Tomato brown rugose fruit virus(ToBRFV)causes severe fruit loss in tomato(Solanum lycopersicum)and pepper(Capsicum annuum)plants.It is an emerging Tobamovirus that is spreading globally.The major challenge is to devel...Tomato brown rugose fruit virus(ToBRFV)causes severe fruit loss in tomato(Solanum lycopersicum)and pepper(Capsicum annuum)plants.It is an emerging Tobamovirus that is spreading globally.The major challenge is to develop a reliable method for the detection of the virus,and to better characterize the symptoms it causes.The aims of this study,therefore,were to characterize the symptom development on tomato and pepper plants,and to establish a reliable detection method for the virus.Following infection of the tomato and pepper plants with ToBRFV,the leaves turned chlorotic,mosaic or mottled,while the fruit became rugose,necrotic and marbled,and showed discoloration with yellow or brown spots.Transmission electron microscopy(TEM)revealed single rod-like virus particles characteristic of the Tobamoviruses.Classical reverse transcription PCR(RT-PCR)and quantitative PCR(qPCR)with specific primers and probes confirmed that the virus is ToBRFV.We found that the resistance genes from tomato,Tm-2^(2),and pepper,L1,L2,L3 and L4,did not confer resistance to ToBRFV.Here,we present a PCR-based method as a diagnostic test for detecting ToBRFV in infected seeds.This method will help to prevent further spread of the virus in commercial seeds.展开更多
In the present study, a biofertilizer on the basis of Streptomyces fumanus gn-2 was used for the treatment of wheat and soybean seeds (dose 104 spore/ml) before planting them in soil with low fertility in order to det...In the present study, a biofertilizer on the basis of Streptomyces fumanus gn-2 was used for the treatment of wheat and soybean seeds (dose 104 spore/ml) before planting them in soil with low fertility in order to determine the effect of this biological agent on germination rate;the growth of seedlings, shoots, and the maturation phase of plants;the rhizosphere’s functional biodiversity;and the resistance of these plants to pathogens. Seeds were soaked in the suspension for a period of two or three hours. During the growing season of the crop, no additional fertilizing and spraying of a biopesticide against diseases or pests occurred. Despite the soil having low fertility, low quantities of organic matter, and not having been before used for the cultivation of agricultural plants, this biofertilizer showed a strong stimulatory effect on the growth of seeds and seedlings of wheat and soybeans. The average germination and seed vigor increased by 1.5 - 2.0 times, and the phenophases were accelerated to three to five days. In all phases of vegetation, the ammonifying bacteria in the presence of an antagonist (a biological agent) developed rapidly and were constantly present in significant numbers in the rhizosphere. Streptomyces fumanus introduced into non-sterile soil entered into competition with the local soil microflora and had the ability to colonize the rhizosphere system of plants. The use of a formulation of Streptomyces gn-2 has improved the composition of rhizosphere microflora, attracting saprophytic microorganisms: ammonificators and oligotrophs. The presence of the biocontrol microorganism Streptomyces fumanus in the rhizosphere plays an important role in enhancing the growth and development of useful groups, such as nitrogen-fixing bacteria.展开更多
Erwinia amylovora species were isolated from the blossoms, exudates, infected fruits, leaves and bent branches of diseased apple, pear and hawthorn trees, selected in the Chy, Osh and Jalal Abad regions. Biochemical a...Erwinia amylovora species were isolated from the blossoms, exudates, infected fruits, leaves and bent branches of diseased apple, pear and hawthorn trees, selected in the Chy, Osh and Jalal Abad regions. Biochemical and pathogenicity tests, alongside PCR analyses, were conducted to identify the local isolates of Erwinia amylovora. The alternative antagonistic microorganisms which combat bacterium E. amylovora were tested within in vitro and in vivo conditions. The results revealed the ability of Streptomyces antagonistic bacteria to decrease fire blight severity on pear and apple trees during the first stage of the fire blight disease in leaf tissues. Streptomyces strain C1-4 suppressed E. amylovora disease symptoms in the leaf tissues and excised apple and pear shoots. The incidence of fire blight on leaves was reduced by about 70% with two applications of bacterial antagonists. Further studies at different locations in Kyrgyzstan, using large scale application, would allow for stronger recommendations to be made, including studies and recommendations on their ability to prevent disease and to use them as main components in an integrated pest management program.展开更多
In the current study, we investigated the relationship between the abundance of carabid species (Coleoptera: Carabidae) and the phenological stages of weedy plants growing in edge habitats. A survey of carabid beetles...In the current study, we investigated the relationship between the abundance of carabid species (Coleoptera: Carabidae) and the phenological stages of weedy plants growing in edge habitats. A survey of carabid beetles was conducted in edge habitats between forest fragments and soybean/corn crops or orange orchards in five sites located in northeastern S?o Paulo state, Brazil, from November 2005 to May 2008. Beetles were captured with pitfall traps, and multiple regression analysis was used to determine the carabid species that prevailed on each of the phenological stages of weeds. In total, 1115 individuals, representing 26 genera and 52 species, were captured. Selenophorus species, mainly Selenophorus seriatoporus Putzeys, Selenophorus sp.4, Helluomorphoides squiresi (Chaudoir), Tetragonoderus laevigatus Chaudoir, Athrostictus sp.1 were abundant during the reproductive phenological stages of weedy plants, which suggests that these carabid species might prefer to feed on the seeds of weedy plants.展开更多
Applied experiments were conducted in the palm orchard in the Nubaria region. The orchard includes the varieties of Al-Barhi (imported) and Zaghloul (local) to examine the efficacy of some natural materials alone and ...Applied experiments were conducted in the palm orchard in the Nubaria region. The orchard includes the varieties of Al-Barhi (imported) and Zaghloul (local) to examine the efficacy of some natural materials alone and in combination with some pesticides against the Red Palm Weevil Rhynchophorus ferrugineus (RPW) that infects palm trees in Egypt. Most insects caught by light traps, which have a role in the spread of the red palm weevil in palm groves, appear in early February and March. Peak numbers for the month of May until September namely Phyllgnathus excavatus. Pseudophilus testaceus, Phonapata frontalis, and Oryctes elegans. The neglected gardens of date palms are more compensating for insect infestation than those maintained in terms of agricultural and pest control services. Individual injection of insecticide (Mosspilan) was the most potent against RPW-infested Barhi var. with a recovery rate of 91.7%, followed by Selikron at 80%, and finally Saydon at 37.5%. Injection of the car oil used with Mosspilan followed by Selikron was effective against RPW. No significant difference between treatments of injection (F-value: 1.2). Mixing injection of mineral oils with chemical pesticides is effective against red palm weevil after two successive seasons. As a result, the pesticide was poured around the affected palm root, with a low recovery rate. There is no effect of palm spray. The best way to control the red palm weevil is the method of injecting the tested material (single or mixed) with the pure pesticide into the trunk of the infected palm tree. The tested pesticide residues gradually decrease as the period after application is prolonged with an average loss of 0.12, 0.02 and 0.07 ppm after 90 consecutive days. .展开更多
Aspergillus spp. has been widely found as useful microorganism in biotechnology. They have a high ability in the production of secondary metabolites. Therefore, isolates of Aspergillus were isolated from healthy rice ...Aspergillus spp. has been widely found as useful microorganism in biotechnology. They have a high ability in the production of secondary metabolites. Therefore, isolates of Aspergillus were isolated from healthy rice field located in Selangor State/Malaysia. The obtained strain (UPMZ01) was conducted against Pyricularia oryzea by applying dual culture and culture filtrate technique. The antagonism of strain UPMZ01 in the dual culture was 81.326% inhibition percentage against P. oryzae given the optimum inhibitory percentage 100% at all concentration of secondary metabolites aged 14 days. The isolate (UPMZ01) was identified as Aspergillus niger with accession number (KY698415). The environment factors such as pH and temperature influencing on production of secondary metabolites. The results were shown that pH at level 5.0 and temperature between 21℃?to 29℃?is the optimum condition for A. niger to produce efficient antifungal metabolites which given 100% PIGR against blast pathogen. The secondary metabolites compounds were identified by Gas Chromatography-Mass Spectrometry (GC-MS). Fifteen compounds were recognized as major compounds which may have the possibility of possessing antifungal characteristics. Most of identified compounds are Oleic Acid, n-Hexadecanoic acid, Hexose, Glycerol, Stearic acid, Tetradecanoic acid, Dodecanoic acid and 5-Hydrxoymethylfurfural.展开更多
Detection of F. solani f. sp. cucurbitae causal agent of the crown and root rot disease of melon race 1, race 2 is difficult. It is based only on morphological characteristic. In this study, forty isolates identified ...Detection of F. solani f. sp. cucurbitae causal agent of the crown and root rot disease of melon race 1, race 2 is difficult. It is based only on morphological characteristic. In this study, forty isolates identified as Fusarium solani based on morphological characterization, F. solani was one of the most frequently isolated species. Molecular identification of these isolates by PCR technique using species-specific primer, indicated that thirty-two isolates, amplified product 580 bp (race 1) and two isolate amplified product 580 bp (race 2), while six isolates were not amplified with primer of both races. Production of Trichothecenes (T2-toxen, DON.) by Fusarium solani was conducted on isolates confirmed as belonging in the F. solani by PCR. The results indicated that the presence of Tri5, Tri13 genes is coding the ability of synthesis mycotoxin. In vitro, the results indicated that NPs (AgNPs, MgNPs) and chemical (Phylex) possess the antifungal properties against at various level. Treatment with (AgNPs 150 ppm, MgNPs 2%, 3% ppm) and 3% Phylex resulted in maximum inhabitation of F. solani . In vivo, five characters (height plant, hoot ant root fresh and dry weight) were measured based on the greenhouse, field experimental results. Treatment with (AgNPs, MgNPs) and Phylex had higher measured parameters than positive control.展开更多
Various bacterial species are known to be agents causing soft rot of potatoes. The results of this study showed that potato soft rot is widely spread in different potato planting areas in Jordan. A survey was conducte...Various bacterial species are known to be agents causing soft rot of potatoes. The results of this study showed that potato soft rot is widely spread in different potato planting areas in Jordan. A survey was conducted through the years 2013-2015 to detect potato soft rot disease in Jordan, two hundred and four rotted potato samples were collected from different potato growing areas through different potato growing seasons. One hundred and thirty one bacterial isolates were isolated, purified on selective media and identified as Pectobacterium carotovorum subspecies carotovorum (Pcc) by different biochemical and physiological tests. Furthermore, 131 Pcc Jordanian (Jo) isolates were identified by PCR analysis of total DNA extracted from isolates that were biochemically identified as Pcc using universal primer Fd1/Rd1. Cloning and sequencing of representative PCR products, amplifying the 16S rDNA region were done. Phylogenetic analysis of the Pcc Jo-isolates revealed other than 90% similarity with different reference Pcc strains available at the GenBank. Different rot causal agents also were detected by PCR amplification and further sequences. The sequencing data revealed similarities to Pseudomonas fluorescence, Enterobacteriaceae genera such as Enterobacter spp., Serratia spp. and Klebsiella spp., in addition to Pectobacterium carotovorum subsp. carotovorum. This study indicated that using molecular techniques such as amplification of 16S rDNA region is a sensitive and specific method for detecting Pcc as potato soft rot causal agent. So far this is the first study where Pcc has been identified by using PCR and sequencing approaches in Jordan.展开更多
The present research aimed at producing a biopesticide with proper formulation of invert emulsion (water-in-oil type) and effective strain of?Trichoderma harzianum?then, testing it against pathogens of postharvest mol...The present research aimed at producing a biopesticide with proper formulation of invert emulsion (water-in-oil type) and effective strain of?Trichoderma harzianum?then, testing it against pathogens of postharvest mold infections(Botrytis cinerea?&?Penicillium expansum) on fresh fruits of apple and pear. The?proper formulation of invert emulsion (IE#3) used for biopesticide production has the following ingredients (100% w/w): soybean oil (28.50%), coconut oil (19.50%), oil-soluble emulsifier: Tween 20 (2.0%), glycerine (4.25%), water-soluble emulsifier:?dehymuls k (0.75%),?sterile distilled water (22.5%) and conidial suspension of the effective strain ofT. harzianum?“TrichoPAL1” in water (22.5%, concentration 1 ×?107?conidia/ml). Testing efficacy of the produced biopesticide has indicated a significant reduction in the disease lesion diameter of mold infections on wounded apple and pear fruits stored at?20℃?± 1℃?compared to the untreated fruits or control (reduction from up to 38.75 to about 7.50 mm, respectively, according to?the type of mold infections and fruit type). Also, the treatment with the produced biopesticide has resulted in?a long protection period from mold infections on wounded and un-wounded fresh fruits of apple and pear stored under controlled and semi-commercial conditions(up to 2.5 months according to the type of mold infections and fruit type). In conclusion, the overall results have demonstrated the effectiveness of produced biopesticide on stored fruits under controlled and semi-commercial conditions therefore,?it is recommended to test this effectiveness on marketed fruits stored under variable conditions before applying it at a large scale.展开更多
Mud wasps are one of the most important problems that many archaeological sites suffer from in Egypt, especially in southern Egypt. Wasp’s growth increases, especially on the surface of stones or on mud-brick buildin...Mud wasps are one of the most important problems that many archaeological sites suffer from in Egypt, especially in southern Egypt. Wasp’s growth increases, especially on the surface of stones or on mud-brick buildings, which represents a major challenge to these archaeological sites. It works to hide the stone surfaces and archaeological inscriptions found on them in addition to that it works to damage the stone surfaces themselves through the nests that they build on these surfaces. It works on weakening the structure of sandstone and the study that included a study on mud wasps and Analysis of nests and studied through the use of various devices and methods, the damage and its nature have also been studied as a result of the presence of wasp nests and the reasons for their existence. Various treatment methods and the best appropriate methods for treating sandstone and stopping wasp activity have also been studied.展开更多
The local isolates of Trichoderma spp. and Fusarium solani were colected from citrus orchards in the Mekong delta of Vietnam and isolated on PDA, PDB and TSM medium for antagonism and Koch’s postulate testing. The re...The local isolates of Trichoderma spp. and Fusarium solani were colected from citrus orchards in the Mekong delta of Vietnam and isolated on PDA, PDB and TSM medium for antagonism and Koch’s postulate testing. The results showed that the high chitinolytic enzymes content of Trichoderma isolates can antagonise with Fusarium solani isolates by preventing the germination of Fusarium macroconidia in in-vitro condition. There are five promising isolates of Trichoderma spp. having high antagonism with Fusarium solani. These Trichoderma isolates also grew well in rice straws, maize stems, weeds and water hyacinth biowaste materials. These results supply the promising trend for biological control of root rot disease on citrus orchards of the Mekong delta.展开更多
Neozygites tanajoae is an entomopathogenic fungus which has been used for biocontrol of the cassava green mite(Mononychellus tanajoa,CGM)in Africa. Establishment and dispersal of Brazilian isolates which have been int...Neozygites tanajoae is an entomopathogenic fungus which has been used for biocontrol of the cassava green mite(Mononychellus tanajoa,CGM)in Africa. Establishment and dispersal of Brazilian isolates which have been introduced into some African countries in recent years to improve CGM control was followed with specific PCR assays.Two primer pairs,展开更多
In one of the field visits to cucurbits-growing areas in vicinity of Riyadh city during 2013-2015,severe virus disease-like symptoms were observed on watermelon in Al-Ammariyah area.Mechanical inoculation of the diffe...In one of the field visits to cucurbits-growing areas in vicinity of Riyadh city during 2013-2015,severe virus disease-like symptoms were observed on watermelon in Al-Ammariyah area.Mechanical inoculation of the different plant species used in the host range study,from the collected symptomatic watermelon samples,produced mosaic symptoms on Citrullus lanatus,Cucumis sativus,Cucurbita pepo,C.melo,C.melo subsp.melo and Nicotiana benthamiana,but chlorotic local lesions on Chenopodium amaranticolor.No symptoms were observed on the rest of the other inoculated plant species.The virus was transmitted by Aphis gossypii and A.craccivora in a non-persistent manner.Transmission electron microscopic examination of watermelon samples using the leaf dip method revealed only microscopic filamentous shaped virus particles measuring 750 nm in length and 12 nm in diameter in average.ELISA revealed positive results only to Watermelon mosaic virus(WMV)and negative to Zucchini yellow mosaic virus(ZYMV),Papaya ringspot virus(PRSV),Cucumber mosaic virus(CMV)and Squash mosaic virus(SqMV).Specific bands of approximately 825 bp were formed on agarose gel following electrophoresis of the reverse transcriptase-polymerase chain reaction(RT-PCR)products of each of the naturally infected C.lanatus,and artificially infected C.lanatus,C.pepo,C.sativus,and N.benthamiana.The homology tree that was constructed from multiple sequence alignments of the detected Saudi Arabian isolate of WMV(WMV-SA)with 18 other isolates of WMV from nine different countries indicated close relationships between them.Two isolates from Spain and two other isolates from Iran were more closely related to the WMV-SA whereas the isolate from Poland was the least.展开更多
All seven watermelon cultivars that were screened for their reactions to a severe Saudi Arabian isolate of Watermelon mosaic virus(WMV-SA)that was found inducing a severe disease in watermelon in Riyadh region,were fo...All seven watermelon cultivars that were screened for their reactions to a severe Saudi Arabian isolate of Watermelon mosaic virus(WMV-SA)that was found inducing a severe disease in watermelon in Riyadh region,were found to be susceptible and showed different virus-like symptoms upon mechanical inoculation.Sugar Baby,Crimson Sweet 1 and Crimson Sweet 2 cultivars showed milder symptoms and,therefore,got lower grand mean of weekly symptom ratings than Charleston Gray No.502,Jubilee,Black Diamond and Charleston Gray No.133 in both first and second experiments.Artificial inoculation with this isolate significantly reduced the plant height,fresh and dry weights of the tested cultivars.The reduction percentages in plant height of Sugar Baby and Crimson Sweet 2 were significantly lower than those of Crimson Sweet 1,Charleston Gray No.502 and Charleston Gray No.133 in both experiments.Also the reduction in percentages of fresh weights of Sugar Baby,Crimson Sweet 2 and Jubilee were significantly lower than reduction percentages of Crimson Sweet 1,Black Diamond and Charleston Gray No.133.The dry weight reduction percentages of Jubilee,Sugar Baby and Crimson Sweet 2 were lower than those of Charleston Gray No.502,Charleston Gray No.133,Black Diamond and Crimson Sweet 1 in both experiments.No correlation existed between the virus titer in the infected cultivars and their performances.In general,Sugar Baby and Crimson Sweet 2 performed better than the other cultivars as they had the lowest symptom severity ratings,the lowest percentages of plant height,fresh and dry weight reductions compared to the other tested cultivars.展开更多
文摘Tomato brown rugose fruit virus(ToBRFV)causes severe fruit loss in tomato(Solanum lycopersicum)and pepper(Capsicum annuum)plants.It is an emerging Tobamovirus that is spreading globally.The major challenge is to develop a reliable method for the detection of the virus,and to better characterize the symptoms it causes.The aims of this study,therefore,were to characterize the symptom development on tomato and pepper plants,and to establish a reliable detection method for the virus.Following infection of the tomato and pepper plants with ToBRFV,the leaves turned chlorotic,mosaic or mottled,while the fruit became rugose,necrotic and marbled,and showed discoloration with yellow or brown spots.Transmission electron microscopy(TEM)revealed single rod-like virus particles characteristic of the Tobamoviruses.Classical reverse transcription PCR(RT-PCR)and quantitative PCR(qPCR)with specific primers and probes confirmed that the virus is ToBRFV.We found that the resistance genes from tomato,Tm-2^(2),and pepper,L1,L2,L3 and L4,did not confer resistance to ToBRFV.Here,we present a PCR-based method as a diagnostic test for detecting ToBRFV in infected seeds.This method will help to prevent further spread of the virus in commercial seeds.
文摘In the present study, a biofertilizer on the basis of Streptomyces fumanus gn-2 was used for the treatment of wheat and soybean seeds (dose 104 spore/ml) before planting them in soil with low fertility in order to determine the effect of this biological agent on germination rate;the growth of seedlings, shoots, and the maturation phase of plants;the rhizosphere’s functional biodiversity;and the resistance of these plants to pathogens. Seeds were soaked in the suspension for a period of two or three hours. During the growing season of the crop, no additional fertilizing and spraying of a biopesticide against diseases or pests occurred. Despite the soil having low fertility, low quantities of organic matter, and not having been before used for the cultivation of agricultural plants, this biofertilizer showed a strong stimulatory effect on the growth of seeds and seedlings of wheat and soybeans. The average germination and seed vigor increased by 1.5 - 2.0 times, and the phenophases were accelerated to three to five days. In all phases of vegetation, the ammonifying bacteria in the presence of an antagonist (a biological agent) developed rapidly and were constantly present in significant numbers in the rhizosphere. Streptomyces fumanus introduced into non-sterile soil entered into competition with the local soil microflora and had the ability to colonize the rhizosphere system of plants. The use of a formulation of Streptomyces gn-2 has improved the composition of rhizosphere microflora, attracting saprophytic microorganisms: ammonificators and oligotrophs. The presence of the biocontrol microorganism Streptomyces fumanus in the rhizosphere plays an important role in enhancing the growth and development of useful groups, such as nitrogen-fixing bacteria.
文摘Erwinia amylovora species were isolated from the blossoms, exudates, infected fruits, leaves and bent branches of diseased apple, pear and hawthorn trees, selected in the Chy, Osh and Jalal Abad regions. Biochemical and pathogenicity tests, alongside PCR analyses, were conducted to identify the local isolates of Erwinia amylovora. The alternative antagonistic microorganisms which combat bacterium E. amylovora were tested within in vitro and in vivo conditions. The results revealed the ability of Streptomyces antagonistic bacteria to decrease fire blight severity on pear and apple trees during the first stage of the fire blight disease in leaf tissues. Streptomyces strain C1-4 suppressed E. amylovora disease symptoms in the leaf tissues and excised apple and pear shoots. The incidence of fire blight on leaves was reduced by about 70% with two applications of bacterial antagonists. Further studies at different locations in Kyrgyzstan, using large scale application, would allow for stronger recommendations to be made, including studies and recommendations on their ability to prevent disease and to use them as main components in an integrated pest management program.
文摘In the current study, we investigated the relationship between the abundance of carabid species (Coleoptera: Carabidae) and the phenological stages of weedy plants growing in edge habitats. A survey of carabid beetles was conducted in edge habitats between forest fragments and soybean/corn crops or orange orchards in five sites located in northeastern S?o Paulo state, Brazil, from November 2005 to May 2008. Beetles were captured with pitfall traps, and multiple regression analysis was used to determine the carabid species that prevailed on each of the phenological stages of weeds. In total, 1115 individuals, representing 26 genera and 52 species, were captured. Selenophorus species, mainly Selenophorus seriatoporus Putzeys, Selenophorus sp.4, Helluomorphoides squiresi (Chaudoir), Tetragonoderus laevigatus Chaudoir, Athrostictus sp.1 were abundant during the reproductive phenological stages of weedy plants, which suggests that these carabid species might prefer to feed on the seeds of weedy plants.
文摘Applied experiments were conducted in the palm orchard in the Nubaria region. The orchard includes the varieties of Al-Barhi (imported) and Zaghloul (local) to examine the efficacy of some natural materials alone and in combination with some pesticides against the Red Palm Weevil Rhynchophorus ferrugineus (RPW) that infects palm trees in Egypt. Most insects caught by light traps, which have a role in the spread of the red palm weevil in palm groves, appear in early February and March. Peak numbers for the month of May until September namely Phyllgnathus excavatus. Pseudophilus testaceus, Phonapata frontalis, and Oryctes elegans. The neglected gardens of date palms are more compensating for insect infestation than those maintained in terms of agricultural and pest control services. Individual injection of insecticide (Mosspilan) was the most potent against RPW-infested Barhi var. with a recovery rate of 91.7%, followed by Selikron at 80%, and finally Saydon at 37.5%. Injection of the car oil used with Mosspilan followed by Selikron was effective against RPW. No significant difference between treatments of injection (F-value: 1.2). Mixing injection of mineral oils with chemical pesticides is effective against red palm weevil after two successive seasons. As a result, the pesticide was poured around the affected palm root, with a low recovery rate. There is no effect of palm spray. The best way to control the red palm weevil is the method of injecting the tested material (single or mixed) with the pure pesticide into the trunk of the infected palm tree. The tested pesticide residues gradually decrease as the period after application is prolonged with an average loss of 0.12, 0.02 and 0.07 ppm after 90 consecutive days. .
文摘Aspergillus spp. has been widely found as useful microorganism in biotechnology. They have a high ability in the production of secondary metabolites. Therefore, isolates of Aspergillus were isolated from healthy rice field located in Selangor State/Malaysia. The obtained strain (UPMZ01) was conducted against Pyricularia oryzea by applying dual culture and culture filtrate technique. The antagonism of strain UPMZ01 in the dual culture was 81.326% inhibition percentage against P. oryzae given the optimum inhibitory percentage 100% at all concentration of secondary metabolites aged 14 days. The isolate (UPMZ01) was identified as Aspergillus niger with accession number (KY698415). The environment factors such as pH and temperature influencing on production of secondary metabolites. The results were shown that pH at level 5.0 and temperature between 21℃?to 29℃?is the optimum condition for A. niger to produce efficient antifungal metabolites which given 100% PIGR against blast pathogen. The secondary metabolites compounds were identified by Gas Chromatography-Mass Spectrometry (GC-MS). Fifteen compounds were recognized as major compounds which may have the possibility of possessing antifungal characteristics. Most of identified compounds are Oleic Acid, n-Hexadecanoic acid, Hexose, Glycerol, Stearic acid, Tetradecanoic acid, Dodecanoic acid and 5-Hydrxoymethylfurfural.
文摘Detection of F. solani f. sp. cucurbitae causal agent of the crown and root rot disease of melon race 1, race 2 is difficult. It is based only on morphological characteristic. In this study, forty isolates identified as Fusarium solani based on morphological characterization, F. solani was one of the most frequently isolated species. Molecular identification of these isolates by PCR technique using species-specific primer, indicated that thirty-two isolates, amplified product 580 bp (race 1) and two isolate amplified product 580 bp (race 2), while six isolates were not amplified with primer of both races. Production of Trichothecenes (T2-toxen, DON.) by Fusarium solani was conducted on isolates confirmed as belonging in the F. solani by PCR. The results indicated that the presence of Tri5, Tri13 genes is coding the ability of synthesis mycotoxin. In vitro, the results indicated that NPs (AgNPs, MgNPs) and chemical (Phylex) possess the antifungal properties against at various level. Treatment with (AgNPs 150 ppm, MgNPs 2%, 3% ppm) and 3% Phylex resulted in maximum inhabitation of F. solani . In vivo, five characters (height plant, hoot ant root fresh and dry weight) were measured based on the greenhouse, field experimental results. Treatment with (AgNPs, MgNPs) and Phylex had higher measured parameters than positive control.
文摘Various bacterial species are known to be agents causing soft rot of potatoes. The results of this study showed that potato soft rot is widely spread in different potato planting areas in Jordan. A survey was conducted through the years 2013-2015 to detect potato soft rot disease in Jordan, two hundred and four rotted potato samples were collected from different potato growing areas through different potato growing seasons. One hundred and thirty one bacterial isolates were isolated, purified on selective media and identified as Pectobacterium carotovorum subspecies carotovorum (Pcc) by different biochemical and physiological tests. Furthermore, 131 Pcc Jordanian (Jo) isolates were identified by PCR analysis of total DNA extracted from isolates that were biochemically identified as Pcc using universal primer Fd1/Rd1. Cloning and sequencing of representative PCR products, amplifying the 16S rDNA region were done. Phylogenetic analysis of the Pcc Jo-isolates revealed other than 90% similarity with different reference Pcc strains available at the GenBank. Different rot causal agents also were detected by PCR amplification and further sequences. The sequencing data revealed similarities to Pseudomonas fluorescence, Enterobacteriaceae genera such as Enterobacter spp., Serratia spp. and Klebsiella spp., in addition to Pectobacterium carotovorum subsp. carotovorum. This study indicated that using molecular techniques such as amplification of 16S rDNA region is a sensitive and specific method for detecting Pcc as potato soft rot causal agent. So far this is the first study where Pcc has been identified by using PCR and sequencing approaches in Jordan.
文摘The present research aimed at producing a biopesticide with proper formulation of invert emulsion (water-in-oil type) and effective strain of?Trichoderma harzianum?then, testing it against pathogens of postharvest mold infections(Botrytis cinerea?&?Penicillium expansum) on fresh fruits of apple and pear. The?proper formulation of invert emulsion (IE#3) used for biopesticide production has the following ingredients (100% w/w): soybean oil (28.50%), coconut oil (19.50%), oil-soluble emulsifier: Tween 20 (2.0%), glycerine (4.25%), water-soluble emulsifier:?dehymuls k (0.75%),?sterile distilled water (22.5%) and conidial suspension of the effective strain ofT. harzianum?“TrichoPAL1” in water (22.5%, concentration 1 ×?107?conidia/ml). Testing efficacy of the produced biopesticide has indicated a significant reduction in the disease lesion diameter of mold infections on wounded apple and pear fruits stored at?20℃?± 1℃?compared to the untreated fruits or control (reduction from up to 38.75 to about 7.50 mm, respectively, according to?the type of mold infections and fruit type). Also, the treatment with the produced biopesticide has resulted in?a long protection period from mold infections on wounded and un-wounded fresh fruits of apple and pear stored under controlled and semi-commercial conditions(up to 2.5 months according to the type of mold infections and fruit type). In conclusion, the overall results have demonstrated the effectiveness of produced biopesticide on stored fruits under controlled and semi-commercial conditions therefore,?it is recommended to test this effectiveness on marketed fruits stored under variable conditions before applying it at a large scale.
文摘Mud wasps are one of the most important problems that many archaeological sites suffer from in Egypt, especially in southern Egypt. Wasp’s growth increases, especially on the surface of stones or on mud-brick buildings, which represents a major challenge to these archaeological sites. It works to hide the stone surfaces and archaeological inscriptions found on them in addition to that it works to damage the stone surfaces themselves through the nests that they build on these surfaces. It works on weakening the structure of sandstone and the study that included a study on mud wasps and Analysis of nests and studied through the use of various devices and methods, the damage and its nature have also been studied as a result of the presence of wasp nests and the reasons for their existence. Various treatment methods and the best appropriate methods for treating sandstone and stopping wasp activity have also been studied.
文摘The local isolates of Trichoderma spp. and Fusarium solani were colected from citrus orchards in the Mekong delta of Vietnam and isolated on PDA, PDB and TSM medium for antagonism and Koch’s postulate testing. The results showed that the high chitinolytic enzymes content of Trichoderma isolates can antagonise with Fusarium solani isolates by preventing the germination of Fusarium macroconidia in in-vitro condition. There are five promising isolates of Trichoderma spp. having high antagonism with Fusarium solani. These Trichoderma isolates also grew well in rice straws, maize stems, weeds and water hyacinth biowaste materials. These results supply the promising trend for biological control of root rot disease on citrus orchards of the Mekong delta.
文摘Neozygites tanajoae is an entomopathogenic fungus which has been used for biocontrol of the cassava green mite(Mononychellus tanajoa,CGM)in Africa. Establishment and dispersal of Brazilian isolates which have been introduced into some African countries in recent years to improve CGM control was followed with specific PCR assays.Two primer pairs,
文摘In one of the field visits to cucurbits-growing areas in vicinity of Riyadh city during 2013-2015,severe virus disease-like symptoms were observed on watermelon in Al-Ammariyah area.Mechanical inoculation of the different plant species used in the host range study,from the collected symptomatic watermelon samples,produced mosaic symptoms on Citrullus lanatus,Cucumis sativus,Cucurbita pepo,C.melo,C.melo subsp.melo and Nicotiana benthamiana,but chlorotic local lesions on Chenopodium amaranticolor.No symptoms were observed on the rest of the other inoculated plant species.The virus was transmitted by Aphis gossypii and A.craccivora in a non-persistent manner.Transmission electron microscopic examination of watermelon samples using the leaf dip method revealed only microscopic filamentous shaped virus particles measuring 750 nm in length and 12 nm in diameter in average.ELISA revealed positive results only to Watermelon mosaic virus(WMV)and negative to Zucchini yellow mosaic virus(ZYMV),Papaya ringspot virus(PRSV),Cucumber mosaic virus(CMV)and Squash mosaic virus(SqMV).Specific bands of approximately 825 bp were formed on agarose gel following electrophoresis of the reverse transcriptase-polymerase chain reaction(RT-PCR)products of each of the naturally infected C.lanatus,and artificially infected C.lanatus,C.pepo,C.sativus,and N.benthamiana.The homology tree that was constructed from multiple sequence alignments of the detected Saudi Arabian isolate of WMV(WMV-SA)with 18 other isolates of WMV from nine different countries indicated close relationships between them.Two isolates from Spain and two other isolates from Iran were more closely related to the WMV-SA whereas the isolate from Poland was the least.
文摘All seven watermelon cultivars that were screened for their reactions to a severe Saudi Arabian isolate of Watermelon mosaic virus(WMV-SA)that was found inducing a severe disease in watermelon in Riyadh region,were found to be susceptible and showed different virus-like symptoms upon mechanical inoculation.Sugar Baby,Crimson Sweet 1 and Crimson Sweet 2 cultivars showed milder symptoms and,therefore,got lower grand mean of weekly symptom ratings than Charleston Gray No.502,Jubilee,Black Diamond and Charleston Gray No.133 in both first and second experiments.Artificial inoculation with this isolate significantly reduced the plant height,fresh and dry weights of the tested cultivars.The reduction percentages in plant height of Sugar Baby and Crimson Sweet 2 were significantly lower than those of Crimson Sweet 1,Charleston Gray No.502 and Charleston Gray No.133 in both experiments.Also the reduction in percentages of fresh weights of Sugar Baby,Crimson Sweet 2 and Jubilee were significantly lower than reduction percentages of Crimson Sweet 1,Black Diamond and Charleston Gray No.133.The dry weight reduction percentages of Jubilee,Sugar Baby and Crimson Sweet 2 were lower than those of Charleston Gray No.502,Charleston Gray No.133,Black Diamond and Crimson Sweet 1 in both experiments.No correlation existed between the virus titer in the infected cultivars and their performances.In general,Sugar Baby and Crimson Sweet 2 performed better than the other cultivars as they had the lowest symptom severity ratings,the lowest percentages of plant height,fresh and dry weight reductions compared to the other tested cultivars.