不同品種油菜對淹水影響光合作用速率、碳水化合物累積及植株受損程度之差異

Cultivar Differences in the Effect of Waterlogging on Photosynthetic rate, Carbohydrate Accumulation, and Plant Injury in Rapes (Brassica rapa L.)

本試驗以四個品種之油菜種植於網室中，施以兩天淹水後排水。‘夏霸王’和‘夏樂天’油菜淹水後葉片之垂葉率及黃化率低，植株無死亡，於排水六天後鮮重僅較對照組減少16.4%-18.5%，且植株生長復原情況佳；故視為耐淹水品種。‘福祿甜’和'さおり'品種受淹水影響嚴重，鮮重減少26.5%-33.9%，且死亡率高，於排水六天後未見恢復正常生長；故視為不耐淹水品種。‘夏霸王’和‘夏樂天’於淹水下植株之光合作用速率減少10%-16.7%，而‘福祿甜’和'さおり'兩品種則減少94%。淹水逆境同時減少不耐淹水品種的光合作用、蒸散作用及氣孔導度。排水二天後耐淹水品種之全可溶性糖濃度顯著高於不耐淹水品種。'さおり'品種於排水六天後有澱粉含量增加現象。 Four cultivars of rape were planted in a net house, subjected to 2 days of waterlogging and then drained. All 'His-ba-wang' and 'His-le-tian' rapes survived the waterlogging with low rate wilting and leaf yellowing, and had fresh weights of only 16.4%-18.5% less than the control plants. Waterlogged plants recovered in 6 days after drainage. Therefore, they were classified as waterlogging-tolerant cultivars. The fresh weights of waterlogged 'Fu-lu-tian' and 'Sa-ou-li' rapes were 26.5%-33.9% lower than the control plants. Waterlogging, also caused high rates of plant death; and the survived plants did not recover normal growth 6 days after drainage. Therefore, these two cultivars were classified as waterlogging-susceptible cultivars. Waterlogging caused the photosynthetic rate reduction by 10%-16.7% for 'His-ba-wang' and 'His-le-tian' rapes but by 94% for 'Fu-lu-tian' and 'Sa-ou-li' rapes. Waterlogging reduced not only the photosynthetic rate, but also the transpiration and stomatal conductance in waterlogging-susceptible cultivars. The total soluble sugar concentration in waterlogging- tolerant cultivars were significantly higher than those in waterloggingsusceptible cultivars measured two days after drainage. The starch concentration of 'Sa-ou-li' rape increased six days after drainage.