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The western cherry fruit fly (CFF), Rhagoletis indifferens Curran, is a major pest of cherries. Because of a ‘zero tolerance' for damage, detecting CFF emergence is critical for successful control. To improve predictions of CFF emergence, historical observations on first emergence, rainfall, and temperature were analyzed. The amount of precipitation in March found to accelerate the first CFF emergence. In average, CFF emerges 9 days earlier in The Dalles than in Hood River, however, the heat unit (degree days, DD) were required 71DD more in The Dalles then in Hood River. A CFF phenology model was developed based on the time varying distributed delay concepts. The model can simulate the whole phenology system including post-diapause pupal development, adult emergence, egg-laying, and larval development in user friendly menu driven system. The model also has the capability to simulate the effect of control measures on the CFF population. The model predicts field population when compared to the trap catch records last few years, however, some essential biological information was needed for inclusion in this model to make it more biologically meaningful and reliable. From the simulation, a simple heat requirement values (DD) for the first emergence were estimated as 480DD in The Dalles and 550DD in Hood River for the site-specific prediction.

In southern Korea, the two aphid species, Myzus pessicae (Sulzer) and Lipaphis pseudobrassicae (Davis), had been known to have sexual phase to produce hibernating eggs on their alternate hosts. However, we have frequently found that they were still alive in the parthenogenetic form even in below freezing conditions in winter. This study had been focused on verifying the possibility of overwintering of the two important aphid species in the parthenogenetic morph, by comparing the population density changes within greenhouse and open field condition. In greenhouse condition, though not heated, both species successfully continued reproducing in a parthenogenetic form. In open field, L. pseudobrassicae successfully survived and reproduced on chinese cabbage and spinach even below freezing temperatures. M. persicae were also able to survive in the winter but not as much capability of reproduction as L. pseudobrassicae. This study provided the evidence that the aphid infestations in greenhouse can be mostly from overwintering populations in the parthenogenetic morph in southern greenhouse area of Korea.

We conducted a study on the population dynamic of the two major aphid species of green peach aphid, Myzus persicae (Sulzer), and cotton aphid, Aphis gossypii (Glover), as well as their natural enemies on the five major green house crops in Chinju greenhouse vegetable area in Korea. The green peach aphid was relatively the majority among all aphids collected from tomato, potato, and chinese cabbage, while the cotton aphid was major species on water melon and hot pepper. Both species reached their peaks in mid June, when the summer monsoon was not initiated, the temperature was relatively as low as 23°C, and the crops were young and favorable. The density of predators such as spiders, lady beetles and green lacewings and some other arthropods were very low in the early season and reached their pick three weeks after the aphids density peaked. This data indicated that the predators only follow aphid abundance but arrive too late to be effective as regulators of aphids population. About 9,255 samples of various aphids collected from the five crops, we found 39 parasitoids representing at least eight different species. Aphidiid sp. occupied 35.8% and hyperparasites occupied 56.5%. Lipolexis scutellaris species was very scarce and only occupied 2.6% from Aphis gossypii on watermelons. This information can be used for determining the impact of natural enemies under the mixture of greenhouse-open field vegetable production system.