Exploring genetic variation for salinity tolerance in chickpea using image-based phenotyping

Abstract

Soil salinity results in reduced productivity in chickpea. However, breeding for salinity tolerance is challenging because of limited knowledge of the key traits affecting performance under elevated salt and the difficulty of high-throughput phenotyping for large, diverse germplasm collections. This study utilised image-based phenotyping to study genetic variation in chickpea for salinity tolerance in 245 diverse accessions. On average salinity reduced plant growth rate (obtained from tracking leaf expansion through time) by 20%, plant height by 15% and shoot biomass by 28%. Additionally, salinity induced pod abortion and inhibited pod filling, which consequently reduced seed number and seed yield by 16% and 32%, respectively. Importantly, moderate to strong correlation was observed for different traits measured between glasshouse and two field sites indicating that the glasshouse assays are relevant to field performance. Using image-based phenotyping, we measured plant growth rate under salinity and subsequently elucidated the role of shoot ion independent stress (resulting from hydraulic resistance and osmotic stress) in chickpea. Broad genetic variation for salinity tolerance was observed in the diversity panel with seed number being the major determinant for salinity tolerance measured as yield. This study proposes seed number as a selection trait in breeding salt tolerant chickpea cultivars.

The carboxylate‐releasing phosphorus‐mobilizing strategy can be proxied by foliar manganese concentration in a large set of chickpea germplasm under low phosphorus supply

“…() and Atieno et al . (). Of the 100 genotypes, there were 79 desi types, 15 kabuli types and six pea‐shaped types.…”

Leaf transpiration plays a role in phosphorus acquisition among a large set of chickpea genotypes

“…Seeds of the collection were originally provided by ICRISAT and then multiplied at Shenton Park Field Station, The University of Western Australia. The information on all genotypes, including the country of origin, biological status (advanced cultivar, breeding material, and landrace) and seed type (desi, kabuli, or pea shaped) were described in Chen, Ghanem, and Siddique () and Atieno et al (). Of the 266 genotypes, 203 are desi types, 53 are kabuli types, and 10 are pea‐shaped types.…”

“…Crop genetic resources and the diversity present in the chickpea reference set provide a pathway to exploit the genetic diversity of chickpea, assurance for future genetic progress, and insurance against unforeseen threats to agricultural production (Atieno et al, ; Upadhyaya et al, ). Recently, this reference set has been studied for salinity tolerance in the glasshouse, which showed large variation in seed yield and yield components (Atieno et al, ). However, there has been no attempt to use this chickpea reference set to improve PUE.…”

Salt stress tolerance mechanisms and potential applications of legumes for sustainable reclamation of salt‐degraded soils

“…For example, Vadez et al () utilized a high‐throughput, three‐dimensional scanning method to observe leaf development in relation to plant water use in peanut ( Arachis hypogaea ) and cowpea ( Vigna unguiculata ) plants to gain a better understanding of the physiological processes associated with salinity stress. Atieno et al () used a high‐throughput, nondestructive, phenotyping platform to investigate 245 diverse accessions of chickpea to identify important agronomic traits for chickpea salt tolerance. Broad genetic variation for plant height, growth rate, leaf senescence, flowering period, shoot biomass, pod and seed numbers, and shoot Na + and K + levels under saline conditions and salinity tolerance traits were identified.…”

“…Several other major crops also show reduced performance on saline soils including rice (Oryza sativa), which is sensitive from vegetative to reproductive stages (Ghosh, Ali, & Saikat, 2016;Hariadi, Nurhayati, Soeparjono, & Arif, 2015), and wheat (Triticum aestivum; Alom, Hasan, Islam, & Wang, 2016;Sharma, 2015). Salinity also has an adverse effect on shoot biomass, pod set, and pod filling in chickpea (Cicer arietinum), causing reduced yields (Atieno et al, 2017;Flowers et al, 2010). Many vegetable crops are also susceptible to salinity stress, with the threshold (EC t ) of the majority of these crops being between 1 and 2.5 dS m −1 in saturated soil extracts, but variability exists among different crops, such as sweet pepper (Capsicum annuum), tomato (Solanum lycopersicum), and cucumber (Cucumis sativus; Machado & Serralheiro, 2017).…”