• Korean Journal of Soil Science and Fertilizer
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• v.22 no.3
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• pp.228-233
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• 1989

Successive changes of transpiration by the tobacco plant during the growing season with pot trial treated with 30cm and 100cm ground water tables were compared with change of soil moisture content in rhizospere of field under natural rainfall conditions. Transpiration from the 41st to the 60th day after transplanting was the highest showing about 50% of total transpiration of whole cultivation period. As the result, soil moisture condition in rhizospere of field was kept insufficiently during the above period. Transpiration by the plant was so remarkably affected by the meteorological environment that the transpiration on rain-cloudy day was one third of that on clear day at middle stage of the growth. Maximum transpiration in a clear day was obtained from 14:00 to 16:00 at the 58th day after transplanting.

• The Korean Journal of Food And Nutrition
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• v.9 no.3
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• pp.275-280
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• 1996

For the selection of powerful antagonistic bacterium for biological control of Ewinia sp. causing vegetable soft rot, two excellent strains (54, 565) were selected from 1, 196 strains of bacteria which were isolated from rhizospere in vegetable root rot suppressive soil. Selected 2 strains were identified to be a species to Pseudomonas fluorescens S4 and pseudomonas fluorescens S65 (PS65). The highest of inhibitory activity was produced in 523 synthetic broth medium at pH 7.0 and 25t during 3 ethyl-Al-folpet, and the antibiotics such as vancomycin, perucillin and lincomycin, only PS4 was resistant to erythromycin.

• Mycobiology
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• v.32 no.1
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• pp.35-41
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• 2004

A total of 374 Pythium isolates were isolated and identified from the rhizosphere soils of maize plants grown in 100 different agricultural fields in nine provinces at El-Minia Governorate, Egypt. Five Pythium spp. of P. deliense, P. graminicola, P. irregulare, P. oligandrum and P. splendens were obtained P. deliense and P. oligandrum were predominant in all of the locations with 48.1% and 41.4% of total counts, respectively. P. graminicola, P. irregulare and P. splendens were not isolated in 4, 2 and 4 provinces out of 9 provinces with 5.3%, 3.5%, and 1.6% of isolation percentage from total counts, respectively. Number of Pythium isolates in each were 34, 31, 34, 33, 34, 96, 37, 37 and 38 out of 374, for locations of El-Edwa, Maghagha, Beni-Mazar, Matai, Samalout, El-Minia city, Abou-Querquas, Mallawi and Der Mawas, respectively. Pre- and post-emergence pathogenicity tests indicated that only P. deliense was highly pathogenic to germinating grains and seedlings of maize whereas P. oligandrum was non-pathogenic.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.6
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• pp.522-527
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• 2004

Barley growing in paddy fields often suffers from wet-injury due to oxygen deficiency in rhizospere caused by excessive water in the soil. This study was conducted to investigate responsiveness of growth, development and anaerobic glycolysis enzymes to acute hypoxia in barley seedlings. Barley seedlings at the third leaf stage were subjected to hypoxia (1 ppm dissolved oxygen) by sparging the culture solution with nitrogen gas for up to seven days. Length and fresh weights of the shoot and root were affected little by hypoxia for up to 5 days. But root dry weight was slightly decreased by hypoxia for 7 days. In the root, alcohol dehydrogenase and lactate dehydrogenase activities increased drastically under hypoxia, reaching at their maximum levels in 3 to 5 days of hypoxia and decreasing slightly thereafter. However, the activities of both enzymes changed little in the shoot. Increases of their activities in the root were contributed by all the isozymes found in barley. These results suggest that barley seedlings first adapt to hypoxia by rapidly activating fermentative glycolysis to stabilize cellular pH and to increase energy production for the following morphological adaptative changes.