Breeding Cytoplasmic Male Sterile Lines Resistant to Phytophthora capsici and Ralstonia solanacearum in Capsicum Pepper

역병-풋마름병 복합저항성 세포질웅성불임계 고추 육성

Selection procedures for breeding lines resistant to both bacterial wilt caused by Ralstonia solanacearum and Phytophthora blight caused by P. capsici were executed to generations from $F_2$ and $BC_1F_1$ to $F_4$ and $BC_1F_3$ of crosses between a Phytophthora resistant breed, 'Chilbok No. 1' and bacterial wilt resistant accessions introduced from Vietnam during 2009 and 2010. The breeding populations or lines were tested for resistance to P. capsici and resistant plants were selected. The resistant selections were inoculated with R. solanacearum to discard susceptible plants. Resistance to P. capsici was conspicuously improved by selection from $F_2$ and $BC_1F_1$ and the final selections showed a similar level of resistance to P. capsici as a commercial Phytophthora resistant cultivar, Muhanjilju. A few $BC_1F_2$ selections were crossed to a cytoplasmic male sterile line, Chilbok-A, to identify their nuclear genotype interacting with male sterile cytoplasm. Majority of them was fixed to maintainer (Nrfrf) and only two resulted segregating into male sterile and male fertile plants indicating that the pollen parents were heterozygous in the fertility-restoring gene.

칠성초에 역병 저항성을 도입한 칠복1호에 베트남 도입 풋마름병 저항성 계통을 교배하여 육성한 $F_2$ 및 $BC_1F_1$에서부터 $F_4$ 및 $BC_1F_3$까지 역병-풋마름병 복합 저항성 선발을 2009년도와 2010년도에 걸쳐 수행하였다. 매 세대 역병을 접종하여 저항성을 평가하여 선발하고 선발개체에 풋마름병을 접종하여 감염되는 개체는 도태하였다. 역병에 대한 저항성은 선발과 함께 현저히 향상되었으며, 선발계통들은 역병 저항성으로 판매되고 있는 교배종 '무한질주'와 비슷한 수준의 저항성을 나타내었다. $BC_1F_2$ 선발개체를 칠복CMS-A라인에 교배를 하여 $F_1$의 임성을 보고 화분친의 CMS-Rf유전자형을 검정하였다. 대부분Nrfrf로 고정되고, 칠복 ${\times}$ KC995, 칠복 ${\times}$ KC1009 조합의 일부 개체가 이형(heterozygote) 상태인 것으로 확인되었다.