eprintid: 8166 rev_number: 12 eprint_status: archive userid: 17 dir: disk0/00/00/81/66 datestamp: 2014-07-08 05:41:58 lastmod: 2014-07-08 05:41:58 status_changed: 2014-07-08 05:41:58 type: article metadata_visibility: show contact_email: Library-ICRISAT@CGIAR.ORG creators_name: Ssali, H icrisatcreators_name: Ssali, H affiliation: SADCC/ICRISAT(Bulawayo) country: Zimbabwe title: Initial and residual effects of nitrogen fertilizers on grain yield of a maize/bean intercrop grown on a Humic Nitosol and the fate and efficiency of the applied nitrogen ispublished: pub subjects: s2.4 subjects: s2.5 full_text_status: restricted keywords: Calcium ammonium nitrate (CAN), urea, urea supergranules (USG), nitrogen balance, 15N studies, nitrogen placement, nitrogen efficiency abstract: Initial and residual effects of nitrogen (N) fertilizers on grain yield of a maize/bean intercrop grown on a deep, well-drained Humic Nitosol (66% clay, 3% organic carbon) were evaluated. Enriched (15N) N fertilizer was used to study the fate of applied N in two seasons: using urea (banded) at 50 kg N ha−1 in one season, and15N-enriched urea (banded), calcium ammonium nitrate (CAN, banded), and urea supergranules (USG, point placement) were applied in the other season (different field) at 100 kg N ha−1. Nitrogen fertilizer significantly (P = 0.05) increased equivalent maize grain yield in each season of application with no significant differences between N sources, i.e., urea, CAN, and USG. Profitmaximizing rates ranged from 75 to 97 kg N ha−1 and value: cost ratios ranged from 3.0 to 4.8. Urea gave the highest value: cost ratio in each season. Most (lowest measurement 81%) of the applied N was accounted for by analyzing the soil (to 150 cm depth) and plant material. Measurements for urea, CAN, and USG were not significantly different. The high N measurements suggest low losses of applied N fertilizer under the conditions of the study. Maize plant recovery ranged from 35 to 55%; most of this N (51–65%) was in the grain. Bean plant recovery ranged from 8 to 20%. About 34–43% of the applied N fertilizer remained in the soil, and most of it (about 70%) was within the top soil layer (0–30 cm). However, there were no significant equivalent maize grain increases in seasons following N application indicating no beneficial residual effect of the applied fertilizers date: 1990 date_type: published publication: Fertilizer Research volume: 23 number: 2 publisher: Kluwer Academic Publishers pagerange: 63-72 refereed: TRUE issn: 0167-1731 official_url: http://dx.doi.org/10.1007/BF01063332 related_url_url: http://scholar.google.co.in/scholar?as_q=Initial+and+residual+effects+of+nitrogen+fertilizers+on+grain+yield+of+a+maize%2Fbean+intercrop+grown+on+a+Humic+Nitosol+and+the+fate+and+efficiency+of+the+applied+nitrogen++&as_epq=&as_oq=&as_eq=&as_occt=title&as_ related_url_type: pub funders: IFDC citation: Ssali, H (1990) Initial and residual effects of nitrogen fertilizers on grain yield of a maize/bean intercrop grown on a Humic Nitosol and the fate and efficiency of the applied nitrogen. Fertilizer Research, 23 (2). pp. 63-72. ISSN 0167-1731 document_url: http://oar.icrisat.org/8166/1/FertRes_23_63-72_1990..pdf