Agronomic and physiological responses of Chinese facultative wheat genotypes to high-yielding Mediterranean conditions

Abstract

SUMMARYNine wheat genotypes, bred for the high-input agronomical conditions of Henan Province (China), were tested under the high-yielding Mediterranean conditions of Spain. Two cultivars widely grown in the zone were included as controls. Crop growth and leaf chlorophyll (Chl) content, leaf stomatal conductance (gs) and canopy temperature (CT) were measured during the crop cycle and stable carbon (C), oxygen (O) and nitrogen (N) isotope compositions (δ13C, δ18O and δ15N) were analysed on different plant parts. The lower yield of the Chinese genotypes compared with the controls was due to fewer grains/unit area, associated with lower tillering and a plant height clearly below the optimal range. Moreover, Chinese wheat exhibited a lower spike fertility index than the controls, and this was associated with a less compact spike structure. The physiological characteristics that were related to better performance under high-yielding Mediterranean conditions consisted of a higher green aerial biomass, particularly during the reproductive stage, together with more favourable water conditions (higher gs and lower CT and δ13C), the capacity to take up water during grain fill (higher δ18O) and a more efficient uptake (lower δ15N) and utilization (lower leaf N and Chl content) of N fertilizer. It is concluded that Chinese genotypes exhibited a low acclimation capacity to the moderate stress typical of the high-yielding Mediterranean conditions.

Relative Contribution of Nitrogen Absorption, Remobilization, and Partitioning to the Ear During Grain Filling in Chinese Winter Wheat

“…In the current study, a high grain yield was obtained compared to the results reported in other trials performed in China (Zheng et al, 2011 ; Xiao et al, 2012 ) and Spain (Zhou et al, 2015 ). The genotypes with higher grain yield exhibited taller shoots and larger grain numbers.…”

“…Four Chinese bread wheat ( Triticum aestivum L.) cultivars were evaluated; Yumai 2, Lankao 198, Yumai 20, and Zhoumai 18, which have been released and mainly distributed in the Henan Province of China. The cultivars used in this experiment were selected based on their similar phonologies and different yield performances, which have been described in a previous field experiment (Zhou et al, 2014 , 2015 ). The genotypes were planted in 30 L polyvinyl chloride pots filled with sand.…”

Genetic Advance of Durum Wheat Under High Yielding Conditions: The Case of Chile

“…Plant height was negatively correlated with the year of release in Australia, in cultivars developed between 1958 and 1973, but not in cultivars released after 1973 [30], and in China, in cultivars released between 1960 and 2000 [34]. A negative correlation between plant height and GY was also reported in the study of Zhou et al [34]. However, the comparison of advanced lines produced during the last decade ( Figure 2) showed a positive correlation between plant height and GY.…”

“…Plant height was reduced from 107 cm in 1964 to an average of 90 cm for the period 1970-2010 ( Figure 1A), and this was the consequence of the introduction of semi-dwarfing genes in Chile in the late 1950s [33]. Plant height was negatively correlated with the year of release in Australia, in cultivars developed between 1958 and 1973, but not in cultivars released after 1973 [30], and in China, in cultivars released between 1960 and 2000 [34]. A negative correlation between plant height and GY was also reported in the study of Zhou et al [34].…”

Wheat ear carbon assimilation and nitrogen remobilization contribute significantly to grain yield

“…Although Zhou et al () showed a positive relationship between grain yield and the number of kernels per ear and ear length, in our study these relationships were not found (Table S1). The fact that yield data also revealed that high grain‐yielding genotypes exhibited more ears and kernels (Table ), together with the fact that grain yield was not associated with bigger ears or kernels, suggests that the number of ears per plant had a greater impact on grain yield than the number and size of kernels per ear (Valério et al ; Zhou et al ). As was recorded previously (Valério et al ; Zhou et al ), this contribution of the number of ears per plant to the grain yield could indicate that tillering capacity was the main factor determining grain yield and biomass.…”