Photosynthetic Characteristics of Potato in Guizhou Climate Condition

To obtain physiological parameters for potato cultivation,a pot experiment was conducted to study the effects of potato variety and leaf position in high yield growth vigor.The results showed that change of photosynthetic characteristics of potato varieties with different ripe stage was similar.Photosynthetic rate of upper new blades was the highest,that of bottom blades was low.Pn of horizontally placed blades was higher than that in natural state.The diurnal variation of Pn all had midday depression phenomenon.The curves of diurnal variation of Pn and Tr showed two single peaks.Leaf intercellular CO2 concentration showed a "W" shape change.The respiratory rate of Favorita was higher than Hui-2,Pn and daily mean value of intercellular CO2 concentration of Hui-2 were higher than Favorita.