• Journal of Microbiology and Biotechnology
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• 제20권1호
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• pp.208-216
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• 2010

Fusarium verticillioides is an important pathogen of maize, being responsible for ear rots, stalk rots, and seedling blight worldwide. During the past decade, F. verticillioides has caused several severe epidemics of maize seedling blight in many areas of China, which lead to significant losses. In order to understand the molecular mechanisms regulating fungal development and pathogenicity in this pathogen, we isolated and characterized the gene fpk1 (GenBank Accession No. EF405959) encoding a homolog of the cAMP-dependent protein kinase catalytic subunit, which included a 1,854-bp DNA sequence from ATG to TAA, with a 1,680-bp coding region, and three introns (lengths: 66 bp, 54 bp, and 54 bp), and the predicated protein precursor had 559 aa. The mutant ${\Delta}fpk1$, which was disrupted of the fpkl gene, showed reduced vegetative growth, fewer and shorter aerial mycelia, strongly impaired conidiation, and reduced spore germination rate. After germinating, the fresh hypha was stubby and lacking of branch. When inoculated in susceptible maize varieties, the infection of the mutant ${\Delta}fpk1$ was delayed and the infection efficiency was reduced compared with that of the wild-type strain. AU this indicated that gene fpk1 participated in hyphal growth, conidiophore production, spore germination, and virulence in F. verticillioides.

• 한국균학회지
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• 제13권1호
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• pp.41-47
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• 1985

18종(種)의 식물질(植物質)을 토양(土壤)에 첨가(添加)하여 개량(改良)한 토양(土壤)에 인삼근부병원(人蔘根腐病原)에 하나인 Fusarium solani의 후막포수(厚膜胞數)$5{\times}10^3\;Cells/g\;soil)$를 접종(接種)하고 여기에 지표(指標)가 되는 식물(植物) 로 완두(Pisium sativa L.)를 심어 이병성(罹病性) 정도(程度)에 의하여 개량효과를(改良效果) 조사하고 또한 개량물질(改良物質)의 처리(處理) 전(前)과 후(後)의 토양내(土壤內)의 미생물분포(微生物分布)의 변동(變動)을 비교(比較)하였다. 식물질(植物質)로 개량(改良)한 토양처리구(土壤處理區)에서 분쇄밀처리구에서는 대조구(對照區) 이상으로 이병성( 罹病性)이 높았고, 다음이 고구마 줄기, 배추, 인삼잎 및 콩깍지의 순이였다. 반면 마늘 뿌리를 처리한 토양에서는 이병률(罹病率)이 가장 낮아 효과적(效果的) 인 개량물질(改良物質)이었고, 다음에 파, 양배추, 들깨대, 밀짚, 보리짚등에서도 이병률(罹病率)이 감소(減少)하였다. 총균수(總菌數)는 파, 콩, 분쇄밀, 옥수수대, 배추등에서 다수(多數)하였고, 반면 밀짚, 마늘뿌리, 양배추, 보리짚 등의 처리구에서는 감소하였다. 세균수(細菌數)는 콩, 양배추, 무우줄기, 파, 분쇄밀처리구에서는 증가(增加)되었으나 보리, 담배뿌리, 인삼대, 밀짚등에서는 감소(減少)하는 경향을 나타냈다. 방선균(放線菌)의 분포(分布)는 콩처리구에서만 증가(增加)하였으나 기타는 대조구(對照區) 보다 감소(減少)하고 담배뿌리와 마늘대에서는 그 수(數)가 감소(減少)되었다. Fusarium spp의 분포수(分布數)는 배추, 파, 무우줄기, 분쇄밀, 고구마줄기 등의 처리구에서는 증가(增加)하고 반대로 밀짚, 인삼잎, 양배추등의 처리구는 대조구(對照區) 보다 감소(減少)하였다.

• Journal of Animal Science and Technology
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• 제60권2호
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• pp.1.1-1.6
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• 2018

Background: Maize fodder is being used as staple feed for livestock but it lacks protein and essential amino acids; lysine and tryptophan. Intercropping maize with leguminous soybean crop is promising technique under limited land resources of South Korea but it can only give considerable advantages when adequate distance is provided between corn and soybean rows. Main aim of present study was to find-out adequate distance between corn and soybean seeding rows for optimum growth, yield and nutritive value of intercropped forage. Methods: Different interrow distances between corn and soybean were evaluated under four treatments, viz. 1) Corn sole as positive control treatment 2) Zero cm between corn and soybean (control); 2) Five cm between corn and soybean; 3) 10 cm between corn and soybean, with three replicates under randomized block design. Results: Findings depicted that height and number of corn stalks and ears were similar (P > 0.05) among different treatments. Numerically average corn ear height was decreased at zero cm distance. Dry matter percentage in all components; corn stalk, corn ear and soybean was also found not different (P > 0.05) but dry matter yield in component of corn ear was lower (P < 0.05) at zero cm distance as compared to that of 5 and 10 cm interrow distances. In case of nutritive value, total digestible nutrient yield in intercropped corn was also found lower (P < 0.05) at zero cm distance than that of 5 and 10 cm interrow distances between corn and soybean seeding rows. Substantial decrease in dry matter yield of maize ear at zero cm distance might be attributed to factor of closed interrow spacing which made interplant competition more intensified for light interception, necessary for photosynthetic activity. Lower dry matter yield in ear also reduced total digestible nutrients in intercropped maize because it was determining factor in calculation of digestible nutrients. The optimum yield and nutritive value of forage at wider interrow distance i.e. 5 cm between corn and soybean might be due to adequate interseed distance. Conclusion: Conclusively, pattern of corn and soybean seeding in rows at 5 cm distance was found suitable which provided adequate interrow distance to maintain enough mutual cooperation and decreased competition between both species for optimum production performance and nutritive value of intercropped forage.

• The Plant Pathology Journal
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• 제24권1호
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• pp.1-7
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• 2008

Fusarium verticillioides (teleomorph Gibberella moniliformis) is associated with maize worldwide causing ear rot and stalk rot, and produces fumonisins, a group of mycotoxins detrimental to humans and animals. While research tools are available, our understanding of the molecular mechanisms associated with fungal virulence and fumonisin biosynthesis in F. verticillioides is still limited. One of the restraints that hampers F. verticillioides gene characterization is the fact that homologous recombination (HR) frequency is very low (<2%). Screening for a true gene knock-out mutant is a laborious process due to a high number of ectopic integrations. In this study, we generated a F. verticillioides mutant (SF41) deleted for FvKU70, a gene directly responsible for non-homologous end-joining mechanism, with the aim of improving HR frequency. Here, we demonstrate that FvKU70 deletion does not impact key Fverticillioides phenotypes, e.g., development, secondary metabolism, and virulence, while dramatically improving HR frequency. Significantly, we also confirmed that a high percentage (>85%) of the HR mutant strains harbor a desired mutation with no additional copy of the mutant allele inserted in the genome. We conclude that SF41 is suitable for use as a type strain when performing high-throughput gene function studies in F. verticillioides.

• The Plant Pathology Journal
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• 제35권4호
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• pp.301-312
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• 2019

Sorghum is the fifth most important cereal worldwide, spreading from Africa throughout the world. It is particularly important in the semi-arid tropics due to its drought tolerance, and when cultivated in Southeast Asia commonly occurs as a second crop during the dry season. We recovered Fusarium from sorghum in Thailand and found F. proliferatum, F. thapsinum and F. verticillioides most frequently, and intermittent isolates of F. sacchari and F. beomiforme. The relatively high frequencies of F. proliferatum and F. verticillioides, suggest mycotoxin contamination, particularly fumonisins and moniliformin, should be evaluated. Genetic variation within the three commonly recovered species was characterized with vegetative compatibility, mating type, Amplified Fragment Length Polymorphisms (AFLPs), and female fertility. Effective population number ($N_e$) was highest for F. verticillioides and lowest for F. thapsinum with values based on mating type allele frequencies higher than those based on female fertility. Based on AFLP genetic variation, the F. thapsinum populations were the most closely related, the F. verticillioides populations were the most distantly related, and the F. proliferatum populations were in an intermediate position. The genetic variation observed could result if F. thapsinum is introduced primarily with seed, while F. proliferatum and F. verticillioides could arrive with seed or be carried over from previous crops, e.g., rice or maize, which sorghum is following. Confirmation of species transmission patterns is needed to understand the agricultural systems in which sorghum is grown in Southeast Asia, which are quite different from the systems found in Africa, Australia, India and the Americas.

• 한국초지조사료학회지
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• 제5권1호
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• pp.45-52
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• 1985

本試驗은 옥수수 및 Sorghum類에 싫어서 形態的特性과 環境溫度가 Fructosan Mono- 및 Disaccharose의 合成, 移動 및 蓄績形態와 NEL價値이 미치는 影響을 究明코저 옥수수의 Blizzard와 Sorghum의 Sioux 및 Pioneer931을 供試品種으로 하여 圃場 및 Phytotron試驗으로 實施하였다. Phytotron의 晝/夜間 室內溫度는 30/25, 25/20, 28/18및 18/8$^{\circ}C$로 하였으며 日照는 30.000~35.000 Lux로 13時間 照謝하였다. 1978~’81年까지 얻어진 結果를 要約하면 다음과 같다. 1. 옥수수 및 Sorghum類의 non-structural carbohydrate는 主로 Mono- 및 nisaccharose形態로 蓄績된다. Mono- 및 Disaccharose의 蓄績은 幼穗가 分化된以後 本格的으로 이루어져 乳熟期初期에 各各 옥수수 27.8~29.1 % 및 Sorghum類 16.8-20.4%로 最高濃度水準에 달한다. 2 Fructosan含量은 옥수수와 수수 各作物 共히 1.5~2.5%內外로서 全生育期間을 通해 큰 變化가 없다. 3. Mono- 및 nisaccharose는 主로 줄기部位에 蓄績되나 出糖期以後 穀實이 形成됨에 따라 이들 T財C의 大部分은 이삭部位로 移動되어 Starch 形態로 貯藏된다. Starch의 合成 및 蓄績은 Mono- 및 Disaccharose의 減少와 灰比例 한다. 4. 옥수수 및 Sorghum의 同化能力은 溫度가 上昇됨에 따라 增大되나 溫度 30$^{\circ}C$以上의 高溫下에서는 植物體內의 Mono- 및 Disaccharose蓄績이 적게 일어난다. 한편 溫度 18/8$^{\circ}C$以下의 低溫에서는 合成된 Saccharose가 移動되지 못하고 줄기 및 葉에 과다 蓄績되어 葉의 同化能力이 減少되고 物質生産이 中止된다. 5 NEL 및 Starch value는 non- structural carbohydrate의 合成 및 蓄續形態에 따라 影響을 받는다. 植物體內의 NEL 蓄績은 Mono- 및 Disaccharose의 蓄積이 本格的으로 進行되는 幼穗分化期以後부터 서서히 增加하여 完熟初期에 各各 옥수수 6.6~6.9MJ/kg 및 Sorghum類 5.8~6.0MJ- NEL/kg으로 가장 높은 水準을 나타낸다.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2014년도 추계학술대회 및 정기총회
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• pp.15-15
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• 2014

Fusarium graminearum (teleomorph Gibberella zeae) is an important plant pathogen that causes head blight of major cereal crops such as wheat, barley, and rice, as well as causing ear and stalk rot on maize worldwide. Plant diseases caused by this fungus lead to severe yield losses and accumulation of harmful mycotoxins in infected cereals [1]. Fungi utilize spore production as a mean to rapidly avoid unfavorable environmental conditions and to amplify their population. Spores are produced sexually and asexually and their production is precisely controlled. Upstream developmental activators consist of fluffy genes have been known to orchestrate early induction of condiogenesis in a model filamentous fungus Aspergillus nidulans. To understand the molecular mechanisms underlying conidiogenesis in F. graminearum, we characterized functions of the F. graminearum fluffy gene homologs [2]. We found that FlbD is conserved regulatory function for conidiogenesis in both A. nidulans and F. graminearum among five fluffy gene homologs. flbD deletion abolished conidia and perithecia production, suggesting that FlbD have global roles in hyphal differentiation processes in F. graminearum. We further identified and functionally characterized the ortholog of AbaA, which is involved in differentiation from vegetative hyphae to conidia and known to be absent in F. graminearum [3]. Deletion of abaA did not affect vegetative growth, sexual development, or virulence, but conidium production was completely abolished and thin hyphae grew from abnormally shaped phialides in abaA deletion mutants. Overexpression of abaA resulted in pleiotropic defects such as impaired sexual and asexual development, retarded conidium germination, and reduced trichothecene production. AbaA localized to the nuclei of phialides and terminal cells of mature conidia. Successful interspecies complementation using A. nidulans AbaA and the conserved AbaA-WetA pathway demonstrated that the molecular mechanisms responsible for AbaA activity are conserved in F. graminearum as they are in A. nidulans. F. graminearum ortholog of Aspergillus nidulans wetA has been shown to be involved in conidiogenesis and conidium maturation [4]. Deletion of F. graminearum wetA did not alter mycelial growth, sexual development, or virulence, but the wetA deletion mutants produced longer conidia with fewer septa, and the conidia were sensitive to acute stresses, such as oxidative stress and heat stress. Furthermore, the survival rate of aged conidia from the F. graminearum wetA deletion mutants was reduced. The wetA deletion resulted in vigorous generation of single-celled conidia through autophagy-dependent microcycle conidiation, indicating that WetA functions to maintain conidia dormancy by suppressing microcycle conidiation in F. graminearum. In A. nidulans, FlbB physically interacts with FlbD and FlbE, and the resulting FlbB/FlbE and FlbB/FlbD complexes induce the expression of flbD and brlA, respectively. BrlA is an activator of the AbaA-WetA pathway. AbaA and WetA are required for phialide formation and conidia maturation, respectively [5]. In F. graminearum, the AbaA-WetA pathway is similar to that of A. nidulans, except a brlA ortholog does not exist. Amongst the fluffy genes, only fgflbD has a conserved role for regulation of the AbaA-WetA pathway.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.84-84
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• 2022

The limit of crop cultivation is moving northward due to the temperature rise by climate change. There is a problem with crop growth if early sowing is performed at a time when the temperature is low. It is difficult to secure crop productivity and cultivation stability due to the low temperature and short cultivation period. Therefore, this study was conducted to analyze the change in growth characteristics and yield of corn for grain when early sowing is performed in central region of South Korea. This experiment was conducted at experimental field of Suwon in 2021. Three varieties of corn for grain such as Kwangpyeongok, Sinhwangok, and Hwangdaok were sown at intervals of 5 days from 20 March to 15 April. The planting density at this time was sown with a row interval of 70 cm and a plant interval of 25 cm. Nitrogen, phosphoric acid, and potassium fertilizers were applied at 17.4 kg, 3.0 kg, and 6.9 kg per 10a, respectively. Phosphoric acid and potassium fertilizers were all applied before sowing and nitrogen fertilizer was applied 50% before sowing and 50% in the fifth leaf period. The corn growth characteristics and yield components were investigated. The seedling establishment rate by sowing date was in the range of 68.5~88.5%, and it showed a difference depending on the variety. The range of days from sowing to tassel and silk emergence by sowing date was 79.9~98.4 and 81.0~98.9 days, respectively. As the sowing date was delayed, the days from sowing to tassel and silk emergence decreased. The growth characteristics and yield of corn by sowing date are as follows. Plant height was the highest at 241.3 cm at the sowing on 25 March, and Stalk diameter was the thickest at 25.6 mm at the sowing on 31 March. The fresh weight per plant was the highest at 728 g at the sowing on 25 March, and the dry weight per plant was the highest at 185 g at the sowing on 31 March. Corn growth characteristics did not show a certain trend depending on the sowing date, and corn growth was more vigorous at the sowing on March 25 and 31 than the others. In the case of ear weight, it was the heaviest with 344 g at the sowing on 25 March, and filled ear length ratio showed a tendency to decrease as the sowing time was delayed. The weight of 100 grains and grain yield per 10a of maize were the highest at 36.0g and 878.7kg/10a, respectively at the sowing on 25 March. Although the growth and yield of corn for grain were good during early sowing in the central region of South Korea, it is necessary to investigate the limit temperature for early sowing of corn by examining the annual variation according to weather conditions.

• 농업과학연구
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• 제15권2호
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• pp.123-131
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• 1988

형태적(形態的)으로 상이(相異)한 다종다얼성(多種多蘖性)인 특성(特性)인 형매교배(兄妹交配)된 IK 교잡종(交雜種)과 무얼성(無蘖性)인 진주옥 교잡종(交雜種)을 공시(供試)하여 청예수량(靑刈收量), 종실수량(種實收量) 및 이와 관련(關聯)된 형질(形質)을 비교(比較)하고자 IK와 진주옥의 파종비율(播種比率)을 1 : 1, 1 : 2, 1 : 3, 2 : 1, 3 : 1로 혼파(混播)한 것과 IK와 진주옥을 각각(各各) 단작(單作)하여 얻어진 결과(結果)를 요약(要約)하면 다음과 같다. 1. 공시(供試)된 품종(品種) 모두가 단작(單作)보다 혼작(混作)에서 초장(草長)이 큰 경향(傾向)이었고 진주옥의파종비율(播種比率)을 증가(增價)할수록 IK의 생육(生育)은 저조(低調)한것으로 나타났다. 2. 출현(出現) 후(後) 40 일경(日頃)까지 모든 처리구(處理區)에서 IK의 분얼수(分蘖數)는 증가(增加)하였는데 IK의 파종비율(播種比率)이 많을수록 분얼수(分蘖數)의 증가(增加)가 뚜렷하였다. 3. IK 단작(單作)의 10 a당(當) 청예수량(靑刈收量)은 출사기(出絲期)에서 8,096kg이었고, 호숙기(糊熟期)서는 6,677kg으로 가장 많았는데 이는 진주옥 단작(單作)에 비(比)해 각각(各各) 77%와 53%가 증가(增加)되었고 IK와 진주옥의 1 : 1 처리구(處理區)에서는 진주옥 단작(單作)보다 20%가 증가(增加)되었다. 4. 10 a당(當) 종실수량(種實收量)은 진주옥 단작(單作)에서 434kg이었고 IK 단작(單作)은 373kg이었는데 IK와 진주옥을 1 : 1과 1 : 3으로 혼파(混播)한 구(區)에서 IK단작(單作)의 종실수량(種實收量)보다 16%와 13%가 각각(各各) 증가(增價)되었다. 5. IK 도복(倒伏)은 단작(單作)에서 29.2%로 진주옥의 파종비율(播種比率)이 증가(增價)할수록 IK 도복(倒伏)이 증가경향(增加碩向)이었는데 IK와 진주옥을 1 : 1 혼파(混播)한 구(區)에서 IK의 도복율(倒伏率)이 10.9%로 크게 경감(輕減)되었다. 6. 진주옥의 파종비율(播種比率)이 많을수록 IK의 경직경(莖直俓)이 감소(減少)하였고 착수고(着穗高)는 IK의 파종비율(播種比率)이 많을수록 IK의 착수고(着穗高)가 낮아지는 경향(碩向)이었다. 흑조위축병(黑條萎縮病) 리병율(罹病率)은 두 품종(品穩) 모두 파종비율(播種比率)과는 관련(關係)없이 저항성(抵抗性) 품종(品種)임이 확인(確認)되었다.