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Biology ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 3
Author(s):  
El-Said M. Elnabawy ◽  
Sabry Hassan ◽  
El-Kazafy A. Taha

This study was conducted to compare the repellent effect and contact toxicity of eight essential oils (EOs), including Syzygium aromaticum, Allium sativum, Eucalyptus camaldulensis, Lavandula officinalis, Simmondsia chinensis, Matricaria chamomilla, Citrus limon, and Prunus dulcis, against adults of Tribolium castaneum Herbst. Four concentrations (1, 5, 10, and 15% in acetone solvent) of each EO were tested. The 5, 10, and 15% concentrations of S. aromaticum EO had a high repellency effect against T. castaneum compared with A. sativum, E. camaldulensis, L. officinalis, S. chinensis, M. chamomilla, C. limon, and P. dulcis after 30 min of exposure. The repellency test of the S. aromaticum, E. camaldulensis, L. officinalis, M. chamomilla, C. limon, and P. dulcis EOs on T. castaneum has shown that the mortality percentages enhanced with the increase in the EOs concentration and also with the exposure time. The 15% concentration of P. dulcis and M. chamomilla EOs have a significant impact on the mortality rate of T. castaneum compared with S. aromaticum, A. sativum, E. camaldulensis, L. officinalis, and S. chinensis after the 24 h of contact test. Moreover, the 15% concentration of the C. limon EO caused a greater mortality percentage compared with S. aromaticum, A. sativum, E. camaldulensis, and L. officinalis. It could be concluded that using the S. aromaticum EO as a repellent oil and using P. dulcis, M. chamomilla, and C. limon for contact toxicity to treat the flour infested by T. castaneum can play an important role in protecting stored grains and their products.


2021 ◽  
Vol 14 (1) ◽  
pp. 104
Author(s):  
Sawsan S. Moawad ◽  
Ibrahim M. A. Ebadah

The Experiment was carried out to measure the effect of four natural plant oils (namely: Cinnamonium zeylanicum L., Syzygium aromatic L., Citrus aurantium amara, and Lavandula spica) on controlling the greater wax moth and their ability to persist. The methodology included collecting and rearing the greater wax moth under laboratory conditions to be able to isolate the target tested stages. The immature stages (eggs and larvae) of the experiment moth were exposed to fumes of tested oils (50 µl/500 ml) to calculate hatchability and mortality percentage. The results were clear that fumes of C. zeylanicum and S. aromatic were caused 100% unhatching eggs after zero time as the same recorded by comparable compound (paradix) and able to persist their effect at the closed and limited zone for 60 days. On another side, C. zeylanicum and S. aromat were affected on last larval instars and emerged adults. The accumulative effect was appeared in the case of treatment by C. zeylanicum which was caused sterility to emerged adults and reduced eggs deposition to zero. The data indicated that some natural product compounds could be used as an alternative way of control insect pests.


2021 ◽  
Vol 913 (1) ◽  
pp. 012016
Author(s):  
A Wulansari ◽  
A Purwito ◽  
D Sukma ◽  
TM Ermayanti

Abstract Taro genetic improvement through polyploidy induction is expected to be tolerant to abiotic stress. Several studies have shown that polyploidy plants have a higher adaptability to dry environments. In vitro selection technique for evaluation of plant tolerance to drought stress can be done by applying polyethylene glycol (PEG) as a selection agent. The aim of the research was to investigate the growth response of diploid and tetraploid taro shoot culture to drought stress using PEG. The experiment was conducted using a completely randomized design with two factors. The first factor was the concentration of PEG at 0, 5, 10, 15 and 20%. The second factor was Bentul taro clones which were 1 diploid clone and 2 tetraploid clones (clones 4.6.3 and 5.4.4). PEG was added to liquid MS medium containing 2 mg/l BAP. Observations of growth variables were carried out every week until the six weeks of culture. Fresh and dry weights, mortality percentage and proline content were determined at six weeks of culture. The results showed that the addition of PEG in liquid medium significantly affected the number of leaves, petiole length, number of roots, fresh and dry weights, as well as shoot mortality percentage. Differences in clones significantly affected the number of leaves, fresh and dry weights. The two factors tested (PEG and clones), gave an interaction on the number of leaves, fresh and dry weights. The proline content in all diploid and tetraploid clones showed an increase with increasing PEG concentration. The LC50 value in diploid clones was 9.82%, in tetraploid clones 4.6.3 and 5.4.4 were 14.14 and 15.45%, respectively. The results showed that PEG at 10% and 15% could be used for in vitro selection to drought stress both for diploid and tetraploid taro.


2021 ◽  
Vol 20 (2) ◽  
Author(s):  
Ana Windari ◽  
Mimatun Nasihah ◽  
Nur Lathifah Syakbanah

Dengue Hemorrhagic Fever (DHF) is an acute disease in the form of dengue virus infection which is spread through mosquito bites. The use of synthetic insecticides actually causes negative effects on the environment, so another alternative is needed, namely the use of bay leaf vegetable insecticides. The purpose of this study was to determine the effectiveness of bay leaf insecticide (Syzygium polyanthum) as an insecticide against the mortality of Aedes Aegypti mosquitoes with the liquid electric method. This study used a quasi-experimental (quasi-experimental) design with a completely randomized design (CRD) method where the experiment was conducted on 150 mosquitoes in 5 treatments and 3 replications. The results of the percentage of bay leaf solution (Syzgium polyanthum) which has the largest number of mosquito mortality at a concentration of 80 ml/200 ml of water with a mortality percentage of 60%. The result of probit LC50 analysis of bay leaf solution was 64,315 g/ml. The higher the concentration of the solution given, the greater the number of mosquito mortality. It is necessary to modify the right tools and methods to make a solution of bay leaf (Syzgium polyanthum) so that it is more effectively applied in the community.Keywords: bioinsecticide, bay leaf, liquid electric, mortality, Aedes aegypti


Redia ◽  
2021 ◽  
Vol 104 ◽  
pp. 147-154
Author(s):  
GIUSEPPE MAZZA ◽  
FRANCESCO BINAZZI ◽  
DANIELE MARRACCINI ◽  
LUCA BONCOMPAGNI ◽  
GIUSEPPINO SABBATINI PEVERIERI ◽  
...  

Ricania speculum is an alien insect feeding on several host plants belonging to several families, including important vegetables, crops, ornamental plants, wild plants as well as trees. For the first time, recently, Chrysoperla sp. and coccinellid beetles have been observed preying on this species in the field on Citrus sp. and Laurus nobilis plants. The main purposes of this work were to evaluate the possible predation capability of these groups of insects and determine their prey preference in laboratory trials. In the choice trials, R. speculum nymphs were paired in a confined space and exposed for 24h to single predators: Ch. carnea complex and to the coccinellids Cryptolaemus montrouzieri, Adalia bipunctata, Coccinella septempunctata, and Propylea quatuordecimpunctata. Specimens of Aphis rumicis, an aphid frequently found on her baceous plants, were used as a control prey. In the cage trials, a single Ch. carnea complex second-instar larva was placed into a jar containing a tomato plant with ten R. speculum nymphs. In the choice trials, a high mortality percentage of both preys was observed with the Ch. carnea complex, while in those with Coccinellids only high A. rumicis mortality was reported. In the cage trials, 13% mortality of R. speculm was recorded after 24h while after 72h and 168h prey mortalities reached 18% and 25%, respectively. The results of the study showed that larvae of the Ch. carnea complex could be potential predators of R. speculum, while coccinellids do not seem promising predators of this alien species.


2021 ◽  
Vol 39 (2) ◽  
pp. 168
Author(s):  
I Gusti Komang Oka Wirawan ◽  
Aholiab Aoetpah ◽  
Jois Moriani Jacob

Acacia nillotica and Desmanthus virgatus are two entopharmacologycal plants that thrives throughout the season in East Nusa Tenggara Province, other Provinces in Indonesia or tropical countries. Extraction of young leaves of Acacia nillotica (EDMAN) and Desmanthus virgatus (EDMDV) contains tannin compound. By pharmacodynamic viewpoint, this extraction has potency as an anthelmintic. Objective: to compare the in-vitro effectivity of young leaves extraction of the two plants as a vermicidal power to combat Haemonchus contortus. Materials: young leaves of Acacia nillotica and Desmanthus virgatus and Haemonchus contortus. Method: The study was grouped into four treatments: EDMAN, EDMDV, Positive control (Albendazole 0,055%) and negative control (aquades).  The concentration of the young leaves extracts are 2.5%, 3.5%, 4.5% out of 0.01 g/mL of extraction. Each treatment was applied to 6 female Haemonchus contortus with four replicates allowing immersion time for 1, 3, 5 or 7 hours. Variable measured and tested was mortality of the H. contortus. The vermicidal effectively was descriptively analysed. The results showed that mortality percentage (vermicidal) treatment of 2.5%, 3.5%, 4.5% EDMAN for 7-hour immersion was 16.7%, 45.8%, 12.5%, respectively. That values for EDMDV for similar concentrations and immersion time was 50%, 33.3%, 12.5%, respectively. Conclusion: EDMDV has a more effective vermicidal power between the two etnopharmacological treatments at 2.5% concentration.


2021 ◽  
Vol 12 (2) ◽  
pp. 299
Author(s):  
Yustin Nur Khoiriyah ◽  
Nurminha Nurminha

<p>The <em>Aedes aegypti</em> mosquito can develop an immune system against the insecticide used. Control efforts with the use of insecticides are no longer effective if the target insects have become resistant. So there needs to be an effort to overcome the insect resistance that is targeted. Citronella grass is an herbal plant that can be used as an ingredient in vegetable pesticides. The leaves and stems are distilled to produce essential oil known as citronella oil. This research is about studying the effects of citronella oil against the resistance of the vector carrier for dengue fever, namely <em>Aedes aegypti. </em>The detection of citronella essential oil (<em>Cymbopogon nardus</em> L.) by Thin Layer Chromatography showed a reduction in UV<sub>254</sub> visualization (Rf 0,68). The resistance test showed that the mortality percentage of adult mosquitoes <em>Aedes aegypti</em> exposed to 0.03% alphacymethrin was 73,7% resistant criteria (&lt;90%). The mortality percentage of adult mosquitoes <em>Aedes aegypti</em> exposed to Alphacypermethrin (0,03%) and citronella oil was 2,5% each; 5%; 7,5% and 10% with treatment time 15 respectively, namely 18,7%, 50,7%, 70,7% and 82,7%; the treatment time of 30 minutes consecutively is 62,7%, 89,3%, 96% and 97,3% and the treatment time is 60 minutes respectively, namely 93,3%, 98,7%, 98,7% and 100%. There was an increase in the percentage of mosquito deaths exposed to the combination of alphacypermethrin and citronella oil, compared to those without citronella oil, this indicates that mosquitoes are more susceptible and resistance has decreased due to exposure to citronella oil. <strong></strong></p>


2021 ◽  
Author(s):  
Parveen Gill ◽  
Sudhakara Rao ◽  
Rajender Gupta ◽  
Dharambir Singh ◽  
Tejpal Dahiya ◽  
...  

Abstract Because of their high biomass in the soil, earthworms are used as bio-indicator species for assessing soil toxicity against pesticides. The regular observed sensitivity to relatively low pesticide concentrations exits in soils is a significant ecological observation. Insecticide residues harm the flora of beneficial invertebrates and harm the physiological functions of earthworms, resulting in death. They affect morphological parameters as well as internal organs, and eight different imidacloprid concentrations (0.050 µl/cm2, 0.100 µl/cm2, 0.150 µl/cm2, 0.200 µl/cm2, 0.250 µl/cm2, 0.300 µl/cm2, 0.350 µl/cm2, 0.400 µl/cm2) were prepared with water during the procedure. To establish the LC50 value, earthworms of Eisenia fetida were exposed to various concentrations of imidacloprid using the usual paper contact toxicity method, and their toxicity levels are established. The mortality percentage was estimated after 24 hours of imidacloprid exposure, and a dosage of 0.195 µl/cm2 resulted in 50% mortality of earthworms. When higher concentrations of imidacloprid were used, negative effects were observed. For ecotoxicological evaluations, the following morphological and behavioural changes were observed during the experiment: Preclittelar bulging, body constriction, blackening of the body, segment swelling, oozing of coelomic fluid, body constriction, cuticle rupture, and oozing of fluid from the body are all common side effects.


Author(s):  
M. Abhilash ◽  
T.R. Kannaki ◽  
E. Priyanka ◽  
Santosh Haunshi

Background: Fowl cholera is a highly fatal, contagious bacterial disease that incurs significant economic loss in commercial as well as back-yard poultry. Vaccination is the most effective way in controlling this disease. In this study, we prepared and evaluated the immunogenicity of iron- inactivated Pasteurella multocida A:1 vaccine and its protective efficacy against fowl cholera experimental infection in backyard chicken.Methods: Scaled up Pasteurella multocida A:1 culture with 5 X 108 CFU/ml equivalent to 2.5 mg of antigen per dose was used for preparation of experimental vaccines. Formalin inactivated and mixed with APS adjuvant (FIA), formalin inactivated-Freund adjuvant (FIF), Iron inactivated and adjuvanted with iron (III), Iron inactivated from iron supplemented media and adjuvanted with iron (ISII) and commercial oil emulsion vaccine (CV) were used in the study. A total of 120 Vanaraja birds (n=20/group) of 2 weeks age were immunized with these vaccine and booster were given at 3rd and 6th week with respective vaccine. Specific antibody titers were assessed by iELISA in the serum at weekly intervals. The birds were challenged (n=6 /group) with 5x104 CFU/ml of virulent isolate by intraperitoneal route and morbidity, mortality percentage were observed.Result: Protective antibody titers were induced by iron inactivated vaccine from 4th week of immunization and upon booster doses it induced significantly higher (P less than 0.05) antibody response. The iron inactivated experimental vaccine gave equivalent protection as that of commercial vaccine upon challenge infection.


2021 ◽  
Author(s):  
Sunil Soni ◽  
Samunder Singh ◽  
Rajbir Garg

Rumex spp. is most dominating broad-leaf weed of wheat crop. Complaints of poor efficacy of different herbicides against Rumex spp. have reported recently from different locations of Haryana state. Therefore, the present study was carried out under completely randomised design, replicated thrice, using three different herbicides namely carfentrazone + metsulfuron, sulfosulfuron + metsulfuron and halauxifen as treatments applied with three doses against four populations of Rumex spp. Plant height, chlorophyll fluorescence, electrical conductivity, mortality percentage and dry weight were recorded as observations. Results indicated that most of the Rumex biotypes were found resistant against sulfosulfuron + metsulfuron application. Majority of biotypes were moderately controlled by the application of halauxifen. Carfentrazone + metsulfuron effectively controlled the Rumex spp. and provided 70-90 % control to all biotypes at double of the recommended dose. As per results of this study, carfentrazone + metsulfuron can be recommended for control of Rumex spp. in wheat.


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