낙엽송은 결실주기가 길고 개화결실이 불량하여 채종원에서 종자를 생산하는데 어려움이 있다. 최근에는 이 문제를 해결하기 위해 다개화클론을 선발하여 채종원을 조성하는 방안이 제기되고 있다. 이에 본 연구에서는 낙엽송 클론의 개화량 변이 조사, 유전모수 추정 및 안정성 분석을 통해 개화결실 특성이 우수한 클론을 선발하고자 수행되었다. 암꽃 개화량 변이는 1980년부터 1984년에 걸쳐 조성된 강원 춘천 소재 낙엽송 클론보존원에서 2003년부터 2005년까지 116개 클론을 대상으로 조사하였다. 연도별 개체목의 개화율은 28.4~67.2%로 연년변이가 큰 젓으로 조사되었으며 개체목 당 평균 암꽃 개화수는 9~176개 범위였다. 클론간의 개화량 차이는 모든 조사연도에서 유의한 차이를 보였으며 개화가 불량한 해일 수록 변이폭이 큰 경향이었다. 암꽃 개화량에 대한 광의의 유전력은 평균 0.52로서 높게 나타나 강한 유전적 조절을 받고 있는 형질인 것으로 추정되었다. 또한 개화량 순위 상위 30%의 클론을 선발했을 때 기대되는 개량효과(%G)는 57.4%로 추정되었다. 평균 암꽃 개화량과 변이계수를 이용하여 클론별 개화량의 안정성을 분석한 결과, 경기9(29), 강원37(137), 충남6(46), 충남14(414)와 일본산 R11, R8 클론이 평균 개화량이 많고 안정성이 높은 것으로 나타났다. 본 연구를 통해 암꽃 개화량이 많은 클론을 선발하여 이용할 수 있는 가능성을 확인할 수 있었지만, 낙엽송의 다개화클론 채종원을 효율적으로 조성하기 위해서는 수꽃 개화특성 조사 및 구과분석 등 추가적인 연구가 뒤따라야 할 것이다.

The standard emission rate(ERs) of isoprene was quantitatively measured in situ from Quercus mongolica Fischer that dominates more than about 85% of domestic oak trees. The ERs values in spring and summer were similar to 64.4 and 58.1 (㎍C/gdw/hr), respectively. The ERs in autumn, 7.06(㎍C/gdw/hr), was about 8～9 times lower than those in spring and summer. The coefficient of determination (r2) between ERs and CL․CT ranged from 0.593 to 0.836. The correlation coefficients between the ERs and PAR, the ER and temperature suggested that ERs have strong correlation with PAR(photosynthetically active radiation) and temperature. In addition, the high values of PAR, temperature, and ERs were found in the time zone of 15:00 ～17:00(spring), 15:00 ～ 16:00(summer), and 14:00 ～ 15:00(autumn).

In order to investigate the compositions and the emission rates of monoterpenes emitted from coniferous trees, those from Larix leptoleis (Sieb. et Zucc.) Gordon were measured. In spring and summer, the major monoterpenes were α-terpinene, α-pinene, myrcene; however, α-pinene and α-terpinene were most abundant in fall. The total mean monoterpene emission rates were 0.455 (㎍C/gdw/hr) during the whole period. The higher monoterpene emission rates were found in fall compared to those in spring and summer. In addition, the slopes (β value) between emission rate and temperature were two times lower in fall than those in spring and summer. It was also found that Larix leptoleis (Sieb. et Zucc.) Gordon had lower monoterpene emission rates than P. densiflora and P. rigida.

The seasonal flower, leaf and fruit color characterlstics of deciduous woody landscape plants were investigated through the field survey in Suwon, Korea from January 1, 1992 toMarch 20, 1993.The results were as follows ;1. There were 12 cases in the combination of leaf spreading, anthesis, deblossom, fruit coloring,fruit falling, fall foliage coloring and leaf falling of deciduous woody landscape plants(163 spe-cies) investigated. And species of the leaf spreading, anthesis, deblossom, fall foliage coloringand leaf falling were 71(43.9%). And species of the leaf spreading, anthesis, deblossom,fruit coloring, fall foliage coloring, leaf falling and fruit falling were 40(24.5% ).2. The total continuing period of the flowering, fall foliage coloring and fruit coloring of decid-uous woody landscape plants(79 species) investigated varied from 2 months to more than 9months. And the species over 3 months below 4 months were 23(29.2%).3. There were 24 cases in the combination of color of flower, fall foliage and fruit of deciduouswoody landscape plants(79 species) investigated. And the species of the white flower, red fall fo-liage and red fruit were 16(20.3% ).