자운영 재배농가에 자운영 안정적 입모확보에 기초자료
를 얻고자 자운영 지속재배와 매년파종시 입모 및 생육특성
을 조사한 결과는 다음과 같다.
1. 자운영 지속재배포장에서 가을철 토양 속 자운영 종자
는 이앙전 로타리는 토양표면에서 15 cm깊이까지 고루 분
포한 반면, 부분경운 이앙시는 주로 10 cm깊이 이하에서
대부분 분포하였다.
2. 자운영 지속재배시 출아깊이는 부분경운 이앙시 1~3 cm.
로터리경운 이앙시 1~5 cm에서 출아가 되었다.
3. 자운영 지속재배는 표면에서 출아하는 매년파종 자운영
보다 월동전 뿌리 길이가 깊어 월동율이 높고 논 정지 작업
시 종자가 토양과 고루 혼합이 되어 입모균일도가 10.6~
11.7% 가량 높아 입모수 확보가 유리하였다.
4. 자운영 지속재배시 건물생산성은 수분부족 및 저온 등
기상환경이 불량 할 경우 매년파종보다 건물생산성은 높았
으나 환경조건이 양호할 경우는 크게 차이가 없었다.Seedling establishment, overwintering ability
and dry matter production of Chinese milk vetch (Astragalus
sinicus L. CMV) in natural reseeding practice were compared
with the annual seedling in 2006~2007 and 2007~2008.
In natural reseeding, CMV seeds were distributed up to 15
cm soil depth in autumn after rice harvest and the seeds
generally emerged from soil at less than 5 cm depth while
they all emerged from soil surface in the annual seeding.
It took 7-8 d longer in seedling establishment of the natural
reseeding practice than the annual seeding. Generally, the
natural reseeding practice showed higher seedling stand
than the annual seeding because of high seedling survival
rate. The high seedling survival rate in natural reseeded
plant was attributed to the longer root length than that of
the annual-seeded plant. In annual seeding, most of the
seeds emerged from the soil surface and the root can not
easily penetrate the soil while, in natural reseeding technology,
the seeds incorporated into the soil during land preparation
emerged from the soil at 0 to 5 cm depths, thereby having
longer root length. The long root length contributed to
greater ability to survive even under low temperature and
low soil moisture conditions during winter. The dry matter
production in the natural reseeding practice was also higher
than the annual seeding when the temperature is low and
soil moisture is not sufficient. This result indicates that
natural reseeding technology is more stable and beneficial
in seedling establishment and dry matter production as
compared with the annual seeding especially under unfavorable
environmental condition for CMV growth. This practice
could be encouraged in CMV-rice cropping system in the
southern parts of Korea.