• Korean Journal Plant Pathology
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• v.12 no.3
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• pp.291-296
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• 1996

옥수수 유묘접종시 깜부기병이 가장 잘 발병하는 조건은 4엽기 옥수수묘를 10\ulcorner~10\ulcorner/ml 농도의 소생자 현탁액으로 경엽살포한 후 28~3$0^{\circ}C$의 습실상에서 24시간 둔 후 꺼내어 온실에 두었을 때였다. 유묘의 엽기가 이보다 어리거나 접종원 농도가 이보다 높을 때, 혹은 습실상내 처리기간이 길어지면 접종후 유묘의 이른 고사를 초래하였다. 또한 습실상의 온도가 낮아질수록 깜부기병의 발병정도도 감소하였다. 깜부기병의 발생은 소생자 현탁액의 경엽살포 및 줄기주사접종에 의해서는 가능하였지만 토양관주에 의해서는 발병하지 않았다. 소생자 현탁액은 별도의 영양원의 첨가 없이도 발병을 잘 유도하였다. 동포자 현탁액을 직접 경엽살포하거나 줄기주사접종하여도 발병하였으나 소생자 현탁액접종에 비하여 발병정도가 현저히 낮았다.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2000.10a
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• pp.15.1-15
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• 2000

• Horticultural Science & Technology
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• v.32 no.6
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• pp.803-811
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• 2014

This study was carried out to investigate the effect of relative humidity (70, 80, 90, and 95%) and to examine the interrelationship of temperature (15, 20, and $25^{\circ}C$) and relative humidity (60, 70, 80, and 90%) in the greenhouse on growth and occurrence of white rust in chrysanthemum 'Baekma'. The developmental stages of white rust were monitored from the initial occurrence to sporidium formation in teliospores. When the relative humidity of greenhouse was adjusted to 90% or more for 40 days, the occurrence rate of white rust, the number of infected leaves, and the number of symptoms per leaf were more than 97%, 10, and 55, respectively. However, in the treatment with 70% relative humidity, the occurrence rate of white rust dropped to 30% and only two spots of symptoms were observed with only 1 or 2 infected leaves per plant. The growth of cut flowers, such as fresh weight and leaf number, was the highest in 70% relative humidity. In the 90% relative humidity treatment, the first symptom of white spot appeared at 6 days after planting in chrysanthemum infected with white rust (stage 1), and then after one day, teliospores came out through the epidermal tissue of leaf (stage 2). The telium was formed with increasing teliospores after 1 to 2 days (stage 3), and then the promycelia developed from teliospores (stage 4). After a lapse of 4 to 5 days, sporidia formed on promycelia (stage 5). Regardless of relative humidity, white rust did not occur at all in treatments at $25^{\circ}C$. In treatments at $20^{\circ}C$, the number of sporidia was high regardless of relative humidity, but white rust did not occur in 60% and 70% relative humidity. As the relative humidity was higher, the number of sporidia and occurrence rate of white rust greatly increased, but the occurrence rate of white rust decreased to less than 14% in 60% and 70% relative humidity in treatment at $15^{\circ}C$.

• Korean Journal Plant Pathology
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• v.12 no.2
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• pp.147-149
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• 1996

Ustilago maydis의 소생자는 물한천배지에서 접종후 8시간 후에 98% 이상 발아하였다. PDA를 포함한 기타 영야배지에서의 발아율도 이와 비슷하였다. 소생자 발아에 가장 적당한 온도는 3$0^{\circ}C$였으며 $25^{\circ}C$나 35$^{\circ}C$순으로 양호하였으나 2$0^{\circ}C$나 그 이하의 저온에서는 발아율이 급격히 떨어졌다. 소생자는 pH 5~9의 범위에서 80%이상 발아하였으나 최적 pH는 6~7이었다. 광조사는 소생자 발아에 큰 영향을 미치지 못하였다. 소생자는 자유수분(RH 100%)하에서 24시간 후 81%가 발아하였으나 상대습도가 93%나 그 이하에서는 발아율이 19~34%였다. 이 실험결과는 소생자 발아에 가장 큰 영향을 미치는 환경요인은 온도와 습도였으며 우리나라 기후조건에서 소생자는 7~8월의 한여름철 장마기간 동안 왕성하게 발아할 수 있음을 뜻하고 있다.

• The Plant Pathology Journal
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• v.31 no.2
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• pp.97-107
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• 2015

Alteration of genetic make-up of the isolates and mono-sporidial strains of Tilletia indica causing Karnal bunt (KB) disease in wheat was analyzed using DNA markers and SDS-PAGE. The generation of new variation with different growth characteristics is not a generalized feature and is not only dependant on the original genetic make up of the base isolate/monosporidial strains but also on interaction with host. Host determinant(s) plays a significant role in the generation of variability and the effect is much pronounced in monosporidial strains with narrow genetic base as compared to broad genetic base. The most plausible explanation of genetic variation in presence of host determinant(s) are the recombination of genetic material from two different mycelial/sporidia through sexual mating as well as through parasexual means. The morphological and development dependent variability further suggests that the variation in T. indica strains predominantly derived through the genetic rearrangements.