(28(1):1-6)Breeding and genetic studies for the resistance to bacterial leaf blight disease in indica rice III. on the relationship between the resistance to bacterial leaf blight disease and cold tolerance

利用抗白葉枯病耐寒之Pl 162319 ，分別與感病不耐寒之嘉農秈11 號與嘉農秈育12 號等品種雜交，由其F2及F3 後裔，分別測定其耐寒性及對白葉枯病之反應，以探討控制該兩性狀之遺傳因子是否有相關關係存在，以供育成抗病、耐寒及豐產品種之參考。試驗結果得知F2 族群中抗白葉枯病個體出現之頻度，不因供試材料經低溫處理而顯著的減少或增加。又由F3 後裔檢驗之結果得知，供試兩組合之抗病與耐寒性間之簡單相關係數分別為r =0.1859 與-0.1874 ，均為不顯著。由此可推知，耐寒與抗白葉枯病因子之分離係獨立，似無相互牽制連鎖現象。因此吾人欲育成抗病耐寒之秈稻品種，可以一般育種方法，將稉稻抗病耐寒因子轉移於秈稻品種。 Most of the indica rice varieties in Taiwan are found susceptible to bacterial leaf blight (Xanthomonas oryzae ) and sensitive to low temperature, especially during the nursery of first crop and ripening stage of second crop. The bacterial leaf blight disease seems to be associated with low temperature. It may become severe in indica rice. In order to clear genetic correlation between bacterial leaf blight disease and cold tolerance, experiment was carried out by using introduced rice variety PI 162319 (resistance to B. L. B. and low temperature) to cross with the local varieties Chianung Sen 11 and Chianung Sen yu 12 (Susceptible to disease and sensitive to low temperature). Two F2 populations and their F3 progenies were subjected to genetic analyses. Results obtained from this experiment were as follows : It was found that the differences of the bacterial leaf blight reaction of the two F2 populations between cold treatment and control were not significant at 5% of probability. This means that the two characters segregated independently. There were no significant correlations between bacterial leaf blight resistance and cold tolerance ( r=1,859 and _0,1874 for respective cross) in their F3 progenies. It is recommended to use the japonica rice for varietal improvement of indica rice. Most indica rice varieties are susceptible to cold temperature which can be improved by transfering the cold tolerant gene from the japonica rice

(23(1):1-8)STUDIES ON THE HYBRID VIGOR OF RICE (III) THE RESPONSES IN GRAIN YIELD AND YIELD COMPONENTS OF F2 POPULATIONS AND VARIETIES UNDER FOUR DIFFERENT GROWING CONDITIONS

本試驗主要目的，在探討F2羣體在不同栽培條件下對稻谷產量及產量構成要素的影響。供試材料有臺中65號，F2（臺中65號×臺南3號），臺南3號；光復401號，F2（光復401×臺農38號），臺農38號及臺農61號，臺北309號等8組合。行株距兩處理，即25cm×20cm及25cm×10cm；肥料兩處理，即N-P2O5-K2O分別為80-60-60及120-60-60(kg/ha)。試驗結果以對照品種臺農61號的產量最高，臺北309號居次，臺中65號的產量最差。兩F2羣體的平均產量比其四親本的平均數為高。F2羣體在四種不同栽培環境下的反應，一般而言，均與其親本或對照品種相一致。在第一期作密植對產量無顯著的效果，雖然單位面積穗數因密植而增加，但一穗粒數則相對的減少。增肥在普植區可以增加一穗粒數，卻使千粒重及結實率下降，結果產量低減。增肥密植的結果，一穗粒數並無顯著的增加，千粒重及結實率卻顯著的下降，而使產量低落。第二期作除密植顯著的增加單位面積穗數之外，不同栽培環境對水稻的產量及產量構成要素無明顯的效果，但F2羣體在不同栽培環境下的變異範圍似較其他品種為小。水稻本身似具有相當的調節力量，以適應不同的栽培環境。 The objective of this experiment is to compare the responses in grain yield and yield compoents of F2 populations to that of their parents as well as commercial rice varieties under four different growing conditions. Two F2 populations, Taichung 65 x Tainan 3 and Kwanfu 401 × Tainung 38 ; four parents, Taichung 65, Tainan 3, Kwanfu 401, and Tainung 38 ; and two commercial varieties, Tainung 61 and Taipei 309 were used as experimental materials. Two spacings, 25cm × 20cm and 25cm × 10cm, and two nitrogen levels, 80 and 120 kg/ha of pure nitrogen were combined into four different growing conditions, and all F2 populations and varieties were planted under the four treatments. The field layout was a split-split plot design with four replications. In general, the respones in grain yield and yield components of the two F2 populations under four different growing conditions revealed the same tendency as their parents and the two commerial varieties. In first crop of 1971, close spacing increased the panicles per unit area, but decreased the grain number per panicle, showed little response in grain yield. The high rate of nitrogen application positively responsed in grain number per panicle, but negatively responsed in 1,000 kernel weight, percentage of fertility, and grain yield. The close spacing with high rate of nitrogen application could only decline the 1,000 kernel weight, percentage of fertility and grain yield. In second crop of 1971, all the materials planted under different spacings and nitrogen applications did not show any clear trend in grain yield and yield components except the close spacing did increase panicles per unit area. The responses in grain yield and yield components of F2 populations, however, showed a little bit narrower range of variation than the rice varieties under the four growing conditions. The data of this experiment also indicated that rice plant has the ability of compensation through its yield components under different growing conditions

(31(4):255-264)Cold Tolerance of Rice at Seedling Stage - I. The Reaction of Rice Varieties at Different Seedling Stages

本試驗之目的是以植物生長箱檢驗不同苗齡對低溫之反應，並查不同類型水稻品種的耐寒性，以探尋可靠的檢定方法及了解各品種之耐寒性，俾供抗寒育種或有關試驗之參考。使用光照強度為270 Microeinsteins m-2Sec-1，而光照時問12 小時／天，以10℃之低溫處理秧苗9 天，並以秧苗存活率表示其耐寒性。試驗結果摘述如下： 將7 個稉稻品種，13 個秈稻品種共20 品種，每隔3 天播種一次，連續播10次，在低溫處理前，調查參試之20 品種各播種期的苗齡供參考，試驗結果稉稻較秈稻耐寒。參試品種中稉稻以USSR No.45，藤坂5 號，新竹糯4 號較耐寒、秈稻是以臺農秈育2414 及上杭大冬較耐寒。一般說4.5 葉齡的秧苗對低溫最敏感，而在3.5~4 葉齡時耐寒性品種間之差異最大。 以IR 29 與臺農67 號之正反交及其與臺農67 號同交之4 個F2集團在3.5 葉齡時，進行耐寒性檢定。結果，臺農67 號為耐寒品種，而IR29 對低溫極敏感，且臺農67 號之耐寒性主要受一對顯性遺傳因子控制。 以162 個水稻新品系在3~3.5 葉齡時，進行耐寒性檢定。結果只有10 個品系之存活率高於80%，而存活率在61~80%的亦只有3 品系，顯示新品系對低溫敏感，應於育種時引進耐寒基。 The main purpose of this experiment was to research the basic data for screening cold tolerant vaieties and breeding matherials of rice. A plant growth chamber was used to control the air temperature, which was set at 10°C for 9 days. The light intensity was 270 Microeinsteins m-2Sec-1for 12 hours per day. The experimental results were summarized as follows: Seven Japonica and thirteen Indica rice varieties were used for this experiment. All twenty varieties were planted ten times at 3 day intervals. The leaf age of each rice variety at each planting was recorded just before low temperature treatment. (see Table I) The results showed that Japonica rice varieties were more tolerant to low temperature than Indica rice varieties. Among the cold tolerant varieties, Fujisaka 5 and Hsinchu Waxy No. 4 are Japonica rice varieties, while Tainung Sen Yuh 2414 and Shang Hung-Ta-Dong are Indica. Based on the survival rate of seedlings, the most sensitive stage was at 4.5 leaf age, while the biggest varietial differences was at 3.5-4 leaf age. According to the basic information mentioned above, four F2 cross-combinations were used for screening the cold tolerant plants at 3.5 leaf age. The rate of survival plants of each F2 Population was recorded in Table 3. It showed that IR29 was a cold susceptible rice variety, and Tainung 67 was a cold tolerant variety. Based on the four F2 populations, cold tolerance of Tainung 67 was found to be governed by one pair of dominant genes. In addition, 162 rice strains were used for cold tolerant testing at 3-3.5 leaf age. Only 10 strain had a seedling survival rate higher then 80%. The results indicated that most of the breeding materials tested were cold susceptible. Therefore, we may conclude the cold tolerant genes should be transfered into the breeding program, especially for indica rice

(25(4):269-272)BREEDING AND GENETIC STUDIES OF BACTERIAL LEAF BLIGHT (XANTHOMONAS ORYZAE) RESISTANT VARIETIES OF INDICA TYPE OF RICE－II. Inheritance of resistance to bacterial leaf blight disease in rice variety, BJ 1

為研究水稻品種BJ 1等對白葉枯病抗病性之遺傳行為，利用感品種臺中在來號與高雄秈2號分別與BJ 1等抗病品種雜交，並於雜交後裔與親本在孕穗期間進行病原菌人工接種，接種20天調查其發病程度。試驗結果，BJ 1與TKM 6品種為親本所得F1、F2及F3雜種裔之反應，顯示水稻種品BJ 1具有抗病性，係受一對隱性因子控制；而控制TKM6之抗病性則對顯性因子，為後者與IRRI試驗結果一致。 The objective of this study was to investigate the mode of inheritance of resistance to bacterial leaf blight in rice variety BJ 1 (TKM 6 used as a check). The experiment was conducted at Taiwan Agricultural Research Institute in 1973. Two susceptible varieties Taichung Native 1 and Kaoshiung sen 2 were crossed with BJ 1 and TKM 6. The clipping method of inoculating the flag leaves was used for the test of bacterial leaf blight. Reaction was scored 20 days after inoculation on a scale of 0-9 based on the extent to which the lesion spread downward from the cut of inoculation. A score of 0 indicated the most resistant reaction, and 9, the most susceptible. Results from the genetic study of parental varieties, F1, F2 populations and F3 families of various cross combinations were given in Figs. 1 and 2 and Table 1. The reaction of the hybrid fitted the hypothesis that resistance to the bacterial leaf blight in rice variety BJ 1 was conditioned by a single recessive gene while that TKM 6 was controlled by a single dominant gene

(18(3):1-18)STUDIES ON THE HYBRID VIGOR OF RICE (1) SCREENING TEST ON HYBRID VIGOR OF RICE

1.本試驗為探討水稻品種間，有關穀粒產量是否有什種優勢，以及其利用價值為目的。曾什交160個組合，但秧苗期遭遇冷害之影響，實際供試驗者有90個什交組合。 2.供試F1中有65個什交組合，表現有抗寒之優勢，此抗寒因子似係顯性因子之控制，但另有19及40個組合顯示為可加性及隱性因子所控制。詳細之遺傳行為，有待進一步之研究。 3.植高及分蘗在什種F1之生長初期，多數的組合有什種優勢之表現，但隨植株高度之增加，即後半期，此表現似有減退之現象，尤其株高較為明顯。 4.什種F1之抽穗期，組合間雖有差異，但多數比較早抽穗親本早或相同。 5.有關穀粒產量，共有44個什交組合F1，表現有什種優勢。多數係穗數及一穗粒數等因子之貢獻其中以H276（臺中176號 × 臺中150號）及H104（臺農60號 × 光復401號）等組合之優勢表，現最佳，高達60%之多。產量高於對照品種臺中65號者有31個組合，但優於另一對照品種臺南3號者僅有H55（臺農38號 × 光復401號）及H24（臺南3號 × 臺中65號）。 6.植高及分蘗在F2各組合間之差異不大，但生育日數差異較明顯，最早者為H145（愛國 × 臺中186號）僅94天，最晚者為H130（PiNo2 × 高雄135號）多達129天之多。成熟整齊度除H145，H83及H18等較整齊之外其他組合不太整齊。 7.什種第二代之產量檢定，經統計分析結果，組合間有顯著差異，其中以H18（臺農選3號 × 吉野1號），H276（臺中176 × 臺中150號）等7個組合之產量最佳，此些組合在Fl亦有同樣優良之表現。 1. Originally 160 cross-combinations were made between rice varieties but the serious cold temperature killed some of the F1 seedlings. Only 90 cross-combinations were used for studying the hybrid vigor of rice and its practical value in terms of grain yield. 2. The primarily test for the cold resistance showed that 65 cross combinations of F1 hybrids were controlled by dominant genes, 19 cross-combinations were controlled by additive genes, and 40 cross-combinations were controlled by recessive genes. However, a further study on the heredity of rice resistant to low temperature will be necessary to clarify the genetic behavior. 3. The hybrid vigor in terms of the growth of plant height and number of tillers during the first five weeks after transplanting were obvious. However, the hybrid vigor were decreasing after the seventh weeks, especially the growth of plant height. 4. Most of the F1 hybrids showed earlier in heading than their early-maturing parents, though some cross-combinations showed later in heading than their parents. 5. Hybrid vigor in terms of grain yield showed that 44 cross-combinations produced more grain yield than their higher yield parents, mainly due to the increase of panicle number and spikelets per panicle. Among the F1 hybrids, H 276 (Taichung 176 × Taichung 150) and H 104 (Tainung 60 × Kwaugfu 1) showed the highest hybrid vigor, produces 60% more than the higher yield of their parents. Comparing with the commercial varieties, 31 cross-combinations produced more grain yield than Taichung 65, but only H 55 (Tai- nung 38 × Kwangfu 401) and H24 (Tainan 3 × Taichung 65) produced more yield than Tainan 3. 6. In the F2 generation, the variations of plant height and number of tillers among the various cross-combinations were small, but the variations of growth period were obviou-sly different. The earliest maturing F2 hybrid was H 145 (Aikoku × Taichung 186) only 94 days. The latest hybrid was H 130 Pi No.2 × Kaohsiung 135) taking 129 days for maturity. Most of the hybrids showed unequal on grain maturity except H 145, H 83, and H 18. 7. The results of the grain yield trail between cross-combinations in F2 generation showed significant difference. Among the hybrids seven combinations including H 18 (Tainung selection 3 × Yoshino No.1) and H 276 (Taichung 176 × Taichung 150) produced promising yield in F2 generation as well as in F1 generation

(16(2):35-48)STUDIES ON THE VARIETIES OF RICE INTRODUCED FROM SOUTHEAST ASIA

1.本試驗為探討來自東南亞之水稻品種之特性與其經濟價值，逐自民國47至49年，就引進之278品種，於農業試驗所進行調查與研究，並以所得結果，供今後稻作改良上之與材料參考。 2.根據第一年觀察結果，第二年將所有供試品種，依其適宜栽培時期分別於4月3日，5月25日，7月2日與7月23日等四個時期插秧，供試品種數第一期為31品種，二期作82品種，三期作97品種，四期作67品種。根據試驗結果，此類品種對於日照長短的反應較敏感，同時在生長期間需要較高溫及較長的時間，故其生育日數較本省一般栽培稻為長，甚至有少數品種在本省一年兩期的水稻生長環境下，不能行正常抽穗，必須在「中間作」始能開花結實。 3.供試稻種劍葉長度，平均為39.5公分，其中以SO區之品種較長，如Semoro mangga和Godi種，其長度均達53.9公分；最短者為菲律賓的Macan Barrel與爪哇47號只有26分公。劍葉寬度平均雖然為1.8公分，但菲律賓與Ba地區之多數品種均在平均寬度之上，佛與印度區之品種較狹，分佈僅在1.0-1.5公分。劍葉角度變異性頗大，其分佈在10-117度之間，平均為55.6度，其中以SO區品種之角度較大，其次為Ba與佛，印度種則最小。 4.植株高度，多數均在145公分左右，共有82%的品種超過130公分，最高有菲律賓之Linleng，印度18號與佛區之R.T.S.3號，均達180公分，最低者有印度11號與R.T.S.26號，不及115公分。莖稈粗細平均為4.4公厘，較一般本省栽培稻粗大，同時具有較大之稈強，尤其菲律賓有72%品種的莖徑超過4.9公厘，並且有73%之品種莖強在300克之上。 5.供試品種之穗長，平均雖然是25.9公分，但是Ba地區絕大多數品種均達30公分以上，其一穗粒數多達176粒，其次菲律賓、SO與CE等區品種之穗長平均為27公分，一穗粒數均在150粒以上，並且該地區有一半以上之品種其穗重超過3克，著粒密度為60粒以上。 6.各品種之千粒重變異很大，最重者有34克，最低僅有15克左右，一升重平均為54.9克，其中菲律賓之Kinan Kuda不但具有最高千粒重，同時一升重及糙米千粒重均冠於所有供試品種。一株穗重分佈於72克（R.T.S.17）至19克（Maraja）之間，平均為35.4克，其中佛區品種不但具有較多的有效分葉，同時一株穗重亦大。 7.糙米長度，平均為5.8公厘，較一般本省栽培種與日本稻為長，尤其菲律賓、佛與SO等區品種之粒長均有6公厘以上。粒寬却介於本省蓬萊稻與在來稻之間，平均為2.7公厘。米粒形狀絕大多數屬長粒型（2~3）少數為短粒與狹粒型，圓粒型（1.4以下）於本試驗中無發現。米粒大小，多數品種屬小粒與中粒者（12~20），兩極端之品種亦無發現。 8.幼苗稻熱病之檢定結果，供試之品種中，一半屬抗病與免疫者，21%為中等抗病，其餘20%屬感染者。 9.本試驗引進之東南亞稻種，目前於本省似不能直接栽培，但有關數量性狀等因子，却可供本省改良稻種之良好材料。 1. Two hundred and seventy eight varieties of rice introduced from the rice producing countries of Southeast Asia, such as Philippineo, Soembawa, Indochina, Celebes, Tailand, Malaya, Java, Lombock, Flores, Bali and India etc. were studied in order to get informations to be used for breeding purposes. Various morphol-ogical as well as physiological characteristics such as plant height, length and width of leaf blade, tiller and panicle numbers per plant, the strength of culm to prevent from breaking, number of grains per panicle, shape and size of grains, weight of 1,000 grains, blast disease resistance and date of maturity etc. were studied. 2. The varieties which did not head when planted in the regular 1st and 2 nd crop seasons, due to different photoperiodic responses, were further planted in four different seasons i. e. April 3, May 25, July 2 and July 23. It was found that the majority of vatieties tested were late in heading as compared with Tai-wanese varieties. The days from transplanting to heading of the varieties tested were 79-91 days (89 days in check) in the 1st crop, 135-150 days (105 days in check) in the 2nd crop, 87-138 days (64 days in ceeck) in the third crop and 64-98 days (69 days in check) in the fourth crop. Some early maturing varieties were found in India and Java groups, while most of late-maturing varieties were found in Indochina, Celebes and Soembawa groups. 3. The length of flag leaf as an average of all varieties investigated was 39.5 cm.; Semora mangga and Gadi from Soembawa had the longer flag leaves, while Macan Barret from Philippines and Java 47 had the shortest flag leaf. The average width of leaf blade was 1.8 cm. in those varieties, Philippines and Bali varieties such as Keta mee, Dari djawa and Poetih menlk Don 1 etc. had wide leaf blade, While some Indochinese and Indian varieties such as 70b sóm câu, IV Tam lun and India 7 etc. had leaves as narrow as 1.0-1.5 cm. in width. The angle of flag leaf to ear was found to be quite variable, as from the widest Soe-mbawa group to narrowest India group. 4. The plant height was 145 cm.; Linleng, India 18, R.T.S. 3 etc. had the tal-lest plaht height (180 cm.) while that of India 11 and R.T.S. 26 etc. was shortes (114 cm.). The stem of the majority of Philippino varieties was generally bigger with 4.9 mm. culm diameter and had 300 g. of culm strength to prevent from breaking. The ear length as an average of all varieties concerned was 26 cm.; but the varieties from Bali, Philippines, Soembawa and Celebes had longer and heavier panicles when compared with other varieties. 5. The weight of 1,000 grains and the weight of one-liter brown rice varied greatly wider, the average of 15-35 g. and 48-63 g. respectively. The yield of single plant ranged from 19. (Mraja) to 72 g. (R.T.S. 17); the average being 35.4 g. 6. Except a few varietie which showed short or medium in grain length, most of varieties tested within the present study had long grains. The average length and width of brown rice were 5.8 and 2.7 mm., respectively. The average ratio of length/width and value of length x Width of grains were found to be 2.5 and 15 respectively. 7. It was found that 59% of the varieties testaed in seedling stage showed either non-infection or resistant reaction to blast disease, while 21% and the remaining 20% of the varieties tested showed intermediate and susceptible react-ions respectively. 8. It was concluded from the present observation that although the majority of varieties from the Southeast Asia were not suiteble for the imediate cultivat-ion in Taiwan, however, there were many desirable characters can be introduced into Taiwanese varieties through hybridization breeding, such as panicle numbers, lenght of panicles, number of grains per panicle, size of grain and blast disease resistance etc

The management strategy based on the effects of climate change on crop pests

目前大家已能接受全球氣候變遷對生態系統會產生重要影響，這結果多數是藉由經度與緯度變化的角度切入研究。雖然如此，但過去百年以來，台灣仍缺乏農業長期變化與空間分布因子的相關研究。有鑑於此，本研究目標包括蒐集往昔科學研究報告所示之農作物有害生物資料，從中分析農業生態系統之中作物有害生物 (病原、害蟲、雜草)與作物、栽培措施及氣候因子的相互關係，建立一個可以預測氣候暖化對有害生物分布影響的管理策略。 It is now widely accepted that global climate change is affecting many ecosystems around the globe and that its impact is increasing rapidly. Many studies predict that impacts will consist largely of shifts in latitudinal and altitudinal distributions. However, the related studies on long-term changes and spatial distribution characteristics of agro-climatic conditions in the past 100 years in Taiwan are still unknown. Accordingly, the present project has following goals: i) to glean available information from the historically scientific papers associated with mainly crop pests of Taiwan; ii) to analyse the relationships among the pests (e.g. pathogens, insect pests, and weeds), crops, cultivated techniques, and climatic factors in agro-ecosystem, and then, to establish a management strategy to predict the effects of climate warming on species distribution of crop pests