Chromosomal Location of Traits Associated with Wheat Seedling Water and Phosphorus Use Efficiency under Different Water and Phosphorus Stresses

Cheng-Xu Sun,Hong-Xing Cao,Hong-Bo Shao,Zheng-Bin Zhang,Ping Xu,Wei-Yi Song

doi:10.3390/ijms10094116

Abstract

The objective of this study was to locate chromosomes for improving water and phosphorus-deficiency tolerance of wheat at the seedling stage. A set of Chinese Spring-Egyptian Red wheat substitution lines and their parent Chinese Spring (recipient) and Egyptian Red (donor) cultivars were measured to determine the chromosomal locations of genes controlling water use efficiency (WUE) and phosphorus use efficiency (PUE) under different water and phosphorus conditions. The results underlined that chromosomes 1A, 7A, 7B, and 3A showed higher leaf water use efficiency (WUEl = Pn/Tr; Pn = photosynthetic rate; Tr = transpiration rate) under W-P (Hoagland solution with 1/2P), -W-P (Hoagland solution with 1/2P and 10% PEG). Chromosomes 7A, 3D, 2B, 3B, and 4B may carry genes for positive effects on individual plant water use efficiency (WUEp = biomass/TWC; TWC = total water consumption) under WP (Hoagland solution), W-P and -W-P treatment. Chromosomes 7A and 7D carry genes for PUE enhancement under WP, -WP (Hoagland solution with 10% PEG) and W-P treatment. Chromosome 7A possibly has genes for controlling WUE and PUE simultaneously, which indicates that WUE and PUE may share the same genetic background. Phenotypic and genetic analysis of the investigated traits showed that photosynthetic rate (Pn) and transpiration rate (Tr), Tr and WUEl showed significant positive and negative correlations under WP, W-P, -WP and -W-P, W-P, -WP treatments, respectively. Dry mass (DM), WUEP, PUT (phosphorus uptake) all showed significant positive correlation under WP, W-P and -WP treatment. PUE and phosphorus uptake (PUT = P uptake per plant) showed significant negative correlation under the four treatments. The results might provide useful information for improving WUE and PUE in wheat genetics.

Highlights

Drought stress is the most important and common environmental issues which limits agricultural production and decreases the efficiency of dry lands [1,2,3]
The two parents were originally chosen because of their large differences in drought tolerance (Egyptian Red and Chinese Spring are drought tolerant and drought sensitive varieties, respectively), large differences between the two parents were observed for the investigated traits
Chinese Spring had higher phosphorus use efficiency (PUE) than that of Egyptian Red under WP, -WP and W-P treatment (Table 5).This might be a reflection of the fact that Egyptian Red is more tolerant to water and phosphorous deficiency than

Summary

Introduction

Drought stress is the most important and common environmental issues which limits agricultural production and decreases the efficiency of dry lands [1,2,3]. Phosphorus is often considered the most limiting nutrient for plant growth in soils, especially in dry land [4,5]. The main reason may be the lower phosphorus use efficiency (PUE) of crops, total phosphorus (P) in the soil may be high, it is often present in unavailable forms or in forms that are only available outside of rhizosphere [6,7], large amounts of P fertilizer and poorly managed irrigation systems may lead to P accumulation and pollution of surface and ground waters. To obtain available P from soil, one method is by adding P fertilizer in soil, the second method is by planting high PUE crop varieties [8,9]

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Conclusion