Effect of dicyandiamide on growth and nutrient uptake of cotton

Abstract

The nitrification inhibitor dicyandiamide (DCD) offers potential for improving efficiency of Ν applications to cotton grown on sandy soils of the southeastern Coastal Plain. Research has indicated that cotton is sensitive to DCD. The purpose of this greenhouse experiment was to investigate the effect of DCD on growth and nutrient uptake of DPL 90 cotton grown for 73 days in pots containing a typical Coastal Plain soil (Norfolk sandy loam, Typic Paleudult). Nitrogen (50 mg kg -1 ) as NaNO 3 or urea, and DCD (0, 2.5, 5, 10, 15 and 20 mg ITU Downloaded by [University of Toronto Libraries] at 02:36 26 December 2014 2092 REEVES AND TOUCHTON kg -1 ) were applied to the soil at first true leaf and plants were harvested 58 days later. Sodium nitrate increased leaf dry weight and total dry weight of plants 9.1 and 6.0%, respectively, over urea fertilized plants. Leaf area, dryweight, and stem dry weight were reduced linearly with DCD. Fertilization with urea increased concentrations of leaf Ρ, Κ, and Mn and reduced the concentration of Mg in leaf tissue. Dicyandiamide increased leaf N, P, and Κ concentrations but reduced concentrations of Ca, Mg, and Mn. Uptake rates (µg -1 g -1fresh root day -1 ) of Ca and Mg were increased 7.5 and 13.7%, respectively, with NaNO 3 vs. urea, while Ρ uptake rate was 15.5% greater for urea-fertilized plants vs. NaNO 3 -fertilized plants.Dicyandiamide reduced Ca and Mg uptake rates. Phosphorus uptake rates were increased by DCD when urea was the Ν source. The effects of DCD on cotton growth and nutrient uptake generally resulted from the compound itself and were not an indirect result of nitrification inhibition. Although significant reductions in plant growth did not occur unless DCD exceeded that normally applied with recommended Ν rates on this soil, these results suggest a need for caution when applying DCD to cotton grown on sandy soils. INTRODUCTIONSplit applications of Ν are generally used to improve Ν use efficiency of cotton grown on sandy soils of the southeastern Coastal Plain. The use of nitrification inhibitors, such as dicyandiamide (DCD), with Ν applied at or near planting might preclude the need for split applications of Ν on these soils. Dicyandiamide is an effective nitrification inhibitor (1,2) that has been shown to increase yields of winter wheat (2,3) and grain sorghum (4). Greenhouse tests involving DCD applications to cotton indicate that cotton is sensitive to DCD (5,6). Field experiments on a Norfolk sandy loam (fine-loamy, siliceous.

Improving Nitrogen Fertilizer Use Efficiency in Surface‐ and Overhead Sprinkler‐Irrigated Cotton in the Desert Southwest

“…The use of DCD and NBPT addition to UAN compared to UAN alone, like many previous studies, showed no yield benefit (Kawakami et al, 2012;Watts et al, 2014), similar to the null effect with other EFFs (Freney et al, 1993;Rochester et al, 1996;Reeves and Touchton, 1989). There was a yield and N uptake reduction with Agrotain Plus under the sprinkler in 2015 ( Table 7).…”

Nitrogen Assimilation and Growth of Cotton Seedlings under NaCl Salinity and in Response to Urea Application with NBPT and DCD

“…On the other hand, no evidence of plant phytotoxicity was observed by the addition of NBPT and DCD in any of the salinity treatments. Reeves and Touchton (1989) observed that under salinity stress, cotton exhibited sensitivity to toxic effects of DCD, but in our experiment, phytotoxicity did not appear to be a concern.…”

“…Under the aforementioned scenario, increased N uptake does not necessarily have a positive outcome if plants accumulate toxic levels of without incorporating that N into amino acids. Toxic effects of DCD in cotton under high salinity have been observed (Reeves and Touchton ), and to our knowledge, studies on the performance of NBPT in cotton under salinity have not been documented.…”

Effects of new coated release fertilizer on the growth of maize

“…and larger values of Fv/Fm indicate the higher energy capture efficiency of PSⅡ reaction center (Xu et al 2002); the higher level of ΦPSⅡindicates the strong electron transport ability of the photosynthetic apparatus and the larger proportion of absorbed light energy to be used for photochemical reaction (Genty et al 1989) The results of this study showed that, almost all kinds of agronomic characters of maize were in a trend of FCRF3>FCRF2>FCRF1>CRF>CCF>CK (Table 3 and Samiullah et al 1996). Application of DCD is a nitrification inhibitor and the promoting effect on growth of crop has been reported (Arshad et al 1999;Reeves and Touchton 1989). Moreover, fertilization can improve crude fat, protein, soluble sugar, and decrease NO 3 --N content in different degree (Table 5), which was similar to the agronomic characters (Table 5).…”