Generation mean analysis of phosphorus-use efficiency in freely nodulating soybean crosses grown in low-phosphorus soil

Veronica N E Uzokwe,Iyiola Fawole,Kenton Dashiell,Baffour Asafo-Adjei,Robert Abaidoo,Inakwu O A Odeh,David K Ojo,Nteranya Sanginga,R Singh

doi:10.1111/pbr.12453

Abstract

Freely nodulating soybean genotypes vary in their phosphorus (P) uptake and P-use efficiency (PUE) in low-P soils. Understanding the genetic basis of these genotypes’ performance is essential for effective breeding. To study the inheritance of PUE, we conducted crosses using two high-PUE genotypes, two moderate-PUE genotypes and two inefficient-PUE genotypes, and obtained F1, F2, BC1 and BC2 populations. The inheritance of PUE was evaluated using a randomized complete block design. A generation mean analysis of phenotypic data showed that PUE was heritable, with complex inheritance patterns and the presence of additive, dominance and epistatic gene effects. Seed P, shoot P, root P, P-incorporation efficiency and PUE were largely quantitatively inherited traits. There were dominance, additive × additive and dominance × dominance gene effects on PUE, grain yield, shoot dry weight, 100-seed weight, root dry weight and shoot dry matter per unit P for populations grown under low-P conditions. Dominance effects were generally greater than additive effects on PUE-related indices. These PUE indices can be used to select P-efficient soybean genotypes from segregating populations.

Highlights

Nodulating soybean genotypes are useful in the cerealand legume-based cropping systems of the African savanna (Sanginga et al 2002, Yusuf et al 2008)
There were dominance, additive 9 additive and dominance 9 dominance gene effects on P-use efficiency (PUE), grain yield, shoot dry weight, 100-seed weight, root dry weight and shoot dry matter per unit P for populations grown under low-P conditions
The objectives of this study were to determine the nature and magnitude of the genetic effects for PUE and related characters for a range of soybean crosses grown under low-P conditions

Summary

Introduction

Nodulating soybean genotypes are useful in the cerealand legume-based cropping systems of the African savanna (Sanginga et al 2002, Yusuf et al 2008). The objectives of this study were to determine the nature and magnitude of the genetic effects for PUE and related characters (grain yield, shoot dry weight, 100-seed weight, root dry weight and shoot dry matter per unit P in the shoot) for a range of soybean crosses grown under low-P conditions. This information will be useful for selecting P-efficient soybean varieties for cultivation in low-P soils

Objectives

Methods

Results

Conclusion