Development of rapid screening technique for high nitrogen use efficiency under normal and drought environment for corn
2008
Ocampo, A.M. | Ocampo, E.T.M. | Agtarap, M.L. | Descalsota, J.C. | Santos, P.J.A., Philippines Univ. Los Banos, College, Laguna (Philippines). Inst. of Plant Breeding-Crop Science Cluster | Reano, C.E., Philippines Univ. Los Banos, College, Laguna (Philippines). Inst. of Statistics
The damage to corn crop production due to drought caused by the El Nino episodes that hit the Philippines from 1990 to 1992 was estimated to be as much as PhP 3.2 B. Large losses can be avoided b y developing corn varieties with the ability to produce relatively good yields under water-limited conditions. To produce good yield, varieties must also be able to absorb and utilize nutrients especially nitrogen efficiently. Experiments were conducted using different levels of nitrogen fertilizer (0, 60 and 120 kg N/ha) and water stress (irrigated and non-irrigated). Corn seedlings were grown for 3 to 4 weeks in trays using sand culture in the greenhouse. Field experiments were conducted in Laguna and Ilocos Norte using selected corn genotypes to measure the grain yield and validate results of greenhouse experiments. Genotypes with seedlings that have higher shoot length, shoot weight, root length, root weight, total N-uptake and total dry matter yield after drought treatment were also found to give better grain yields and to have higher nitrogen use efficiency potential when grown under intermediate water stress in the field. These genotypes were identified to be CML8, IPB Var 4, P6-1-3, (P6-1-3 x CML 337), (PK2/Var 1-12-2-1-2 x CML 337), (CML 8 x CBR/PDC 2-5-2-4-5) for white corn and Var 7, 95-6, Pi17, (CL00331 x Pi 23) for yellow corn. A protocol for rapid greenhouse screening at seedling stage is presented while the performance of drought tolerant F1 hybrids will be validated on-farm before recommendation for variety release.
显示更多 [+] 显示较少 [-]