Antifungal activity of four plant extracts against Botrytis cinerea

Botrytis cinerea, responsible for the gray mold disease of tomato, is one of the main problems in fruit exporting countries. Synthetic antifungals are used for their control. However, these products lead to serious damage to environment ant human. Furthermore, it has developed a resistance towards many of them. Therefore, the use of botanical biopesticides as natural alternatives that are friendly to the environment has increased in the last decade. The objective of the present study is the evaluation of the antifungal activity of extracts of four plants, Marrubium vulgare, Moringa oleifera, Psidium guajava and Casimiroa edulis against B. cinerea and the phytochemical characterization of these extracts. The extraction was carried out by maceration, decoction, and ultrasonic-assisted extraction. The high extraction yields of 18.91%, 31.05%, 33.01% and 24.67% were obtained respectively with maceration for M. vulgare, M. oleifera, P. guajava and C. edulis. Qualitative phytochemical tests revealed the presence of terpenoids in all extracts, while saponosides were present only in a few extracts. The highest contents of polyphenols were noted for P. guajava and C. edulis. Also, the highest flavonoid content was noted for C. edulis and M. oleifera. The evaluation of the activity of the studied extracts against the mycelial growth and the germination of the spores of B. cinerea showed that the extracts obtained by maceration and by ultrasonic-assisted extraction of P. guajava and C. edulis are the most efficient against the mycelial growth with an inhibition percentage of 100% for all the tested concentrations. Similarly, the maceration extract of M. vulgare allowed the total inhibition of the germination of the pathogen spores. Finally, the extracts of M. oleifera were the least effective against B. cinerea

Inoculation of tomato plants with rhizobacteria suppresses development of whitefly Bemisia tabaci (GENNADIUS) (HEMIPTERA: ALEYRODIDAE): Agro-ecological application.

In agroecosystems, soil biodiversity is increasingly becoming more recognized as providing benefits to both plants and human health. It performs a wide variety of ecological services beyond the recycling of nutrients to plant growth and manage pests and diseases below the economic injury level. This study investigated the effects of three Pseudomonas isolates (Q172B, Q110B and Q036B), isolated from untreated tomato rhizospheric soil, as a biological control agent of Bemisia tabaci which is a key pest of tomato crops. The study was conducted under laboratory and glasshouse conditions and the water treatment was used as a control. Adult mortality rates were assessed during three days at 24h interval and larva mortality rates were evaluated during six days after treatment at 48h interval. Results indicate that Q036B isolate has a faster effect on B. tabaci adult and larvae. Under laboratory conditions, all three Pseudomonas isolates (Q110B, Q036B and Q172B) have a significant effect on B. tabaci adult mortality compared to control. The earliest and the most important mortality rate of 76% was recorded by Q036B. Two isolates Q036B and Q110B caused a significant mortality on B. tabaci larvae; with highest mortality effect (79%) was observed for Q036B compared to control. However, Q172B has no mortality effects on B. tabaci larvae under laboratory conditions. In glasshouse conditions, only Q036B provided high mortality rates of 91% at 168h after treatment. The results of this study indicate that the Pseudomonas isolate Q036B significantly suppresses B. tabaci in tomato plant and could substitute the excessive use of chemicals. Current research indicates that soil biodiversity could be promising to preserve agro-ecological sustainability

Activité antifongique de quatre extraits de plantes contre Botrytis cinerea

Botrytis cinerea, responsible for the gray mold disease of tomato, is one of the main problems in fruit exporting countries. Synthetic antifungals are used for their control. However, these products lead to serious damage to environment ant human. Furthermore, it has developed a resistance towards many of them. Therefore, the use of botanical biopesticides as natural alternatives that are friendly to the environment has increased in the last decade. The objective of the present study is the evaluation of the antifungal activity of extracts of four plants, Marrubium vulgare, Moringa oleifera, Psidium guajava and Casimiroa edulis against B. cinerea and the phytochemical characterization of these extracts. The extraction was carried out by maceration, decoction, and ultrasonic-assisted extraction. The high extraction yields of 18.91%, 31.05%, 33.01% and 24.67% were obtained respectively with maceration for M. vulgare, M. oleifera, P. guajava and C. edulis. Qualitative phytochemical tests revealed the presence of terpenoids in all extracts, while saponosides were present only in a few extracts. The highest contents of polyphenols were noted for P. guajava and C. edulis. Also, the highest flavonoid content was noted for C. edulis and M. oleifera. The evaluation of the activity of the studied extracts against the mycelial growth and the germination of the spores of B. cinerea showed that the extracts obtained by maceration and by ultrasonic-assisted extraction of P. guajava and C. edulis are the most efficient against the mycelial growth with an inhibition percentage of 100% for all the tested concentrations. Similarly, the maceration extract of M. vulgare allowed the total inhibition of the germination of the pathogen spores. Finally, the extracts of M. oleifera were the least effective against B. cinerea.Botrytis cinerea, responsable de la moisissure grise de la tomate, est le principal problème des pays exportateurs de fruits. Des antifongiques synthétiques sont utilisés pour leur contrôle. Cependant, ces produits entraînent de graves dommages à l'environnement et à la santé humaine. En outre, il a développé une résistance à l’encontre de nombre de pesticides. Par conséquent, l’utilisation de biopesticides botaniques comme alternatives naturelles et respectueuses de l’environnement a augmenté au cours de la dernière décennie. L'objectif de la présente étude est l'évaluation de l'activité antifongique des extraits de quatre plantes, Marrubium vulgare, Moringa oleifera, Psidium guajava et Casimiroa edulis contre B. cinerea et la caractérisation phytochimique de ces extraits. L'extraction a été réalisée par macération, décoction et extraction assistée par ultrasons. Les rendements d'extraction les plus élevés ont été obtenus respectivement avec macération pour M. vulgare (18,91%), M. oleifera (31,05%), P. guajava (33,01%) et C. edulis (24,67%). Des tests phytochimiques qualitatifs ont révélé la présence de terpénoïdes dans tous les extraits, tandis que les saponosides n'étaient présents que dans quelques extraits. Les teneurs les plus élevées en polyphénols ont été notées pour P. guajava et C. edulis. En outre, la teneur en flavonoïdes la plus élevée a été obtenu chez C. edulis et M. oleifera. L'évaluation de l'activité des extraits étudiés contre la croissance mycélienne et la germination des spores de B. cinerea a montré que les extraits obtenus par macération et par extraction assistée par ultrasons de P. guajava et C. edulis sont les plus efficaces contre la croissance mycélienne avec un pourcentage d'inhibition de 100% pour toutes les concentrations testées. De même, l'extrait de macération de M. vulgare a permis l'inhibition totale de la germination des spores de cet agent pathogène. Enfin, les extraits de M. oleifera sont les moins efficaces contre B. cinerea

Activité antifongique de quatre extraits de plantes contre Botrytis cinerea

Botrytis cinerea, responsible for the gray mold disease of tomato, is one of the main problems in fruit exporting countries. Synthetic antifungals are used for their control. However, these products lead to serious damage to environment ant human. Furthermore, it has developed a resistance towards many of them. Therefore, the use of botanical biopesticides as natural alternatives that are friendly to the environment has increased in the last decade. The objective of the present study is the evaluation of the antifungal activity of extracts of four plants, Marrubium vulgare, Moringa oleifera, Psidium guajava and Casimiroa edulis against B. cinerea and the phytochemical characterization of these extracts. The extraction was carried out by maceration, decoction, and ultrasonic-assisted extraction. The high extraction yields of 18.91%, 31.05%, 33.01% and 24.67% were obtained respectively with maceration for M. vulgare, M. oleifera, P. guajava and C. edulis. Qualitative phytochemical tests revealed the presence of terpenoids in all extracts, while saponosides were present only in a few extracts. The highest contents of polyphenols were noted for P. guajava and C. edulis. Also, the highest flavonoid content was noted for C. edulis and M. oleifera. The evaluation of the activity of the studied extracts against the mycelial growth and the germination of the spores of B. cinerea showed that the extracts obtained by maceration and by ultrasonic-assisted extraction of P. guajava and C. edulis are the most efficient against the mycelial growth with an inhibition percentage of 100% for all the tested concentrations. Similarly, the maceration extract of M. vulgare allowed the total inhibition of the germination of the pathogen spores. Finally, the extracts of M. oleifera were the least effective against B. cinerea.Botrytis cinerea, responsable de la moisissure grise de la tomate, est le principal problème des pays exportateurs de fruits. Des antifongiques synthétiques sont utilisés pour leur contrôle. Cependant, ces produits entraînent de graves dommages à l'environnement et à la santé humaine. En outre, il a développé une résistance à l’encontre de nombre de pesticides. Par conséquent, l’utilisation de biopesticides botaniques comme alternatives naturelles et respectueuses de l’environnement a augmenté au cours de la dernière décennie. L'objectif de la présente étude est l'évaluation de l'activité antifongique des extraits de quatre plantes, Marrubium vulgare, Moringa oleifera, Psidium guajava et Casimiroa edulis contre B. cinerea et la caractérisation phytochimique de ces extraits. L'extraction a été réalisée par macération, décoction et extraction assistée par ultrasons. Les rendements d'extraction les plus élevés ont été obtenus respectivement avec macération pour M. vulgare (18,91%), M. oleifera (31,05%), P. guajava (33,01%) et C. edulis (24,67%). Des tests phytochimiques qualitatifs ont révélé la présence de terpénoïdes dans tous les extraits, tandis que les saponosides n'étaient présents que dans quelques extraits. Les teneurs les plus élevées en polyphénols ont été notées pour P. guajava et C. edulis. En outre, la teneur en flavonoïdes la plus élevée a été obtenu chez C. edulis et M. oleifera. L'évaluation de l'activité des extraits étudiés contre la croissance mycélienne et la germination des spores de B. cinerea a montré que les extraits obtenus par macération et par extraction assistée par ultrasons de P. guajava et C. edulis sont les plus efficaces contre la croissance mycélienne avec un pourcentage d'inhibition de 100% pour toutes les concentrations testées. De même, l'extrait de macération de M. vulgare a permis l'inhibition totale de la germination des spores de cet agent pathogène. Enfin, les extraits de M. oleifera sont les moins efficaces contre B. cinerea

Terrestrial arthropods diversity in the Argan Biosphere Reserve: Seasonal dynamics and ecological function roles

Diversity, spatial patterns and temporal trends of terrestrial arthropod communities in the Arganeraie Biosphere Reserve of Morocco are poorly understood. Arthropods were seasonally sampled using pitfall traps at four sites, three of which are Argan forest ecosystem and one of which is a modern Argan grove. Diversity parameters were seasonally measured. Observation allowed identification of 161 morphospecies belonging to the five classes Chilopoda, Malacostraca, Collembola, Insecta and Arachnida were recorded. Captures were dominated by insects, representing more than 90% of the total trapped individuals. Insecta were the most diversified class (122 morphospecies), followed by Arachnida (33). The three other classes were less diversified with two species each. Among insects, Coleoptera and Hymenoptera were the most diversified groups. Diversity parameters exhibited seasonal variations. The highest arthropod abundance per sample was recorded during spring, while observed richness was higher in spring and summer. Shannon diversity index showed no significant difference among seasons. The composition of terrestrial arthropod communities between sites changed among seasons. A high dissimilarity was reported between the terrestrial arthropod community of Belfaa and those of other sites. The classification of arthropods into trophic guilds shows the importance of both predators and detritivores, which shows a higher abundance in spring and summer. Overall, predators guild richness was higher than others among seasons. This study highlights spatiotemporal diversity composition and structure of terrestrial arthropods community associated with the Argan ecosystem, complementing the unique diversity and proliferation of ecotypes present in Morocco

Ecological applications of Pseudomonas as a biopesticide to control two-spotted mite Tetranychus urticae: chitinase and HCN production

The two-spotted spider mite (Tetranychus urticae Koch) is an important pest of many horticultural crops. A study was conducted to evaluate the effect of three fluorescent Pseudomonas isolates obtained from rhizospheric soil of tomato (Solanum lycopersicon) in Agadir, Morocco: Q110B, Q036B and Q172B, as potential biological control agents for T. urticae. Both acaricide and repellent activities were assessed on homogenous adult mites. The acaricidal activity test evaluated five concentrations of bacterial suspensions: 0 (control), 102, 104, 106, 108, and 1010 cfu ⋅ ml–1, while only the 1010 cfu ∙ ml−1 concentration of each bacterium was used for the repellent bioassay. The mortality rate and repellentindex were recorded 24, 48 and 72 h after application. Results indicated that the survival rate of T. urticae was reduced (p ≤ 0.01) by all three bacterial isolates compared to control. Within the 24–72 h time period the mortality rates ranged from 8 to 87%, 16 to 99%, and 13 to 89%, for Q110B, Q036B and Q172B isolates, respectively. The isolate Q036B (LC50 = 0.598 cfu ⋅ ml–1) provided higher mortality rates than Q172B and Q110B with LC50 values of 90,846 and 169,585 cfu ⋅ ml–1, respectively. Repellent activity was also the highest with Pseudomonas Q036B having a 71% repellence index at 48 h after application. Regarding the mechanism of action, all three isolates produced hydrogen cyanide, and exhibited protease and cellulose activities, although only Q036B and Q172B had potential chitinase action. Identification analysis showed that the isolates were either Pseudomonas putida (Q172B) or P. fluorescens (Q110B and Q036B). Our results indicate that the P. fluorescens isolate Q036B is a promising candidate for biological control of T. urticae, and has potential to contribute to an integrated pest management program to control this important pest. Then the fruits produced will be qualified as safe for consumers and the environment. The present work was customized to give support for policy decision makers as an agroecological potential meeting needs of industries and ecological balance