Internal nutrient efficiencies, fertilizer recovery rates and indigenous nutrient supply of irrigated lowland rice in Sahelian West Africa

Yam (Dioscorea spp.) is a major food security crop for millions of resource-poor farmers, particularly in West Africa. Soil mineral deficiency is the main challenge in yam production, especially with the dwindling of fallow lands for the indigenous nutrient supply. Cultivars tolerant to available low soil nutrients and responsive to added nutrient supply are viable components of an integrated soil fertility management strategy for sustainable and productive yam farming systems in West Africa. This study’s objective was to identify white Guinea yam (D. rotundata) genotypes adapted to available low soil nutrients and responsive to externally added nutrient supply. Twenty advanced breeding lines and a local variety (Amula) were evaluated under contrasting soil fertility, low to expose the crop to available low soil nutrient supply and high to assess the crop response to added mineral fertilizer (NPK) input at Ibadan, Nigeria. The genotypes expressed differential yield response to low soil fertility (LF) stress and added fertilizer input. Soil fertility susceptibility index (SFSI) ranged from 0.64 to 1.34 for tuber yield and 0.60 to 1.30 for shoot dry weight. The genotypes R034, R041, R050, R052, R060, R100, and R125 combined lower SFSI with a low rate of reduction in tuber yield were identified as tolerant to LF stress related to the soil mineral deficiency. Likewise, the genotypes R109, R119, and R131 showed high susceptibility to soil fertility level and/or fertilizer response. Genotypes R025 and R034 had the tuber yielding potential twice of that the local variety under low soil nutrient conditions. Shoot dry weight and tuber yield showed a positive correlation both under low and high soil fertility conditions (r = 0.69 and 0.75, respectively), indicating the vigor biomass may be a morphological marker for selecting genotypes of white Guinea yam for higher tuber yield. Our results highlight genotypic variation in the tolerance to low soil nutrients and mineral fertilizer response in white Guinea yam to exploit through breeding and genetic studies to develop improved genotypes for low and high input production systems in West Africa.

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Oxalate and EDTA extractable soil phosphorus and iron in relation to P availability in lowland rice soils of West Africa

Ghana Journal of Agricultural Science ◽

10.4314/gjas.v32i2.1901 ◽

1999 ◽

Vol 32 (2) ◽

Author(s):

LT Narteh ◽

KL Sahrawat

Keyword(s):

West Africa ◽

Soil Phosphorus ◽

Lowland Rice ◽

P Availability ◽

Rice Soils ◽

Extractable Soil

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Assessment of Indigenous N, P and K Supply for Rice Site Specific Nutrient Management in Buru Regency

Journal of Tropical Soils ◽

10.5400/jts.2014.v19i3.151-159 ◽

2015 ◽

Vol 19 (3) ◽

pp. 151

Author(s):

Andriko Noto Susanto ◽

Marthen Pasang Sirappa

Keyword(s):

Nutrient Management ◽

Nutrient Supply ◽

Growth And Yield ◽

Limiting Factors ◽

Rice Soil ◽

Site Specific ◽

Average Value ◽

Fertilizer Recommendation ◽

Optimal Target ◽

Indigenous Nutrient Supply

Rate of fertilizer that should be applied to rice soil based on Site Specific Nutrient Management (SSNM) depends on indigenous nutrient supply, its recovery efficiency, and the amount of nutrients requirement to achieve the yield target. Research on nutrient omission plot was conducted in farmers irrigated land on Waeapo plain, Buru Island. In this area, N, P, and K were the main limiting factors of rice growth and yield. To overcome the constraint, this assessment was conducted to determine the indigenous supply of N, P and K and optimal target of rice productivity. Results of this assessment showed that the average of rice optimum productivity (Mg grain water content/w.c. 14% ha-1) in Waeapo plain was 6.55 Mg DGM (Dry Grain Milled) ha-1, with range from 5.6 to 7.3 Mg DGM ha-1 depended on the indigenous supply of N, P and K. The average value of the indigenous N, P and K supplies in Waeapo plain Buru was 65.59 kg N ha-1, 13.70 kg P ha-1 and 78.65 kg K ha-1, respectively while average productivity of rice on that indigenous N, P and K supplies was 5.05, 5.96 and 6.05Mg DGM ha-1, respectively. The value of indigenous nutrient supply of this nutrient can be used as a basis of fertilizer recommendation with the SSNM concept. Keywords: Indigenous nutrient supply; nitrogen; phosphorus; potassium; Site Specific Nutrient Management [How to Cite: Andriko NS and MP Sirappa. 2014. Assessment of Indigenous N, P and K Supply for Rice Site Specific Nutrient Management in Buru Regency. J Trop Soils 19: 151-159. Doi: 10.5400/jts.2014.19.3.151]

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