Effects Of Adding Exogenous Iron And Boron To Compound Fertilizer On Availability And Biological Effects

Compound Iron Fertilizers had significant effects on rectifying peanuts chlorosis caused by iron deficiency. Pot experiments were conducted in this research to reveal the transformation and iron provision mechanisms of Compound Iron Fertilizers in calcareous soil, and thus to optimize its components and improve its availability and utilization efficiency.Systemic researches were also conducted to evaluate the iron provision mechanisms,transformation and bioavailability capacity of several iron fertilizers.In order to reveal biologic effects of interaction of boron and phosphrous, potted cole experiments were adopted to study the growth of cole under different Compound Boron Fertilizers. Main results were as followed:1. Inorganic additives could diminish effective nutrients of Compound Fertilizers in the course of manufacturing.For Compound Fertilizers demanding to keep the nitrogen content, calcium carbonate powders as additives should be carefully avoided. The content of nitrogen using calcium carbonate powder as its additives could be reduced by 0.5%. Bentonite and calcium carbonate powders had seldom effect on the available phosphorous in Compound Fertilizers. light red bentonite evidently reduced the content of available potassium by 0.37%. In conclusion, Bentonite was applicable to Compound Fertilizers needing to keep the nitrogen content, in contrast, calcium carbonate powder applied to those needing to keep content of available potassium.2. Compound Iron Fertilizers could improve the growth of peanuts significantly. Compared with other treatments, plants fertilized CIF1-H (1.30-0.975-0.975-0.6825) was better in agronomic characters. Accordingly, CIF1 and CIF2 could effectively increase number of branches, and CIF1 was much better. Moreover, CIF1 and CIF2 could reduce percent of peanut etiolated leaves.3. After the application of Compound Iron Fertilizer, active iron content in new leaves of peanuts could be increased significantly, thus enhancing the synthesizing of chlorophyll. The content of chlorophyll in new leaves retained at a higher level and the product of photosynthesis was increased. As a result, the plants were guaranteed a fast growth and increased yields. The correlation between chlorophyll and active iron content was positive, and it could be simulated by the formulation y=ax+b (a≠0), and the correlative coefficient was 0.9416**.4. Fertilizing Compound Iron Fertilizers could raise the accumulation of dry matter in peanuts significantly.The accumulation of dry matter with CIF1-H(1.30-0.975-0.975-0.6825) treatment was the largest.The accumulated velocity showed the tendency to increase at the beginning and then decrease in the following period. Therefore, CIF1 could promote iron transportation toward above-ground part and increase the yield of peanuts. The content of total iron couldn't completely reflect the provision condition of iron. In the high iron level, the total iron in root in treatments CIF3-H, CIF2-H, CK was higher, while the above-ground part was lower. In addition, pH value of soil solution was markedly different in various iron treatments. After the application of CIF1 and CIF2 to soil, pH value of soil decreased.The effects of CIF1-H(1.30-0.975-0.975-0.6825) was significant.And the available iron content in the soil was higher.5. The addition of iron into soils such as DTPA-Fe and EDDHA-Fe increased the iron content of different forms, and the capacity to provide iron was better than FeSO4. There was significantly negative correlation between DTPA-Fe content in soil solutions and pH. The correlation between DTPA-Fe and Exch-Fe was significantly positive. Though the coefficients of DTPA-Fe and other forms of iron such as Carb-Fe and MnOX-Fe were smaller, the correlations were high. In addition, there was positive correlation between Exch-Fe, MnOX-Fe and Carb-Fe. In contrast, the correlations between iron such as Exch-Fe, Carb-Fe and MnOX-Fe and pH value were significantly negative.6. Boron could optimize the growth of cole. Under the level of CBF (20-10-20-0.3)6g·pot-1, the cole grew better. Chlorophyll content was high. The number of leaves, leaf area also increased significantly. Besides, ratio of R/S was largest. Under the level of CBF (20-10-20-0.5)6g·pot-1, the content of Vc was 46.33mg·kg-1. And its weight of plant was largest.Under the level of CBF(20-10-20-0.1)6g·pot-1, ratio of Sugar /Acidity was the largest, and its quality was also better.7. Phosphorus promoted the absorption of boron. When there was great scarcity of phosphorus and boron, the content of available boron in plants reduced with the increment of the phosphorus. With application of the same amount of boron, the available phosphorus and the content of available boron under the high phosphorus level were higher than that of low level.