scholarly journals Effect of variety and planting date of rice on population of natural enemies of brown planthopper, Nilaparvata lugens (Stal)

2014 ◽  
Vol 6 (2) ◽  
pp. 409-415 ◽  
Author(s):  
A. S. Tetarwal ◽  
Lakhi Ram ◽  
Ram Singh ◽  
Manoj Kumar Jat
Keyword(s):  
Natural Enemies ◽  
Brown Planthopper ◽  
Nilaparvata Lugens ◽  
Planting Date ◽  
Reverse Trend ◽  
Significant Difference ◽  
The Mean ◽  
Nilaparvata Lugens Stål

The present study on the effect of variety and planting date of rice on population of natural enemies of brown planthopper, Nilaparvata lugens (Stal) showed that during August, the mean population of spiders was statistically on par on CSR 30 and PR 114. The population differed with dates and was significantly (p=0.05) higher (9.0/10 hills) in D2 during 2011 only. There was no significant difference in the population of spiders on two varieties and dates of transplanting during September 2011 only. However, significantly higher population of spiders was recorded in variety PR 114 (21.65/10 hills) and D2 (20.52/10 hills) than on CSR 30 (13.67/10 hills) and D1 (14.80/10 hills) during September, 2012. The mean population of spiders did not differ significantly with the dates during October, 2011 and 2012. However, it was significantly higher on variety PR 114 (27.65/10 hills) than on CSR 30 during both the crop seasons. Mirid bugs did not appear in the month of August, 2011 and 2012 whereas during September 2011, the variety CSR 30 and D1 registered significantly higher population than other variety and date. However, a reverse trend was observed with varieties and dates during 2012. The mean population of coccinelid, carabid and staphylinid beetles remained very low on both the varieties in the month of August during 2011 and 2012. However, the population of these predators was influenced significantly by the varieties and dates during 2012. The population of nymphal-adult parasitoids also remained very low during both years and was not influenced by varieties and dates.

scholarly journals Kepadatan Populasi Wereng Coklat (Nilaparvata lugens, Stal.) dan Musuh Alaminya Pada Berbagai Varietas Padi di Bantul Yogyakarta

2021 ◽  
Vol 1 (2) ◽  
pp. 45-48
Author(s):  
Darmawan Suryo Sudarsono
Keyword(s):  
Population Density ◽  
Natural Enemies ◽  
Rice Field ◽  
Brown Planthopper ◽  
Nilaparvata Lugens ◽  
Resistant Variety ◽  
Local Varieties ◽  
Hybrid Variety ◽  
Nilaparvata Lugens Stål

A research to observe the population density of brown planthoppers (Nilaparvata lugens, Stal.) and their predator and parasitoid natural enemies has done on the rice field in Bantul regency of Yogyakarta. The research was conducted to observe the hoppers and its natural enemies on three local varieties and one superior brown planthoppers resistant variety of rice. The three local varieties of rice were Rejosari, Sri Kuning, and Sri Ayu, while the hopper resistant variety was IR 64. The observation were replicated three times. The result showed that population of brown planthoppers in the three local varieties of rice were higher than in the resistant IR 64 hybrid variety. The population of predators and parasitoid were relatively high in order to control the development of brown planthopper population. The predator Lycosa sp. and the parasitoids Anagrus sp.  were commonly found in the ecosystem.

scholarly journals Keragaan Sumber Kitin untuk Mempertahankan Virulensi Beauveria bassiana (Bals.), Jamur Pengendali Wereng Batang Cokelat (Nilaparvata lugens Stal.)

2018 ◽  
Vol 22 (2) ◽  
pp. 143
Author(s):  
Nova Laili Wisuda ◽  
Subur Sedjati
Keyword(s):  
Brown Planthopper ◽  
Nilaparvata Lugens ◽  
Potato Dextrose Agar ◽  
Spore Density ◽  
Colony Forming Unit ◽  
Randomized Design ◽  
Significant Difference ◽  
Lethal Time ◽  
Rice Medium ◽  
Nilaparvata Lugens Stål

Beauvaria bassiana is an entomopathogenic insect that effectively controls brown planthopper (BPH), but will decrease it virulences if nutrients containing chitin and protein is not added. The aim of this research is to find the best method of B. bassiana propagation with the addition of shrimp and cricket flour, both are chitin sources. Isolates were cultured with Potato Dextrose Agar (PDA) medium and continued with rice medium. This research method used non-factorial Completely Randomized Design (CRD) with three treatments consisting of control, addition of shrimp flour and addition of cricket flour per treatment each with six replications. The research parameters consist of percentage of mortality, percentage of  conidia rising time, and LT50 test. The chitin sources could increases the growth rate from 0.69 cm per day to 1.449 cm per day and increases the spore density by 4.8×106 CFU (Colony Forming Unit) up to 8.2×106 CFU. Chitin also affects the virulence of B. bassiana in BPH where it can increase the percentage of death starting from 3%until10% and made lethal-time of BPH faster from 0.25 to 0.45 day. There is no significant difference between the sources of chitin between shrimp and cricket flour, so it is more advisable to use cricket flour because it is less expensive. IntisariBeauvaria bassiana merupakan serangga entomopatogen yang efektif mengendalikan wereng batang cokelat (WBC), namun akan mengalami penurunan virulensi bila tidak diberikan nutrisi yang mengandung khitin dan protein. Penelitian ini bertujuan menemukan metode terbaik perbanyakan B. bassiana yang dilakukan dengan penambahan tepung ebi dan penambahan tepung jangkrik yang merupakan sumber kitin. Isolat dibiakkan dengan medium per- banyakan Potato Dextrose Agar (PDA) dan diteruskan hingga perbanyakan beras. Metode penelitian ini menggunakan Rancangan Acak Lengkap (RAL) non-faktorial dengan 4 perlakuan dan 6 ulangan yang terdiri atas kontrol, tanpa tambahan kitin, penambahan tepung ebi dan penambahan tepung jangkrik. Parameter penelitian terdiri persentase mortalitas, persentase waktu munculnya konidia dan uji LT50. Pemberian sumber kitin meningkatkan kecepatan pertumbuhan hingga 0,69−1,49 cm per hari dan meningkatkan kerapatan spora berkisar 4,8×106−8,2×106 CFU (colony forming unit). Kitin juga berpengaruh terhadap virulensi B. bassiana pada WBC dimana mampu meningkatkan persentase kematian 3−10% dan waktu paruh kematian WBC 0,25−0,45 hari lebih cepat. Tidak ada perbedaan yang berarti antara sumber khitin dari tepung jangkrik dan tepung ebi sehingga lebih disarankan untuk menggunakan tepung jangkrik karena lebih murah dan mudah didapat.

scholarly journals Physicochemical Properties and Bioactivity of a New Guar Gum-Based Film Incorporated with Citral to Brown Planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae)

Molecules ◽  
2020 ◽  
Vol 25 (9) ◽  
pp. 2044
Author(s):  
Xiubing Gao ◽  
Can Guo ◽  
Ming Li ◽  
Rongyu Li ◽  
Xiaomao Wu ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Guar Gum ◽  
Insect Pest ◽  
Brown Planthopper ◽  
Nilaparvata Lugens ◽  
Transmission Electron ◽  
Lower Solubility ◽  
Film Forming ◽  
Significant Difference ◽  
Nilaparvata Lugens Stål

The brown planthopper (BPH), Nilaparvata lugens (Stål), is the most notorious rice insect pest. In order to repel BPH effectively while being environmentally friendly, a new film based on guar gum incorporated with citral (GC film) was formulated. A toxicity bioassay of citral and guar gum at different proportions (ratios of 3:1, 2:1, 1:1, 1:2, and 1:3 in w/w) of GC film-forming emulsion to BPH was performed with the rice stem dipping method. Results showed that the most effective ratio of citral to guar gum was 1:1 with the median lethal concentration (LC50) of 4.30 mg/mL, far below the LC50 of guar gum (GG)/citral individual (141.51 and 44.38 mg/mL, respectively). The mortality of BPH adults and nymphs in the third instar treated with different dilution multiples of GC film-forming emulsion ranged from 46.67% to 82.22% and from 37.78% to 71.11%, respectively. These indicated that GC film-forming emulsion had a direct toxicity on BPH, and the mixture of citral and GG had synergistic interactions. Subsequently, Fourier-transform infrared spectroscopy showed that the incorporation of guar gum with citral was successful and did not result in the formation of new chemical bonds. The GC film exhibited a darker color and rougher surface topography with larger apertures and deeper gullies (Ra = 1.42 nm, Rq = 2.05 nm, and Rmax = 25.40 nm) compared to the guar gum film (GG film) (Ra = 1.00 nm, Rq = 1.33 nm, and Rmax = 16.40 nm), as determined by transmission electron microscopy and atomic force microscopy. The GC film exhibited a 50.4% lower solubility in water (30.30% vs. 15.00%) and 71.3% oxygen permeability (8.26 × 10−9 vs. 2.37 × 10−9 cm3/m2·d·Pa) (p < 0.05) but did not demonstrate any significant difference in mechanical properties, such as thickness (39.10 vs. 41.70 mm), tensile strength (41.89 vs. 38.30 N/mm2), and elongation at break (1.82% vs. 2.03%) (p < 0.05) compared to the GG film. Our findings established a link between physicochemical properties and bioactivity, which can provide useful information on developing and improving GC films and may offer an alternative approach for the control of BPH in the near future.

scholarly journals Heat Stress Impedes Development and Lowers Fecundity of the Brown Planthopper Nilaparvata lugens (Stål)

PLoS ONE ◽  
2012 ◽  
Vol 7 (10) ◽  
pp. e47413 ◽  
Author(s):  
Jiranan Piyaphongkul ◽  
Jeremy Pritchard ◽  
Jeff Bale
Keyword(s):  
Heat Stress ◽  
Brown Planthopper ◽  
Nilaparvata Lugens ◽  
Nilaparvata Lugens Stål

RNA interference-aided knockdown of a putative saccharopine dehydrogenase leads to abnormal ecdysis in the brown planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae)

2015 ◽  
Vol 105 (4) ◽  
pp. 390-398 ◽  
Author(s):  
P.-J. Wan ◽  
L. Yang ◽  
S.-Y. Yuan ◽  
Y.-H. Tang ◽  
Q. Fu ◽  
...  
Keyword(s):  
Brown Planthopper ◽  
Transcript Level ◽  
Nilaparvata Lugens ◽  
The Body ◽  
Double Stranded Rna ◽  
Saccharopine Dehydrogenase ◽  
Body Weights ◽  
Nilaparvata Lugens Stål ◽  
Phloem Feeding ◽  
Wing Deformation

AbstractThe brown planthopper Nilaparvata lugens is a serious phloem-feeding pest of rice in China. The current study focuses on a saccharopine dehydrogenase (SDH) that catalyzes the penultimate reaction in biosynthesis of the amino acid lysine (Lys), which plays a role in insect growth and carnitine production (as a substrate). The protein, provisionally designated as NlylsSDH [a SDH derived from yeast-like symbiont (YLS) in N. lugens], had a higher transcript level in abdomens, compared with heads, wings, legs and thoraces, which agrees with YLS distribution in N. lugens. Ingestion of Nlylssdh targeted double-stranded RNA (dsNlylssdh) for 5, 10 and 15 days decreased the mRNA abundance in the hoppers by 47, 70 and 31%, respectively, comparing with those ingesting normal or dsegfp diets. Nlylssdh knockdown slightly decreased the body weights, significantly delayed the development of females, and killed approximately 30% of the nymphs. Moreover, some surviving adults showed two apparent phenotypic defects: wing deformation and nymphal cuticles remained on tips of the legs and abdomens. The brachypterours/macropterours and sex ratios (female/male) of the adults on the dsRNA diet were lowered compared with the adults on diets without dsRNA. These results suggest that Nlylssdh encodes a functional SDH protein. The adverse effect of Nlylssdh knockdown on N. lugens implies the importance of Lys in hopper development. This study provides a proof of concept example that Nlylssdh could serve as a possible dsRNA-based pesticide for planthopper control.

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