scholarly journals Studies on mycosis of Metarhizium (Nomuraea) rileyi on Spodoptera frugiperda infesting maize in Andhra Pradesh, India

2020 ◽  
Vol 30 (1) ◽  
Author(s):  
M. Visalakshi ◽  
P. Kishore Varma ◽  
V. Chandra Sekhar ◽  
M. Bharathalaxmi ◽  
B. L. Manisha ◽  
...  

Abstract Background Mycosis on the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), infecting maize was observed in research farm of Regional Agricultural Research Station, Anakapalli from October 2019 to February 2020. Main body High relative humidity (94.87%), low temperature (24.11 °C), and high rainfall (376.1 mm) received during the month of September 2019 predisposed the larval instars for fungal infection and subsequent high relative humidity and low temperatures sustained the infection till February 2020. An entomopathogenic fungus (EPF) was isolated from the infected larval instars as per standard protocol on Sabouraud’s maltose yeast extract agar and characterized based on morphological and molecular analysis. The fungus was identified as Metarhizium (Nomuraea) rileyi based on ITS sequence homology and the strain was designated as AKP-Nr-1. The pathogenicity of M. rileyi AKP-Nr-1 on S. frugiperda was visualized, using a light and electron microscopy at the host-pathogen interface. Microscopic studies revealed that all the body parts of larval instars were completely overgrown by white mycelial threads of M. rileyi, except the head capsule, thoracic shield, setae, and crotchets. The cadavers of larval instars of S. frugiperda turned green on sporulation and mummified with progress in infection. In vitro pathogenicity tests revealed the potential of AKP-Nr-1 strain of M. rileyi in management of S. frugiperda. Short conclusion The results indicated the potential of M. rileyi AKP-Nr-1 as biocontrol agent for management of the fall armyworm. This AKP-Nr-1 strain of M. rileyi needs further evaluation under field conditions to evaluate its efficacy against S. frugiperda and its effects on other hosts.

2020 ◽  
Vol 5 (1) ◽  
pp. 41-42
Author(s):  
Moses Otuba ◽  
Jumrae Cho

Most cereal crops are often damaged by lepidopterous insects. Of recent, fall armyworm, S. frugiperda (J.E. Smith) has resulted into yield and economic loss in many African and Asian countries. This reduces farmers’ income drastically and to overcome this damage, pesticides have been used which are not also environmentally friendly. Experiments were set up to collect data on the potential of three larval predators Orius strigicollis, Micromus angulatus, and Podisus maculiventris against S. frugiperda. The consumption of S. frugiperda larvae by three predators had highly significant effects (P≤0.05) on first, fourth, and sixth instars. No significant difference was reported between M. angulatus and O. strigicollis on second, third and fifth larval instars of S. frugiperda. O. strigicollis consumed more first larval instar (6.2±0.71) of S. frugiperda than M. angulatus (4.9±1.07) and P. maculiventris (4.2±0.74). However, P. maculiventris consumed more second to sixth larval instars of S. frugiperda than other two predators (O. strigicollis and M. angulatus). The predator P. maculiventris is recommended for controlling S. frugiperda in their second to sixth larval instars while O. strigicollis in the first larval instar. It can be also concluded that fourth larval instars of S. frugiperda is more suitable for its control using predator P. maculiventris as compared to other larval instars. This study therefore recommends predator Podisus maculiventris to be used in control of S. frugiperda under laboratory conditions.


1970 ◽  
Vol 6 ◽  
pp. 84-88
Author(s):  
Mukesh Karki

The present study on body weight and feed efficiency for growth was carried out on 112 turkeypoults from day of hatch to 28 weeks of age during May to November 2002 at Poultry ResearchUnit of Regional Agricultural Research Station (RARS)-Parwanipur. Layer starter rationsupplemented with 6% fish meal + 0.3% lysine + 0.125% methonine was fed up to 8 weeks ofage, then after layer finisher diet was fed. The body weight, feed consumption was observed at 4weekly interval and feed efficiency and economics of rearing period in terms of income overfeed and poults cost was calculated. Significant increase in body weight was recorded up to 28weeks in male and 20 weeks in female. Male turkey had significantly higher body weight thanthat of female in all ages. Feed efficiency is best at earlier age but up to 16 weeks it is 3.77 formale after that it detoriates progressively. Male turkey exhibited better feed efficiency than thatof female for all weeks. Significantly higher return per bird was obtained from male than that offemale in all age. The profit per bird for both male and female was found maximum in 16 weeksof rearing, followed by 20 weeks and 24 weeks. Therefore, instead of waiting for highest bodyweight, it is better to sell turkey at 16 to 20 weeks of age to take maximum advantage of higherweight gain, higher efficiency of feed utilization and higher profit.Key words: Economics; feed utilization; growth; rearing period; turkeyDOI: 10.3126/narj.v6i0.3369Nepal Agriculture Research Journal Vol.6 2005 pp.84-88


2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Wandee Wattanachaiyingcharoen ◽  
Ongpo Lepcha ◽  
Apichat Vitta ◽  
Det Wattanachaiyingcharoen

Abstract Background Under laboratory and greenhouse conditions, the virulence of 2 isolates of Thai indigenous entomopathogenic nematodes (EPNs) in controlling the fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) (Lepidoptera; Noctuidae), was demonstrated. Six EPNs dosages were tested against 2 larval instars of FAW under the laboratory conditions, while 2 different concentrations were tested under the greenhouse conditions. Results The results of a laboratory experiment revealed that 2 Thai indigenous EPNs isolates (Heterorhabditis indica isolate AUT 13.2 and Steinernema siamkayai isolate APL 12.3) were efficient against the FAW, 2nd and 5th larval instars. Six different nematode concentrations (50,100, 150, 200, 250 and 300 infectious juveniles (IJs) ml−1) were evaluated, and all were proven to be effective, with the mortality rate associated with concentration. Inoculated larvae in the 2nd instar was more vulnerable than that in the 5th instar. H. indica isolate AUT 13.2 was more destructive than S. siamkayai isolate APL 12.3. The greatest mortality rate of 2nd instar larvae was 83% when H. indica AUT 13.2 was applied at the concentration of 250 IJs ml−1, and 68% when the nematode S. siamkayai APL 12.3 was used at the concentration of 300 IJs ml−1. At 250 IJsml−1, the highest mortality rate of the 5th instar larvae was 45% for H. indica AUT 13.2 and 33% for S. siamkayai APL 12.3, respectively. To customize the concentration and volume of nematodes suspension evaluated in the greenhouse settings, the most sensitive stage of FAW and the optimum concentration that caused the highest mortality were used. The concentrations of both indigenous nematodes’ isolates were 20,000 and 50,000 IJsml−1 per pot, respectively, and the results showed that the mortality rates were lower than that in the laboratory. FAW mortality rate was the highest (58%) in case of the nematode H. indica isolate AUT 13.2, against (45%) in case of S. siamkayai isolate APL 12.3, at the 50,000 IJs ml−1 concentrations. Conclusions The study revealed the 2 Thai indigenous EPNs isolates (H. indica isolate AUT 13.2 and S. siamkayai isolate APL 12.3) were capable of controlling the FAW in both laboratory and greenhouse environments. The 2 Thai EPNs showed the potential to be considered as a biological control agent.


Author(s):  
R. Sunitha Devi ◽  
S. G. Mahadevappa

The field experiments were conducted during kharif season of year 2014 & 2015 at Agricultural Research Station, Rajendranagar, Hyderabad, Telangana state, India to study the influence of weather parameters on the incidence of thrips population on Bt cotton. The results revealed that the peak incidence of thrips population was recorded on 35th Standard Week i.e., last week of August (32.87 thrips leaf–1) during kharif, 2014 and two peaks i.e., 35th Standard Week i.e., last week of August (33.93 thrips leaf–1) and 40th  Standard Week i.e., the first week of October (40.40 thrips leaf–1) were recorded during kharif, 2015. Thereafter, its population declined gradually during both seasons. Correlations worked out between thrips population and weather parameters revealed that, one week (0.51*) and two weeks lag (0.65**) minimum temperature, one week lag (0.56**) morning relative humidity showed significant and positive influence, while one week lag (–0.44*) evaporation showed significant negative influence on thrips incidence. The prediction model developed for the thrips population revealed that the model explained the variation to an extent of 54 per cent in thrips incidence under the influence of minimum temperature and morning relative humidity.


2020 ◽  
Vol 12 (2) ◽  
pp. 157-164
Author(s):  
S. Gahatraj ◽  
S. Tiwari ◽  
S. Sharma ◽  
L. Kafle

Abstract. Fall Armyworm (FAW), Spodoptera frugiperda, is an invasive pest of maize including other cultivated crops such as rice, wheat, and many other vegetables. This invasive species was initially noticed in North-America and later reported in many countries of Africa in early 2016. In South Asia, this has been reported for the first time in India followed by Srilanka in 2018 and Bangladesh, China, Taiwan and Nepal in 2019. It is polyphagous in nature and damage has been reported in more than 80 plant species. The loss has to lead up to 50-80% in maize in severe situation. FAW is a distant flyer and can fly more than 100 km in a night and spread well in crop fields. As this pest is already invasive in many states of India and the likelihood of entry and spreading in Nepal is higher because of the open border between the countries and flexible government quarantine policy. The great socio-economic loss has been forecasted once this pest has received invasive status in Nepal. Recently, this crop has been confirmed by Nepal Agricultural Research Council (NARC) in Gaidakot area of Nawalpur district, Nepal and has been noticed in almost all parts of Nepal such as Sidhuli, Chitwan, Nawalparasi, Tanahun and Rupendehi districts. However, this information has not been endorsed by Nepal Plant Protection Office (NPPO), an official invasive species endorsing organization in Nepal. This species is spreading rapidly in maize growing areas and significant losses have been reported in maize crop by the farmers. The regular scouting, surveillance, and monitoring can be suggested to evaluate the pest status in the crop field. Habitat manipulation with the deployment of deterring crops ‘push’ such as desmodium (Desmodium uncinatum) and pest-attracting crop ‘pull’ such as Napier (Pennisetum purpureum) and Sudan grass (Sorghum vulgare sudanense) is suggested in a ‘push-pull strategy’, the most popular and successful method of FAW management in the maize field. Field sanitation, and conserving pest’s natural enemies are other integrated approaches. However, in a commercial maize field, a group of ‘soft’ and selective chemicals have been suggested for immediate control of this pest. This review compiled the recent informations available on FAW and is useful for farmers, researchers and policy makers to draw a roadmap for the future FAW management in Nepal.


2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Hrang Chal Lalramnghaki ◽  
Lalramliana ◽  
Hmar Tlawmte Lalremsanga ◽  
Vanlalhlimpuia ◽  
Mary Lalramchuani ◽  
...  

Abstract Background Outbreak of the fall armyworm Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) occurred in Mizoram, North-Eastern India. The infestation spread in the entire state covering a total area of around 2840 hectares of maize cultivated land. Entomopathogenic nematodes (EPNs) represent potential candidates for the biological control of S. frugiperda. In the study, the susceptibility of the pest against 4 locally isolated EPN species Heterorhabditis indica, H. baujardi, Steinernema sangi and S. surkhetense was evaluated. Results The results indicated that all the isolated EPN species showed a high rate of larvicidal and pupicidal activities against the pest. Mortality between 43.75–100.00 and 25.00–100.00% of 3rd and 5th larval instars, respectively (at concentrations 10–800 IJs/larva), and 37.50–68.75% mortality of pupae (at concentrations 200–1600 IJs /pupa) were found after exposure to the EPN species. The mortality rate of the pest showed significant variations with life stages of the host insect, nematode concentrations and incubation time. Based on the median lethal concentration (LC50), H. indica was the most pathogenic species, followed by S. sangi, H. baujardi and S. surkhetense. The LC50 values of H. indica at 72 h post-incubation were 20.26 and 62.07 IJs/larva for the 3rd and 5th larval instars, respectively, and 913.34 IJs/pupa. The penetration assay showed that H. indica had the highest penetration rate into the hosts, 27.24, 21.30 and 20.00% in the 3rd, 5th larval instars and pupae, respectively. Furthermore, all the EPN isolates were capable of successful multiplication inside the cadaver of S. frugiperda that showed significant differences with the EPN isolates and life stages of the pest. Among the isolates, H. indica showed the highest multiplication rates, 17,692.25 ± 2103.59, 8345.63 ± 785.34 and 79,146.38 ± 5943.73 IJs per 3rd instar larva, 5th instar larva and pupa, respectively. Conclusions The study revealed that the 4 species of EPNs showed a high potency against S. frugiperda, thereby having the potential to be developed as a biological control agent against the pest. Moreover, the isolated EPN species could potentially serve as alternatives for chemical insecticides and could further be incorporated into the Integrated Pest Management (IPM).


2017 ◽  
Vol 26 (1) ◽  
pp. 51
Author(s):  
R Chitra, P Hemalatha

The initial growth of turmeric is rather slow and takes about 4-5 months to cover the inter space. Therefore, the available space between the rows of turmeric could be effectively utilized by growing short duration crops like, vegetables, cereals etc. Hence, it is worthwhile to explore the possibilities of growing compatible crops with turmeric. With this background the experiment on effect of intercrops on growth and yield of turmeric was conducted at Agricultural Research Station, Bhavanisagar. Among the different intercrops, turmeric with cowpea recorded the maximum fresh rhizome yield per hectare (30.78 t ha-1) while turmeric + bhendi registered the maximum B:C ratio (2.68:1). Monocropping of turmeric recorded the lowest B:C ratio (1.67:1) among all the treatments.  


2020 ◽  
Vol 51 (4) ◽  
pp. 1139-1148
Author(s):  
Othman & et al.

The research work was conducted in Izra’a Research station, which affiliated to the General Commission for Scientific Agricultural Research (GCSAR), during the growing seasons (2016 – 2017; 2017 – 2018), in order to evaluate the response of two durum wheat verities (Douma3 and Cham5) and two bread wheat varieties (Douma4 and Cham6) to Conservation Agriculture (CA) as a full package compared with Conventional Tillage system (CT) under rainfed condition using lentils (Variety Edleb3) in the applied crop rotation. The experiment was laid according to split-split RCBD with three replications. The average of biological yield, grain yield,  rainwater use efficiency and nitrogen use efficiency was significantly higher during the first growing season, under conservation agriculture in the presence of crop rotation, in the variety Douma3 (7466 kg. ha-1, and 4162kg. ha-1, 19.006 kg ha-1 mm-1,  39.62 kg N m-2respectively). The two varieties Douma3 and Cham6 are considered more responsive to conservation agriculture system in the southern region of Syria, because they recorded the highest grain yields (2561, 2385 kg ha-1 respectively) compared with the other studied varieties (Cham5 and Douma4) (1951 and 1724 kg ha-1 respectively). They also exhibited the highest values of both rainwater and nitrogen use efficiency.


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