• 한국조경학회지
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• 제31권4호
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• pp.74-81
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• 2003

The need for insect and mite resistant turfgrass cultivars arose because of problems associated with pesticide use. Representative cultivars and genotypes of 18 warm-season turfgrass [Zoysia japonica Steud., Z. japonica${\times}$Z. metrella hybrids, Z. japonica${\times}$Z. tenuifotia hybrids, Z. matrella (L.) Merr., Cynodon dactylon (L.) Pers., C. dactylon${\times}$C. transvallensis hybrids, Paspalum notatum Flugge., P. vaginatum Swartz., Stenotaphrum secundatum (Walt.) Kuntze, Eremochloa ophiuroides (Munro.) and Buchloe dactyloides (Nutt.) Engelm.] and 20 cool-season turfgrasses [Poa pratensis L., Festuca arundinacea Schreb., F. rubra L., F. rubra var. commutata Gaud., F. ovina var. duriuscula L. Koch. Agrostis tenuis Sibth., A. palustris Huds., and Latium perenne L.] were evaluated for host resistance to feeding by the Spodoptera depravata (Butler) in the laboratory. Two experiments were set up in the laboratory using 8.5cm diameter${\times}$4.0cm deep plastic petri dishes as larvae feeding chambers. In experiment 1, one neonate larvae were place on the grass in each dish and the dishes were arranged with 5 replicates each within an environmental chamber maintained at $25^{\circ}C$ and 15h light: 9h dark Larval survival and larval weights at 7d and 14d, pupal weights, and days to pupation were compared among turfgrasses. In Experiment 2, 4cm sections of all grasses were oriented equidistant from each other in a pattern resembling the spokes of a wheel. Five one neonate larvae were introduced to the center of each dish. Dishes were immediately placed in an environmental chamber held at $25^{\circ}C$, 15h light: 9h dark Larvae were allowed to feed for 24h. Damage was rated from 0(no damage) to 9(completely consumed) were made for eachturfgrass. Resistance as antibiosis (high mortality, slowed growth, and least preference) was identified in Z. japonica${\times}$Z. tenuifolia hybirids ‘Emerald’, Z. japonica${\times}$Z. metrella hybirds ‘Miyako’ and Eremochloa ophiuroides (Munro.). Cool-season turfgrasses tested were susceptible to feeding by Spodoptera depravata (Butler).

• 한국응용곤충학회지
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• 제19권2호
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• pp.85-89
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• 1980

1976년 본해충을 실내사육하면서 얻어진 결과는 다음과 같다. 1. 한 마리당 산란수는 $1202.0{\pm}150.6$개 산란전기간 $9.0{\pm}0.8$일 산란기간 $13.3{\pm}1.2$일 산란후기간은 $1.7{\pm}0.2$일이었고 산란시기는 일몰후였다. 2. 유충은 5령형과 6령형으로 구분할 수 있었고 5령형의 유충기간은 $15.36{\pm}1.59$일 용기간 $7.82{\pm}1.01$일 6령형의 유충기간은 $16.92{\pm}1.08$일 용기간 $8.23{\pm}1.09$일 이였으며 난기간은 2일 자성충 수명은 $21.29{\pm}3.15$일 웅성충은 $19.14{\pm}2.47$일이였다. 3. 령기별 두건은 5령형 $2.77\~21.89mm$ 5령형이 $2.78\~22.38mm$였다. 4. 두건을 logarithum으로 변형했을 때 령기에 따른 두건의 증가는 5령형이 $log \;y=0.228\chi+0.228(r=0.997)$, 6령형이 $log \;y=0.182\chi+0.259(r=0.999)$로 표현되어 고도의 정상관 관계였다.

• 한국농림기상학회지
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• 제25권1호
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• pp.37-47
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• 2023

The black cutworm, Agrotis ipsilon (Hufnagel), is an important crop pest worldwide that feeds more than 80 plant species including cabbage, potato, maize, wheat and bean, and this moth is a typical pest attacking underground parts of crops. It has been known in farm booklets that the larvae of A. ipsilon overwinter in the soil in Korea, but no definitive data exist yet. This study was conducted to evaluate that the specific appearance time of A. ipsilon observed actually in the field could be explained when we assumed that this pest overwinters in a form of larvae or pupae. Degree day-based phenology models were applied for tracking forward or backward to find the predicted developmental stage which developed at a specific stage found in the field. As a result of the analysis, it was confirmed that an initial population could be established in a group that does not overwinter as larvae or pupae in Korea. In other words, the appearance of adults in early March to April could not be explained by the presence of domestic overwintering populations. Populations that overwinter as larvae or pupae in Korea were able to emerge as adults in June to July at the earliest. Therefore, the group of adults appearing in early spring is highly likely to be a population that migrated from outside Korea. Taken together, it was estimated that the colony of A. ipsilon in Korea would be formed by a mixture of a migrant population through long-distance migration and a overwintering population.