2,396 research outputs found
(15(2):11-19)EFFECT OF ANTIBIOTIC FUNGICIDES FOR CONTROL OF RICE SEEDLING BLAST
No full text本試驗係欲明瞭，供試抗生素藥劑在本省環境下（亞熱帶）對稻熱病之防治效果及藥害之程度而舉行，其所得結果簡述如下：
1.本試驗行人工接種病原菌，使稻熱病發生並非自然發生者。
2.供試稻種為臺中65號（Japonica type）及矮脚尖（Indica type）兩種。前者發病猖獗，後者之發病極輕微，故藥劑之藥效僅能根據臺中65號之防治效果論之。
3.據臺中65之防治效果得知，處理間，撒佈藥劑與否，都呈極顯著，藥劑之間的差異，第一次試驗呈顯著，第二次試驗呈極顯著。
4.防治稻熱病之效果最優者為Kasumin可濕性粉劑，其次為Blaes乳劑。
5.Kasumin可濕性粉劑供用濃度（250-1,000）之間均無藥害之發生，反之葉色呈濃綠色，對稻苗之生育良好。Blaes如使用高濃度（250倍）時易引起藥害，故實際使用時之濃度不可高於1,000倍之稀釋液。
The effectiveness of antibiotics for control of rice seedling blast was evaluated in the nursery. Artificial inoculations were made to induce the occurrence of the disease. Since Ai-Chiao-Chien, one of the two varieties tested were only slightly infected, the results reported herein are based on the data obtained with Taichung 65. Application of Kasumin W. P. resulted in the best control of seedling blast, while Blaes E. C. gave considerable reduction of the disease. No phytotoxicity was noticed on leaves sprayed with Kasumin W. P. at three different concentrations tested. Leaves in Kasumin W. P. sprayed blocks showed greener in color as compared to those in check block. Blaes E. C., however, when applied at the rate of four grams per liter incited sever phytotoxicity on rice seedlings. It is, therefore, suggested that Blaes E. C. should not be applied at the concentration higher than one gramper liter
The Vitamin, Carbon And Nitrogen Nutrition Of Pircularia Oryzae Cav. Part II
No full textVitamin requirement for growth and sporulation of a certain isolates of Piricularia oryzae Cay. were determined. Of the vitamins studied, only biotin and thiamine were essential to the growth of the fungus. Other vitamins were found ineffective. The depend-ency of the fungus on biotin was greater than on thiamine. All isolates tested required exogenous biotin for mycelial growth. It was found that a majority of the isolates had a partial requirement for thiamine. No isolates exhibited an absolute requirement for thiamine. Both biotin and thiamine were absolutely essential for the sporulation of P. oryzae. No conidia were produced by any isolate in either biotin or thiamine free media. In the absence of thiamine, several isolates of the fungus were able to make fairly abundant mycelial growth, but failed to produce spores. The minimum concentration of biotin for the optimum mycelial growth of the fungal isolates was 0.5 ug/1, and of thiamine, 0.02 mg/i. Below these concentrations, the growth of the fungus was drastically reduced. No correlation was observed between pathogenicity and vitamin requirement of the fungus
(23(1):16-37)STUDIES ON THE PHYSIOLOGIC RACES OF RICE BLAST FUNGUS, PYRICULARIA ORYZAE CAV.
No full text本研究係為闡明本省稻熱病病原菌之生理分化、種類及其分佈狀況，以及本省育成稻品種、品系對本省主要稻熱病菌生理小種之抗病程度，以配台稻作抗稻熱病育種及稻品種推廣之依據。茲將三年來研究結果簡述如下：
鑑定稻熱病菌生理型所用之胞子浮懸液，每ml內之分生胞子濃度以100萬個左右圾妥當。民國59~61年之間，於奎洶各地區探集稻熱病菌計537菌株，經測定對16判別稻種之致病反應結果，可類別五個羣(Group P. I. T. K. N)，包括35種生理型，其中認為新出現者有14種生理型。而可歸入P羣者為roce43；I羣者有race 40, 41, 42, 49；T羣者有race 37, 38, 39, 44, 45, 46, 47, 48；N羣者有race 36。在此3年期間每年所出現之生理小種並不一致，在59年度獲219菌株可類別26種生理型，60年度獲152菌株可類別29種生理型，61年度獲166菌株可類別20種生理型。又35個生理小種中出現頻度最多者為race 30，佔供試菌株（537菌株）的14.7%，其次為race 40佔7.8%，再其次為race 35佔7.6%，最少者為race 21及49各僅1菌株而已。如果按各羣的出現頻度觀之，T群最多，佔56.0%，其次為I羣，佔26.1%，再次為K羣，佔7.6%，P羣亦佔7.5%，最少者為N羣，僅佔2.8%。
就地區分佈狀況觀之，宜蘭地區計21種生理型，其中以race40出現多，次為race 30，再次race 32；臺中地區計23種生理型，以race 30最多，次為race 35，再次為race 40，嘉義地區計24種生理型，以race 30最多，次為race 40；屏東地區計28種生理型，以race 30最多，次為race 37，再次為race 13；臺東地區計23種生理型，以race 30最多，次為race 35，再次為race 37；花蓮地區計17種生理型，以race 30最多，次為race 29。
在112稻品種中，對本省主要稻熱病菌生理小種之抗病力較強者有臺中秈試165號、臺中試183號、矮腳尖、白米粉、高雄選1號及臺中186號等六個品種，此等品種將來可作抗稻熱病育種的良好材料。
The purpose of this study was to clarify the specialization and distribution of the physiologic races in Taiwan in order to support the breeding program.
The results obtained from 1970 to 1972 were summarized as fellows:
The optimum concentration of spore suspension for inoculation in identification of races of blast fungus was at 106/m1.
From 1970 to 1972, 537 isolates were collected from several areas in Taiwan and were classified into 5 groups (P, I, T, K, N) by artificial inoculation. The isolates were tested with the 16 differential varieties including 35 physiologic races in which 14 races were newly appeared. The race 43 belongs to P group ; race 40, 41, 42, 49 belong to I group race 37, 38, 39, 44, 45, 46, 47, 48 belong to T group race 36 belongs to N group.
The frequency of races appearance were inconsistency during the past three years. In
1970, 219 isolates were evaluated and were classified into 26 races. In 1971, 29 races were identified from 152 isolates, and 20 races were classified from 166 isolates in 1972. Among the 35 races tested, the highest frequency of appearance was race 30, possessing 14.7 percent over 537 isolates. The race 40 (7.8%) was the next, then race 35 (7.6%) , race 21 and race 49 (0.18% each).
The frequency of group order were T group (56.0%); I group (26.1%); K group (7.6 %); P group (7.5%) and N group (2.8%).
There were 21 races distributed in Ilan area, in which race 40 was the most common one, then the race 30 and race 32. In Taichung area, 23 races were found. The major race were race 30 nextly were races 35 and 40. The major races in Chiayi area were races 30 and 40 where 24 races were included in this area. In Pingtung area, 28 races were found. The race 30 was predominant over there, nextly were race 37 and race 13. In Taitung area race 30 was predominant, then race 35 and race 37 with overall races of 23 races. There were 17 races distributed in Hualien area with major races of race 30 and race 29.
In the 112 rice varieties tested, only 6 of them, namely Taitung-shih 165, Taichung-shih 183, Aichueh-chien, Pai-rnifen, Kaohsiung-hsuan 1 and Taichung 186 were strongly resistant to Taiwan major races and can be used in the rice breeding program for developing resistant varieties to the blast disease
(6(3):41-46)EFFECT OF CERESAN-LIME ON THE CONTROL OF RICE BLAST DISEASE
No full text1. Ceresan石灰防治稻熱病之效果，較石灰波爾多液為佳，但距病原接種日期越久，效力越低。先撒佈藥劑而後酒水，共保護作用可達3天，石灰波爾多液則不及之。
2. 穗稻熱病之防治，兩種藥劑撒佈3次者共效果較2次者為高。
3. 撒佈Ceresan石灰者與對照區比較，其產量可減少20~40%之損失，石灰波爾多液為10~25%。
4. 當出穗前後撒佈Ceresan石灰，與對照區比較，對穗稽熱病之被害率可減少45~70%，石灰波爾多液者約20~65%。僅于出穗後撒佈一次者，其效果則不及前者。
5. 節稻熱病之防除，當出穗前後撒佈者較為有效。
6. 無論出穗前抑後僅撒佈Ceresan石灰一次者，與對照區比較，其產量均可減少10～13%之損失，石灰波爾多液則不及之。
This paper deals with the comparative studies on the effectiveness of Ceresan-lime (0.6% Ethyl Mercury Chloride, Hg. 0.25%) and Bordeaux mixture of 4-8 formula (4 g. of Copper sulphate, 8 g. of stone lime, and 1,000 cc of water) for the control of rice blast. According to laboratory and field trials which showed that Ceresan-lime dusting (30 kg per ha.) is more effective for controlling the disease than Bordeaux mixture (4000-5000 litre per ha.) spraying.
Leaf blast could be well controlled by three applications of Ceresan-lime before heading stage of rice. For the purpose of protecting the neck of ears and the node of culms become infested with the disease, then dusting should be held before and after heading stage
(24(3-4):23-31)A SURVEY ON THE PREVALENCE OF PANICLE BLAST OF THE LONG GRAIN INDICA TYPE RICE, WITH SPECIAL EMPHASIS ON THE PHYSIOLOGICAL RACES OF BLAST FUNGUS
No full text民國六十三年第二期作於臺南、嘉義、雲林及南投等四縣栽培之長粒型秈稻（嘉農秈8號及11號）異常發生穗稻熱病，嘉農秈8號之栽培面積1,702.0公頃中，受穗稻熱病為害者高達74.83%，而嘉農秈11號之栽培面積4,270.3公頃中，發生面積為28.95%，由此可知其嚴重性。此兩種稻品種發生穗稻熱病之特性，在被害穗之葉節部位受病原菌之侵害（所稱葉節稻熱病）頗普遍。
自被害稻穗分離所得菌株，經對16判別稻種測定結果，可類別為五羣(Groups)，包括21種不同生理小種(Races)，其中新出現之生理小種有五種之多。在21種生理小種中，屬於I羣者13種，T羣2種，K羣4種，N及A羣者各1種。侵害嘉農秈8號及嘉農秈11號之主要稻熱病菌生理型，前者為Race 55及51，後者為Race 51及31等。由此可知可侵害印度型稻之生理型頗多，今後對稻熱病之發生消長，吾人需特別提高警覺。
The present study was conducted to survey the prevalence of panicle blast in the long grain indica type rice varieties, Chianung-shien 8 and Chianung-shien 11. 74.83% of 1,702 hectares of Chianung-shien 8 and 28.95% of 4,270 hectares of Chianung-shien 11 were heavily damaged by the disease in the 2nd crop of 1974. In addition to the panicle part, the collar of the leaves were also severely infected by the disease.
The panicle samples were collected from different diseased areas and the pathogen isolated. The isolates of the pathogen were tested to identify the races based on the disease reaction types on the 16 differential rice varieties. Twenty one races, including 5 new races and 16 previously identified races, were obtained. The further investigation comfirmed that 13 races belong to group I, 2 races belong to T group, 4 races belong to K group, and one race each belong to groups N and A respectively.
It was also found that the races 51 and 55 invade exclusively to Chianung-shien 8 and race 31 and 51 to Chianung-shien 11. Results indicated that there are more races infecting indica type rice varieties
(13(3):44-50)STUDIES ON THE DRUG RESISTANCE OF PIRICULARIA ORYZAE AGAINST MERCURIC CHLORIDE
No full text本試驗係於實驗室內探討兩種不同生理小種之稻熱病病原菌，由於連續施用水銀劑後是否可能產生變異性耐藥菌種而舉行，其結果簡述如下：
1. 致病力強之稻熱病菌生理小種，對 HgCl2 之自然抵抗性為0.050mM，致病力弱之生理小種為0.082mM。
2. 供試兩生理小種對水銀離子顯示不規則之耐性增強。培養至第六代達0.375mM為最高耐性。此後再連續培養四代，均未有增加耐性之趨勢。
3. 供試耐藥菌（0.114 mM）之兩種生理小種，連續培養於無藥劑之基本培養基內，其對水銀離子耐性之增加一致保持在0.20 mM，似可認本菌對水銀離子具有永續耐性。
4. 根據處理前與處理後之菌種接種於16種稻品種上所呈現病斑之差異，測定其病原性之結果，耐藥菌之病原性均強於連續培養後之正常菌，與處理前母菌之病原性比較，致病力強之生理小種耐藥菌與母菌完全相同，連續培養之正常菌且有退化現象。致病力弱之生理小種耐藥菌及正常菌均比母菌為強。
In order to determine the drug resistance of Piricularia oryzae, the rice blast fungus, against mercuric chloride (HgCl2), two different physiologic races of P. oryzae were tested in this experiment. The results are summarized as follows:
(1) The natural drug resistance of OS-45S, a strongly virulent race is at 0.05 mM; while 1C-32S, a weakly virulent race, at 0.082 mM.
(2) When the two different races of P. oryzae was cultured on the potato dextrose agar medium containing different concentrations of HgCl2 for 6 stages (one stage is formed of 2 weeks culture). The fungus acquired the highest degree of drug resistance at 0.375 mM.
(3) Even if the drug resistant fungus at 0.114 mM is cultured on the normal medium containing no mercuric chloride for 10 stages (one stage is formed of 2 weeks culture), its resistance is not lost.
(4) Comparing the disease reactions of 16 differential rice varieties to the drug resistant cultures with to normal 10-stage cultures (successive cultivation on normal medium containing no mercuric chloride) of these two different races, the drug resistant cultures of both races are stronger in infectivity than normal 10-stage cultures of them. While compared with mother cultures, the drug resistant culture of OS-45S race showed the same virulence as its mother culture, but the normal 10-stage culture became weaker in virulence. However, the drug resistant culture and normal 10-stage culture of 1C-32S race were more virulent than their mother culture
STUDIES ON THE SHEATH ROT DISEASE AND ITS RELATION TO THE STERILITY OF RICE PLANTS
No full text自典型病斑所得菌株之最適生長溫度為32℃，自不稔病株葉鞘褐孿部位所得菌株之最適溫度為30℃，故葉鞘腐敗病菌之生長最適溫度在30~32℃。但稻葉鞘腐敗病病勢進展之最適溫度為26~28℃，比病原菌生長之最適溫度稍低。
不稔病區之水稻在稻形成幼穗後不久，自該幼穗就可分離到葉鞘腐敗病菌，一直到成熟期皆可獲得病原菌，一般穀粒的穀殼上潛伏病菌之頻度比糙米多。
水稻受傷痍時其惑染率可達88%以上，而無傷痍稻較難被惑染。稻細蟎體，蛻皮或卵上附著甚多的病原菌，因此稻受稻細蟎加害時，亦容易引起病害之發生。
放飼稻細蟎後接種病原菌對稻不稔之影響，比單獨接種病原菌或放飼稻細蟎區為大。
160個品種在自然環境下，被惑染葉鞘腐敗病之程度，日本型稻群比印度型稻群內之感病品種較多。
This paper deals with the rice sheath rot pathogenic fun gus, Sarocladium oryzae, influence, of. sheath rot disease and tarsonemid mite on the sterility of rice plants. The experimental results showed that S. oryzae had a wide range of temperature for growth. Tests of 3 S. oryzae isolates (SO-1 and SO-2 were isolated from brown tissues of rice sheath, SO-3 was from typical lesion of sheath rot) indicated that the favorable temperature for growth of SO-1 and SO-2 was at 30℃ and for SO-3 was 32℃. Therefore, the optimum temperatures for growth of S. oryzae were from 30 to 32℃. Favorable temperatures for disease development were lower than that for the growth of S. oryzae. The optimum temperatures for disease development were around 26-28℃.
S. oryzae could be isolated from young-head shortly after young-head formation and until maturity. It was more easy to isolate S. oryzae from grain shell than from brown rice. The percentage of infection could be reached 88% when rice plants were injuried. However, it was difficult to establish the infection without wounding. A lot of conidia were adhesive on the bodies of tarsonemid mite. Pure culture of S. oryzae could be easily obtained from bodies, ecdyse or eggs of tarsonemid mite. Rice plants inoculated with mite and S. oryzae were more severe than those plants inoculated with S. oryzae or mite alone.
Among 160 rice varieties under natural conditions, japonica type werer more susceptible than indica type to sheath rot disease
(13(2):39-45)SOME OBSERVATIONS ON THE OUTBREAK OF RICE SHEATH-ROT DISEASE
No full text本報告係關於稻葉鞘腐敗病之病原菌（Acrocylindium oryzae Sawada）之生存力，被害稻對產量因子之影響，該病之發生與其他病害蟲之關係，稻品種間之罹病程度，以及該病之發生與施肥之關係等諸項在田間或室內之觀察結果，摘述如下：
1. 稻葉鞘腐敗病病原菌放置於冷藏室（15℃）或室內（15~28℃）溫度下，其生活力到第10個月呈較衰弱，第12個月時即失去生活能力。
2. 被害稻不能抽穗狀況，蓬萊稻似較在來稻嚴重。被害稻之糙米的長度，寬度及厚度等均比健全稻之糙米為短、薄。故如大發生時對產量之影響頗大。
3. 本病之被害穗莖，被螟蟲害者有56~57%之多，罹黃萎病者有7~21%，而被害穗均無其他病害蟲之侵害者僅有22~35%。
4. 觀察209稻種之感病程度，在田間自然發生率在2.1~5.0%之間佔大多數，又一般看之印度型稻草內之品種較日本型稻羣內之品種的感病性品種稍多。
5. 增施氮肥之用量時，其發病率稍有增加，又鉀肥之分施也有增加發病之傾向。
1. When the artificial cultures of Acrocylindium oryzae Sawada were kept either in a cold room with constant temperature at 15°C or at room temperture (15-28°C), the vitality was greatly affected after 10 months. In fact, the viability was completely lost after 12 months.
2. Heading was greatly impaired by disease, particularly with Japonica type rice plants. Indica type was rather mild. The healthy grains were much better than the diseased ones in terms of length, width, thickness.
3. The necks of panicle affected by sheath-rot were respectively destoryed by borer and yellow dwarf at the rates of 56-57% and 7-21%. Diseased panicles free from other pests were only 22-35%.
4. Varietal resistance was also investigated among 209 rice varieties in paddy fields. Most of them were damaged at the rate of 2.1-5.0%. The susceptible varieties were found slightly more in Indica type than in Japonica type.
5. The outbreak of disease increased in proportion to the amount of nitrogen fertilizer applied. The diverse tendency was observed in the lots using potash fertilizer
Studies on the Effects of Some Fungicides on the Three Important Causal Fungi of Rice Diseases
No full textAssessment of Yield Losses due to Rice Blast Disease
No full text稻生育期間，皆有被稻熱病菌侵害之機會，但一般可分為生育前期所發生的葉稻熱病及抽穗後所發生的他稻然病（包括穗頸、枝梗、穀拉、護穎稻熱病等），較為明顯。兩者間之被害狀況不但有異，對產量之影響亦不同，則前者是間接的，而後者是直接的。如此欲估計其損失程度並非易事。通常稻熱病對水稻產量損失之研究方法，有(1)剪葉（模擬葉稻熱病被害程度），(2)在同一塊稻田採集同級被害程度的樣本，(3)利用殺菌劑控制被害程度等。茲將國內外之估計方法予以介紹
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