頁籤選單縮合
題名 | 臺灣甘蔗育種的研究 |
---|---|
作 者 | 駱君驌; | 書刊名 | 中華農學會報 |
卷期 | 78 1972.06[民61.06] |
頁次 | 頁1-16 |
關鍵詞 | 甘蔗; 育種; 臺灣; |
語文 | 中文(Chinese) |
中文摘要 | 臺灣在甘蔗育種上遭遇到的困難是不易實現特定的雜交組合,以育成特定親本的後代。臺灣甘蔗開花的情形很不理想,多數高貴種,或高貴雜種親本(Hybrid parent)在臺灣天然環境下都不開花。必須利用光期室去誘致開花。至於一些能在天然環境下開花的親本,十、九是生產力很劣,無利用為親本的價值,而且花粉也多半為不孕性,為解決開花問題,我們在臺灣中部之埔里,南部之屏東及南端之恆春各分設一交配圃,另加一座光期室,以增加雜交親本的開花機會。其次,我們集中每年的雜交組合到5至7個親本的花穗上,以一個最優良的親本作為基本親本(Basic parent),分別與四個已經證明的優良親本雜交,成為四個"品系",再由這四系相互雜交,育成吾人所要求的經濟栽培品種。 甘蔗在減數分裂時,同質染色體(Homogenetic chromosomes)常自行配對(Autosyndesis)。假定自行配對的染色體(Autosyndetic chromosomes)負荷了很多優良性狀的基因,則若干自行配對的同質染色體配合在一起,?產生吾人所要求之優良品種。 自1950年起,這育種計畫執行的結果,已推廣了13個經濟栽培的甘蔗品種,佔領了臺灣植蔗面積的90%。 一個經濟栽培種的育成,由47至7,268個實生苗中選拔出來,?數約為1比1,000。祇要組合嚴選,後代數目(Population of progeny)並不太大。 根據我們的經驗,一個優良親本一定能將它的優良性狀傳遞給其後代,且在細胞減數分裂時(Meiosis),單價體(Univalents)很少,花粉多為孕性。母本對於後代的營養生長(莖長及莖徑)有很大的影響。父本則與蔗糖的遺傳關係最大,多半是自交後代或近親雜交後代。 在加入某些特殊性狀,以增加品種的生產力,或適應力方面做的工作很多,部份甚為成功。 |
英文摘要 | The purpose of this report is to present the results of research work on sugarcane breeding basing the practival experience and hypothesis forming through field observations in Taiwan. As a polyploid, the heritable pattern of sugarcane is still a dazzle if not a mystery. In the history of sugarcane breeding since 1888, the increase of seedling production to increase the probability of superior selection has been employed by the sugarcane breeders as the principal method. Their primary concern is raising seedlings as much as possible. For example. Hawaii raises seedlings up to one million or more in a year. It is very expensive indeed. This is followed by difficult job of screening approximately 97% seedlings produced annually. The techniques of raising of sugarcane seedlings were greatly improved in recent years and millions of seedlings can be raised a year if the money and labour were available. One even can raise sugarcane seedlings from tissue culture or single cell suspension culture pioneered by L.G. Nickell in Wawaii recently. However, the problem remains. Basicly, it is not number of seedlings raised but the number of superior selections produced. It is a problem of quality not quantity. Apparently, the quality of the can be greatly improved if the crosses and parents had been highly selected and proved from progeny. The voluminously cytological works done by the sugarcane cytologists agreed in one conclusion, that is the autosyndesis of homogenetic chromosomes in meiosis is generally a rule in sugarcane and the majority of chromosomes is bivalents as seen in metaphase I. Assuming the autosyndetic chromosomes as the linkage groupe to lock the genes which govern the desirable characters, then the extent of reassortment and recombination of the autosyndetic chromosomes from the partners of a cross would determine the superiority of the progeny. It is superior if the desirable characters were surpassed those of undersirable ones, while it is poor if the reverse is true. Taiwan has difficulty in sugarcane breeding to produce seedlings from the particular parents and particular crosses. The flowering conditions were extremely poor. Most of the noble and noblized hybrid parents were not flowering under natural conditions and must be induced in the photoperiod house. While those flowering were inferior in productivity and poor in pollen grains. To solve the flowering problem, first we extablished 3 crossing plots in central, south and south pole of this Island plus induction treatment in the photoperiod house. And, second, concentrating all effort to increase the tasselling of five to seven major breeding elites. Using one superior elite as the basic elite to cross with four other elites to develop four "lines" to intercross for commercial selections. This has narrowed the crosses between highly selected parents and greatly increased the superior selections. Among 13 commercial varieties bred in the past two decades, 8 were selected from a population of 45 to 1,140 and 5 from 1,141 to 10,463 seedlings. It reveals that a population of 1,000 to 2,000 seedlings would be large enough for tone commercial selection if the partners of the cross were carefully selected. Assuming all desirable characters of the superior selection were carried by the autosyndetic chromosomes, then 10 to 11 pairs of homogenetic chromosomes were involved. It is 1/5 to 1/6 of a "triploid" which theoretically has 100 to 120 somatic chromosomes. It is the reason that we feel no pressure on heredity diversity though the breeding programme has been carried on for twenty five years from now. Most of the commercial varieties released in recent years were the F2 (2 were F1) of PT 43-52, the basic parent. As to adaptability, it was assumed that the macro-environment, the climatic and edaphic factors, controls productivity while the micro-environment, the night temperature, daylength, rainy days and special texture and pH of soil of the particular area, controls adaptability. Productivity involves many chromosomes while adaptability controlled only by few genes. Incorporation of desirable genes into any desirable autosyndetic chromosome would finally improve adaptation without effects and productivity. The same is true to disease resistance. |
本系統之摘要資訊系依該期刊論文摘要之資訊為主。