Nitrogen soil fertilization with

Two weeks after planting in the pipes, the plants were thinned to 35 pipe per pipe each and the cups to one plant each, and the treatments begun. Each first, third and fifth day of the week for twelve weeks the pipes were flushed with three liters of tap water poured in the elbow end. The water flowed past the plant root systems and drained out the screened end of the pipes into a flask. One hundred milliliter aliquots of this water ( root exudate ) were used to water the soybean plants in the cups three times weekly. After each flushing, two liters of a low nitrogen (50 ppm N) complete nutrient solution (Peter s Hydro-sol ) were added to each pipe. The soybean plants in cups were watered as needed at other times with tap water. On alternate weeks the soybean plants were fertilized with the complete nutrient solution. At 4, 8 and 12 weeks after the root exudate treatments started eighty soybean plants (10 treatments x 2 soybean varieties x 4 blocks) were randomly chosen for analysis. The soil was washed free of the plant roots and each soybean plant was divided into roots, nodules, stems, leaves and fruits. The plant parts were dried at 105°C for four days and weighed. 

Russo M, Iacona R, Verde E, Belligno A, Sardo VI (2008) Response of soil, water and plants to fertilization with mineral and organic nitrogen fertilizers. Proceedings of the ASABE confer-... 

Ou et al. [74] reported the enhancement of the degradation of methyl bromide in soil pretreated with an ammonia-based nitrogen fertilizer (i. e., (NH4)2S04) and stimulation of methyl bromide degradation in soil inoculated with a nitrifier, Nitrosomonas europaea. 

What to do Do not overfeed with nitrogen-rich fertilizers. Use a potassium fertilizer if rust is a regular problem. Improve the drainage of soil if necessary. Use a crop rotation. Grow more resistant leek cultivars such as Poristo and Poribleu. Do not overcrowd seedlings. Clear away and compost any diseased plant debris. 

Com, leafy greens and root crops also do well in manured soil. Irish potatoes and sweet potatoes are exceptions. Irish potatoes tend to develop scab and sweet potatoes to crack when fertilized with manure. Peas and beans require httle if ary supplemental nitrogen and do not respond well to manure apphcations. 

In soils of low fertility, fertilization with high-phosphate fertilizer, especially early in the growing season, is recommended to increase yields (Yamaguchi, 1983). A range of fertilization treatments have been recommended for Jerusalem artichoke, although the addition of excessive nitrogen favors top growth at the expense of tuber development. 

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