RATOONED LOWLAND NERICA RICE VARIETIES AS AN OPTION FOR TRIPLE CROPPING IN INLAND VALLEYS OF DERIVED SAVANNAH IN NIGERIA

SUMMARY Although triple cropping in inland valleys of Nigeria is technically feasible, the third crop between the main crop and dry season non-rice crop has been considered not to be economically viable because of poor crop establishment due to soil inundation. The identification of an appropriate technology with low input, such as ratooning, would allow this niche to be utilized. Field experiments were conducted at the University of Agriculture, Abeokuta, Nigeria in 2007–2008 and 2008–2009 cropping seasons to evaluate the performance of the main and ratooned crops of lowland NERICA (New Rice for Africa) rice (Oryza sativa L.) varieties in a lowland rice–ratooned rice–fluted pumpkin (Telfairia occidentalis Hook F.) sequence. The experiment was laid out in a randomized complete block design with three replicates. The lowland rice varieties used were NERICA-L 19, NERICA-L 20, NERICA-L 22, NERICA-L 24, OFADA, NERICA-L 26, NERICA-L 41, NERICA-L 42, NERICA-L 44 and NERICA-L 47. The grain yield of the main rice crop ranged from 5.0 to 7.3 t ha−1 in 2007–2008 cropping season and from 4.1 to 9.1 t ha−1 in 2008–2009. The ratooned rice had a grain yield of 1.0–4.7 t ha−1 in 2007–2008 and 1.2–3.4 t ha−1 in 2008–2009. The total grain yield obtained in 2007–2008 from the main and ratooned rice crops in seven months was 6.7–11.6 t ha −1 , while in 2008–2009 it was 5.3–2.6 t ha −1 . The fresh leaf yield of fluted pumpkin ranged from 14.6 to 16.9 t ha −1 in 2007–2008 and from 18.3 to 19.8 t ha −1 in 2008–2009, similar to previously reported rainy season unfertilized yields. Thus, a ratooned rice crop appears to be a feasible technology capable of boosting rice production and consequently increasing the overall productivity of the inland valley in a rice–rice–vegetable cropping sequence.