• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.2
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• pp.93-97
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• 1977

The rate of damaged soybean seeds by pod borer averaged 7.4% with the range of 1.2%-21.3% and tended to be higher in the lines with hairy pods comparing to those with hairless pods. The susceptibility of pod borer was negatively correlated with the pod setting date. while was not significantly affected by the weather conditions during the pod setting period.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.357-362
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• 2010

Soybean seed injury was analyzed in the experiments in which the bean bug, Riptortus pedestris(Hemiptera: Alydidae), was released into screen-caged pots containing full seed stage(R6) of soybean. When the different stages of insects, from the 3rd instar nymphs to adults, were released into pots during 8 days in soybean R6 stage, soybean seeds with injury marks (B-type seeds) increased. The weight reduction ratio in B-type seeds was highest in the injury by the 5th instar nymphs, while the daily-produced number ratio of B-type seeds was small in the treatment. In the injury by the different number of adult released into pots, 4, 8, 16 adults caused a significant increase of B-type seeds, while 16 adults caused the significant increase of the deformed (C-type) seeds. In the injury by the different release period of adults, the total number of pods was not significantly different among treatments, while the total seed number harvested was significantly small in the release for 48 days. The release for 8 and 16 days caused a significant increase of B-type seeds, while the release for 48 days caused the increase of C-type seeds. The results indicated that injury of soybean R6 stage by the bean bug produced soybean seeds with distinct injury marks at relatively low density and during short term attack period, while it produced deformed seeds at high density and during long attack period.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.1
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• pp.46-54
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• 1993

On the purpose to increase the cultivation stability of the hulless waxy barley which is unstable in the northern region of Korea, the effects of genes of hulled /hulless and waxy /nonwaxy on seedling emergency was studied by using four isogenic lines of hulled -waxy, hulless -waxy, hulled -nonwaxy and hulless -nonwaxy barley. The germination rates of hulless lines lowered by four to six percent compared with those of hulled counterparts with one day's rainfall just before harvest, and were much deteriorated with raining prolonged. The gaps between emergency rates of hulless lines and their counterparts were greater than those of germination rates, and the differences increased as the seeding depths were deepened. The emergency rates of hulless lines were affected in the order of seeding depth, rotation speed of thresher and preharvest rainfall. Waxy endosperm gene did not show any significant effects on the damage of grain during threshing. It seems that the embryos of hulled lines were less damaged than those of hulless ones during threshing due to the protecting effects by husks. When grains were threshed with thresher of 600rpm or 900rpm and dehulled with dehuller of 750rpm, any significant depreciations such as broken seeds and decreased germination rate did not occured in hulled lines. But the grains of hulless lines received some damages with the rotation speeds, especially germination rates decreased seriously when the rotation speed of de huller was high. Prehavest sprout rates of the lines incorporated with the waxy genes were higher than those with nonwaxy genes whereas the genes of hulled and hulless did not give any significant effects.