Variation in carbon isotope discrimination and its relationship with harvest index in the reference collection of chickpea germplasm

Terminal drought is a major constraint to chickpea productivity. Carbon isotope discrimination (Δ13C), an integrator of plant behaviour influencing transpiration efficiency (TE), is an important component of yield under drought. The variation in Δ13C and its association with yield was assessed in the reference collection of chickpea germplasm. Drought stress reduced shoot biomass by 36–39% and grain yield by 23%. Mean Δ13C was low and the range of genetic variation was high under drought stress. Largely, high Δ13C accessions were early in flowering (40–50 days), moderate in shoot biomass, high in seed yields and high in harvest index (HI). Δ13C was positively correlated with seed yield in both the years under drought stress, only in 2008–09 under optimal irrigation. This positive association was very close with HI. Among the yield components, Δ13C was closely associated with pod numbers per unit area and seed size under drought stress. Path coefficients showed no direct association of Δ13C with grain yield but an indirect negative association through shoot biomass at maturity and a close positive association through HI. The closest association of HI or shoot biomass was seen in the maturity group of accessions that experienced the optimum terminal drought stress.

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Relationships between carbon isotope discrimination and leaf morphophysiological traits in spring-planted spring wheat under drought and salinity stress in Northern China

Australian Journal of Agricultural Research ◽

10.1071/ar07476 ◽

2008 ◽

Vol 59 (10) ◽

pp. 941 ◽

Cited By ~ 11

Author(s):

Lin Zhu ◽

Zong Suo Liang ◽

Xing Xu ◽

Shu Hua Li ◽

Ji Hai Jing ◽

...

Keyword(s):

Grain Yield ◽

Carbon Isotope ◽

Harvest Index ◽

Carbon Isotope Discrimination ◽

Water Status ◽

Flag Leaf ◽

Wheat Yield ◽

Gas Exchange Parameters ◽

Isotope Discrimination ◽

North East

The relationships between carbon isotope discrimination (Δ) and some morphophysiological traits such as specific leaf dry weight (SLDW), gas exchange parameters, and relative water content (RWC) were studied in a collection of 20 bread wheat cultivars (landraces, released cultivars and advanced lines) in three locations of the Ningxia region (North-East China), i.e. Yinchuan (limited irrigation conditions), Huinong (limited irrigation conditions + salinity) and Guyuan (rain-fed conditions). Relationships between Δ, grain yield (GY), and harvest index (HI) and above-ground biomass (AGB) were also analysed. Differences in the measured traits between different locations were highly related to the variation in water availability. Positive correlations were noted between Δ and HI and grain yield. Flag leaf Δ was positively correlated with RWC at anthesis, and negatively associated with SLDW at grain filling. Significant and negative correlations between Δ and dry matter weight per plant at anthesis and biomass at maturity were noted. Leaf temperature (LT) was found to be negatively correlated with Δ and gs. The findings suggest that Δ may be a useful indicator reflecting wheat yield, harvest index, and water status under irrigation and rain-fed conditions in the Ningxia region.

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Relationship of grain yield with carbon isotope discrimination and ash content in lines derived from a bread wheat cultivar

The Journal of Agricultural Science ◽

10.1017/s0021859605005356 ◽

2005 ◽

Vol 143 (4) ◽

pp. 275-282 ◽

Cited By ~ 7

Author(s):

J. T. TSIALTAS ◽

I. S. TOKATLIDIS ◽

E. TAMOUTSIDIS ◽

I. XYNIAS

Keyword(s):

Grain Yield ◽

Carbon Isotope ◽

Bread Wheat ◽

Carbon Isotope Discrimination ◽

Selection Criterion ◽

Ash Content ◽

Individual Plant ◽

Low Density ◽

Isotope Discrimination ◽

Relationship Of

The objective was to explore, in lines derived from a bread wheat (Triticum aestivum L.) cultivar, the association of grain yield with carbon isotope discrimination (Δ) and ash content (Ash) determined in both flag leaf and kernel. Divergent selection within the cv. Nestos, based on individual plant yield under very low density (11547 plants/ha), produced 20 lines. Progeny evaluation was conducted in two sites of Northern Hellas (Greece) at both low (11547 plants/ha) and high (5000000 plants/ha) density. The results showed significant differences between lines for grain yield, Δ and Ash. However, only the conclusions on grain yield were similar in low and high density, perhaps because the selection criterion under low density was grain yield. This, combined with the lack of any strong relationship of grain yield with either Δ or Ash, failed to confirm the usefulness of these physiological traits as indirect selection criteria, when the within-cultivar variation for grain yield is exploited. The possible association of grain yield with Δ and Ash appeared to be influenced by various factors such as drought, level of grain yield and altitude. Results also showed that less plant-to-plant variability, as expressed by the coefficients of variation (CV) of single-plant yields, was associated with decreased drought response and higher yield stability. The less stressed lines were those that used water more conservatively till anthesis and maintained a high photosynthetic rate during grain filling.

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Evidence for genotypic differences among elite lines of common bean in the ability to remobilize photosynthate to increase yield under drought

The Journal of Agricultural Science ◽

10.1017/s0021859616000915 ◽

2016 ◽

Vol 155 (6) ◽

pp. 857-875 ◽

Cited By ~ 21

Author(s):

I. M. RAO ◽

S. E. BEEBE ◽

J. POLANIA ◽

M. GRAJALES ◽

C. CAJIAO ◽

...

Keyword(s):

Drought Stress ◽

Grain Yield ◽

Common Bean ◽

Harvest Index ◽

Genotypic Differences ◽

Area Index ◽

Wild Bean ◽

Terminal Drought ◽

Terminal Drought Stress ◽

Pod Harvest Index

SUMMARYCommon bean (Phaseolus vulgaris L.) is the most important food legume for human consumption. Drought stress is the major abiotic stress limitation of bean yields in smallholder farming systems worldwide. The current work aimed to determine the role of enhanced photosynthate mobilization to improve adaptation to intermittent and terminal drought stress and to identify a few key adaptive traits that can be used for developing drought-resistant genotypes. Field studies were conducted over three seasons at Centro Internacional de Agricultura Tropical, Palmira, Colombia to determine genotypic differences in adaptation to intermittent (two seasons) and terminal (one season) drought stress compared with irrigated conditions. A set of 36 genotypes, including 33 common bean, two wild bean and one cowpea were evaluated using a 6 × 6 lattice design under irrigated and rainfed field conditions. Three common bean elite lines (NCB 226, SEN 56, SER 125) were identified with superior levels of adaptation to both intermittent and terminal drought stress conditions. The greater performance of these lines under drought stress was associated with their ability to remobilize photosynthate to increase grain yield based on higher values of harvest index, pod harvest index, leaf area index and canopy biomass. Two wild bean germplasm accessions (G 19902, G 24390) showed very poor adaptation to both types of drought stress. One small-seeded black line (NCB 226) was superior in combining greater values of canopy biomass with greater ability to mobilize photosynthates to grain under both types of drought stress. Two small-seeded red lines (SER 78, SER 125) seem to combine the desirable traits of enhanced mobilization of photosynthates to seed with effective use of water through canopy cooling under terminal drought stress. Pod harvest index showed significant positive association with grain yield under both types of drought stress and this trait can be used by breeders as an additional selection method to grain yield in evaluation of breeding populations for both types of drought stress.

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