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(31(4):265-274)Genetic Studies on Grain-Length by Partitioning Method in Rice
No full text以水稻品種Mira（Pl）× Norin20（P2）之兩個親本及其Fl 與F2等四個集團為材料，探討控制水稻穀粒長之遺傳行為。經使用遺傳分析析出法分析之結果發現：兩說本穀粒長之差異係由兩對有效因子對所支配，且穀粒短者（P2）對長者（Pl）為部份顯性，兩親本Mira（Pl）及Norin 20（P2）之穀粒長基因型分別被訂為aabb 與AABB 。因子交感作用之估算結果顯示對立因子對A 對a 有高度之部份顯性；而對立因子對B 對b 亦有相當程度之部份顯性，A 因子與a 因子之置換，在不同之基因型遺傳背景下對穀粒長之效應並不盡相同；B 因子與b 因子之置換其結果亦同。因知此兩因子對非為重覆基因。綜言之，A 與a 基因對及B 與b 基因對之顯性程度視其所處遺傳背景之不同對稻穀粒長之支配而有若干不同程度之變異。
Two rice vane varieties, Mira (P1) and Norm 20 (P2) were crossed for determining the number of effective factor pairs controlling grain length. It was found by applying the partitioning method of genetic analysis that the two parents were differentiated by two effctive factor pairs. The data indicated the existence of partial phenotypic dominance for shoter length of grain (P2) over longer one (P1).
The genotypes of Mira and Norm 20 were symbolized as aabb and AABB respectively. In studing factor interactions it was found that factor A exhibited a higher degree of partial dominance over its allele a in all genotypes. However, the dominance relations between B and its allele b were not consistent for the different genotypes. In substitution of a for A, the different genotypes did not have the same effect upon grain-length as did the substitution of b for B in the corresponding genotypes It follows that these two factor pairs are not duplicates. The conclusion drawn was that the degree of dominance with .Iegard to both A and a; and B and b was dependent upon the genetic background
(30(3):215-218)Studies on yield potential of Tainung 67 rice - I. The performance of yield components
No full text為檢討水稻臺農67號之產量潛能，本試驗以臺南5號為對照，藉兩品種諸主要性狀之比較，以推定臺農67號高產之決定性狀。經1年兩期作之試驗調查發現：在1期作生育條件下，臺農67號較對照種臺南5號增產9.1%，其差異已達5%之顯著水準。而其高產之癥結似因臺農67號之穗數較對照種臺南5號者為多，致單株之生物產量增加而穀產量增加，而與兩品種之收穫指數無關。而在2期作環境下，臺農67號豐產之癥結如一期作者，亦奠基於該品種之多穗數。惟本期作下，臺農67號雖較對照種臺南5號增產4.2%，但兩品種單株穀產量之差異並未具統計上之意義。The recently released high yielding rice Tainung 67 is currently the most popular variety in Taiwan. In order to evaluate the yield potential of this variety, various yield components, economic yield, biological yield as well as harvest index were studied in comparison with the past high yielding variety Tainan 5.
Tainung 67 yielded 9.1% higher than that of Tainan 5 in the first crop at 5% level of significance. This was found to be due mainly to the larger mumber of panicles which lead to an increase of biological yield in Tainung 67. No difference in harvest index between Tainung 67 and Tainan 5 was observed. In the second crop, Tainung 67 gave 4.2% higher grain yield than Tainan 5; it was found to be due to the similar reason as that observed in the first crop
(34(4):402-409)A Pereliminary Report on Developing Larger-seed Isogenic Line of Rice Variety, Tainung No. 67
No full text以糙米百粒重2.0g 左右之臺農67 號及3.5g 左右之Pegonil 兩品種為親本，其正反交之兩Fl 後代再與輪迴親本臺農67 號連續回交，期育成臺農67 號大粒isogenic 系統。本文即在初步報導此育成過程中之若干結果。Fl數據顯示糙米百粒重無正反交之差異。TNG67 / Pegonil / TNG 67 集團糙米百粒重平均為3.09 g.，集團常態分布於兩親本間；反之，Pegonil / TNG672 之糙米百粒重僅達2.29g ，集團分布集中且靠近輕百粒重親本臺農67 號。穗數、一穗穎花數及單株糙米產量等重要性狀TNG 67 / Pegonil / TNG67 集團者均較Pegonil / TNG672集團者為低。綜合考慮此等初步結果認為育成臺農67 號大粒isogenic 系統以繼續臺農67 號為母本之後代集團之選株連續回交輪迴親臺農67 號較有希望。
The present experiment is aimed to develop the larger-seed isogenic line of Tainung No. 67 (TNG 67), which is now the most popular variety in Taiwan. In the Fl crosses between TNG 67 (2. 0g/100-brown-rice) and Pegonil (3.5g/100-brown-rice), no significant difference was observed in sees size between the reciprocal crosses. In the BCl generation of TNG 67/Pegonil/TNG 67, seed size distributed normally with a mean value of 3.09 g/l00-brown-rice. However, in the population of Pegonil/TNG 672, seed size distributed skewly toward TNG 67 with a smaller mean value of 2.29 g/l00-brown-rice. Characters such as panicle number per hill, spikelet number per panicle and bro wnrice yield per plant in the population of TNG 67/Pegonil/TNG 67 were all found to be smaller than those in the population of Pegonil/TNG 672.
From this preliminary study, it is conclued that developing a larger-seed isogenic line of Tainung No. 67 by repeated back cross and using TNG 67 as the recurrent parent and Pegonil as the donor parent should be promising
(30(3):219-226)Genetical and breeding studies in the crosses between indicu x sinica rices - I. Path coefficient analysis of single-plant grain yield
No full text本研究以秈×稉與稉×秈等兩個雜交組合之F2集團為材料，探討秈稉稻雜交後代產量構成要素對單株穀產量變異之決定程度，結果發現：兩種組合中，單株穀產量與產量構成要素間均呈極顯著之正相關。路徑係數分析結果則顯示兩種組合中，產量構成要素對產量變異決定程度的大小順序並不一致。在秈×稉組合中，對單株穀產量變異最具影響力之性狀為穗數，其次為平均一穗穎花數，再次為結實百分率，終為千粒重；稉×秈組合中，產量構成要素對單株穀產量變異之決定程度的大小則依次分別為結實百分率、穗數、平均一穗穎花數、千粒重。文中曾對此等結果加以討論，並建議育種家從事秈×稉或稉×秈雜交育種時，穗數及平均一穗穎花數為譜系汰選拔時之兩個重要選拔指標。The prestent studies are to compare the effect of four yield components on the variability of single-plant grain yield of rice in indica x sinica and sinica x indica crosses by the technique of path coefficient analysis.
The significant positive correlations between four yield components and single-grain yield were observed in both crosses. From the path coefficient analysis, it was observed that the order and degree of effect of the respective yield component on the grain yield differed from cross combination The order of effect on grain yield was found to be number of panicles, mean number of spikelets, percent seed setting and 1,000 grain weight in the indica x sinica cross; and percent seed setting, number of panicles, mean number of spikelets and 1,000 grain weight in the sinica x indica cross.
It was suggeted that in rice breeding, number of panicles and mean number of spikelets should be used as the main selection criteria for selecting grain yield from either indica x sinica or sinica x indica cross
(31(3):177-186)Genetical Studies on Grain Characters in Rice
No full text本試驗以Mira（Pl）× Norin 20（P2）組合之包括Pl、P2、Fl、F2、BCl及BC2等六個遺傳集團為材料，探討該組合稻穀之粒長、粒厚、粒寬及百粒重等4 個穀粒性狀之遺傳行為，結果獲知：粒長、粒厚、粒寬及百粒重等4 個穀粒性狀在F2集團之頻度分布圖形均呈連續性分布，但4 穀粒性狀分布圖形之樣式則不盡一致。雜種優勢、純雜種優勢及自交衰退量等三種遺傳介值普遍存在4 穀粒性狀，其經以Potence value 判定4 穀粒性狀在Fl之顯性程度及Mather and Jinks 變方成分劃分以評定4 穀粒性狀顯性度之估算結果十分近似，均呈短粒對長粒及粒厚對粒薄為不完全顯性；粒寬為超顯性；粒重方面則為微小程度之不完全顯性。經世代平均值分析指出，粒長及粒重之遺傳變異由累加性、顯性、累加性 × 累加性交感、累加性× 顯性交感、顯性 × 顯性交感等成分所支配，且兩性狀之顯性及顯性 × 顯性之交感等兩成分符號相反，表示屬重覆型之上位性。而粒厚之變異主要係累加性、顯性及累加性 × 累加性交感成分之效應。粒寬之變異則由顯性及累加性 × 顯性交感兩成分之效應所左右。4 穀粒性狀之廣義遺傳率介於82-94%之間，狹義遺傳率介於34-69 %之間，其中以粒長之遺傳率較高，而以粒厚者較低。相關分析之結果發現粒重與粒長、粒厚及粒寬均呈極顯著之正相關。
Genetical studies were made on four grain characters in rice using Fl F2 BCl and BC2 populations of the cross between Mira (Pl) and Norin 20 (P2) varieties. The grain length, grain thickness, grain width and 100-grain weight in F2, all showed continuous and unimodal distributions. However, the distribution curves are not symmetrical as indicated by different values of skewness and kurtosis for respective character.
Heterosis, heterobeltiosis and inbreeding depression of each character was detected in Fl of this cross, because the statistic of each characters was significantly departed from the zero value. The degree of dominance of the respective character expressed by potence value and the value estimated by Mather and Jinks’s formula of the comprehension of components of variance was quite similar, i. e. short grain is incompletely dominant over long grain the thick-grain is incompletely dominant over thin-grain; the wider grain is over-dominant to narrow grain and the heavy-grain weight is slightly partial dominance over light-grain weight.
The results of generation mean analysis indicated that the variations in grain length and 100 grain weight were mainly due to the gene effects of additive, dominance, additive × additive, additive × dominance and dominance × dominance. A difference in the signs of dominance and dominance × dominance components was observed, indicating a duplicated type of epistasis. The variation of grain thickness was largely due to additive, dominance and additive × additive gene effects. For grain width, the gene effects of dominance and additive × dominance components appeared to be more important.
The broad sense heritabilities of four grain characters ranged 82-90% while narrow sense heritabilitie ranged from 34-69%. The grain length and grain thickness showed the highest and lowest heritabities respectively among the four grain characters studied. It was observed further that 100-grain weight was possitively correlated with grain length, grain thickness and grain width
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
(33(1):12-23)水稻分蘗之生理研究 II.不同穗部容積品種的生產力比較
No full textAmount of dry matter, total nitrogen and total nonstructural carbohydrates (TNC) in the leaf blades, leaf sheaths and stems from various node positions, as well as panicles, of rice tillers were analyzed at stages of grain development. The purpose of this study was to compare the potential of productivity between a large-grain variety Mira and a medium-grain variety Tainung No. 67. Nitrogen concentrations in various organs of Mira tillers were significantly higher, whereas TNC concentrations were lower, than those of Tainung No. 67 tillers. When compared to Mira on a per tiller basis, Tainung No. 67 produced 14-55% less dry matter and 36-39% less TNC during the test period. For a mature panicle from a single tiller, the amounts of dry matter and TNC accumulated by Tainung No. 67 were only 61-74% and 63-80%, respectively, of those accumulated by Mira. Those results indicated that the productivity per tiller was greater for the large-grain variety. As panicle number per hill was very low for Mira, community productivity was 50% higher for Tainung No. 67 in the first crop hut was comparable between varieties in the second crop. No difference in the increase rates of major components in panicles was found between varieties, indicating the absolute amount of translocation into panicles was greater for Mira. Results suggested that yield increase through enlarging grain size was possible. However, responses of the large-grain rice to the environmental factors should be further understood.
以大粒種水稻品種 Mira （千粒重約 379 ）及中粒型水稻品種臺農 67 號（千粒重約 25g ）為材料，自抽穗起每週以分蘗為單位取樣，測定源自不同節位之葉片、葉鞘、莖及穗部的乾物重，全氮及非構造性碳水化合物（ TNC ）含量的變化，目的在比較兩型水稻的生產能力。試驗結果發現 Mira 各器官內之全氮濃度顯著較臺農 67 號為高，每一分蘗吸收的氮量亦超出臺農 67 號 40 %以上。在穀粒充實過程的淨乾物質與 TNC 生成量比較，如以單一分蘗為單位，臺農 67 號分別較 Mira 少 14-55 %與 36-39 % ；成熟期時，臺農 67 號水稻之單一穗重僅為 Mira 之 61-74 % ，單一穗內 TNC 含量僅為 63-80 % ，顯示大粒型水稻單一分蘗的生產力較高，而推廣品種亦有再加改良的可能。由於大粒型水稻的穗數太少，故就群落生產力而言，一期作臺農 67 號較 Mira 高 50 %，二期作則兩品種相似，即 Mira 在第二期作有較優良的表現。兩品種穗部主要成份的累積速率相當，表示絕對轉流量以大粒型品種為高。本試驗結果建議，經由增大穀粒體積謀求稻作增產或有可能，但較大粒型水稻品種（系）對各項環境因子一諸如溫度，栽植密度、氮需要量等之反應，仍應先加以深入的瞭解
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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