연초재배기간중(煙草栽培期間中) 증산량(蒸散量) 및 수량(收量) I. 연초생육기간(煙草生育期間)동안의 증산량변화(蒸散量變化)와 토양수분(土壤水分)과의 상호관계(相互關係)

The Interrelationships between Yield, Transpiration of the Tobacco Plant, and Seasonal Meteorological Factors during the Growing Season I. Interrelationship between Change of Soil Moisture and Transpiration during the Growing Season

P.V.C관(管)(직경 40cm)을 이용(利用)한 지하수위조절용(地下水位調節用) 폿트재배(栽培)(지하수위(地下水位) : 30cm 및 100cm)로 연초생육기간(煙草生育期間)동안의 일증산양변화(日蒸散量變化)와 자연강우분포조건(自然降雨分布條件)에서 재배포장(栽培圃場)의 근권토양수분변화(根圈土壤水分變化)를 조사(調査)한 결과(結果) 연초식물(煙草植物)의 증산(蒸散)으로 수분소모양(水分消耗量)이 가장 많은 기간(期間)은 이식후(移植後) 40일(日)에서 60일(日)까지로 전생육기간(全生育期間)동안(70일(日)) 증산(蒸散)된 양(量)의 약(約) 50%를 차지했다. 따라서 재배포장(栽培圃場)의 근권토양수분량(根圈土壤水分量)은 이 기간(期間)동안에 매우 낮은 조건(條件)으로 지속되었다. 또 연초식물(煙草植物)의 증산량(蒸散量)은 기상환경변화(氣象環境變化)에 따라 민감하게 영향을 받아 청명한 날은 흐리고 비오는날보다 약(約) 3배(倍) 많았으며 주간(晝間)의 14:00시(時)부터 16시(時)사이에 최대증산량(最大蒸散量)을 보였고 24:00시(時)부터 08:00시(時)사이에 가장 적은 증산량(蒸散量)을 나타냈다.

Successive changes of transpiration by the tobacco plant during the growing season with pot trial treated with 30cm and 100cm ground water tables were compared with change of soil moisture content in rhizospere of field under natural rainfall conditions. Transpiration from the 41st to the 60th day after transplanting was the highest showing about 50% of total transpiration of whole cultivation period. As the result, soil moisture condition in rhizospere of field was kept insufficiently during the above period. Transpiration by the plant was so remarkably affected by the meteorological environment that the transpiration on rain-cloudy day was one third of that on clear day at middle stage of the growth. Maximum transpiration in a clear day was obtained from 14:00 to 16:00 at the 58th day after transplanting.