Differential Physio-Biochemical Responses to Cold Stress of Cold-Tolerant and Non-Tolerant Grapes (Vitis L.) from China

There are many grape species exhibiting differences in cold tolerance in China. 'Zuoshan1' (Vitis amurensis Rupr. cv. Zuoshan1), one kind of the most cold tolerant grapes, can endure -40 to -50 degrees C, whereas, 'Maoputao' (Vitis quinqanguoari Rehd. cv. Maoputao) is sensitive to the cold stress. To understand the physiological mechanism, we investigated responses of both species to a range of decreasing temperatures under the controlled condition. The cold-tolerant 'Zuoshan1' showed higher accumulation of abscisic acid than non-tolerant 'Maoputao', which was correlated with a more dramatic increase in solutes including sugars, proteins at early stage of our detection. At latter stages, these solutes showed more decline in 'Zuoshan1'. Meanwhile, earlier leaf yellowing and necrosis of 'Zuoshan1' were detected with concomitant decrease in the chlorophyll (Chl) content along with remarkable increase in electrolyte leakage and malondialdehyde, which indicated that the earlier leaf senescence occurred to 'Zuoshan1'. Based on the leaf morphology and parameter investigation, it was concluded that cold-tolerant grape 'Zuoshan1' made quicker responses to the low temperature (LT), indicating it sensed the cold-signal more strongly than the non-tolerant grape 'Maoputao'. Therefore the ability to take more active response to cold stress contributes to the higher tolerance in 'Zuoshan1'.