บทคัดย่องานวิจัย

หมวดหมู่ : ฐานข้อมูลงานวิจัย

Postharvest changes in endogenous cytokinins and cytokinin efficacy in potato tubers in relation to bud endodormancy.

Suttle, J. C.;

Physiologia Plantarum Year: 1998 Vol: 103 Issue: 1 Pages: 59-69 Ref: 41 ref.

1998

บทคัดย่อ

Postharvest changes in endogenous cytokinins and cytokinin efficacy in potato tubers in relation to bud endodormancy.

Using an indirect ELISA, the effects of postharvest storage duration (up to 174 days) and temperature (3 deg C, transferred to 20 deg C for 7 days prior to use) on endogenous cytokinins in potato cv. Russet Burbank seed tuber apical bud tissues in relation to endodormancy status were determined. Following fractionation by HPLC, the following cytokinins were detected: zeatin riboside-5'-monophosphate (ZRMP), zeatin-O-glucoside (ZOG), zeatin (Z), zeatin riboside (ZR), isopentenyl adenosine-5'-monophosphate (IPMP), isopentenyl adenine-9-glucoside (IP-9-G), isopentenyladenine (IP) and isopentenyladenosine (IPA). Regardless of postharvest storage temperature or endodormancy status, IP-9-G was the most abundant cytokinin detected while ZRMP and ZOG were the least abundant. In tubers preincubated at 20 deg C, a growth-promoting temperature, the loss of endodormancy was preceded by significant increases in the endogenous levels of Z, ZR, IPMP and IP-9-G. When stored continuously at 3 deg C, a growth-inh

ibiting temperature, significant increases in ZR, IP-9-G and IP + IPA were observed. The total content of cytokinins increased more than 7 times during postharvest storage as a result of de novo biosynthesis. Dose-response studies using IPA and ZR demonstrated a time-dependent increase in apparent cytokinin sensitivity during postharvest storage. With the exception of IP-9-G, injection of any of these endogenous cytokinins resulted in the rapid and complete termination of tuber endodormancy.