Plant Characteristics of High‐Yielding Upland Rice Cultivars in West Africa

Abstract

In West Africa, upland rice (Oryza spp.) is typically grown in low‐input production systems under low soil fertility conditions. Genetic improvement may offer a cost‐effective approach to improving the productivity rather than approaches that rely solely on external nutrient inputs. In the 1990s, the upland rice breeding program of the West Africa Rice Development Association (now Africa Rice Center [AfricaRice]) developed New Rice for Africa (NERICA) cultivars. However, recent studies suggest that there is scope for improving on the currently available NERICA cultivars. The objectives of this study are to (i) quantify yield advantage of two cultivars (Aus 257 and IR 74371‐3‐1‐1) which were identified as high‐yielding ones from a wide range of materials, over NERICA 1, and (ii) identify plant characteristics of these two high‐yielding cultivars. Data were compiled from nine on‐station and 23 on‐farm trials in Benin. On average over all the trials, the two cultivars out yielded local check upland NERICA 1. Particularly, their relative yield advantage was higher when NERICA 1 showed low yield. Aus 257 had greater biomass accumulation, harvest index (HI), and uptake of N, P, and K. Greater biomass accumulation was the result of high leaf area index (LAI). Cultivar variation in nutrient‐use efficiency also contributed to high yield, and IR 74371‐3‐1‐1 showed higher nutrient‐use efficiency than NERICA 1 and Aus 257. These results suggest that the use of the two cultivars with greater biomass accumulation, harvest index, nutrient uptake, and use efficiency is critical for improving rice yield.

Progress in varietal improvement for increasing upland rice productivity in the tropics

“…poor soil fertility and heavy weed infestation. Since the publication of that paper, there have been many reports supporting this argument in West Africa (Saito, 2014(Saito, , 2016Saito & Futakuchi, 2014;Sito, Dieng, Vandamme, et al, 2015;Saito, Vandamme, Segda, et al, 2015;Vandamme et al, 2016a;Vandamme et al, 2016b). In East and Southern Africa, good performance of upland NERICA varieties has been frequently observed in field trials and on farm (Kijima et al, 2008;Sekiya et al, 2013;Shrestha et al, 2012).…”

“…Similar to results from Asia (Asai et al, 2009;Atlin et al, 2006;Saito et al, 2007), Saito and Futakuchi (2009), Saito et al (2012) identified B6144-F-MR-6-0-0 (an indica variety developed in Indonesia) as a potential donor for improving yield under low-input conditions. Aus257 was identified as early maturing and high yielding, with strong weed-suppressive ability and greater nutrient uptake than NERICA 1 (Saito, 2016;Saito & Futakuchi, 2014). IR 74371-3-1-1 (an indica variety developed in the Philippines) showed higher nutrient-use efficiency than NERICA 1, which contributed to higher yield in low-input conditions (Saito, 2016).…”

“…Aus257 was identified as early maturing and high yielding, with strong weed-suppressive ability and greater nutrient uptake than NERICA 1 (Saito, 2016;Saito & Futakuchi, 2014). IR 74371-3-1-1 (an indica variety developed in the Philippines) showed higher nutrient-use efficiency than NERICA 1, which contributed to higher yield in low-input conditions (Saito, 2016). Recently, DJ123 was also identified as a potential donor for tolerance to soil P deficiency and good responsiveness to P fertilizer application (Vandamme et al, 2016b(Vandamme et al, , 2018.…”

“…Aus genotypes could be useful genetic resource for Africa as well. Several protocols have recently been developed to improve screening (Saito, 2010(Saito, , 2014Sito, Dieng, Vandamme, et al, 2015, Saito, Vandamme, Segda, et al, 2015Vandamme et al, 2016b), and plant types required for high yield proposed (Saito, 2016;Saito & Futakuchi, 2009). …”

Factors Explaining Differences in Yield Response to High Nitrogen Fertilization among Rice Varieties under Tropical Highland Conditions in Central Kenya

“…3 and 4). Saito (2015) reported that grain yield per N uptake, that is, nitrogen-use efficiency (NUE), was lower in NERICA 1 than in other rice varieties (Aus 257 and IR 74371-3-1-1). Although N uptake was not determined in the present study, NUE may be lower in NERICA 1 than in BW196.…”