光質及溫度對白草莓植株生長及果實呈色之影響

Effects of Light Quality and Temperature on Plant Growth and Fruit Color in White Strawberry

白草莓果實表皮呈現白色或淺粉色，果肉為白色，然其易受環境影響，使果實著色不均、不顯白。本試驗以紅光(654 nm)、藍光(453 nm)、紅藍混光(R:B = 7:3)及白光(430-680 nm)等四種光質及日夜溫22/18oC及28/25oC兩種溫度，對三個白草莓品系進行複合處理。處理後，白草莓植株營養生長以紅光處理植株之平均葉柄長最長、葉面積最大，而藍光處理則使葉柄短縮且葉面積較小；高溫環境有利於植株的營養生長。在22/18oC，白草莓果實以紅光處理的果實a*值顯著較低，藍光處理的果實a*值較高。白草莓果實花青素以Cyanidin-3-glucoside與Pelargonidin-3-glucoside為主，在低溫下，光質的差異主要影響Cyanidin-3-glucoside含量，藍光處理會顯著增加Cyanidin-3-glucoside含量，紅光處理則會降低其含量，但在紅果草莓‘豐香’中，光質則主要影響Pelargonidin-3-glucoside含量。白草莓以果色白為其特點，果實發育時以紅光及低溫處理，能使白草莓果實較易維持白果特徵。

White strawberry has white or pink skin color of the fruit, while the color of flesh is white, which is significantly different from the commercial red strawberry. The white strawberry fruit would be excessive-colored and unevenly colored when cultivated open field in Taiwan. Four different light qualities, including red light (654 nm), blue light (453 nm), red-blue light (R:B = 7:3) and white light (430-680 nm) were combined with 22/18oC and 28/25oC of temperature treatments. The vegetative growth of the plant, the petiole length and leaf area with red light treatment were higher than the other treatments; while the blue light treatment shorten the petiole length and reduce the leaf area. The vegetative growth was beneficial to white strawberry as well. The a* value of red light treatment of fruits was significantly low, and the a* value of blur light treatment was the highest. The anthocyanins in white strawberry fruits are mainly cyanidin-3-glucoside and pelargonidin-3-glucoside. At low temperature, the difference of light quality mainly affects the content of cyanidin-3-glucoside. Blue light treatment will significantly increase the content of cyanidin-3-glucoside, while red light treatment will decrease its content. However, in the red strawberry ‘Toyonoka’, light quality mainly affected the content of pelargonidin-3-glucoside. As white strawberry is characterized by white its fruit color, using red light and low temperature treatment may maintain the fruit characteristics of white peel color of the white strawberry.