| With rapid development of the economy the environmental protection and the treatment of contamination has became a hot topic which caused by the whole society attention. The emission of heavy metal could production severe effect on agriculture production and food safety. Therefore the governance of pollution has become widely problem which attracting people's attention. In Agriculture, Cupper and zinc are required microelements of plant. However, when concentrations are excessive, they could poison plant as well. The series of security of foods questions arising from these urgently demand. The Advance and applied prospect of phytoremediation in heavy metal contamination soil still became important study direction in nowadays. How to reduce heavy metals in polluted soil impact on crops, especially with the regional environmental conditions repairing soil pollution, has become an agricultural research in the field of environmental hot spots.Drought and shortage of water resources are basic environmental problems in northwest China. The unreasonable emissions of industrial pollutants into surface water lead to the agricultural irrigation water pollution and the accumulation of heavy metal pollutants in the farmland, which exacerbated the risk of agricultural production. Therefore study on reused path of heavy metal pollution in soil and fully utilize the soil resource were still an Urgent Issue. However, one of the important pathway increasing resistance is to increase the tolerance of crops. Sulfur is an essential element in crops nutrition, which plays a vital role in crop growth and metabolism. It has been reported that sulfur can stimulate the metabolism of sulfur-containing compounds in crops and also be of importance in photosynthetic pigments synthesis, enzymic activities, protein anabolism and catabolism in plant. Sulfur nutrition regulates the functions of some channel proteins and has a crucial role in the transmembrane transport of water and inorganic nutrient elements. And organic sulfur compounds in the bodies of plants also have obviously efficacy on resist environmental pollutants. Therefore, researches on the impact of sulfur on crop under physiological indicators reveals the great theoretical to study the effects of sulfur on the physiological, and also have important value on the elucidation of the physiological mechanism of plant nutrition and the practical importance in guiding the appropriate water and fertilizer management in dryland farming.In this research, corn and wheat were selected as experiment materials. By different drought and heavy metal treatments, method in different sulfur levels, The adjustive ability of sulfur was studied on Physiological Indicators for crops like: content of chlorophyll, Chlorophyll Fluorescence Kinetics Parameters, the content of MDA, and biomass of crop. The main results were as follows:1. compered with CK, Sulfur nutrition significantly affects the photosynthetic pigments content in leaves of crop seedlings and increased S supply resulted in the increase of chlorophyll. With the concentration of S in the nutrient solution, the chlorophyll content in functional leaves apparently increased. Drought resulted in the decrease of chlorophyll in functional leaves, but which was inhibited with the concentrated S supply in solution. And Sulfur nutrition also have ability to resist the heavy metal stress like Zinc. The concentration of Zinc is 250 mg/L, and water stress is -0.3MPa. The treatment S0 and S1/2 was approach in the change of chlorophyll content. Which with the time of intimidation were both obviously decreased. But the treatment S1 and S2 manifested slowly. It could significant inhibition the decrease of of chlorophyll in functional leaves. From the changes of the biomass, we could see that: With the increase of Sulfur nutrition in the aquasolution experiment. Part of above-ground biomass had manifestation on the trend of gradually increased in the treatment of CK, Zinc and drought stress. S0 and S1/2, different treatment had significant changes in above-ground biomass. It was different in S1 and S2. Show that although sulfur nutrition had some regulation effect in the condition of Zinc and drought stress. But it would has lost adjustment ability under serious environment. S0 and S1/2.Between the two kinds of sulfur concentration, The root of biomass was no significantly difference. The treatment S1 and S2, The root of biomass of CK has slightly decreased.Show that sulfur nutrition supplied has possible improving the root absorbed nutrient and makes more nutrient used to the growth of above-ground. And pairs with heavy metal and drought stress. The sulfur nutrition has effect of promote root growth. Manifested the weight has significant increased plants with resist the damage from environment stress.2. In pot experiment, according to Third Class Farmland Environmental Quality Standard for Soils, 500mg/kg Zn and 400mg/kg Cu were added into the soil. sulfur addition showed a positive role in the restore of chlorophyll in leaves. Drought resulted in the decrease of chlorophyll in functional leaves, but which was inhibited with the concentrated S supply in solution,, The sulfur nutrition has effect of resist the damage from heave metal stress. Under the heave metal Cupper stress. Added sulfur nutrition could be significantly increase the root biomass meanwhile also increase the upper part. Show that sulfur nutrition play an important effect on resist heave metal stress. In addition, It has no distinct effect on heavy metal Zn on Growth of Wheat. And sulfur nutrition could be significantly increase the biomass of over-ground.3. Sulfur nutrition could decrease the content of MDA and showed decline in the response to the removal of drought and heave metal stress. In pot experiment, the influence of drought is quite clear. Effects of Cu, Zn Pollution on the Content of Wheat's MDA was limited. The content of MDA in drought group was significant increased compared with that in heavy metals contaminated. Showed that the heavy metal in soil has been relieved, drought becomes the main influential factor in the pot experiment.4. Sulfur nutrition has significant Effects on chlorophyll fluorescence parameters of wheat seedling under environment stress. In general: Chorophyll fluorescence parameter showed that the Fv/Fm, ETR, qP had a decreasing trend under heave metal and drought stress. They would be rehabilitated after rehydration. The results indicate that Sulfur nutrition has much significance for recover capability after drought stress. The heave metal Cu has increase the chlorophyll fluorescence parameters qN P of wheat seedling blade. The changes qN P showed that the treatment S0, S1/2 Low Sulfur nutrition has weakly Influence to relief the injury ability to excess light energy to the PS II Reaction Center. The efficiency of excitation captured by open PS II centers was enhanced by Added sulfur nutrition. indicated that PS II had higher capacity electronic transfer and heat dissipation and could prevent photosynthetic apparatus from damage by excessive light energy.
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