An application of digital imagery analysis to understand the effect of N application on light interception, radiation use efficiency, and grain yield of maize under various agro-environments in Northern Mozambique

<p>Light-based analysis is a fundamental approach to quantify the effects of factors determining crop growth in a given environment. The objectives of this study are to confirm the applicability of a digital imagery technique to extract green leaf areas for estimating light interception (LI) of maize canopy and to understand the effect of fertilizer application on the LI and radiation use efficiency (RUE) of maize under various agro-environments in Northern Mozambique. A locally recommended variety, Matuba, was grown in a single season with three different N application rates (0, 30, and 80 kgN ha⁻¹) at one hot/dry low-elevation site, two hot/humid mid-elevation sites, and one cool/humid high-elevation site. Repeated measurements with quantum sensors revealed that the digital imagery is applicable to estimate the LI of maize except for leaf-senescing period close to maturity. The N application demonstrated profitable yield increases with agronomic nitrogen use efficiencies (kg grain yield per kg N input) of 20.6–35.3 kg kg⁻¹ except for the low-elevation site with severe drought stress. In the mid-elevation sites, the yield increases were mostly explained by the improvement of RUE while the effect on LI was small because the vegetative growth was naturally vigorous under high temperatures irrespective of N inputs. At the high-elevation site, the N application improved its stagnant initial canopy development and increased both RUE and LI. The simple and inexpensive imagery technique should be useful to identify physiological basis of maize responses to fertilizer application and its interaction with regional environment even under poorly equipped regions in the tropics.</p

Correction: Genetic Dissection of Drought and Heat Tolerance in Chickpea through Genome-Wide and Candidate Gene-Based Association Mapping Approaches

<p>Correction: Genetic Dissection of Drought and Heat Tolerance in Chickpea through Genome-Wide and Candidate Gene-Based Association Mapping Approaches</p

Geographic origin and population structure of chickpea reference set.

<p>a) the distribution of chickpea reference set, <i>desi</i> in red, <i>kabuli</i> in green, pea-shaped in orange and wild in yellow color dots b) ΔK is function of k from the structure run, the plateau at k = 3 indicates number of sub-populations in the reference set; c) Clustering of chickpea set genotypes into three groups (Group I, Group II and Group III).</p

Linage disequilibrium (LD) decay across all linkage groups.

<p>The overall LD decay across the genome is at 5</p

Significant marker trait associations (MTAs) for δ¹³C and 100 seed weight mapped on to “<i>QTL-hotspot</i>” on CaLG04 of intra-specific map of chickpea.

<p>(a) Genome wide association scan for δ13C; the Y-axis represent -log₁₀(P) values of the P-value of the MTAs, while linkage groups are indicated on X-axis. (b) Genome wide association scan for 100SDW. (c) “<i>QTL-hotspot</i>” on CaLG04 of chickpea intra-specific genetic map harboring QTLs for drought tolerance related traits. Significant MTAs for 100SDW and δ13C falling in the QTL region are indicated using the arrows in red, the traits are indicated using dotted rectangles in green.</p

Candidate gene- based marker trait associations

<p>Candidate gene- based marker trait associations</p

Significant marker-trait associations (MTAs) identified for different traits

<p>Significant marker-trait associations (MTAs) identified for different traits</p

Significant marker trait associations with >25% phenotypic variations and their effects on the trait

<p>*GB-SNP =  Gene based SNP.</p