Management of Strawberry Grey Mold Disease Using Biocontrol Agents and Plant Extracts

Strawberry (Fragaria × ananassa Duch.) is a significant global soft fruit crop, prized for its nutrient content and pleasant flavor. However, diseases, particularly grey mold caused by Botrytis cinerea Pers. Fr. poses major constraints to strawberry production and productivity. Grey mold severely impacts fruit quality and quantity, diminishing market value. This study evaluated five B. cinerea isolates from various locations in the Ri-Bhoi district of Meghalaya. All isolates were pathogenic, with isolate SGM 2 identified as highly virulent. Host range studies showed the pathogen-producing symptoms in the fava bean pods, marigold, gerbera, and chrysanthemum flowers and in the fava bean, gerbera, and lettuce leaves. In vitro tests revealed that neem extract (15% w/v) achieved the highest mycelial growth inhibition at 76.66%, while black turmeric extract (5% w/v) had the lowest inhibition at 9.62%. Dual culture methods with bio-control agents indicated that Bacillus subtilis recorded the highest mean inhibition at 77.03%, while Pseudomonas fluorescens had the lowest at 20.36% against the two virulent isolates. Pot evaluations demonstrated that B. subtilis resulted in the lowest percent disease index at 20.59%, followed by neem extract at 23.31%, with the highest disease index in the control group at 42.51%. Additionally, B. subtilis significantly improved plant growth, yielding an average of 0.32 kg compared to 0.14 kg in the control. The promising results of B. subtilis and neem leaf extract from this study suggest their potential for eco-friendly managing grey mold in strawberries under field conditions.

Assessing the Efficacy of Lemongrass (Cymbopogon citratus) and Sambong (Blumea balsamifera) Extracts in Combating Black Pod Disease: Sustainable Solutions for Controlling Phytophthora megakarya in Cameroon’s Cocoa Plantations

The use of plant extracts as antifungal agents is gaining increasing attention, particularly for the control of black pod disease in cocoa. Despite extensive research, current strategies haven’t been entirely effective. This study evaluated the effectiveness of Cymbopogon citratus and Blumea balsamifora leaf extracts, both individually and in combination, against Phytophthora megakarya. We assessed the efficacy of the most promising combination (75% B. balsamifera, 25% C. citratus) after storage at room temperature for up to 9 days. Agar microdilution and in vivo bioassays were conducted to determine antifungal susceptibility and effectiveness. Blumea extract exhibited the highest overall inhibitory activity, with the lowest minimum inhibitory concentration (117 µl mL−1) while C. citratus had a narrower range of MIC (146 to 233 µl mL−1). The combination of C. citratus and B. balsamifera demonstrated a synergistic effect against P. megakarya, achieving growth inhibition on V8 media (92.72 ± 4.20% to 100%) and on artificially infected detached pod cortex (92.24 ± 4.53% to 98.75 ± 1.25%), which was not significantly different from the positive control (Ridomil). Furthermore, this combination maintained its effectiveness for up to 9 days at room temperature. These findings suggest that combining plant extracts can enhance their antifungal properties.

Larvicidal and repellent activity of medicinal plant extracts from Eastern Ghats of South India against malaria and filariasis vectors

Objective:To evaluate the larvicidal and repellent activities of ethyl acetate and methanol extracts of Acacia concinna（A.concinna）,Cassia siamea（C.siamea）.Conundrum sativum（C. sativum）,Cuminum cyminum（C.cyminum）,Lantana camma（L.camara）,Nelumbo nucifera （N.nucifera） Phyllanlhus amarus（P.amarus）.Piper nigrum（P.nigrum） and Trachyspermum ammi（T.ammi） against Anopheles stephensi（An.stephensi） and Culex quinquefasciatus（Cx. quinquefasciatus）.Methods:The larvicidal activity of medicinal plant extracts were tested against earl) fourth-instar larvae of malaria and filariasis vectors.The mortality was observed 24 h and 48 h after treatment,data were subjected to probit analysis to determine the lethal concentrations(LC50 and LC90) to kill 50 and 90 per cent of the treated larvae of the tested species. The repellent efficacy was determined against two mosquito species at five concentrations（31.25. 62.50.125.00.250.00,and 500.00 ppm） under the laboratory conditions.Results:All plant extracts showed moderate effects after 24 h and 48 h of exposure;however,the highest activity was observed after 24 h in the leaf methanol extract ol N.nucifera.seed ethyl acetate and methanol extract of P.nigrum against the larvae of An.Stephensi(LC50 = 34.76.24.54 and 30.20 ppm) and against Cx.quinquefasciatus(LC50= 37.49.43.94 and 57.39 ppm),respectively.The toxic effect of leaf methanol extract of C.siamea,seed methanol extract of C.cyminum,leaf ethyl acetate extract of N.nucifera.leaf ethyl acetate and methanol extract of P.amarus and seed methanol extract of T.ammi were showed 100%mortality against An.stephensi and Cx.quinquefasciatus alter 48 h exposer.The maximum repellent activity was observed at 500 ppm in methanol extracts of N. nucifera.ethyl acetate and methanol extract of P.nigrum and methanol extract of T.ammi and the mean complete protection time ranged from 30 to 150 min with the different extracts tested. Conclusions:These results suggest that the leaf and seed extracts of C.siamea.N.nucifera.P. amarus.P.nigrum and T.ammi have the potential to be used as an ideal ecofriendly approach for the control of the An.stephensi and Cx.quinquefasciatus.

Sperm immobilization activity of Allium sativum L. and other plant extracts

<abstract>Aim: To identify possible spermicidal agents through screening a number of edible medicinal plants with antimicrobial activity. Methods: Initial screening was made on the basis of ram cauda epididymal sperm immobilization immediately after addition of extracts. The most potent extract was selected and was evaluated on both ram and human spermatozoa. To unravel its mode of action several sperm functional tests were carried out, namely viability of cells, hypo-osmotic swelling test for membrane integrity and assays of membrane-bound enzyme 5'-nucleotidase and acrosomal marker enzyme acrosin. Results: The crude aqueous extract of the bulb of Allium sativum L. showed the most promising results by instant immobilization of the ram epididymal sperm at 0.25 g/mL and human ejaculated sperm at 0.5 g/mL. Sperm immobilizing effects were irreversible and the factor of the extract responsible for immobilization was thermostable up to 90 癈. On boiling at 100 癈 for 10 minutes, this activity was markedly reduced. Moreover, this extract was able to cause aggregation of ram sperms into small clusters after 30 minutes of incubation at 37 癈. However this property was not found in human spermatozoa. More than 50 % reduction in sperm viability and hypo-osmotic swelling occurred in treated sperm as compared with the controls, indicating the possibility of plasma membrane disintegration which was further supported by the significant reduction in the activity of membrane bound 5'-nucleotidase and acrosomal acrosin. Conclusion: The crude aqueous extract of A. sativum bulb possesses spermicidal activity in vitro.

Synergistic effects of plant extracts and antibiotics on Staphylococcus aureus strains isolated from clinical specimens

Objective:This study has been done to evaluate the interaction between water extracts of Psidium guajava, Rosmarinus officinalis,Salvia fruticosa,Majorana syriaca,Ocimum basilucum,Syzygium aromaticum,Laurus nobilis,and Rosa damascena alone and then synergy testing of these extracts with known antimicrobial agents including oxytetracycline HCl,gentamicin sulfate,penicillin G,cephalexin and enrofloxacin.This study was conducted against five S.aureus isolates;one is Methicillin -resistant Staphylococcus aureus(MRSA) and 4 Methicillin - sensitive Staphylococcus aureus(MSSA).Methods:Evaluation of the interaction between plant extracts and different antimicrobial agents has been done using well - diffusion and microdilution methods. Results:The results of the conducted experiments using well - diffusion method demonstrate that these plants showed in vitro interactions between antimicrobial agents and plant extracts were additive,while using microdilution method showed synergistic effects with significant reduction in the MICs of the test antibiotics against these strains of S.aureus.This change in MIC was noticed in all plant extracts against test antibiotics including these plants showed weak antibacterial activity by well diffusion method.Synergism effect was occurred in both sensitive and resistant strains but the magnitude of minimum fold reduction of inhibitory concentration in resistant strains especially MRSA strain was higher than the sensitive strains.Coclusion:This study probably suggests the possibility of concurrent use of these antimicrobial drugs and plant extracts in combination in treating infections caused by S.aureus strains or at least the concomitant administration may not impair the antimicrobial activity of these antibiotics.

The Control Efficiency of Plant Alcohol Extracts on the Laboratory Populations of Myzus persicae(Sulzer)and Lipaphis erysimi (Kaltenbach)

The effects of semiochemicals extracted from 63 species of plants, on peach aphid (Myzus per-sicae) and mustard aphid (Lipaphis erysimi), were studied in laboratory. The deterrent rate, reproduction deterrent index and the interferential index of population control (IIPC) was used to evaluate the efficiency of semiochemicals on population control of the two target aphids. The results showed that the extracts of 34 species of common plants have noticeable effect on both aphid populations, especially, Xanthium sibiricum Petr. Et Widd. and Syngonium podophyllum Schott. These plant extracts could be used to construct the plant pro-tectant to protect crops.

Dietary plant extracts modulate gene expression profiles in alveolar macrophages of pigs experimentally infected with porcine reproductive and respiratory syndrome virus

Background: Our previous study showed that 3 plant extracts enhanced the immune responses and growth efficiency of weaned pigs infected with porcine reproductive and respiratory syndrome virus(PRRSV), which is one of the most economically important disease in swine industry. However, each plant extract differently effected on growth efficiency and immune responses. Therefore, the objective of this study was conducted to characterize the effects and investigate the potential underlying mechanisms of 3 plant extracts on gene expression of alveolar macrophages in weaned pigs experimentally infected with PRRSV.Results: PRRSV infection altered(P < 0.05) the expression of 1,352 genes in pigs fed the control(CON;755 up, 597 down). Compared with the infected CON, feeding capsicum(CAP), garlic botanical(GAR), or turmeric oleoresin(TUR) altered the expression of 46 genes(24 up, 22 down), 134 genes(59 up, 75 down), or 98 genes(55 up, 43 down) in alveolar macrophages of PRRSV-infected pigs, respectively. PRRSV infection up-regulated(P < 0.05) the expression of genes related to cell apoptosis, immune system process, and response to stimulus, but downregulated(P < 0.05) the expression of genes involved in signaling transduction and innate immune response.Compared with the infected CON, feeding TUR or GAR reduced(P < 0.05) the expression of genes associated with antigen processing and presentation, feeding CAP up-regulated(P < 0.05) the expression of genes involved in antigen processing and presentation. Supplementation of CAP, GAR, or TUR also enhanced(P < 0.05) the expression of several genes related to amino acid metabolism, steroid hormone synthesis, or RNA degradation, respectively.Conclusions: The results suggest that 3 plant extracts differently regulated the expression of genes in alveolar macrophages of PRRSV-infected pigs, especially altering genes involved in immunity.

Bioactivity of Four Plant Extracts on Coleopterous Pests of Stored Cereals and Grain Legumes in Nigeria

The efficacy of ethanol extracts from four plants, Dennettia tripetala Baker, Eugenia aromatica Baillon, Piper guineense Thonn et Schum and Anchomanes difformis P. Beauv. as bioinsecticides for control of adult Sitophilus zeamais Motschulsky, Tribolium castaneum Herbst, Callosobruchus maculatus Fabricius, Oryzaephilus mercator Fauvel and Lasioderma serricorne Fabricius were determined at two concentrations (0.5% and 2.0%) in the laboratory. All extracts were toxic to beetles with E. aromatica being the most potent of four plant materials tested and had the least LT 50 value. This was followed by A. difformis extract. At 2.0% v/w extract concentration, percentage grain damage by insects in treated grains stored for 90 days was nil. Grains protected with A. difformis had the least percentage seedgerminationof62.50%whilethoseprotectedwithP.guineensehadthehighestpercentagegermination(74.58%)at2.0% extract concentration. The mean percentage germination in the control was 72.72%. Treatment of grains with plant extracts had no significant (P>0.05) effect on its water absorption capacity.

Background correction in near-infrared spectra of plant extracts by orthogonal signal correction

In near-infrared (NIR) analysis of plant extracts, excessive background often exists in near-infrared spectra. The detection of active constituents is difficult because of excessive background, and correction of this problem remains difficult. In this work, the orthogonal signal correction (OSC) method was used to correct excessive background. The method was also compared with several classical background correction methods, such as offset correction, multiplicative scatter correction (MSC), standard normal variate (SNV) transformation, de-trending (DT), first derivative, second derivative and wavelet methods. A simulated dataset and a real NIR spectral dataset were used to test the efficiency of different background correction methods. The results showed that OSC is the only effective method for correcting excessive background.

Insecticidal Effect of Three Different Plant Extracts on Potato Tuber Moth[Phthorimaea operculella Zeller(Lep.:Gelechiidae)]

Potato tuber moth[Phthorimae operculella Zeller(Lep.:Gelechiidae)]is the most important insect causing damage of potatoes.It also causes significant damage to tomato and eggplant.The application of plant extracts to control insects is an effective alternative.In this study,the efficacy of extracts from Leptospermum petersonii Bailey(Myrtaceae),Achillea wilhelmsii C.Koch(Asteraceae)and Tanacetum parthenium L.(Asteraceae)on potato tuber moth using two different methods was investigated.Bioassays were used to determine the effect of varying concentrations(for L.petersonii 0.05%,0.1%,0.3%and 0.4%,for A.wilhelmsii and T.parthenium 1%,3%,6%and 12%)of extracts.Experiments were carried out using potato tuber of Solanum tuberosum L.Fourth instar larva of about were used in tuber dipping and larvae dipping methods.In tuber dipping method,the highest mortality(100%)occurred at concentration of 0.4%while the smallest mortality was at 0.05%the extracts of L.petersonii.It was determined that the extract of A.wilhelmsii and T.parthenium had the highest mortality at the highest concentration 85%and 90%respectively.In larva dipping method,the extracts of L.petersonii.A.wilhelmsii and T.parthenium showed the highest mortality at the highest concentrations 100%,82%and 87%respectively.The research was undertaken under laboratory conditions at the Plant Protection Central Research Institute.

Larvicidal efficacy of plant extracts and isolated compounds from Annonaceae and Piperaceae against Aedes aegypti and Aedes albopictus

The Aedes(Ae.)aegypti and Ae.albopictus mosquitoes are vectors of epidemiologically relevant arboviruses in the public health context,such as the dengue,Zika and chikungunya viruses.Among the alternatives to synthetic insecticides for the control of these vectors,the use of natural plant products deserves attention.This review summarizes findings on the larvicidal potential of plant extracts on Ae.aegypti and Ae.albopictus,as well as the potential of isolated compounds from plants of the Annonaceae and Piperaceae families against these vectors.Descriptors related to larvicidal activity of plant extracts and isolated compounds in Aedes spp.in the Web of Science database were used,for plant extracts considering publications between 2000 and 2019.A total of 859 articles were analyzed for plant extracts and estimates of lethal concentration values(LC50 and LC90).In the end,95 articles that presented the larvicidal potential of 150 plant species from 52 families were analyzed.The two families most studied for this activity were Fabaceae and Asterace Aedes.The plant families with the best LC50 values against mosquitoes were Piperaceae and Annonaceae.Larvicidal activity of 50 acetogenins has already been identified on Ae.aegypti,and 29 of them presented LC50 below 10μg/mL,as well as the larvicidal activity of 8 compounds isolated from Piperaceae.Therefore,plants of these two families are promising for the development of commercial botanical larvicides in the form of extracts and isolated substances,as well as the production via organic synthesis of the most active compounds.

Evaluation of the Safety and Efficacy of Extracts from the Leaves of Five Plants Used for the Treatment of Arterial Hypertension in Benin

Cardiovascular diseases (CVD) are nowadays real health problems in the world. High blood pressure is one of the most important risk factors for CVD and is affecting more and more people in Benin. The objective of our work is to evaluate the safety and the efficacy of the leaves of five plants used for the treatment of hypertension in Benin. Acute toxicity was evaluated on wistar rats which orally administered a single dose of 2000 mg/kg of body weight of hydro-ethanolic extract of the leaves of Phyllanthus amarus Schumach. & Thonn., Persea americana MILL., Ipomoaea fistulosa Mart. ex Choisy., Heliotropium indicum L., Schrankia leptocarpa DC., and were monitored over a period of 14 days. Subacute toxicity was evaluated on rats which received a daily dose of 200 mg/kg of body weight of the plant leaf extract over a period of 28 days. Plant efficacy was assessed by measuring potassium in plant leaves. Administration of the single dose of the extract did not cause any deaths in rats;the weight of the rats varied depending on the extracts administered. Concerning the subacute treatment, the levels of aspartate amino transaminases (AST) and Alanine amino transaminases (AST) did not vary significantly after the 28 days of treatment with the different extracts. On the other hand, a significant increase in serum creatinine was observed in rats treated with extracts of Phyllanthus amarus. The leaves of Heliotropium indicum, Ipomoaea fistulosa and Phyllanthus amarus contain the highest levels of potassium. Among the five plants studied, only the leaves of Phyllanthus amarus seem to induce renal toxicity. Extracts from the leaves of Heliotropium indicum, Ipomoaea fistulosa might be the most effective in inducing hypotensive activity and do not show toxicity.

Inventory and Management of Fungi Associated with Banana Plant through the Use of Allium ampeloprasum and Cymbopogon citratus Extracts

Despite the nutritional, economic and medicinal values of banana plant, independent of the region and production system is confronted with some diseases such as the fungi disease. These fungal diseases are responsible for the low yields. The objective of this study was to improve the sanitary state of banana plant. To achieve this objective, fungi associated with banana leaves were isolated on Potato Dextrose Agar (PDA) culture medium and their identification was done on the basis of morphological and microscopic characteristics using reference documents. Antifungal activity of Allium ampeloprasum and Cymbopogon citratus extracts were evaluated in vitro on agar medium on the development of Pseudocercospora fijiensis, P. musicola and Pestalopsis sp. The results showed that banana plant harbours a diversity of fungal species, the most frequent being P. fijiensis (51.58%), Pestalopsis sp. (15.47%) and P. musicola (12.03%). Aqueous extracts of C. citratus at the concentration of 15 mg/ml, inhibited 100% of the radial growth of P. fijiensis and Pestalopsis sp with a fungitoxic activity. Similarly, ethanolic extract A. ampeloprasum inhibited at 100% the radial growth of Pestalopsis sp. This antifungal activity was fungistatic. These results suggest that the aqueous and ethanol extracts of the tested plants could be used as alternatives to chemical products in the fight against banana diseases especially Sigatoka. Hence further studies need to be undertaken to isolate the active compounds from these extracts with fungicidal potential.

Phytochemical Determination and Antibacterial Activity of Punica granatum Peel Extracts against Plant Pathogenic Bacteria

Plant pathogenic bacteria are recognized to be harmful microbes able to decrease the quantity and quality of crop production in the world. Punica granatum peel was screened for its potential use as biological control agent for plant pathogenic bacteria. P. granatum peel was successfully extract using n-hexane, methanol and ethyl acetate by maceration. The highest yield obtained by ethyl acetate showed that ethyl acetate extracted more compounds that readily soluble to methanol and n-hexane. For in-vitro antibacterial activity, three different species of plant pathogenic bacteria were used namely Erwinia carotovorum subsp. Carotovorum, Ralstonia solanacearum, and Xanthomonas gardneri. For all crude extracts, four different concentrations 25, 50, 100 and 200 mg/ml were used in cup-plate agar diffusion method. Streptomycin sulfate at concentration 30 μg/ml was used as positive control while each respective solvent used for peel extraction was used as negative control. The results obtained from in vitro studies showed only ethyl acetate extract possessed antibacterial activity tested on the plant pathogenic bacteria. Methanol and n-hexane did not show any antibacterial activity against plant pathogenic bacteria selected where no inhibition zones were recorded. R. solanacearum recorded the highest diameter of inhibition zones for all range of concentrations introduced followed by E. carotovorum subsp. Carotovorum and X. gardneri. For the minimum inhbitory concentration (MIC) and minimum bactericidal concentration (MBC), only the ethyl acetate extract was subjected to the assay as only ethyl acetate extract exhibited antibacterial activity. The minimum concentration of ethyl acetate extract that was able to inhibit plant pathogenic bacteria was recorded at a concentration of 3.12 mg/ml which inhibited R. solancearum and E. carotovorum subsp. Carotovorum, followed by X. gardneri at concentration 6.25 mg/ml. For the minimum bactericidal concentration (MBC), the results showed that at the concentration of 12.5 mg/ml, the extract was still capable of killing the pathogenic bacteria, R. solanacearum, and P. caratovora sub.sp. caratovora while for the bacteria X. gardneri, the concentration that was able to kill the bacteria was 25 mg/ml. The qualitative estimation of phytochemical constituents within P. granatum L. ethyl acetate peel extracts had revealed the presence of tannins, flavonoids, phenols alkaloid, Saponins, and terpenoids. This study has demonstrated that Ethyl Acetate peel extracts of P. granatum has significant antibacterial activity against pathogenic plant bacterial, and it could be of high agricultural value.

Lethal and Sublethal Effects of Leaves Extracts from Native and Exotic Plants in Southern Brazil against Spodoptera frugiperda （Lepidoptera： Noctuidae） Caterpillars

The caterpillar Spodopterafrugiperda is an important pest of several crops, due to the damage it causes and the difficulty of its control. The method of controlling these pests is through chemical insecticides, which cause adverse effects to the biotic and abiotic environment. The selection of new insecticides that meet the requirements of efficacy, safety, selectivity and those are economically viable, is highlighting the study of mechanisms of plant defense. The present study aimed to verify the insecticide effect of 27 plants in three different types of plants extracts： aqueous, decoction and polypeptide on S. frugiperda. Three plants were chosen for performing sublethal effects bioassays： two plants with the highest corrected mortality （E. pulcherrima and R. simsii） and the other plant （Maytenus ilicifolia （espinheira santa）） with corrected mortality similar to control. In preliminaries bioassays, 25 plants showed corrected mortality less than 50%, according to Abbott＇s formula. R. simsii （azalea） and E. pulcherrima （billed parrot） showed 51% and 68% of corrected mortality, respectively. Only R. simsii aqueous and the three extracts of E. pulcherrima differ significantly from control （P 〈 0.05）. The aqueous extracts and decoction of R. simsii and polypeptide extract of E. pulcherrima reduced the larval period of S. frugiperda, different from control （P 〈 0.05）. The polypeptide extract of R. simsii reduced the pupal period of the target insect. The extracts obtained by decoction, aqueous and polypeptide of E. pulcherrima extracts and decoction of polypeptides and R. simsii affected the fertility and fecundity of S. frugiperda. For the other parameters, there is no significant difference when compared with the control. The results of this study suggest that the extracts obtained by decoction, aqueous and polypeptide of E. pulcherrima and R. simsii can be used to control S. frugiperda. However, the successful search, product starting from extracts of plants depends on the availability of plant and the entire assembly around the detection of bioactive products, in addition to the active ingredients of the chemical synthesis and elucidation of the target site insecticide molecule.

Effects of Plant Extracts with Antioxidant Activities on Male Mule Ducks＇ Performance

Plant extracts with antioxidant activities have effect on male mule ducks performance, and livestock animals have a strong metabolism activity, due to their high production requirements. It can lead to oxidative stress disorders; deteriorate growth performance and even their health. The objective of this study was to assess the effect of a mixture of active ingredients of plant extracts, known for their antioxidant and anti-inflammatory properties, on performances of mule ducks, in rearing and force-feeding period. Then 3,200 day-old mule ducks （MMGxPKL） were separated in 2 groups （negative control and treatment = EL） ×4 replicates per group for the rearing period. Each group received the same feeding program. EL group was supplemented, until the force-feeding period, with a mixture of actives from plants incorporated at 0.5% in the complete feed. At 84 days, the live weight and the feed consumption were measured for each treatment. Blood samples were also taken to measure the activity of two antioxidant enzymes： SOD （superoxide dismutase） and GPx （glutathione peroxidase）. For force-feeding, the ducks were separated among 3 farmers during 12 days. At slaughter, individual measures of breast and liver were conducted. At 84 days, mean live weight for EL group was improved by 3.7% （p 〈 0.001）. Feed conversion ratio was also improved （4.50 versus 4.62）. At slaughter, breast weight was higher for EL group （p 〈 0.01）. A high variability in the results of the activities of antioxidant enzymes was obtained. A decrease in SOD activity in erythrocytes was observed for the EL group （p 〈 0.05）. The results showed that the actives assessed in this study, distributed to ducks during the rearing period, had a beneficial effect on growth performance over that period. The mechanisms of endogenous antioxidant system and inflammatory responses remain to be elucidated.

Inhibitory Effects of Some Plant Extracts on 5 Bacterial Strains

[Objective] This study was conducted to develop potential natural plant products for controlling walnut blight pathogen and other bacteria. [Method] Inhibitory effects of extracts obtained from 15 plants with 3 solvents on bacteria were investi- gated by disk diffusion method. [Results] Except the extracts from Magnolia grandi- flora and Typha orientalis, extracts of 13 plant leaves presented inhibitory effects on 5 bacteria strains to certain degrees. Among them, the effect of water extract of Aesculu schinensis on Bacillus sp. XHE8 was the strongest, with inhibition zone di- ameter reaching （31.3＋3.9） mm and the ratio to control above 5.0. Four of the 5 tested strains were sensitive to the extracts of Sambucus chinensis, and 3 of them were inhibited by Ophiopegon japonicas extracts and Reineckia camea extracts, with ratios of treatment to control large than 1.5 in all. Leaf extract of A. chinensis had significant anti-bacteria ability, and could be used as a potential plant source for bactericide. [Conclusion] The results laid a foundation for exploring active com- pounds and elucidating the mechanism in it.

Antibacterial activity of eight Iranian plant extracts against methicillin and cefixime restistant Staphylococcous aureus strains

Objective:To assess the antibacterial activity of eight Iranian plant extracts against Staphylococcus aureus(S.aureus) strains which were isolated from infected patients.Methods: The studied strains were isolated from urine,stool,blood and wound of infected patients and identified by biochemical tests.In further,the antibacterial activity of 8 ethanolic local plant extracts including Querqus brantii(Q.brantii),Ziziphus spina-christi(Z.spina-christi),Peganum harmala(P.harmala),Oliveira decumbens(O.decumbens),Galium tricornutum(G.tricornutum), Vitex pseudo negundo(Vi.pseudo negundo),Salvia officinalis(S.officinalis),Vaccaria pyramidata (V.pyramidata) were then evaluated using agar disc diffusion method.Results:A total of 9 isolates were isolated and identified as S.aureus.Antibacterial profile of the strains showed that the strains were resistant to methicillin and cefixime.The highest antibacterial activity against the studied strains were belong to Q.brantii,P.harmala,Z.spina-christi and O.decumbens vent extracts with 11-40 mm,15-28 mm,8-26 mm and 10-20 mm of diameters,respectively. Intermediate antibacterial activity was exhibited by G.tricornutum and Vi.pseudo negundo against some of the studied strains with 7-20 mm and 7-13 mm of diameters,respectively. Noteworthy,out of 9 studied strains;6 and 2 of them were resistant to the G.tricornutum and Vi. pseudo negundo extracts,respectively.The S.officinalis and Va.pyramidata,however,showed no antibacterial activity against the studied strains.Conclusions:The Q.brantii,P.harmala,Z. spina-christi and O.decumbens extracts were shown to possess strong antibacterial activity against methicillin and cefixime resistant S.aureus strains and can be considered as the promising natural antibiotics for treating the studied strains.

Effect of plant extracts on activity of some defense enzymes of apple fruit in interaction with Botrytis cinerea

The efficacy of seven plant extracts(neem,fennel,lavender,thyme,pennyroyal,salvia and asafetida) in controlling postharvest of apple(caused by Botrytis cinerea) was evaluated in vitro and in vivo.In vitro,all plant extracts treatments inhibited spore germination.Inhibitory rates of pore germination was 17.41 and 20.83% for neem extract treatment(methanolic and aqueous extracts,respectively) with significant difference compared to control(73.6 and 85.33%) for aqueous and methanol extracts.In the storage conditions,the application of aqueous extract of neem(at concentration of 25%) resulted in 89.11% reduction of disease severity compared with the untreated control.Results of enzymes activity showed the plant extracts can increase the activity of peroxidase,phenylalanine ammonia-lyase,β-1,3-glucanase and polyphenol oxidase in the presence of pathogens,in apple fruits.However,the results of this research revealed that application of neem extracts was more effective than the application of other plant extracts.According to this study,it could be concluded that plant extracts may be useful to control postharvest disease as a safe alternative option to chemical fungicides.

Anti-Insect Activity of the Methanol Extracts of Fern and Gymnosperm

With environmental and food safety issues becoming one of the greatest concerns of the public, active plant compounds play more and more important roles in pest controlling. Fern to their particular status in plant taxology and co-evolution are of great significance for application as new pesticides due with insects. In this study, methanol extracts were distilled from wild fern and gymnosperm of 54 species of 22 families collected from Shiwandashan Mountain in Guangxi Zhuang Autonomous Region of China. Insecticidal activities of the methanol extracts were assayed on both adult house fly （Musca domestica） and mosquito （Aedes albopictus）. Significant insecticidal activities were exhibited in the methanol extracts of five species, Cupressusfunebris （leaves and stems）, Cycas acuminatissima （roots）, Keteleeria fortunei （leaves and stems）, Onychium japonicum （whole plant）, and Pinus taiwanensis var. Darning shanensis （leaves and stems）. Applications of the extracts of these plants resulted in higher than 50% mortalities in 4th instar larvae of A. albopictus at 24 h after treatment. The methanol extracts from 13 species possessed insecticidal activities against the adult of M. domestica at 48 h after treatment with higher than 90% mortalities. The extensive screening results showed that these fern and gymnosperm were highly potential to be botanical insecticides. The findings provide a feasible and valuable basis for further investigation.