Cowpea leaf width correlates with above ground biomass across diverse environments

Abstract

Cowpea (Vigna unguiculata [L.] Walp.) yields within the dry savannahs of Sub-Saharan Africa are low. Given the contribution of cowpea to food security in this region, it is essential that high-yielding varieties are developed to improve crop productivity in a sustainable manner. Identifying morphological or physiological traits that correlate with biomass could assist breeders with rapid screening of diverse germplasm. This study investigated 23 diverse Nigerian cowpea lines in an environmentally controlled greenhouse and 50 diverse lines from a Multiparent Advanced Generation Intercross (MAGIC) population in the field to identify easily measurable traits associated with high above ground biomass. Correlation analyses found that leaf traits were significantly and positively correlated with above ground biomass, and the leaf width of the youngest fully expanded leaf was the best indicator of biomass yield. Analysis of variance identified significant differences among the genotypes for all measured traits, indicating that there is genetic variation among these varieties and opportunity for selection. These results from the greenhouse and the field indicate that the leaf width of the youngest fully expanded leaf can be used to rapidly select cowpea lines with high biomass production potential.

Dissecting the genetic architecture of leaf morphology traits in mungbean (Vigna radiata (L.) Wizcek) using genome‐wide association study

“…Image analysis was used to extract traits from the images. The traits extracted (Table 1) were guided by what is provided in the manual of leaf architecture (Ash et al., 1999) and other articles reviewed (Digrado et al., 2022; Y. Wang, Jin, et al., 2019; X. Yu et al., 2020) and as diagrammed in Figure 1. The trait extraction pipeline is easily scalable with small modifications to real‐time settings where the images could be captured nondestructively in their natural setting.…”

“…Simple models included using a single variable such as length, width, and perimeter traits, while multiple models included a combination of length and width. The parameters length, width, and perimeter are simple to measure on a small scale hence have frequently been used in the estimation of leaf area in other crops such as soybean (Bakhshandeh et al., 2011; Wiersma & Bailey, 1975), cowpea (Digrado et al., 2022), mungbean (Hamid & Agata, 1989), vines (X. Yu et al., 2020), and other crops (cereal and legumes) as tabulated by Bakhshandeh et al. (2010).…”

“…Image analysis was used to extract traits from the images. The traits extracted (Table 1) were guided by what is provided in the manual of leaf architecture (Ash et al, 1999) and other articles reviewed (Digrado et al, 2022;Y. Wang, Jin, et al, 2019;X.…”

“…Yu et al, 2020). Previous studies have found a positive correlation between a single leaf photosynthetic rate, biomass, and yield in Cassava (Manihot esculenta Crantz) (El-Sharkawy et al, 1990), cowpea (Vigna unguiculata (L.) Walp) (Digrado et al, 2022), and soybean (Glycine max) (Boerma & Ashley, 1988). For example, soybean narrow leaflet type cultivars have more seeds per pod than their broad leaflet counterpart, which can lead to a potential yield increase (Dinkins et al, 2002;Jeong et al, 2011;Sayama et al, 2017).…”

Multiple Leaf Sample Extraction System (MuLES): A tool to improve automated morphometric leaf studies

“…In addition, variability in functional leaf traits, such as leaf size and shape, has been shown to be linked to differential plant responses to environmental pressures (Pérez‐Harguindeguy et al, 2013; Schrader et al, 2021). Leaves are the main photosynthetic organs in plants, and differences in these functional leaf traits are known to have an impact on plant productivity, including effects on total yield (Fan et al, 2015; Cui et al, 2017), seed size (Huang et al, 2018), and aboveground biomass (Digrado et al, 2022), highlighting the importance of morphometric analyses for these particular plant organs.…”