The Two Kinds Of Waxy Corns, Caijing 868 And Zijing 66, Were Adapted To Low Nitrogen And Phosphorus Nutrient Stress And Their Mechanisms

Eutrophication of rivers and lakes is a hot topic all over the world,and it is still a difficulty in water pollution control.there are many causes of water eutrophication,such as centralized discharge of industrial wastewater and domestic sewage,overuse and spread of agricultural fertilizer.Therefore,we need to control the water eutrophication for improving water quality.In the past,the point pollution source was the research emphasis,but the water quality became worse.So,researchers focus their attentions to controll and management of the agricultural non-point source pollution.In addition to reducing the consumption of nitrogen or phosphorus fertilizer from the sources,the use of plants which have the tolerance to low nutrient stress can also effectively control the agricultural non-point source pollution problem.In my experiment mainly compare the tolerance to low nutrition in Colorized of glutinous maize 868 and Purple of glutinous maize 66and study the effects of low nutrition on two kinds of waxy corm's morphology,physiological and biochemical.Following conclusions be drawn by experimental research and data analysis:(1)With the addition of low nitrogen and phosphorus stress,the dry weight of 868 was increased and then decreased,but 66 was always decreased.Nitrogen and phosphorus stress conditions all made the root length and root activity of the 868 and 66 bring down,but the root shoot ratio and lateral root number increased.With the addition of low nitrogen and phosphorus stress,the root activity of 66 increased and then decreased.the effect of morphological indexes,the root activity in 868 by low nutrient stress were significantly lower than 66.(2)With the addition of low nitrogen and phosphorus stress,malondialdehyde(MDA)and proline(Pro)increased,while soluble sugar(SS)decreased.the effect of Soluble sugar(SS)in 66 by low nutrient stress were significantly lower than 868.(3)With the addition of low nitrogen and phosphorus stress,catalase(CAT)and superoxide dismutase(SOD)activities increased.When nitrogen or phosphorus remained constant and the phosphorus or nitrogen decreased,the peroxidase activities of 868 increased and then decreased,and the peroxidase activities of 66 increased.the effect of peroxidase(POD)and superoxide dismutase(SOD)activities in 868 by low nutrient stress were significantly lower than 66.(4)The activities of acid phosphatase(APase)in leaves of 868 and 66 were improved with the increase of low N and P stress.The effect of phosphorus deficiency was higher than nitrogen deficiency in acid phosphatase(APase)activities.The activities of nitrate reductase(NR)in leaves of 868 and 66 decreased with the increase of low nitrogen and phosphorus stress,and the effect of low nitrogen stress on nitrate reductase activities was much higher than that of low phosphorus stress.the effect of acid phosphatase(APase)and nitrate reductase(NR)activitiy in 868 by low nutrient stress were significantly higher than 66.(5)The chlorophyll(SPAD)content of maize 868 and 66 was decreased with the decrease of phosphorus or nitrogen content,and the effect of nitrogen deficiency on chlorophyll content was higher than phosphorus deficiency.the effect of chlorophyll(SPAD)content in 868 by low nutrient stress was significantly lower than 66.(6)The transpiration rate(E),stomatal conductance(Gs)and net photosynthetic rate(Pn)of 868 and66 were decreased with the decrease of phosphorus or nitrogen,and the effect of nitrogen deficiency on photosynthetic parameters was greater than that of phosphorus deficiency.The transpiration rate(E)and net photosynthetic rate(Pn)of 868 were affected by low stress was lower than 66,but the transpiration rate(E)of 868 were affected by stress was higher than 66.