セル苗育苗におけるセル容量および移植時苗齢がキンギョソウの移植後の生長と開花ならびにストックの移植後の初期生長に及ぼす影響

Effects of Cell Volume and Transplant Age in Cell Flat on Growth and Flowering after Transplanting in Antirrhinum majus L.cv.Mangetsu and initial growth after transplanting in Matthiola incana R.Br.cv.White Dorse were studied.Seeds were sownin flats of two cell sizes (cylinders,448 and 220;volume6,12ml,respectively).At the same time each species were directly sown into wooden containers(38880ml). The plants in cells were transplanted 32,37,42,47,52days old after sowing in A.majus and 18,25,32,39days old in M.incana. The plants having formed root-balls could be found at 42 days and 47days after sowing in cell volume of 6ml and 12ml respectively in A.majus.,and at 25days and 32days after sowing in cell volume of 6ml and 12ml respectively in M.incana.In both species shoot dry weight,root dry weight,stem length,node number and total leaf area were increaced with increaces in cell volume or transplant age.In A.majus flowering was delayed with increases in transplant age,especially in cell volume of 6ml.Cut flower quality suffered markedly with increaces in transplant age. Node number was affected by cell volume but not by transplant age.In M.incana the growth 4weeks after transplanting of plants grown for 25days in cell volume of 12ml showed little difference compared with that of plants grown in the wooden container. The results showed that for cell transplant production in both species,transplanting before 10days formde root-balls using cell volume of 12ml was optimal.Our investigation suggests that the suitable transplant age for work efficiency of transplanting may differ considerably from that for plant growth in both species.

促成栽培したイチゴ’女峰’の’成り疲れ’と同時に発生する受精不良による奇形果発生要因を明らかにするため、イチゴ生産者の15棟のビニルハウスの花粉稔性の変化を調査し、気象要因、葉中無機養分および炭水化物濃度との関係について解析した。花粉稔性は、気温、日射量が低下し、着果負担が増大する1,2月に急激に低下したことから、奇形果発生の原因が花粉稔性の低下にあることが示された。花粉稔性と開花前1～3日の日射量、当日の戸外の最低気温、葉中炭水化物濃度との間に高い相関が認められなかった。CO2施肥によって腋果房収穫開始期（1月）の花粉稔性が高まったことから、低日射と過重な着果負担による光合成産物不足が花粉稔性低下の大きな原因であると考えられた。