角倍蚜虫瘿对盐肤木光合特性和总氮含量的影响

通过温室栽培和接种实验,以接种角倍蚜形成虫瘿的盐肤木和未接种角倍蚜的盐肤木为实验材料,测定和分析虫瘿对盐肤木光合特性和不同组织氮含量的影响。结果表明虫瘿对盐肤木的光合作用形成扰动,与对照植株相比较：(1)有虫瘿复叶的最大净光合速率升高,其中虫瘿初期、中期和后期分别升高14.49%、32.17%和42.01%；虫瘿还引起无虫瘿复叶最大净光合速率升高,但中期以后下降到正常水平；(2)虫瘿中期有虫瘿复叶的光饱和点升高、无虫瘿复叶光饱合点下降；虫瘿初期和中期有虫瘿复叶的光补偿点升高、无虫瘿复叶光补偿点下降；(3)虫瘿初期引起有虫瘿复叶及邻近无虫瘿复叶暗呼吸速率升高,但中期和后期影响不显著。虫瘿对盐肤木光合作用的扰动程度与小叶的位置和虫瘿生长时期密切相关。同时,虫瘿改变了盐肤木叶片氮含量分布,其中虫瘿外壁、有虫瘿复叶和无虫瘿复叶的氮含量分别为1.13%、1.98%和2.14%,这可能是营养物质从无虫瘿复叶流向有虫瘿复叶,并最终流向虫瘿,满足虫瘿和瘿内蚜虫生长需求的原因。

Effects of Chinese gallnut on photosynthetic characteristics and total nitrogen content of Rhus chinensis

Chinese gallnut which formed by some aphids is a special local product of China and valued as a commercial product for export. Schlechtendalia chinensis is the main commercial species which induces horned gall on Rhus chinensis and its shares about 75% more Chinese gallnut yield of the world. Effects of horned gall on photosynthetic characteristics and total nitrogen content of R. chinensis were analysed in Kunming, Yunnan province. The result indicated that photosynthetic characteristics of R. chinensis were disturbed by the horned gall. Compared to the control plants, (1) maximum photosynthesis rates (Amax) of the leaves induced gall of treatment plant rose to 14.49%, 32.17%, and 42.01% by horned galls in the initial, middle and late gall stages, respectively. Maximum photosynthesis rates of the nearby leaves without gall were also raised but declined after middle gall stage. (2) light-compensation points (Lcp) of the leaves induced gall were raised, but the Lcp of the leaves without gall were declined in middle gall stages. Light-saturation points (Lsp) of the leaves induced gall were raised, but the Lsp of the leaves without gall were declined in initial and middle gall stages. (3) dark respiration rate (Rd) of the leaves both induced gall and without gall were raised in the initial gall stages, but no significant influences in the middle and late gall stages. Effects of horned gall on photosynthetic characteristics of R. chinensis leaves were correlated to the leaflet positions and the gall growth stages. At the same time, the total nitrogen content distribution of R. chinensis leaves had been changed by the horned gall. Total nitrogen contents of gall, leaves induced gall and leaves without gall were 1.13%, 1.98%, and 2.14%, respectively. It is the possible reasons that nutrition flows to the leaves which induced gall and finally to the galls from leaves without gall, and supplied to the gall and galling aphids need.