• Korean journal of applied entomology
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• v.27 no.2
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• pp.81-86
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• 1988

Experiments were conducted to investigate the locational and ovipositional preferences of the single and mixed populations of the brown planthopper(BPH), Nilaparvata lugens (Stal), and the whitebacked planthopper(WBPH),Sogatella furcifera (Hovath), with the different popula-tion densities at seeding, max-tillering, booting and heading stages of rice variety seonam by대. The WBPH showed a locational preference for the upper portion while the BPH was observed to stay generally on the lower portion regardless of rice growth stages, population density-levels and the single or the mixed populations of two species. At seeding, max-tillerinf, boo-tring and heading stage, the preference for the lower portion of the rice plants was found to be slighty reduced with the lapse of time, respectively, from the single or the mixed popula-tions of both the species. Ovipositional lication of both the species was found not to be affected by the different population densities at rice growth stage. Although the BPH prefered a ovi-positional location for the lower portion at seeding, booting and heading stages, its preference-was somewhat reduced with the developmental stages of rice plants, whereas the WBPH showed a ovipositional preference for lower portion at seeding stages, but prefered the same tendency of ovipositional preference for the upper and the lower portion, The location and ovipositional preferences were likely to be affected by the competition between species with the mixed populations rather than single.

• Korean journal of applied entomology
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• v.15 no.1 s.26
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• pp.23-27
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• 1976

Screenhouse experiments were conducted to find out the varietal difference in ovipositional preference of the striped rice borer moths (Chilo suppressalis W.) on eight varieties of rice and its association with several plant morphological characters. The results indicated the strong preference of the moths for ovipositing on several varieties. The varieties Tongil (Suweon 213-1), Yushin, Jinheung and TKM-6 had comparatively more egg masses and more eggs than the varieties IR-26, IR-747, Rexoro and Juckna. The strong ovipositional preference of moths of Tongil, as compared to the resistant variety TKM-6 and the susceptible variety Rexoro, was. always consistent in this study whenever the number of tillers were uniformed and each two varieties were paired. It could be concluded that the moths definitely preferred Tongil among the test varieties. There was not any significant correlations between the ovipositional preference and the plant characters; such as number of tillers per plant, plant height, external diameter of stem, and size of leaf. The cause of strong perference of the moths for ovipositing on short type varieties Tongil and Yushin were still suspectable.

• Journal of Ginseng Research
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• v.13 no.2
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• pp.174-177
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• 1989

The ovipositional preferences of Holotrichia morosa were investigated to defermine several environmental factors related to its incidence in ginseng fields. H. moroia paid no eggs in naked soil without ground color plants, and shouted ovipositional preference among weed plants in the order to Aurmisin prinrcps var oripntnlis, Epigrren canadensis Diuitarin sanguinalis, and Porttulaca oleracea. More oviposition was observed in the denser vegetation of D. sanguinalis and in soft soil. The egg-laying females were seldom attracted to fresh rice straw mulched on soil surface or decayred rite straw mixed into soil. The number of eggs laid by a female decreased considerably when the soil moisture content was below 5% or above 35%.

• Korean journal of applied entomology
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• v.15 no.4 s.29
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• pp.179-184
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• 1976

Laboratory experiments were conducted to clarity the early-spline host·selectivity by the small brown planthopper(SBPH), Laodelphax striatellus Fallen, and green rice Leafhopper(GLH), Nephotettix cincticeps Uhle., on the bailey (the variety Suweon #18) and water foxtail (Alopeculus aequadis Sosbol). The host selectivity was evaluated on the bases of feeding and ovipositional perferences of the insects on the plants and their biological effects on the plants. The nymphs of SBPH much more preferred barley for feeding than water forxtail, while the nymphs of GLH relatively prefered water foxtail. There was no significant difference in ovipositional preference by SBPH among the test plants, and ovipositional preference by GLH Ivas significantly lower on barley and water foxtail than on rice. Nymphal growth an4 adult emergence of SBPH were significantly faster and higher on barley than on water foxtail. No adult emergence of GLH was observed on barley, and adult emergence was still quite lower even on water foxtail. The adult of SBPH fed on barley showed longer longevity aad higher fecundity than that of SBPH from water foxtail and rice. The adult GLH fed ell water foxtail shorted relatively shorter longevity and to)ver fecundity than that of GLH on rice. In conculsion, barley seems to be more adequate for spring host of SBPH than water foxtail, but barley may not be quite adequate for spring host of GLH. At presont moment, GLH seems rather to primarily select the water foxtail than barley as a spring host, even if the water foxtail is not so adequate for development of GLH.

• Korean journal of applied entomology
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• v.14 no.4 s.25
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• pp.214-214
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• 1975

This study was conducted to evaluated the nature of the variety Tongil(Suweon 213-1) in resistance to the striped rice borer, Chilo suppressalis Walker, comparing with those of Rexoro(susceptible check) and TKM-6(resistant check) selected at IRRI. 1. The striped rice borer moths much more preferred the variety Tongil for oviposition than the varieties Rexoro and TKM-6. The variety Tongil and more egg masses and number of eggs than the varieties Rexoro and TKM-6, while TKM-6 having more egg masses and more number of eggs than Rexoro. This reaction was consistent throughout the test regardless of the number of tillers per hill. 2. In laboratory, preference of larvae for feeding was studied with 5cm of stem pieces of the varieties. The results showed, in contrast to the case of ovipositional preference, that the striped rice borer larvae least preferred the stems of Tongil among the test varieties, while larvae much more preferred the stems of Rexoro than those of TKM-6. 3. The larval weights at 20 days later infested on the 40 day-old plants were the lowest on Tongil among the test varieties. On the variety Rexoro the larvae had heavier body weights(43.0mg), higher pupation(64.9%) and higher adult emergence(83.3%) than those on Tongil(larval weights 30.3mg, pupation 60%, adult emergence 60.7%) and TKM-6(larval weights 35.7mg, pupation 56.3%, adult emergence 51.9%). The pupal weights, however, were not consistent among the test varieties and/or sexes in comparison with the larval weights, pupation and adult emergence above mentioned. 4. Field experiments indicated that the incidence of dead hearts at 70 days after transplanting was relatively higher on the variety Tongil(11.1%) than those on Rexoro(8.9%) and TKM-6(8.4%), and the incidence of white heads at harvest was, in contrast to the dead hearts, lower on Tongil(9.8%) than those on Rexoro(27.4%) and TKM-6(13.9%). At harvest lower larval survival observed on Tongil (49 larvae/40 hills) than those on the susceptible variety Rexoro(104 larvae/40 hills) and on the resistant variety TKM-6(70 larvae/40 hills). The average larval weights collected from three test varieties at harvest were 80.5mg from Tongil, 83.7mg from TKM-6 and 99.6mg from Rexoro. 5. Increased nitrogen fertilizer application to the variety Tongil, the striped rice borer damage was increased. Also, preference of larvae for feeding significantly increased with the increase of nitrogen fertilizer application. 6. Any specific association between the plant characters and striped rice borer resistance could not be found. The variety Tongil even having large number of tillers, short plant height, large stem, broad leaf, etc, had still high preference of moths for oviposition, low preference of larvae for feeding, low damage, and relatively high antibiosis. 7. Resistance of the variety Tongil to the striped rice borers seemed to be associated with the low feeding preference and the relatively high antibiosis, not associated directly with the ovipositional preference.

• Korean journal of applied entomology
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• v.12 no.2
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• pp.83-87
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• 1973

Experiment was conducted to study resistance of rice varieties and lines originated from Korea and IRRI sources to the zigzag-striped leafhopper, Recilia (Inazuma) dorsalis MOTSCHULSKY The nature of varietal resistance to the insect was evaluated from the viewpoints of feeding and ovipositional preferences and antibiosis. The varieties Su-Yai-20, Muthumanikam, PTB-18 and Vellanlangalayan were resistant and DV-139 moderately resistant to tile zigzag-striped leafhopper, and the other varieties tested were susceptible. Feeding and ovipositional preferences were significantly different among the varieties, but no correlation was observed between the two preferences. The nature of resistance of rice to the insect seemed to be related with The non-feeding preference, not non-ovipositional preference. The resistant (Vellanlangalyan and Su-Yai 20) and moderately resistant(DV-139) varieties had high antibiosis against the zigzag-striped leafhopper.

• Korean journal of applied entomology
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• v.14 no.1 s.22
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• pp.13-21
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• 1975

Experiments were conducted to select the new varieties and or/lines of rice resistant to the green rice leafhopper, Nephotettix cincticeps Uhler, and to evaluate the nature of their resistance to the insects in connection with the antibiosis and feeding and ovipositional preferences. The materials tested in this study were the varieties and or/lines of rice mostly proposed by the International Insect Resistance Nursery of IRRI and some others also orginiated from IRRI. Out of the 48 varieties and or/lines the 9 were selected as resistant and the 11 as mderately resistant. They have high antibiosis to the insects, showing significantly higher nymphal mortality and less adult emergence in the resistant and moderately resistant ones than the susceptible and moderately susceptible varieties Jinheung and Tong-il. Feeding perference was significantly different between the resistant and susceptible rice plants, resulting in much lower on resistant ones and much higher on susceptible ones. Ovipositional preference, however, was not different at all between the resistant and the susceptible ones. The nature of varietal resistance of rice to the green rice leafhopper seemed to be surely associated with the antibiosis and non-feeding preference.

• Korean journal of applied entomology
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• v.13 no.1 s.18
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• pp.11-16
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• 1974

Experiment was conducted to select the rice varieties and lines resistant to the smaller brown planthopper, Laodelphax striatellus Fallen, and study the cause of varietal resistance to the insect. The nature of varietal resistance was evaluated from the viewpoints of feeding and ovipositional preferences and antibiosis. Among the IRRI sources the varieties H 105, Muthumanikam, Vellailangalayan, Karsamba Red ASD-7. Manavari Co 22, Mudgo, PTB-18, IR 8 and IR 20 were selected as resistant sources. Among the domestic sources. only Suweon 213-1, Suweon 214 and Suweon 215 originated from the IR667 lines were resistant, and other leading varieties ail susceptible. The cause of resistance of rice to the insect seemed to be highly related with the non-feeding preference, not non-ovipositional preference. Nymphal mortality and rate of adult emergence were significantly different from the resistant and susceptible varieties. The rate of adult emergence was significantly lower in the resistant than In the susceptible varieties. The primary cause of lower adult emergence seemed to be due to the fact that the infects were suffered higher nymphal mortality in the resistant than in the susceptible varieties.

• Korean journal of applied entomology
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• v.12 no.1
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• pp.47-53
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• 1973

Experiments were conducted to study resistance of rice varieties originated from Korea·and IRRI-sources to the green rice leafhopper, Nephotettix cincticeps UHLER. The nature of varietal resistance to the insect was evaluated from the viewpoints of ovipositional and feeding preferences and antibiosis. A trial was also made to survey local biotypes o( the green rice leafhopper possible to show different reaction for the rice varieties. The varieties resistant to the green rice leafhopper were mostly IRRI sources such as Bir-tsan-3, MTU-15, DK-1, DV-139, H105, ASD-7, MGL-2, PTB-18, Muthumanikam, Vellanlangalayan, and the domestic commercial varieties were generally susceptible, but only the reaction of Tong-il and its lines were moderate. Ovipositional and feeding preferences were significantly different among the varieties, but no correlation was observed between the two preferences. The nature of varietal resistance to the insect seemed to be related with the feeding preference, not ovipositional preference. The green rice leafhoppers confined on the resistant varieties such as PTB-18, Muthumanikam, H105 etc. suffered higher nymphal mortality than the susceptible varieties such as T(N) 1 and Jinheung. Though the varieties Mudgo and Suweon 214 were moderately resistant and moderate in plant reaction, the insects confned on two varieties suffered relatively higher nymphal mortality. No local biotypes of green rice leafhoppers with respect to plant reaction were found.

• Korean Journal of Environmental Agriculture
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• v.27 no.3
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• pp.274-278
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• 2008

Paratlanticus ussuriensis oviposited from early July to mid-September under laboratory condition. A female laid on average 145 eggs during the period of reproduction and over 54% of the eggs were laid within 2 weeks after the first laying. The average depth of egg-laying in soil was 19.4 mm under surface. The average major axis of an egg was 5.7 mm and the minor axis was 2.0 mm. Just before hatching, the egg swelled about twice the weight of a newly laid. In tests of ovipositional preference in different types of media, more eggs were laid in soil than in vermiculite or in $Oasis^{(R)}$ floral form. Females also prefer shaded places in the field for reproduction, away from sunshine. In terms of the strategy for egg survival, adult moves to the hill-side adjacent to orchard farm to find a proper place for their egg laying and its survival in winter.