田作育種의 最近의 進步

Recent Advancement in Upland Field Crop Breeding

Several models of breeding schemes which are to be contributed to the upland field crops in Korea are discussed. Upland field crops in Korea are in a worse sutuation of their geographical and management conditions, and they are sincerely required to be more stable and higher is yield of variety itself compared to the other crops. In self pollinated crops, the recurrent selection schemes which have been mostly used in cross pollinated crops are desired to be a breeding scheme, facilitated with genetic male sterility, to improve yield and other characteristics such as pest tolerance, and the plant type regards. to the characteristics of stalks or stem, leaves and ears etc are also important part to develop a variety of further higher yielding with increased utilization of solar energy and maximized dry matter production. Beside the accumulation of beneficial characters by means of inter-specific hybridization have been well known already recently, a chemical treatment of E-amino caproic acid(EACA) is attempted to help the inter-specific hybridization. The value of triticale as a new crop developed from the interspecific hybridization is being recognized, so this new crop is desired to be adapted and utilized in Korea and breeding schemes by means of inter-specific hybridizaion in the other crops are to be considered. In early and high yielding breeding program, particularly in wheat and barley, introduction of new gene source along the analyized results of internal factors of heading-ecotype, and selection dued to cold tolerance, winter habit and heading date in different location and paddy and upland field conditions are recommended according to the daylength response and true earlyness of Takahashi’s study. According to the demand of effective breeding technology against the occurrance of new strain or biotype and reduction of damage of disease and insect in upland field crops, chromosome engineering to replace a tolerant gene is a elaborated genetic technology and is to be emphasized as a new field to be developed. The breeding purposed on better nutritional content is one of the important program which is aimed internal yield increase by the increase of better nutrition rather than external yield increase. High content of protein and major amino acids are very valuable for solving of lack of food production, and the find of genes o₂, fl₂ and bt₂ in corn, hiproly in barley, high lysine of PI 181329 is wheat and erucic acid of Oro or Bronowski in rape are very valuable gene sources for the improvement of protein, amino acids and fat of grain crops. These kind of gene sources, however, are subjected to be solved in upland crops in Korea by introduction of backcross for the major genes, attempt to develop new genetic materials by the mutation breeding and study on ecumulation methods cf minor genes. To make breeding efficiency better the development of generation acceralation techniques are very important. In wheat and rape especially, the germination method of prematured seeds and green plant vernalization, which overcomed the difficulties of winter habit vernalizing and shorttening of ripening periods, are recent big progress. Selection criterion of desired characteristics at different growing stages and finding a reasonable place of summer growing are requied for the increase of number of growing seasons at green house and natural field as a practical utilization.