field experiments were conducted at the rice research institute (mazandaran province) using randomized complete block designs in two fields of different levels of organic carbon (low and medium) during two cropping years. the treatments were repeated in three replicates and while seven nitrogen levels (urea-n input) 0, 23, 46, 69, 92, 115 and 138 kg n per ha employed. results indicated that opt...

in many crops, incorrect management of nitrogen and water is one of the most important factors in the resources productivity such as water and nitrogen. in order to evaluate the effects of different nitrogen levels (zero, 50, 100 and 150 kg ha-1) and irrigation application rates (100, 75 and 50% of water requirement per species) on corn, sesame and sugar beet, three separate experiments was con...

Abstract In pasture-based dairy production systems, identifying the appropriate stocking rate (SR; cows/ha) based on farm grass growth is a key strategic decision for driving overall business. This paper investigates number of scenarios examining effects SR (2–3 cows/ha (0.25 unit changes)), annual nitrogen (N) fertilizer application rates (0–300 kg N/ha (50 kg/ha soil type (heavy and free-drai...

A 2-year field study was carried out to find out the effect of three macro nutrients NPK on the severity of Alternaria leaf blight and yield of mustard. Nitrogen @ 80, 100, 120, 140, and 160, phosphorus @ 15, 30, and 45, and potassium @ 30, 60, and 90 kg/ha were applied. Among the nutrients, 120-3060 kg NPK/ha was considered as recommended dose on the basis of soil test. Fertilizer dose 120-30-...

improve forage quantity and quality using organic and biological fertilizers production of important needs in dryland farming systems of the country. in this study the effects of foliar application of four different combinations of amino acid four different time steps were germinated plant growth, stem elongation, flowering and spraying all three steps above with the control treatment was carri...

It is unclear how or even if phosphorus (P) input alters the influence of nitrogen (N) deposition in a forest. In theory, nutrients in leaves and twigs differing in age may show different responses to elevated nutrient input. To test this possibility, we selected Chinese fir (Cunninghamia lanceolata) for a series of N and P addition experiments using treatments of +N1 - P (50 kg N ha(-1) year(-...

A field experiment was conducted for two consecutive seasons (2009/10 and 2010/11) in the Demonstration Farm of the Faculty of Agriculture at Shambat-Sudan, to study the interactive effect of nitrogen fertilization and rhizobium inoculation on nodulation and yield of soybean (Glycine max [L.] Merrill) plants. The experiment was laid out in a randomized complete block design with four replicatio...