초록
이 연구는 장미(Rosa hybrida Hort.) '카디날'에 감마선을 조사하여 얻어진 변이의 발생 양상을 구명하고 변이의 특성을 평가하기 위해 실시하였다. 2002년 44주의 삽목묘에 $^{60}Co$ 선원으로부터 70Gy 선량의 감마선을 처리하여 포장에 심어서 2002년부터 2004년에 걸쳐 화색변이 발생을 관찰하였다. 4가지 화색 돌연변이체를 발견하여 2004년부터 2008년까지 재배하면서 이들 변이체가 완전변이체로 고정된 것을 확인하였다. 각 계통별 삽목.증식한 묘를 2008-2009년까지 농가에서 수경재배하여 특성을 조사하였다. 원래 '카디날'은 화색이 짙은 적색(Red group, 44A, 45B)인데 이로부터 발생한 4가지 변이체들 중, KA1은 연분홍(Red group, 55B-55D), KA2(Fig. 1C)는 분홍색(Red group, 63A-63B), KA3(Fig. 1D)는 KA2와 비슷하나 진분홍색이었고(Red purple group, N57A-N57C), KA4(Fig. 1E)는 주황색(Red group, 43A-43B)이었다. 꽃의 직경에서 원품종 '카디날'은 12.5cm인데 비해 'KA1'은 9.2cm로 작고, KA2는 12.9cm로 커서 서로간에 차이가 있었다. 꽃잎 수는 '카디날'이 35.5장인데 비해 KA2는 39.8장으로 가장 많았고, KA1은 가장 적었다. CIE Lab 값에서 변이체들은 L(명도)은 모두 높아지고 a와 b값은 KA4를 제외하고 낮아진 것으로 나타났다. 신초와 잎의 특성도 원품종 '카디날'과 '카디날'의 4가지 변이체 사이 차이가 있었다. KA1은 신초장, 절간장, 화경장, 가시발생 등에 가장 작았고 나머지 계통들은 대부분 '카디날'과 비슷하였다. 잎의 뒷면의 색은 꽃색이 적색인 '카디날'과 주황색 변이체 'KA4'에서 연한 적색을 띠었으나, KA1, KA2, KA3는 녹색이었다.
This study was carried out to compare the pattern of mutant variation and to evaluate the characteristics of mutants obtained by gamma irradiation in rose 'Kardinal'. Forty four rooted cuttings of 'Kardinal' were irradiated at 70 Gy gamma-ray dose from a $^{60}Co$ source to induce mutants in 2002. The irradiated plants were planted in field, and observed spotting of petal color mutants from 2002 to 2004. Four different kinds of mutant twigs with each different color flower were obtained from the irradiated 'Kardinal' with red petal. After being identified to be a stable mutant from 2004 to 2008, each mutant line propagated by cutting was hydroponic-cultured to evaluate the characteristics in the greenhouse from 2008 to 2009. Four mutant lines obtained from 'Kardinal' with red petal (Red group, 44A, 45B) include KA1 with light pink petal (Red group, 55B-55D), KA2 with pink petal (Red group, 63A-63B), KA3 with deep pink (Red purple, N57A-N57C), and KA4 with orange red (Red group, 43A-43B). Diameters of each flower in four mutant lines were different from 'Kardinal'. The line KA1 was 9.5 cm wide, and it showed the smallest diameter when compared to other mutants. While the line KA2 was the largest one with 12.5 cm 'Kardinal'. Petal number per flower was also variable among the mutants. The line KA2 had 39.8 petals being the largest number among the mutants, while the line KA1 was the lowest one compared to 35.5 petals of 'Kardinal'. Petal color was measured by using colorimeter. Brightness (L) measured at each petal of four mutants increased more than 'Kardinal'. CIE Lab values, a and b decreased more than 'Kardinal' at the petal color of three mutants except the line KA4. Characteristics of shoot, leaf, etc. from four mutants were also different from the ones of 'Kardinal'. The line KA1 was shortest in shoot, node and peduncle length, and lowest in prickle number. The reverse side of leaves was reddish green color in 'Kardinal' as well as the line KA4, but green color in the line KA1, KA2, and KA3.