2000년도에 검정에서 역병에 살아남은 개체들로부터 채종하여 육성한 Capsicum chinense 31계통에 대하여 역병 저항성을 검정한 결과 고도의 저항성을 나타내는 것은 발견되지 않았다. 2001년도의 검정에서 역병에 살아남은 개체로부터 채종한 재래종 26계통에 대하여 다시 역병 저항성 검정을 실시한 결과 KC180, KC230, KC195, KC194에서 다수의 개체가 살아남아 저항성을 나타내었다 그러나 KC180과 KC230은 각각 AC2258과 CM334와 혼종된 것으로 관찰되었다. KC195와 KC194는 재래종의 형질을 유지하고 있는 것으로 관찰되었다. CM334의 보존 증식과정에 자연교잡이 일어난 것으로 보여 이의 순도향상을 위하여 채종년도별로 시료를 꺼내어 역병 저항성 검정을 실시한 결과 가장 오래된 1992년도 채종종자에서부터 약간의 이형주가 관찰되기 시작하여 1995년부터 2001년도까지 시간이 경과함에 따라 많이 변형되어 있는 것을 알 수 있었다. 1992년도 종자에서 이형주를 제거하고 원형의 개체로부터 자식종자를 대량 채종하였다. 함께 공시한 AC2258은 순수한 것으로 확인되었다. 1995년도 채종 CM334 종자에서는 비록 혼종은 되었으나 측지발생이 적은 개체들이 발견되어 이들을 개체 선발하여 역병에 저항성이며 측지발생이 적은 계통으로 육성하고 있다.

sy-2 (Seychelles-2) is a temperature sensitive natural mutant of Capsicum chinense and native to Seychelles Island in Africa. Previously we showed that sy-2 leaves were irregularly shaped and defective in chlorophyll development at temperatures below 24℃. A segregation test revealed that the sy-2 gene is controlled by a single recessive gene. To identify the sy-2 gene, we performed a map-based cloning approach using a total 600 individual F2 plants derived from crossing sy-2 and the wild type C. chinense ‘No.3341’. Fine-mapping of the locus allowed us to position sy-2 to an approximately 170-kb region flanked by markers IN2-1-1 and SNP-3-7 on chromosome 1. Among the approximately 36 hypothetical genes in this region several candidate genes including: HSP90-like ATPase family proteins, lipid-transfer proteins, calmodulin-domain protein kinases, and zinc finger proteins (ZFPs) were identified. RT-PCR and sequencing of the hypothetical genes are under way to identify sy-2.

sy-2 (Seychelles-2) is a temperature sensitive mutant of Capsicum chinense and native to Seychelles Island in Africa. Previously we showed that sy-2 leaves were irregularly shaped and defective in chlorophyll development at temperatures lower than 24℃. A segregation test revealed that the sy-2 gene is controlled by a single recessive gene. To identify the sy-2 gene, we performed a map-based cloning approach using a total of 1,010 F2 plants derived from crossing sy-2 and the wild type C. chinense ‘No.3341’. sy-2 gene is located on chromosome 1, 0.3 cM and 0.1cM away from cosII markers C2_At4g29120 and C2_At1g09070, respectively. The tomato genome sequence between those two markers was compared with pepper genome sequence. We found three of pepper scaffold sequences in this region. We developed seven ingle nucleotide polymorphism (SNP) markers on the pepper scaffold sequences, among which five SNP markers were co-segregated with sy-2. To fill the gap between the scaffolds which contains co-segregating markers, we screened a bacterial artificial chromosome (BAC) library, and end-sequences of total of 22 AC clones were i. We found that five clones were overlapped to cover the gap. We fully sequenced four AC clones and found that the physical distance between C2_At4g29120 and C2_At1g09070 is 343kb. This region contains 70 putative genes such as HSP90-like ATPase family proteins, lipid-transfer proteins, calmodulin-domain protein kinases, and zinc finger proteins (ZFPs). To identify the sy-2 gene, we performed RT-PCR and found that a ZFP-like gene is differentially expressed between WT and sy-2 leaves. This result suggests that the ZFP-like gene is a strong candidate for the sy-2 gene. We are currently characterizing this candidate gene.