catalase,respectively,in the second experiment.The greatest increase in total phenolic content(7.97 mg g^(−1)FW)was noticed in plants following treatment with the combined mixture.The treatment with U.lactuca and S.platensis revealed a significant increase in carotenoids contents,reached up to 17.99 and 17.53 mg g^(−1)FW,respectively.We,therefore,support the need for considering sustainable management of powdery mildew of cucumber using the compounds derived from U.lactuca,S.platensis,and N.muscorum and to improve cucumber growth.展开更多
The burning of agricultural waste is a major cause of environmental pollution.In this study,we sought to prepare biochar from agricultural waste as a source material for the preparation of carbon nanoparticles(CNPs).S...The burning of agricultural waste is a major cause of environmental pollution.In this study,we sought to prepare biochar from agricultural waste as a source material for the preparation of carbon nanoparticles(CNPs).Surface morphology,hydrodynamic particle size,and purity and crystallinity of CNPs were extensively investigated using transmission electron microscopy(TEM),zeta sizing,and X-ray diffraction(XRD)spectroscopy,respectively.The CNPs were subsequently immersed in a solution of potassium nitrate(KNO_(3))to prepare a CNPs/NK nanocomposite(CNPs loaded with nitrogen(N)and potassium(K))as a nanocomposite fertilizer for common bean(Phaseolus vulgaris L.).The CNPs/NK nanocomposite was sprayed as a foliar fertilizer at 0,10,20,30,and 40 mg L^(-1)on common bean plants 25 d after sowing on a farm in Shebin El-Kom,El-Monifia,Egypt.The growth,yield,and quality of common bean were investigated during two successive growing seasons(2017 and 2018).The highest seed yields of 2.04 and 2.01 t ha^(-1)and the highest values of growth parameters including plant height of 61.5 and 59.2 cm,number of leaves per plant of 35 and 35,number of flowers per plant of 83.3 and 82.7,and plant fresh weight of 148.7 and 152.8 g plant^(-1)were obtained when using the CNPs/NK nanocomposite at a concentration of 20 mg L^(-1)during the 2017 and 2018 growing seasons,respectively.展开更多
Subsistence farming,a form of cultivation in which almost all crops or livestock are used to maintain farms and the farm family,leaving little,surplus for sale and trade.Pre-industrial farming peoples all over the cou...Subsistence farming,a form of cultivation in which almost all crops or livestock are used to maintain farms and the farm family,leaving little,surplus for sale and trade.Pre-industrial farming peoples all over the countries of the worldwide apply subsistence agriculture system and take advantage of the possibilities available to them from land and water resources in all locations of agriculture sites.The agricultural production has become more specialized and developed in the subsistence farming system,and farmers have produced abundant production from many horticulture crops that are traded among them and achieve their selfsufficiency from those crops.展开更多
Rhizoctonia solani Kühn and Sclerotium rolfsii Sacc.are the primary soil-borne plant diseases responsible for sig-nificant reductions in global crop yields.The primary goal of this study was to investigate the ant...Rhizoctonia solani Kühn and Sclerotium rolfsii Sacc.are the primary soil-borne plant diseases responsible for sig-nificant reductions in global crop yields.The primary goal of this study was to investigate the antifungal potentials of clove essential oil(CEO),nanoemulsion form(CEONE)and chitosan/nanoemulsion nanocomposite(CS/CEONE)against R.solani and S.rolfsii through in vitro and in vivo trials.Both CEONE and CS/CEONE were prepared and investigated for their physical chemical and morphological characterization.The poisoned medium method was utilized to evaluate the inhibitory effects of CEO,CEONE and CS/CEONE on the mycelial growth and enzymatic activity of R.solani and S.rolfsii.The changes of hyphae of R.solani and S.rolfsii in response to treating with CEONE and CS/CEONE were observed with scanning electron microscope(SEM).The results revealed that CEONE have larger size 86±3 nm and a broader range of PDI 0.121±0.011 on the average.While,CS/CEONE has smaller size of 49±4 nm and narrower PDI of 0.099±0.009.Both nanoemulsions had uniform spherical nanodroplets form and exhibited acidic nature.Fourier Transform Infrared Spectroscopy(FTIR)and UV-Visible Spectroscopy(UV-Vis)verified the successful incorporation of both CS and CEO within the nanoe-mulsion system.The results demonstrated a sustained and prolonged release profile from CS/CEONE for up to 4 days.The inhibitory effect of CEONE and CS/CEONE showed dose-dependent activity against mycelial growth of both fungi.CEONE and CS/CEONE at concentration 500µL/L exhibited the strongest inhibition with a sig-nificant(p<0.05)variation among them with value ranging from 56.11%to 71.94%and 52.2%to 79.2%,respec-tively.Comparing to control,CS/CEONE revealed the highest inhibitory effect against S.rolfsii after 96 h followed by CEONE with value reached 50.6%and 44.1%,respectively.The antifungal activity of the nanoemulsion showed strain–dependent behavior,where S.rolfsii was the most affected.SEM images showed changes in the hyphal structure of S.rolfsii and R.solani resulting from the impact of CEONE and CS/CEONE.Activity of pectinase and cellulase secreted by both fungi was also negatively affected by CEO,CEONE and CS/CEONE at all tested concentrations.Greenhouse trials revealed that increasing the concentrations of CEO,CEONE,and CS/CEONE from 50 to 500μL/L gradually increased their effectiveness in reducing the DI%and DS%of black scurf,stem canker,pre-damping off,and post-damping off diseases on potato.The results suggest that incorporation of CS to CEONE enhanced its activity and can be utilized as a secure and non-toxic nanocomposite.展开更多
文摘Powdery mildew of cucumber(Cucumis sativus L.)is a destructive disease caused by Podosphaera xanthii(Castagne)U.Braun&Shishkoff.This study aimed to investigate the antifungal effect of extracts of Ulva lactuca,Spirulina platensis,and Nostoc muscorum against P.xanthii and to improve the physiological and morphological traits of cucumber under commercial greenhouse conditions.The chemical composition of the individual extracts from U.lactuca,S.platensis,and N.muscorum was analyzed utilizing High-performance Liquid Chromatography(HPLC)and Gas Chromatography/Mass spectrometry(GC/MS).Cucumber plants were sprayed twice with 5%of the crude extracts of U.lactuca,S.platensis,and N.muscorum and their mixture(U.lactuca,S.platensis,and N.muscorum).The fungicide Topas 100 EC(Syngenta)was applied at the recommended dose(0.250 mL/L)only for comparison.The HPLC analysis indicated that the U.lactuca extract was the richest in phenolic compounds(605.84µg g^(−1)DW)compared to cyanobacterial extracts of S.platensis(214.77µg g^(−1)DW)and N.muscorum(462.97µg g^(−1)DW).The GC-MS spectrum analysis of methanolic extracts revealed 12 compounds in N.muscorum,11 compounds in S.platensis and 22 compounds in U.lactuca extract.In the 1st experiment,among treatments,the combined mixture(U.lactuca,S.platensis,and N.muscorum)and U.lactuca extract revealed the remarkable disease reduction attained 74.35%and 71.42%,respectively.However,the highest disease reduction was attributed to fungicide Topas 100 EC with value reached 85.28%.A similar pattern of results was also noted during the 2^(nd)experiment.In both experiments,the extract of S.platensis had the lowest effectiveness in lowering the DS and AUDPC of powdery mildew disease.The combined mixture and U.lactuca extract resulted in a substantial(p<0.05)increase in plant lengths,fresh and dry weights,leaves number,fruit number,and weight and yield/plant.Cucumber plants treated with either the extract of U.lactuca or the combined mixture exhibited the highest activity(0.084 and 0.088 U mL^(−1)min^(−1))for peroxidase and(1.64 and 1.62 U mL^(−1)min^(−1))for catalase,respectively,in the second experiment.The greatest increase in total phenolic content(7.97 mg g^(−1)FW)was noticed in plants following treatment with the combined mixture.The treatment with U.lactuca and S.platensis revealed a significant increase in carotenoids contents,reached up to 17.99 and 17.53 mg g^(−1)FW,respectively.We,therefore,support the need for considering sustainable management of powdery mildew of cucumber using the compounds derived from U.lactuca,S.platensis,and N.muscorum and to improve cucumber growth.
基金the National Research Centre,Egypt for supporting the project“Polymer nanocomposite and their applications in controlled release fertilizer and the health impacts of nanoparticles on rats”(project No.11090108)。
文摘The burning of agricultural waste is a major cause of environmental pollution.In this study,we sought to prepare biochar from agricultural waste as a source material for the preparation of carbon nanoparticles(CNPs).Surface morphology,hydrodynamic particle size,and purity and crystallinity of CNPs were extensively investigated using transmission electron microscopy(TEM),zeta sizing,and X-ray diffraction(XRD)spectroscopy,respectively.The CNPs were subsequently immersed in a solution of potassium nitrate(KNO_(3))to prepare a CNPs/NK nanocomposite(CNPs loaded with nitrogen(N)and potassium(K))as a nanocomposite fertilizer for common bean(Phaseolus vulgaris L.).The CNPs/NK nanocomposite was sprayed as a foliar fertilizer at 0,10,20,30,and 40 mg L^(-1)on common bean plants 25 d after sowing on a farm in Shebin El-Kom,El-Monifia,Egypt.The growth,yield,and quality of common bean were investigated during two successive growing seasons(2017 and 2018).The highest seed yields of 2.04 and 2.01 t ha^(-1)and the highest values of growth parameters including plant height of 61.5 and 59.2 cm,number of leaves per plant of 35 and 35,number of flowers per plant of 83.3 and 82.7,and plant fresh weight of 148.7 and 152.8 g plant^(-1)were obtained when using the CNPs/NK nanocomposite at a concentration of 20 mg L^(-1)during the 2017 and 2018 growing seasons,respectively.
文摘Subsistence farming,a form of cultivation in which almost all crops or livestock are used to maintain farms and the farm family,leaving little,surplus for sale and trade.Pre-industrial farming peoples all over the countries of the worldwide apply subsistence agriculture system and take advantage of the possibilities available to them from land and water resources in all locations of agriculture sites.The agricultural production has become more specialized and developed in the subsistence farming system,and farmers have produced abundant production from many horticulture crops that are traded among them and achieve their selfsufficiency from those crops.
基金This research was kindly funded by the Deanship of Scientific Research,Vice Presidency for Graduate Studies and Scientific Research,King Faisal University,Saudi Arabia,grant number(KFU241802).
文摘Rhizoctonia solani Kühn and Sclerotium rolfsii Sacc.are the primary soil-borne plant diseases responsible for sig-nificant reductions in global crop yields.The primary goal of this study was to investigate the antifungal potentials of clove essential oil(CEO),nanoemulsion form(CEONE)and chitosan/nanoemulsion nanocomposite(CS/CEONE)against R.solani and S.rolfsii through in vitro and in vivo trials.Both CEONE and CS/CEONE were prepared and investigated for their physical chemical and morphological characterization.The poisoned medium method was utilized to evaluate the inhibitory effects of CEO,CEONE and CS/CEONE on the mycelial growth and enzymatic activity of R.solani and S.rolfsii.The changes of hyphae of R.solani and S.rolfsii in response to treating with CEONE and CS/CEONE were observed with scanning electron microscope(SEM).The results revealed that CEONE have larger size 86±3 nm and a broader range of PDI 0.121±0.011 on the average.While,CS/CEONE has smaller size of 49±4 nm and narrower PDI of 0.099±0.009.Both nanoemulsions had uniform spherical nanodroplets form and exhibited acidic nature.Fourier Transform Infrared Spectroscopy(FTIR)and UV-Visible Spectroscopy(UV-Vis)verified the successful incorporation of both CS and CEO within the nanoe-mulsion system.The results demonstrated a sustained and prolonged release profile from CS/CEONE for up to 4 days.The inhibitory effect of CEONE and CS/CEONE showed dose-dependent activity against mycelial growth of both fungi.CEONE and CS/CEONE at concentration 500µL/L exhibited the strongest inhibition with a sig-nificant(p<0.05)variation among them with value ranging from 56.11%to 71.94%and 52.2%to 79.2%,respec-tively.Comparing to control,CS/CEONE revealed the highest inhibitory effect against S.rolfsii after 96 h followed by CEONE with value reached 50.6%and 44.1%,respectively.The antifungal activity of the nanoemulsion showed strain–dependent behavior,where S.rolfsii was the most affected.SEM images showed changes in the hyphal structure of S.rolfsii and R.solani resulting from the impact of CEONE and CS/CEONE.Activity of pectinase and cellulase secreted by both fungi was also negatively affected by CEO,CEONE and CS/CEONE at all tested concentrations.Greenhouse trials revealed that increasing the concentrations of CEO,CEONE,and CS/CEONE from 50 to 500μL/L gradually increased their effectiveness in reducing the DI%and DS%of black scurf,stem canker,pre-damping off,and post-damping off diseases on potato.The results suggest that incorporation of CS to CEONE enhanced its activity and can be utilized as a secure and non-toxic nanocomposite.
