• Mycobiology
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• v.31 no.3
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• pp.173-178
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• 2003

India has maximum genetic materials in early cauliflower, which grow in subtropical conditions. Different disease parameters like linear growth, maximum growth rate per day, AUDPC, apparent infection rate and percent diseased area were calculated in artificially inoculated plants. Apparent infection rate is not co-related with the black rot disease incidence and should never be considered during characterization of disease resistance and varietal screening. Based on the above disease parameters Kunwari-18, Phool Gobhi Kunwari, Kataki-7 and BT-10-2 were selected as moderately resistance to black rot in early cauliflower. These lines can be used for black rot prone area and also for black rot disease improvement programme. Considering the qualitative and quantitative parameters, slow rotting resistance cauliflower lines are selected as such for cultivation and would be best suited in integrated disease programme.

• Research in Plant Disease
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• v.15 no.1
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• pp.36-40
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• 2009

This research was accomplished to screen the cultivar which is suitable in organic cultivation of the broccoli having good horticultural characteristics and the resistance to black rot. Thirteen cultivars of the broccoli were planted at Gangwon alpine areas of Pyeongchang county and Gangneung city and investigated the horticultural characteristics in 2006. Everybro, Tamsuerun, Nockjae, and Pilgrim had good horticultural characteristics in all two experimental fields. The resistance and susceptible reactions regarding the black rot of broccoli cultivars were different from according to two fields. This result means that physiological race of black rot pathogen distribute in Gangwon alpine areas. Everybro and Nockguck were resistance to black rot in all two experimental fields. Also these two cultivars had good horticultural characteristics. We recommend that Everybro and Nockguck will be suitable in organic cultivation.

• The Plant Pathology Journal
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• v.31 no.2
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• pp.181-185
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• 2015

This study aimed to evaluate six cauliflower genotypes regarding their resistance to black rot and their production performance. To do so, it was conducted two field experiments in Ipameri, $Goi\acute{a}s$, Brazil, in 2012 and 2013. It was used a randomized block design, with four replications (total of 24 plots). Each plot consisted of three planting lines 2.5 m long (six plants/line), spaced 1.0 m apart, for a total area of $7.5m^2$. Evaluations of black rot severity were performed at 45 days after transplanting, this is, 75 days after sowing (DAS), and yield evaluations at 90 to 105 DAS. The Verona 184 genotype was the most resistant to black rot, showing 1.87 and 2.25% of leaf area covered by black rot symptom (LACBRS) in 2012 and 2013. However, it was not among the most productive materials. The yield of the genotypes varied between 15.14 and 25.83 t/ha in both years, Lisvera F1 (21.78 and 24.60 t/ha) and Cindy (19.95 and 23.56 t/ha) being the most productive. However, Lisvera F1 showed 6.37 and 9.37% of LACBRS and Cindy showed 14.25 and 14.87% of LACBRS in 2012 and 2013, being both considered as tolerant to black rot.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.2
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• pp.118-125
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• 1978

To find out highly resistant gene source to black rot fungus in sweetpotato varieties, a screening test was carried out with inoculated tubers and sprouts in 1976 and 1977. Fifteen varieties out of 165 and 54 varieties out of 161 were highly resistant to black rot in the tuber and sprout tests. respectively. The sprout test showed bigger variation from year to year compared to tuber test. Varieties highly resistant to black rot in both tuber and sprout tests were Suweon # 59, #81, #90, Norin #17, #23. Chilship-il cho, Sachun Jong #36, Hamkao, and Kandee.

• Research in Plant Disease
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• v.29 no.2
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• pp.158-167
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• 2023

Black rot of Chinese cabbage caused by Xanthomonas campestris pv. campestris (Xcc) is one of the most severe diseases in crop cultivation. To define the resistance characteristics of Chinese cabbage to Xcc, we tested the virulence of eight Xcc isolates in four susceptible cultivars of Chinese cabbage. The isolates of Xcc showed different the virulence on the cultivars. On the other hand, we selected 22 resistant or moderately resistant cultivars of Chinese cabbage to Xcc and tested the occurrence of black rot on the cultivars caused by the isolates of Xcc. Mean disease severity of black rot on the Chinese cabbage caused by each isolate was also positively correlated with the virulence of Xcc isolates. Furthermore, the development of black rot in each cultivar increased according to virulence of Xcc isolates. The number of resistant cultivars of Chinese cabbage to eight isolates of Xcc decreased according to the virulence increase of bacteria. Taken together, these results suggest that resistance of Chinese cabbage cultivars to Xcc is likely affected by the virulence of Xcc isolates, but not result from race differentiation.

• Korean journal of applied entomology
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• v.4
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• pp.25-28
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• 1965

The study was carried on a new disease of rice seedling which named 'Black rot of rice seedling'. None of papers on this disease was reported recently. The symptom of this disease was quite different from other seedling rot of rice plant. Submerged mycelial growth in water was black colored and it was surrounded whole surface of seed. Soil on which diseased seedlings were placed was black colored by this disease and the seedlings, finally stopped to grow within 3 em in height, and appeared with black rot symptom. Sporulation of the pathogen does not occurred under both of natural and artificial conditions. The mycelium appeared in dark color and with distinguished septation under the microscope. With those results it is easily recognized that the pathogen does not belong to those which causal organism:; of other seedling rot of rice plant like as Phycomycetes or Fusarium species. The study should be continued on identification of the causal organism. Favorable environments for the disease did not differ from other seedling rot of rice plant, and varietal resistance also did not significantly differ among the varieties used in this experiment. Dissemination of the disease was carried out not by planted seeds but by infected soil.

• The Plant Pathology Journal
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• v.30 no.3
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• pp.323-329
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• 2014

Two cultivars Buram-3-ho (susceptible) and CR-Hagwang (moderate resistant) of kimchi cabbage seedlings showed differential defense responses to anthracnose (Colletotrichum higginsianum), black spot (Alternaria brassicicola) and black rot (Xanthomonas campestris pv. campestris, Xcc) diseases in our previous study. Defense-related hormones salicylic acid (SA), jasmonic acid (JA) and ethylene led to different transcriptional regulation of pathogenesis-related (PR) gene expression in both cultivars. In this study, exogenous application of SA suppressed basal defenses to C. higginsianum in the 1st leaves of the susceptible cultivar and cultivar resistance of the 2nd leaves of the resistant cultivar. SA also enhanced susceptibility of the susceptible cultivar to A. brassicicola. By contrast, SA elevated disease resistance to Xcc in the resistant cultivar, but not in the susceptible cultivar. Methyl jasmonate (MJ) treatment did not affect the disease resistance to C. higginsianum and Xcc in either cultivar, but it compromised the disease resistance to A. brassicicola in the resistant cultivar. Treatment with 1-aminocyclopropane-1-carboxylic acid (ACC) ethylene precursor did not change resistance of the either cultivar to C. higginsianum and Xcc. Effect of ACC pretreatment on the resistance to A. brassicicola was not distinguished between susceptible and resistant cultivars, because cultivar resistance of the resistant cultivar was lost by prolonged moist dark conditions. Taken together, exogenously applied SA, JA and ethylene altered defense signaling crosstalk to three diseases of anthracnose, black spot and black rot in a cultivar-dependent manner.

• Research in Plant Disease
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• v.19 no.2
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• pp.95-101
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• 2013

Black rot caused by Xanthomonas campestris pv. campestris (Xcc) is one of the most serious diseases of crucifers world-wide. To establish the efficient screening method for resistant cabbage to Xcc, different inoculation methods, inoculation positions, growth stages of seedlings, and incubation temperatures after inoculation were investigated with the seven cabbage cultivars showing different resistance degrees to the pathogen. Clipping with mouse-tooth forceps was better inoculation method than piercing with 18 pins or cutting with scissors to distinguish the level of resistance and susceptibility. In inoculation using mouth-tooth forceps, clipping the edges of the leaves near veins is more effective than injuring the veins of the leaves directly. In addition, the inoculated plants kept at $22^{\circ}C$ showed more clear resistant and susceptible responses than those kept at 26 or $30^{\circ}C$. On the basis of the results, we suggest that an efficient screening method for resistance of cabbage cultivars to black rot is to clip the edges of the leaves near veins of the four-week-old seedlings with mouth-tooth forceps dipped in a suspension of Xcc at a concentration of $7{\times}10^7$ cfu/ml and incubate the inoculated plants in a growth room at $22^{\circ}C$ with 12-hr light a day.

• The Plant Pathology Journal
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• v.38 no.4
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• pp.272-286
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• 2022

Black root rot (BRR) caused by Lasiodiplodia theobromae is an alarming disease of mulberry that causes tremendous economic losses to sericulture farmers in India and China. Successful control of this disease can be attained by screening germplasm and identifying resistant sources. Seventy four diseased root samples were collected from farmer's fields belonging to four major mulberry growing states of South India. Based on morpho-cultural and scanning electron microscopy studies, 57 fungal isolates were characterized and identified as L. theobromae. Phylogenetic analysis of concatenated internal transcribed spacer and β-tubulin sequences revealed variation of the representative 20 isolates of L. theobromae. Following the root dip method of inoculation, pathogenicity studies on susceptible mulberry genotypes (Victory-1 and Thailand male) recognized the virulent isolate MRR-142. Accordingly, MRR-142 isolate was used to evaluate resistance on a set of 45 diverse mulberry accessions. In the repeated experiments, the mulberry accession ME-0168 which is an Indonesian origin belonging to Morus latifolia was found to be highly resistant consistently against BRR. Eight accessions (G2, ME-0006, ME-0011, ME-0093, MI-0006, MI-0291, MI-0489, and MI-0501) were found to be resistant. These promising resistant resources may be exploited in mulberry breeding for developing BRR resistant varieties and to develop mapping populations which successively helps in the identification of molecular markers associated with BRR.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.4 no.1
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• pp.103-108
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• 1968

Resistance to various diseases of Korean native varieties were investigated in field. The results obtained are summarized as follows: 1) The varieties Ubangtchio and Osib-eubthio were moderately resistant to black shank, but Suantchio, Usultchio and Gwangtchio were slightly resistant. Dixie Bright 101, $H_2$ and Bright Yellow 4 were more resistant to black shank than any of the Korean native varieties. 2) Mokgitchio, Ubangtchio and Osib-eubtchio were moderately resistant to black root rot, but Useultchio Suantchio and Hoetchio were susceptible than Others. 3) Muktchio, Hoetchio and Ubangtchio were slightly resistant to wild fire. 4) Osib-ebthio was highly resistant to brown spot, but Ubangtchio, Hyangtchio and Mokgitchio were moderately resistant and Useultchio was susceptible to brown spot, but it was resistant than Bright ellow 4 or Bernhart 1000-1. 5) Hyangtchio was slightly resistant to CMV-Y. According to these results, except Virus disease, Ubangtchio was resistant to all of the above mentioned diseases. Osib-eubtchio, Hoetchio, Hyangtchio and Suantchio showed proferable disease resistant and these might be well utilized as breeding materials.