Response to added nitrogen of a continuous potato sequence as related to sand thickness over clay

Abstract

Cambouris, A. N., Zebarth, B. J., Nolin, M. C. and Laverdière, M. R. 2007. Response to added nitrogen of a continuous potato sequence as related to sand thickness over clay. Can. J. Plant Sci. 87: 829-839. This study evaluated the effect of rate and timing of N fertilizer application on tuber yield, tuber size distribution and tuber specific gravity of potato (Solanum tuberosum L.) in two sites in a commercial field in 1999-2001. One trial was established at each of the two sites chosen to represent two management zones (MZ) previously delineated by soil electrical conductivity, and differing in soil water availability, as controlled by depth to a clayey substratum. Each trial had 21 treatments including five rates of ammonium nitrate (0-200 kg N ha -1 in 1999; 0-240 kg N ha -1 in 2000 and 2001), each applied according to five application timings (100, 75, 50, 25 or 0% of N applied at planting with the remainder applied at hilling). Increasing N rate increased total and marketable tuber yields in both sites. The N rates required to optimize economic return ranged from 167 to 239 kg ha -1 among years and between sites. Nitrogen fertilizer applied all at planting or all at hilling decreased tuber yields in both sites compared with split N application. The percentage of N rate applied at planting to achieve the maximum marketable tuber yield varied among years from 34 to 61% and allowed a yield increase of 2 to 20%. The proportion of large tubers was higher in the site with a greater depth to the clayey substratum (DMZ site) than in the site with a shallower depth to the clayey substratum (SMZ site). Tuber yield and tuber N uptake were higher in the SMZ site than in the DMZ site when no fertilizer N was applied, and tuber yield was more responsive to fertilizer N rate in the DMZ site than in the SMZ site in one year; however, these differences are not sufficient to justify different fertilizer N management for the two sites. The two sites frequently differed in terms of tuber yield, tuber size and specific gravity, which are important parameters in determining tuber processing quality but the optimal N rate and N timing were similar. These differences may be sufficiently large to justify different potato management practices (e.g., nutrient management, seedpiece spacing) to optimize potato production for the chip processing market. , chacune appliquée selon cinq modes de fractionnement (100, 75, 50, 25 ou 0% de N appliqué à la plantation et le reste au buttage). L'augmentation de la dose de N augmentait le rendement total et commercialisable dans les deux sites. La dose de N requise pour optimiser le retour économique est étendue de 167 à 239 kg N ha -1 dépendamment de l'année et des sites. L'application de la totalité des fertilisants azotés à la plantation ou au buttage diminue les rendements en tubercules dans les deux sites comparée avec une application fractionnée. Le pourcentage de la dose de N appliqué à la plantation pour attendre le rendement commercialisable maximum varie de 34 à 61% dépendamment de l'ann...

Apparent fertilizer nitrogen recovery and residual soil nitrate under continuous potato cropping: Effect of N fertilization rate and timing

“…The locations are referred to as the SMZ and DMZ sites. Soil properties, cropping history, yield and tuber size distribution for each site for 1999 to 2001 were reported previously (Cambouris et al 2007). This study will report on the N rec , RSN and SWN in the same trials.…”

“…The N rates for 2000 and 2001 were increased comparatively to those used in 1999 to identify more easily the N rate which led to maximum yield. Applications of fertilizer N rates at planting and at hilling are described in detail by Cambouris et al (2007).…”

“…Cambouris et al (2006) used apparent soil electrical conductivity within a commercial potato field to delineate two management zones (MZ), which differed in terms of water-holding capacity, soil drainage and soil texture. Moreover, the two sites chosen to be representative of these two MZ showed differences in terms of average tuber yield (Cambouris et al 2006), tuber size distribution and tuber specific gravity (Cambouris et al 2007). These differences may be sufficiently large to justify different potato management practices (e.g., nutrient management, seedpiece spacing) to optimize potato production for the chip processing market (Cambouris et al 2007).…”

“…The objective of the present study was to evaluate the effect of rate and timing of fertilizer N applications on the N rec , RSN at harvest and SWN measured from suction lysimeters at two sites chosen to be representative of these two MZ as described by Cambouris et al (2007).…”

Effect of split application of fertilizer nitrogen on N2O emissions from potatoes

“…The current N fertilization practice used in potato production in Atlantic Canada is to band all fertilizer N at planting. The potential to improve efficiency of nitrogen management in potato production through reduced fertilizer N rates (Cambouris et al 2007) and split fertilizer N application (Errebhi et al 1998) has been identified. Increased fertilizer N application commonly increases N 2 O emissions (Ruser et al 1998(Ruser et al , 2001Smith et al 1998a), particularly when applied at rates that exceed crop N requirement (McSwiney and Robertson 2005;Zebarth et al 2007).…”