TY - JOUR
T1 - Differential nitrogen supply causes large variability in photosynthetic traits in wheat germplasm
AU - Veres, Szilvia
AU - Malik, Al Imran
AU - Rengel, Zed
PY - 2017/9/21
Y1 - 2017/9/21
N2 - Increased food production and enhanced sustainability depend on improving nitrogen-use efficiency (NUE) of crops. Breeding for enhanced NUE can take advantage of doubled-haploid populations derived from parents differing in the trait. This study evaluated variation in photosynthetic parameters at various growth stages in 43 wheat genotypes (parents of the existing doubled-haploid mapping populations) under optimal and low (one-quarter of the optimal) N supply. For relative chlorophyll content, the genotype×N treatment interaction was significant at tillering, booting, pre-anthesis and anthesis. Genotypes with small differences in relative chlorophyll content between the two N supplies were CD87 at tillering and pre-anthesis, and Batavia at anthesis. Potential photochemical activity (Fv/Fm) was measured at tillering and anthesis. The genotype×N treatment interaction was significant in both growth stages. Based on net photosynthesis, stomatal conductance and intrinsic water usez efficiency, there was variable potential of the genotypes to cope with low N supply; significant differences were found among genotypes at ambient CO2 and between N treatments at elevated CO2 concentration (2000molmol-1) for all three parameters. Based on all studied parameters, a dissimilarity matrix was constructed, separating the 43 genotypes into four groups. Group 2 comprised 15 of the genotypes (Batavia, Beaver, Calingiri, CD87, Frame, Krichauff, Neepawa, Soissons, Spear, Stiletto, WAWHT2036, WAWHT2074, Westonia, Wilgoyne, Yitpi), characterised by small differences in relative chlorophyll content and Fv/Fm caused by different N supply at tillering and anthesis. These genotypes therefore appear to have relative tolerance to low N supply and a potential to be used in discerning the molecular basis of tolerance to low N supply.
AB - Increased food production and enhanced sustainability depend on improving nitrogen-use efficiency (NUE) of crops. Breeding for enhanced NUE can take advantage of doubled-haploid populations derived from parents differing in the trait. This study evaluated variation in photosynthetic parameters at various growth stages in 43 wheat genotypes (parents of the existing doubled-haploid mapping populations) under optimal and low (one-quarter of the optimal) N supply. For relative chlorophyll content, the genotype×N treatment interaction was significant at tillering, booting, pre-anthesis and anthesis. Genotypes with small differences in relative chlorophyll content between the two N supplies were CD87 at tillering and pre-anthesis, and Batavia at anthesis. Potential photochemical activity (Fv/Fm) was measured at tillering and anthesis. The genotype×N treatment interaction was significant in both growth stages. Based on net photosynthesis, stomatal conductance and intrinsic water usez efficiency, there was variable potential of the genotypes to cope with low N supply; significant differences were found among genotypes at ambient CO2 and between N treatments at elevated CO2 concentration (2000molmol-1) for all three parameters. Based on all studied parameters, a dissimilarity matrix was constructed, separating the 43 genotypes into four groups. Group 2 comprised 15 of the genotypes (Batavia, Beaver, Calingiri, CD87, Frame, Krichauff, Neepawa, Soissons, Spear, Stiletto, WAWHT2036, WAWHT2074, Westonia, Wilgoyne, Yitpi), characterised by small differences in relative chlorophyll content and Fv/Fm caused by different N supply at tillering and anthesis. These genotypes therefore appear to have relative tolerance to low N supply and a potential to be used in discerning the molecular basis of tolerance to low N supply.
KW - chlorophyll fluorescence
KW - intrinsic water-use efficiency
KW - relative chlorophyll content
KW - stomatal conductance
UR - http://www.scopus.com/inward/record.url?scp=85031493150&partnerID=8YFLogxK
U2 - 10.1071/CP17126
DO - 10.1071/CP17126
M3 - Article
AN - SCOPUS:85031493150
SN - 1836-0947
VL - 68
SP - 703
EP - 712
JO - Crop and Pasture Science
JF - Crop and Pasture Science
IS - 8
ER -