scholarly journals Evaluation of the Potential of Fungal Biopesticides for the Biological Control of the Seed Bug, Elasmolomus pallens (Dallas) (Hemiptera: Rhyparochromidae)

Insects ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 277
Author(s):  
Fredrick Fidelis Umaru ◽  
Khanom Simarani

Elasmolomus pallens is a post-harvest insect pest of groundnuts which causes severe yield loss to farmers, particularly in Africa and Asia. Resistance to synthetic chemicals has been on the rise among insects and is a constraint on insecticides regulations. In view of the drive for alternative approaches to synthetic insecticides, this study evaluated the potential of biopesticides based on entomopathogenic fungi against E. pallens under laboratory conditions. Fungal isolates from the bug cadaver including Fusarium proliferatum F1, Aspergillus tamarii F2, A. flavus F3, Trichoderma atroviride F4, A. niger F4, and Metarhizium anisopliae (Meschn.) Sorokin, originating from the cadaver of Zonocerus variegatus were screened for virulence against the bug. Adult bugs were dipped briefly in conidial concentration 1 × 108 conidial mL−1 and observed at 25 ± 2 °C, 80 ± 10 RH and 14: 10 L:D for 10 days. The fungal isolates caused mortality ranging from 48 to 100% based on their potential to infect and kill the bug. Five conidial concentrations (1 × 104 to 1 × 108 conidia mL−1) were evaluated against adult bugs in the multiple-dose virulence bioassay. Lethal concentrations (LC50 and LC90) values of 6.75 × 106 and 4.42 × 109 conidia mL−1 were obtained for A. flavus F3 while M. anisopliae had 8.0 × 106 and 6.14 × 108 conidia mL−1 respectively. Lethal time (LT50 and LT90) values were 3.3 and 6.2 days for A. flavus F3 compared to 3.6 and 5.6 days for M. anisopliae, respectively. Thus, A. flavus F3 showed potential against E. pallens; and can be considered as an ideal isolate for incorporation into formulations for field applications.

Agrikultura ◽  
2016 ◽  
Vol 27 (1) ◽  
Author(s):  
Nono Carsono ◽  
Gigih Ibnu Prayoga ◽  
Neni Rostini ◽  
Danar Dono

ABSTRACTMolecular Marker-based Selection on F2 Progeny for Development of Promising Rice Lines Resistant to Brown PlanthopperBrown planthopper (BPH) is the major insect pest of rice and accounts for significant yield loss. This experiment was aimed to develop BC1F1 and F3 brown planthopper resistant rice lines. Selection on the basis of SSR markers can be done by using two polymorphic SSR markers, i.e., RM586 dan RM8213, which screened from eight SSR markers for BPH resistant. Sixty-three F2 genotypes from IP-1 (derived from IR-64 x PTB-33) population and twenty F2 genotypes from PP-11 (derived from Pandan Wangi x PTB-33) population were selected and will be used for further research by selfed and backcrossed to recipient parents. Chi-squares test for segregation of DNA bands in F2 generation showed that RM8213 fitted with 1:2:1 Mendelian ratio for controlling photosynthetic rates and trichomes length in IP-1 population. This information could be used in programs to develop a durable brown planthopper resistant rice cultivar.Keywords: BPH, F2 population, Moleculer marker, SSRABSTRAKWereng coklat merupakan salah satu hama utama pada tanaman padi yang mampu menurunkan produksi padi secara nyata. Penelitian ini bertujuan untuk memperoleh galur-galur padi F2 yang memiliki marka-marka yang berasosisasi dengan ketahanannya terhadap wereng coklat. Seleksi pada galur padi F2 hasil persilangan telah dilakukan melalui teknik marka molekuler Simple Sequence Repeat (SSR) menggunakan dua marka SSR yang menunjukkan polimorphisme yaitu RM586 dan RM8213 dari delapan marka yang diskrining. Sebanyak 63 genotip dari populasi IP-1 (hasil persilangan IR-64 x PTB-33) dan 20 genotip dari populasi PP-11 (hasil persilangan Pandan Wangi x PTB-33) untuk disilangkan sendiri maupun disilang balik dengan tetua recipient. Selain itu, hasil analisis Chi-Kuadrat untuk segregasi pita DNA menunjukkan bahwa primer RM8213 memiliki rasio 1:2:1 (dominasi tidak sempurna) dalam mengontrol karakter laju fotosintesis dan panjang trikoma terhadap wereng coklat pada populasi IP-1. Informasi yang diperoleh dari penelitian ini nantinya dapat digunakan untuk program perakitan kultivar padi tahan wereng coklat yang durable.Kata Kunci: Marka molekuler, Populasi F2, SSR, Wereng coklat


2021 ◽  
Vol 25 (1) ◽  
pp. 1-22
Author(s):  
MP Ali ◽  
B Nessa ◽  
MT Khatun ◽  
MU Salam ◽  
MS Kabir

The damage caused by insect pest is the continual factor for the reduction of rice production. To date, 232 rice insect pest species are identified in Bangladesh and more than 100 species of insects are considered pests in rice production systems globally, but only about 20 - 33 species can cause significant economic loss. The major goal of this study is to explore all the possible ways of developed and proposed technologies for rice insect pests management and minimize economic losses. Insect pests cause 20% average yield loss in Asia where more than 90% of the world's rice is produced. In Bangladesh, outbreak of several insects such as rice hispa, leafroller, gallmidge, stem borers and brown planthopper (BPH) occurs as severe forms. Based on previous reports, yield loss can reach upto 62% in an outbreak situation due to hispa infestation. However, BPH can cause 44% yield loss in severe infestested field. To overcome the outbreaks in odd years and to keep the loss upto 5%, it is necessary to take some preventive measures such as planting of resistant or tolerant variety, stop insecticide spraying at early establishment of rice, establish early warning and forecasting system, avoid cultivation of susceptible variety and following crop rotation. Subsequent quick management options such as insecticidal treatment for specific insect pest should also be broadcasted through variety of information systems. Advanced genomic tool can be used to develop genetically modified insect and plants for sustainable pest management. In addition, to stipulate farmers not use insecticides at early crop stgae and minimize general annualized loss, some interventions including training rice farmers, regular field monitoring, digitalization in correct insect pests identification and their management (example; BRRI rice doctor mobile app), and demonstration in farmers field. Each technology itself solely or combination of two or more or all the packages can combat the insect pests, save natural enemies, harvest expected yield and contribute to safe food production in Bangladesh. Bangladesh Rice J. 25 (1) : 1-22, 2021


2019 ◽  
Vol 56 (04) ◽  
pp. 1037-1044
Author(s):  
Saif-Ur Rehman

Entomopathogenic fungi (EPF) are suggested as a new class of alternates followed by Synthetic chemical control of the insect pests .Virulence of seven EPF isolates, four strains of Metarhizium {(Qin-08, Qin-13, Qin-18 and ME-38 (LT-178)}, two of Isaria {ME-33 (ILT-01), Yulin-5 (IYL-01)} and one of Beauveria bassiana (Qin-21) were assessed against the adults of Sitophilus oryzae under laboratory conditions, firstly at single conidial concentration (1x108 ml-1 ) by immersion and the food mix methods. Qin-21, ME-33 and Qin-18 caused significantly highest mortality of S.oryzae at immersion methods (100, 100 and 98%), followed by food mix method to 100, 84.16 and 91.66% respectively. Yulin-5 was the least effective, showing significantly the lowest mortality at food mixed (32.49%) and immersion methods (40.20%) respectively. Hence, the immersion method was found to be most effective, resulting the higher mortality rate of S. oryzae in comparison to food mix method, in all tested fungal isolates. Secondly, we screened out the most effective isolates for multiple dose comparison i.e., 1x104 to 1x107 conidia ml-1 by immersion method only. The isolate ME-33 resulted in 100% mortality of the pest at higher conidial dose as compared to Qin-21 and Qin-18 which showing 80 and 64.64% mortality respectively. The LT50 was observed to be 3.63, 4.17 and 8.58 days in ME-33, Qin-21 and Qin-18, respectively at the highest conidial concentration (1x107ml-1 ). ME-33 isolate with the highest mortality and lowest LT50 at conidial concentration 1x107 ml-1 proved to be most effective for the control of S. oryzae. So these fungal islotes could be a better alternative for the management of S. oryzae


2017 ◽  
Vol 51 (04) ◽  
Author(s):  
Abdul Sadat ◽  
Kaushik Chakraborty

A survey on jute farmers’ knowledge, perceptions and practices (KPP) in pest management strategy was conducted during jute cultivation season of 2015 in the upper Gangetic plains of Uttar Dinajpur District, West Bengal, India. Detection and control of insect pests was largely based on damage symptoms of host plant. Damage caused by jute semilooper (Anomis sabulifera) was often mistakenly attributed to other leaf feeding caterpillars. Nearly all of the farmers applied insecticides (99%) without target specific use with an average 1.5 per season which may increase up to two to three spray per week. Pyrethroids were mostly accepted insecticide (67%), followed by organophosphates (33%) without knowing its toxic effect on environment. Farmers’ estimated yield loss due to insect pests was significantly correlated to estimated pest control cost. Due to pesticide sellers’ recommendations, farmer’s insecticidal ‘spray load’ significantly increased in every year, whereas the adopted number of insecticidal increased with advice following the guidance of extension staff and advertisement. Expenditure for pesticides was in concurrent with that of fertilizers. Only 10% of participating farmers knew about natural enemies, all of which were predators. Investigation is needed to evaluate whether significant savings can be obtained given a more judicious use of pesticides.


2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Velavan Viswakethu ◽  
Padmanaban Balakrishanan ◽  
Loganathan Murugan ◽  
Baskar Narayana swamy ◽  
Uma Subbaraya

Abstract Background Banana fruit scarring beetle (BFSB), Basilepta subcostata (Jac.) (Chrysomelidae:Coleoptera), is an important insect pest feeds on leaf and fingers, which affects the cosmetic value of the fruit. The pest is distributed in Assam, Bihar, West Bengal, Chhattisgarh, and North-eastern Hill regions of India. Results The pest is currently managed by foliar spray with insecticides. In order to identify eco-friendly control of the pest, attempts were made to isolate microbial agent and evaluate their potential to control the pest. A total of 27 entomopathogenic fugal isolates were obtained from Odoiporus longicollis (Oliver), Cosmopolites sordidus (Germar), Basilepta subcostata (Jac), and other insect Galleria mellonella (Fabr). Based on colony morphology, the collected fungal isolates were identified as Metarhizium spp. (17) and Beauveria spp. (10). Through ITS sequencing, the fungal isolates were further characterized at species level as B. bassiana (8), B. brongniartii (2), M. anisopliae (8), M. robertsii (6), M. guizhouense (2), and M. pinghaense (1). Their sequences were submitted in GenBank and obtained accession numbers. Among 27 isolates tested against B. subcostata under laboratory conditions, 3 isolates (M. anisopliae NRCBEPF-36, M. pinghaense NRCBEPF-7 and B. brongniartii NRCBEPF-27) recorded 100% beetle mortality, followed by 11 isolates with 95–99% and 13 isolates with 88–93% within 8 days of treatment. Conclusion This study highlights the two native North East India isolates B. brongniartii NRCBEPF-27 (MT151781) and M. anisopliae NRCBEPF-36 (MT140308) showed the significance to use as potential biocontrol agents against banana fruit scarring beetle B. subcostata. Further experiments under field conditions are required to evaluate their biological control efficacy against the pest.


2021 ◽  
Vol 37 (2) ◽  
pp. 103-112
Author(s):  
N.G Iyany ◽  
A.E Ataga

Jatropha curcas is a plant of great economic importance that experiences high incidence of fungal attack. Misidentification of the fungal species is bound to occur with the use of traditional cultural methods where organisms are identified morphologically and/or microscopically. This study was carried out to isolate and identify the fungi associated with Jatropha curcas (L.) using both traditional/ cultural techniques and molecular methods. The fungi were isolated from diseased leaves and stems of J. curcas using both Standard Blotter and Potato Dextrose Agar (PDA) methods. DNA was extracted from the fungal isolates using Zymo Fungal/Bacteria DNA MiniPrep Kit. Amplification of the Internal Transcribed Spacer (ITS) regions of the fungal isolates was carried out using fungi universal primer pairs for ITS4 and ITS5. The amplicons were sequenced and the isolates were identified as Penicillium brevicompactum, Aspergillus sp., Botryosphaeria rhodina, Aspergillus nomius, Aspergillus tamarii, Rhizopus oryzae, Penicillium citrinum and Fusarium solani. Phylogenetic analysis was carried out to know the relationship between the isolates and other closely-related species in GenBank. Jatropha curcas is colonized by many fungal species some of which may be pathogenic to the plant, and molecular techniques pose the best alternative for accurate identification of these organisms. Keywords: Jatropha curcas, fungi, polymerase chain reaction, phylogeny, sequencing


2018 ◽  
Vol 34 (3) ◽  
pp. 127
Author(s):  
Horas Sihotang ◽  
Sitti Umniyati

Purpose:  The purpose of this study was to confirm the resistance status and resistance ratio (RR) of  Ae. aegypti larvae to temephos as well as to determine the effectiveness of a liquid solution of Bti H-14 and the essential oil of ginger (Zingiber officinale roxb) against Ae. aegypti larvae from Deli Serdang, North Sumatra.Method: A randomized post-test only control group was con- ducted using 3rd instar larvae of Ae. aegypti as the subjects of this study. Larval mortality was recorded after 24 hours of exposure with diagnostic dose of temephos (0.02ppm) to determine the resistance status. Probit analysis was conducted to determine median lethal time (LT50) and the RR. The concetration of Bti toxicity test was 0.01, 0.013, 0.017, 0.02, 0.03 and 0.04 mL/L and the concentration of toxicity essential oil of ginger test was 66.6, 99.9, 133.2, 166.5, 199.8 and 266.4 ppm.Results: Ae. aegypti larvae were resistant to temephos (0.02ppm) with RR 1.9 < 5. The value of LC50 and LC90 of Bti were 0.014; 0.024 mL/L respectively. The value of LC50 and LC90 of essential oil of ginger solution were 65.6ppm and 129.1ppm respectively.Conclusion: Larvae are resistant to temephos with low resistance criteria. Bti and essential oil of ginger are toxic to Ae. aegypti larvae.


2020 ◽  
Vol 5 (1) ◽  
pp. 06-09
Author(s):  
Poonam Belbase ◽  
Archana Aryal ◽  
Ashim Aryal

The research on varietal screening of rice against leaf folder, caseworm and grasshopper damage was conducted during 2019 in Rampur, Chitwan to study the host plant resistant of different varieties of rice under field condition. The experiment was laid out in RCBD with three replications and seven treatments namely i) Makawanpur -1 ii) Mansuli iii) Radha-4 iv) Ramdhan v) Sabitri vi) Sama Mansuli sub-1 and vii) sukkha-3. The experiment revealed that lowest population of leaf folder, caseworm and grasshopper was recorded in variety Radha-4 followed by Ramdhan. The experiment showed the yield loss was significantly lower in Radha-4 followed by Sabitri and Ramdhan due to leaf folder, caseworm and grasshopper. So Radha-4 and sabitri would be good option in rice production for reducing insect pest damage.


Author(s):  
Deepak Kumar ◽  
M.K. Singh ◽  
Hemant Kumar Singh ◽  
K.N. Singh

2021 ◽  
Author(s):  
Alizèta Sawadogo ◽  
Issaka Zida ◽  
Marc Kenis ◽  
Souleymane Nacro

Abstract In Burkina Faso, the leaf beetle Aphthona whitfieldi is the main insect pest of the biofuel plant Jatropha curcas. The beetle affects plant growth and seed yield, but the impact on yield has never been properly quantified. This study was conducted on-station and on-farm in the district of Léo, southern Burkina Faso, in 2015. It aimed at evaluating the yield losses that A. whitfieldi inflicts to J. curcas. The first experiment used 25 caged trees in their first year of fruit production, on which various amounts of beetles were released. When 200 beetles were released, the defoliation level reached 55% and caused 61% of yield loss. Releases of 400 or more beetles caused a defoliation level of at least 74% and seed losses of 98%. On-farm observations were made on attack levels and seed yields in three different types of plantations, i.e. pure plantations, plantations intercropped with food crops and hedges. These observations showed that defoliation levels over 50% were common in the three types of plantations, resulting in very low yields. This study shows the importance of beetle damage in the cultivation of J. curcas. This is likely one of the reasons for the very low yields, which, among other causes, led to the abandonment of J. curcas plantations in the region.


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