Insights into the gene and protein structures of the CaSWEET family members in chickpea (Cicer arietinum), and their gene expression patterns in different organs under various stress and abscisic acid treatments

Genome-wide identification, characterization, and expression analysis of the small auxin-up RNA gene family during zygotic and somatic embryo maturation of the cacao tree (Theobroma cacao)

Small auxin-up RNA (SAUR) proteins were known as a large family that supposedly participated in various biological processes in higher plant species. However, the SAUR family has been still not explored in cacao (Theobroma cacao L.), one of the most important industrial trees. The present work, as an in silico study, revealed comprehensive aspects of the structure, phylogeny, and expression of TcSAUR gene family in cacao. A total of 90 members of the TcSAUR gene family have been identified and annotated in the cacao genome. According to the physic-chemical features analysis, all TcSAUR proteins exhibited slightly similar characteristics. Phylogenetic analysis showed that these TcSAUR proteins could be categorized into seven distinct groups, with 10 sub-groups. Our results suggested that tandemly duplication events, segmental duplication events, and whole genome duplication events might be important in the growth of the TcSAUR gene family in cacao. By re-analyzing the available transcriptome databases, we found that a number of TcSAUR genes were exclusively expressed during the zygotic embryogenesis and somatic embryogenesis. Taken together, our study will be valuable to further functional characterizations of candidate TcSAUR genes for the genetic engineering of cacao.

Plant phosphate status influences root biotic interactions

Phosphorus (P) deficiency stress in combination with biotic stress(es) severely impacts crop yield. Plant responses to P deficiency overlapping with that of other stresses exhibit a high degree of complexity involving different signaling pathways. On the one hand, plants engage with rhizosphere microbiome/arbuscular mycorrhizal fungi for improved phosphate (Pi) acquisition and plant stress response upon Pi deficiency; on the other hand, this association is gets disturbed under Pi sufficiency. This nutrient-dependent response is highly regulated by the phosphate starvation response (PSR) mediated by the master regulator, PHR1, and its homolog, PHL. It is interesting to note that Pi status (deficiency/sufficiency) has a varying response (positive/negative) to different biotic encounters (beneficial microbes/opportunistic pathogens/insect herbivory) through a coupled PSR-PHR1 immune system. This also involves crosstalk among multiple players including transcription factors, defense hormones, miRNAs, and Pi transporters, among others influencing the plant-biotic-phosphate interactions. We provide a comprehensive view of these key players involved in maintaining a delicate balance between Pi homeostasis and plant immunity. Finally, we propose strategies to utilize this information to improve crop resilience to Pi deficiency in combination with biotic stresses.

Molecular Breeding and Drought Tolerance in Chickpea

Cicer arietinum L. is the third greatest widely planted imperative pulse crop worldwide, and it belongs to the Leguminosae family. Drought is the utmost common abiotic factor on plants, distressing their water status and limiting their growth and development. Chickpea genotypes have the natural ability to fight drought stress using certain strategies viz., escape, avoidance and tolerance. Assorted breeding methods, including hybridization, mutation, and marker-aided breeding, genome sequencing along with omics approaches, could be used to improve the chickpea germplasm lines(s) against drought stress. Root features, for instance depth and root biomass, have been recognized as the greatest beneficial morphological factors for managing terminal drought tolerance in the chickpea. Marker-aided selection, for example, is a genomics-assisted breeding (GAB) strategy that can considerably increase crop breeding accuracy and competence. These breeding technologies, notably marker-assisted breeding, omics, and plant physiology knowledge, underlined the importance of chickpea breeding and can be used in future crop improvement programmes to generate drought-tolerant cultivars(s).