II. 26. New find accordion rachis and its inheritance in barley.
B.H. Lee, Yeongnam Crop Experiment Station, Milyang 605, Gyeongnam, Korea. "R"
We obtained a new barley named by YBG-ACS 1. This barley shaped accordion in rachis type (Fig. 1) and was found in the segregating generation of male sterile facilitated recurrent selection population RSPYB 1 established in Korea (Lee et al. 1980). This type of barley has been reported previously by Halan (Briggs, 1978) and its genetic analysis was made by several workers, respectively (Nilan, 1964). However, the new find YBG-ACS 1 barley was interesting in its several agronomic traits.
Figure 1. Spike and rachis type of barley YBG-ACS 1.
The most striking trait of this barley is unusually long spike length in spite of very short culm length as shown in Table 1. The ratio of spike length to eulm length was 29.4% in YBG-ACS 1 comparing to that of 5.1% in Korean leading variety Oweolbori.
Table 1. Agronomic traits of barley YBG-ACS 1.
This barley, YBG-ACS 1, was crossed with Oweolbori for genetic studies on the rachis and the spike type. In the F2 population of this cross, the segregation of accordion rachis was expressed by the epistasis with the segregating ratio of 13:3 for normal straight rachis to accordion rachis (Table 2).
However, the spike type classified with the rachis internode length was segregated to the ratio of 9:3:3:1 for lax-type:normal-type:accordion-type:compact-type, respectively, that was expressed by control of two independent genes (Table 3).
Table 2. Segregation of barley accordion rachis in F2 population of YBG-ACS 1 and Oweolbori cross.
Table 3. Segregation of barley spike type in F2 population of YBG-ACS 1 and Oweolbori cross.
Based on the above results, the new find YBG-ACS 1 barley was expected to be used as an available genetic stock for the improvement of spike type which normally has compact and short spike to the lax and long spike. To obtain the improved spike type, the progenies of YBG-ACS 1 and Oweolbori cross is under selection in the field.
References:
Briggs, D.E. 1978. Barley, John Wiley and Sons. New York: p. 65-67.
Lee, B.H., D.Y. Suh, H.S. Suh, and R.K. Park. 1980. Studies on male sterile facilitated recurrent selection in barley breeding. I. Development of RSPYB 1 population and selection of pedigree lines. Jour. Korean Soc. Crop Sci. 25(1):39-46.
Nilan, R.A. 1964. The cytology and genetics of barley 1951-1962. Washington
State University, p. 126.
