2.3.1. Experiment A
The experiment was seeded on 8 December 1996. Dry seed was direct sown by hand at a rate of 3–6 seeds per hill at a depth of 2–3 cm in rows 0.15 m apart and hills within each row were spaced 0.17 m apart. After seeding, uniform sprinkler irrigation was applied until the plants reached the two to three leaf stage. At this stage, seedlings were thinned to 1 seedling per hill so as to keep a uniform plant number per hill. Irrigation was applied daily to the depth of between 1 and 5 cm after thinning for 2 days then a mixed commercial chemical fertiliser was applied at the rate of 19–38–38 kg N–P2O5–K2O ha−1 after irrigation. Insecticide Furadan (Cabofuran 3% granular) was applied, at the same time as the fertiliser application, at the rate of 31 kg ha−1 to prevent nematodes attacking the roots.
In order to simulate wet season drought conditions, soil water in the experimental field was managed to be either flooded or with no standing water. The experimental soil was flooded, dried out for a few days and sprinkler irrigated to wet the soil, and this was alternated for four cycles, until 50 days after seeding (DAS) when watering was withheld to induce drought stress.