In Different Soils The Accumulation Difference Of Strontium In Corn And Sunflower And Its Effects On Leaf Photosynthesis

In this study, accumulation and distribution of strontium and the effects of stronium on photosynthetic physiological response mechanism between two plants and three types of soils were investigated. Yellow soil, paddy soil, purple soil three Sichuan major soil were treated with 0,0.5,1,5 and 10mmol·kg-1 different concentrations of strontium chloride(SrC l2·6H20), and corn and sunflower were planted in the treated soils. Plant dry weight in Sr2 + content, plant growth and development targets, photosynthetic pigment content, photosynthetic gas exchange parameters, chlorophyll fluorescence parameters, were measured, to understand the ability of three soils enriched corn sunflower plants and photosynthetic physiology strontium leaves. The results showed that:(1) In yellow soil, paddy soil, purple soil, ① at the same level of treatment, corn and sunflower plant aboveground and underground parts enrichment uptake correlated with adding strontium content in the soil, and among some treatment there was a significant difference(p<0.05), may be added strontium strontium significantly enhanced the activity of the soil; ② Enrichment of the whole aboveground> underground part, may be due to the same concentrations of strontium, more active in the transport of stems and leaves. With increasing concentration of strontium, the root of the transport mechanism was the obvious suppressed; ③ In the same concentration, increasing time, corn and sunflower aboveground enrichment factor increased, growing ability of enriching strontium; ④ In one treatment level, sunflower enrichment coefficient 、transfer coefficient was greater than corn, and sunflower was stronger than corn about strontium enrichment capacity.(2) In yellow soil, chlorophyll a content of corn and sunflower was promoted in 0-5 mmol ? kg-1 when inhibited in 10 mmol ? kg-1. The content of chlorophyll b in the experimental setting concentration range was always promoted; About corn, net photosynthetic rate of maize(Pn), intercellular CO2 concentration(C i), transpiration rate(Tr) were promoted in 0-5 mmol ? kg-1, when subjected to suppression in 10 mmol ? kg-1. Stomatal conductance(Gs) in the concentration range of the experimental setting was always promoted; About sunflower, net photosynthetic rate(Pn), intercellular CO2 concentration(C i), stomatal conductance(Gs), transpiration rate(Tr) were promoted in 0-5 mmol ? kg-1, when subjected to suppression in 10 mmol ? kg-1. maximum fluorescence yield of maize leaves(Fm), photosystem Ⅱ maximum quantum yield(Fv / Fm) and photosystem Ⅱ potential activity(Fv / Fo) in the experimental setting range was always promoted, only the initial fluorescence(Fo) in 10 mmol ? kg-1 was suppressed. The four chlorophyll fluorescence parameters of sunflower leaf were restrained in 10 mmol ? kg-1; Root length, biomass within the scope of this experiment was always promoted, plant height in 10 mmol ? kg-1 wsa inhibited.(3) In paddy soil, about corn and sunflower, chlorophyll a, chlorophyll b content, net photosynthetic rate(Pn), stomatal conductance(Gs), intercellular CO2 concentration(Ci), transpiration rate(Tr) maximum fluorescence yield(Fm), PS Ⅱ maximum quantum yield(Fv / Fm) and photosystem Ⅱ potential activity(Fv / Fo) were promoted in 0-5 mmol ? kg-1, when subjected to suppression in 10 mmol ? kg-1; Root length, biomass sunflower within the scope of this experiment were always promoted, plant height in 10 mmol ? kg-1 was inhibited.(4) In purple soil, about corn and sunflower, chlorophyll a, chlorophyll b, corn leaves maximum fluorescence yield(Fm), PS Ⅱ maximum quantum yield(Fv / Fm) and photosystem Ⅱ potential activity(Fv / Fo) were promoted in 0-5 mmol ? kg-1, when subjected to suppression in 10 mmol ? kg-1; Height and biomass of corn in this experiment were always promoted, root length in 10 mmol ? kg-1 was inhibited; Plant height, root length, biomass of sunflower were always promoted within the scope of this experiment.(5) In three soils, corn and sunflower enrichment capability contrasted that at the same concentration of treated, about plants aboveground and underground parts of enrichment: yellow soil> paddy soil> purple soil, and the pH of yellow soil was acidic. It conducived to carbonate hydrolysis, thus there were more effective state strontium content in the soil,enrichment of the underground part of strontium was more big purple soil and paddy soil. And to be more heavy clay soil, with shale and sandstone, mostly calcareous cementation, and pH of purple soil was alkaline(pH = 8.07), resulted that adsorbing and immobilizing strontium in purple soil were more stronger, smaller portions enrichment of above and below ground. In paddy soil corn, sunflower height, biomass are biggest, yellow the smallest. Because growth robust, stiff stems need potassium, and the biggest potassium content is in the soil paddy soil. Yellow soil and purple soil phosphorus, nitrogen content is also less than paddy soil, as the characteristics of the relationship between families and genera in the same process the corn plant height is greater than the sunflower. The most important indicator of photosynthesis Pn, Fv / Fm values are biggest in paddy soil, and soil nitrogen content in paddy soils under the three is the highest, but it happens to be dark green leaves are necessary, most paddy soil fertility well. Corn and sunflower are good growth, so the photosynthesis is the strongest.