Screening forage and browse legumes germplasm to nutrient stresses: IV. Growth rates of Sesbania as affected by aluminum and low phosphorus in soils and nutrient solutions

Abstract

Esbania have multifarious utilization, and in many instances growth rate is one of the most important criteria for the selection of suitable esbania. This paper reports results of a study on the growth rates of esbania on two acid soils both low in available P, but one with toxic levels of Al. Growth rate was assessed by measuring plant height at 21, 29, 35, 45, 52, and 60 days on a Nitosol (Soddo soil), and at 52 and 60 days on a clay loam (Chencha soil). Growth was also evaluated in nutrient solutions containing 0, 3, and 6 ppm Al in combination with 155 and 6200 ppm P.

On the Soddo soil, the esbania varied in their growth rates, but responded similarly to liming the soil from pH 4.8 to 5.6 throughout the growing period. The accessions showed similar response to P during early growth, but varied sharply during late growth 35 to 60 days without P. Lime was progressively more effective with P applied. The growth patterns fell into four categories based on responses to P applied to the Soddo soil.

On the Chencha soil which had 77% Al saturation, the esbania differentially responded to liming the soil from pH 4.1 to 5.9 and to applied P at each growth interval. Accessions which had the best plant height on the Chencha soil were generally tolerant to Al.

Variability in the growth rates of accessions from different countries suggested potential for screening esbania for differential tolerance to soil acidity and low P in relation to source or origin.

Notes

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