新疆南疆盆地2个核桃主栽品种果实不同生育时期光合生理特性

分析比较新疆南疆盆地2个主栽配套核桃(Juglans regia L.)品种的光合特征,以期为南疆盆地核桃栽培管理和良种选育提供科学依据。以新疆南疆盆地‘温185’(J. regia "Wen185")和‘新新2号’(J. regia "Xinxin2")为研究对象,采用LI-6400便携式光合仪和FMS-2脉冲调制式荧光分析仪测量果实不同生育时期的光响应曲线、光合作用参数和叶绿素荧光参数的动态变化,分析其光合生理特性。结果表明：‘温185’核桃LSP在近成熟期最大,‘新新2号’果实在脂化期LSP最大,2个核桃品种Pn均在硬核期时最大；晴天天气条件下,2个核桃品种果实不同生育时期Pn日变化均呈双峰变化趋势,具有明显“光合午休”现象,且“午休”现象的发生伴随着Ci的降低和Ls的升高；2个核桃品种果实不同生育时期均发生光抑制现象,且光抑制发生时伴随着Fo的降低。深入分析可得2个核桃品种的“光合午休”现象是由气孔限制因素引起,且光抑制现象的发生不是由于光系统受到破坏引起,而是由非辐射能耗散引起。

Photosynthetic Physiological Characteristics of Two Main Cultivated Walnut Varieties at Various Phenological Periods of Fruit Development in Southern Xinjiang Basin

The photosynthetic characteristics of two main walnut varieties in southern Xinjiang basin were analyzed and compared, in order to provide scientific basis for the cultivation and breeding of Juglans regia in southern Xinjiang Basin. The J. regia "Wen185" and J. regia "Xinxin2" in the southern Xinjiang basin as the research object, the photosynthetic characteristics, photosynthetic parameters and chlorophyll fluorescence parameters of different growth stages of the fruit were measured by LI-6400 and FMS-2, and analysis the photosynthetic characteristics. Results show the LSP of J. regia "Wen185" is maximum in the near mature stage, The LSP of J. regia "Xinxin2" is maximum in the fatty phase, the Pn of two walnut varieties are the highest in the hard core stage; Sunny weather conditions, the curve of diurnal variation of net photosynthesis rate showed two single peak of two walnut varieties fruit at different growth stages, obvious midday depression of photosynthesis, and the phenomenon of "midday depression" was accompanied with the decrease of Ci and the increase of LS; Photo inhibition occurred of two walnut varieties fruit at different growth stages, and the decrease of Fo is accompanied by photo inhibition. In-depth analysis available that the phenomenon of "midday depression of Photosynthesis" of two walnut cultivars is caused by stomata limitation factors and the occurrence of photo inhibition is not caused by the destruction of optical system, but because of the non radiant energy dissipation.