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This study investigates spatiotemporal variability of residual soil moisture during the OND (October-November-December) season in Ethiopia and its implications for crop productivity. Employing advanced statistical techniques, we analyze spatial and temporal distribution of soil moisture across Ethiopia from 1981 to 2020, focusing on selected crops including legumes: chickpea, field peas, common bean, soybean and alfalfa, to assess the potential of residual moisture to support post-rainy season cropping. Results indicate pronounced east-west moisture gradients, with eastern regions of Ethiopia exhibiting lower moisture levels (< 60 kg.m-2) compared to western regions (> 150 kg.m-2). The central highlands, which are pivotal for agricultural activities, demonstrate significant variability in moisture (standard deviations > 25 kg.m-2), with implications on agricultural sustainability. The northern and southeastern tips of the country are particularly vulnerable to prolonged drought, where climate change and frequent dry spells exacerbate moisture deficits, consequently impacting crop productivity. Despite these challenges, promising opportunities for future crop production emerge in the southeastern region, which is characterized by increasing moisture trend over time (). Findings further indicate that residual moisture adequately meets and supports crop water requirements in the western, central, and southwestern Ethiopia. In these regions, residual moisture supports more than 90% of cropland water requirements of various crops during the initial and late-season growth stages, whereas water requirement coverage drops to less than 20% during the mid-season growth stage. Therefore, by utilizing residual soil moisture alongside supplemental irrigation, Ethiopian farmers can meet crop water needs for double cropping and enhance resilience to climate variability.

Plastid ribosomal proteins (PRPs) can play essential roles in plastid ribosome functioning that affect plant function and development. However, the roles of many PRPs remain unknown, including elucidation of which PRPs are essential or display redundancy. Here, we report that the nuclear-encoded PLASTID RIBOSOMAL PROTEIN L5 (PRPL5) is essential for early embryo development in A. thaliana, as homozygous loss-of-function mutations in the PRPL5gene impairs chloroplast development and leads to embryo failure to develop past the globular stage. We confirmed the prpl5embryo-lethal phenotype by generating a mutant CRISPR/Cas9 line and by genetic complementation. As PRPL5underwent transfer to the nuclear genome early in the evolution of Embryophyta,PRPL5 can be expected to have acquired a chloroplast transit peptide. We identify and validate the presence of an N-terminal chloroplast transit peptide, but unexpectedly also confirm the presence of a conserved and functional Nuclear Localization Signal on the protein C-terminal end. This study highlights the fundamental role of the plastid translation machinery during the early stages of embryo development in plants and raises the possibility of additional roles of plastid ribosomal proteins in the nucleus.

Seeds are valuable sources of carbohydrates, lipids, proteins, fibers, minerals, and vitamins. They provide energy and nutrition to germinating seedlings, food to humans, feed to livestock, and feedstocks to industry. High‐throughput analyses of gene expression in crops has identified many candidate genes associated with seed dormancy, longevity, germination, and vigor. In this review, we cover the latest research focusing on such key seed traits. Transcriptome analyses of time courses of seed filling have identified sets of genes expressed at different stages of this process. The potential role of epigenetics (including seed–endosperm imprinted genes) in regulating seed development and chemistry is highlighted herein. We also discuss how advances in genomics and seed biology are facilitating the unravelling of associations between seed traits with gene bank accessions and gene sequences, including how functional research can accelerate the discovery of allelic variants. Such knowledge of functional effects relating to gene variants is necessary for more efficient and cost‐effective management of genetic resources or for redesigning crops with specific seed characteristics. For instance, gene bank curators may assess seed viability by monitoring changes in gene expression of biomarker genes in dry seed samples to decide germplasm regeneration and assess genetic integrity of collections by monitoring changes in diversity and allele frequencies between samples of same accession stored in gene banks. We highlight that resistance to preharvest sprouting can be enhanced through genomics‐assisted breeding in otherwise nondormant rice (Oryza sativaL.) and wheat (Triticum aestivumL.) cultivars, while pimt, another valuable marker for seed longevity, may be deployed to enhance seed vigor in crops.

Reproduction in triploid plants is important for understanding polyploid population dynamics. We show that genetically identical reciprocal F1 hybrid triploids can display transgenerational epigenetic effects on viable F2 seed development. The success or failure of reproductive outcomes from intra-species crosses between plants of different ploidy levels is an important factor in flowering plant evolution and crop breeding. However, the effects of inter-ploidy cross directions on F1 hybrid offspring fitness are poorly understood. In Arabidopsis thaliana, hybridization between diploid and tetraploid plants can produce viable F1 triploid plants. When selfed, such F1 triploid plants act as aneuploid gamete production “machines” where the vast majority of gametes generated are aneuploid which, following sexual reproduction, can generate aneuploid swarms of F2 progeny (Henry et al. 2009). There is potential for some aneuploids to cause gametophyte abortion and/or F2 seed abortion (Henry et al. 2009). In this study, we analyse the reproductive success of 178 self-fertilized inter-accession F1 hybrid triploids and demonstrate that the proportions of aborted or normally developed F2 seeds from the selfed F1 triploids depend upon a combination of natural variation and cross direction, with strong interaction between these factors. Single-seed ploidy analysis indicates that the embryonic DNA content of phenotypically normal F2 seeds is highly variable and that these DNA content distributions are also affected by genotype and cross direction. Notably, genetically identical reciprocal F1 hybrid triploids display grandparent-of-origin effects on F2 seed set, and hence on the ability to tolerate aneuploidy in F2 seed. There are differences between reciprocal F1 hybrid triploids regarding the proportions of normal and aborted F2 seeds generated, and also for the DNA content averages and distributions of the F2 seeds. To identify genetic variation for tolerance of aneuploidy in F2 seeds, we carried out a GWAS which identified two SNPs, termed MOTand POT, which represent candidate loci for genetic control of the proportion of normal F2 seeds obtained from selfed F1 triploids. Parental and grandparental effects on F2 seeds obtained from selfed F1 triploids can have transgenerational consequences for asymmetric gene flow, emergence of novel genotypes in polyploid populations, and for control of F2 seed set in triploid crops.

Domestication of the now-extinct wild aurochs, Bos primigenius, gave rise to the two major domestic extant cattle taxa, B. taurusand B. indicus. While previous genetic studies have shed some light on the evolutionary relationships between European aurochs and modern cattle, important questions remain unanswered, including the phylogenetic status of aurochs, whether gene flow from aurochs into early domestic populations occurred, and which genomic regions were subject to selection processes during and after domestication. Here, we address these questions using whole-genome sequencing data generated from an approximately 6,750-year-old British aurochs bone and genome sequence data from 81 additional cattle plus genome-wide single nucleotide polymorphism data from a diverse panel of 1,225 modern animals. Phylogenomic analyses place the aurochs as a distinct outgroup to the domestic B. tauruslineage, supporting the predominant Near Eastern origin of European cattle. Conversely, traditional British and Irish breeds share more genetic variants with this aurochs specimen than other European populations, supporting localized gene flow from aurochs into the ancestors of modern British and Irish cattle, perhaps through purposeful restocking by early herders in Britain. Finally, the functions of genes showing evidence for positive selection in B. taurusare enriched for neurobiology, growth, metabolism and immunobiology, suggesting that these biological processes have been important in the domestication of cattle. This work provides important new information regarding the origins and functional evolution of modern cattle, revealing that the interface between early European domestic populations and wild aurochs was significantly more complex than previously thought.

Cancer epigenetics research is now entering an exciting phase of translational epigenetics whereby novel epigenome therapeutics is being developed for application in clinical settings. Epigenetics refers to all heritable and potentially reversible changes in gene or genome functioning that occurs without altering the nucleotide sequence of the DNA. A range of different epigenetic “marks” can activate or repress gene expression. While epigenetic alterations are associated with most cancers, epigenetic dysregulation can also have a causal role in cancer etiology. Epigenetically disrupted stem or progenitor cells could have an early role in neoplastic transformations, while perturbance of epigenetic regulatory mechanisms controlling gene expression in cancer-relevant pathways will also be a contribution factor. The reversibility of epigenetic marks provides the possibility that the activity of key cancer genes and pathways can be regulated as a therapeutic approach. The growing availability of a range of chemical agents which can affect epigenome functioning has led to a range of epigenetic-therapeutic approaches for cancer and intense interest in the development of second-generation epigenetic drugs (epi-drugs) which would have greater specificity and efficacy in clinical settings. The latest developments in this exciting arena of translational cancer epigenetics were presented at a recent conference on “Epigenetics and New Therapies in Cancer” at the Spanish National Cancer Research Center (CNIO), Spain.

Genomic imprinting attracted particular attention in the 1980’s following the discovery that the parental origin of genetic information is essential for normal development of eutherians,1,2 for review see.3 The term imprinting was first introduced in the 1960s to describe the elimination of the paternal chromosomes during spermatogenesis in the Sciarid fly.4‑6Today the term genomic imprinting mainly refers to parent‑of‑origin specific effects distinguishing each parental genome which can be regarded as memories, or “imprints”.7,8 Breaking the rules of Mendel, genomic imprinting is an epigenetic phenomenon per se. Epigenetics is currently defined as the study of mitotically or meiotically heritable changes in gene expression without any change in DNA sequence9,10 and it is intimately linked to the study of inheritance of chromatin states.11 Gene imprinting currently refers to differential expression of autosomal genes according to their parent of origin.12The phenomenon of genomic imprinting explains several cases of parent‑specific human disorders.13 To date over 80 imprinted genes have been described in mammals14 and their parent‑of‑origin specific expression can correlate with changes in DNA methylation patterns, antisense noncoding RNAs and chromatin folding.3 Epigenetic imprints can either activate or silence the “imprinted” allele, and hence imprinting can be associated with either an expressed or silenced allele.15 In mammals, the number of paternally expressed imprinted genes is almost equivalent to the number of maternally expressed genes and the imprinted status can differs according to tissue, developmental stage and species. It is then crucial for our understanding to clearly indicate the status of imprinting (i.e., paternally or maternally expressed) and the context (e.g., species, developmental stage, tissue).

The evolutionary origin of double fertilization and the resultant endosperm tissue in flowering plants remains a puzzle, despite over a century of research. The recent resurgence of approaches to evolutionary developmental biology combining comparative biology with phylogenetics provides new understanding of endosperm origins.

Genomic imprinting allows parent-of-origin specific control over gene expression. Although imprinted genes (or entire chromosomes) are homologous sequences that can be inherited from either parent, they are differentially marked by a heritable epigenetic modification (imprint), which can condition their behavior in term of gene expression. Imprinting-based regulation of entire chromosomes is observed in both insects (paternal genome elimination) and mammals (nonrandom X inactivation). Until recently, it was unknown whether plants possessed a similar epigenetic system discriminating between homologous chromosomes from either paternal or maternal origin. There is now experimental evidence for a genome-wide imprinting phenomenon during seed development in Arabidopsis. Genomic imprinting at the gene (or locus) level is observed in both mammals and flowering plants. In maize, only a few allelic variants of several nonessential genes expressed in the endosperm are imprinted. In Arabidopsis, gene-specific imprinting has recently been demonstrated for the MEDEA(and FIS2) gene, which is essential for normal seed development. Unlike the imprinted maize genes, so far all tested MEAalleles are subjected to regulation by imprinting. MEDEAand FIS 2are members of the FISclass of genes (FERTILIZATION INDEPENDENT SEED) involved in regulation of growth and cell proliferation during seed development. MEDEAshares several paradigmatic features with imprinted mammalian genes. The MEDEAphenotypes provide empirical support for theories of an intragenomic parental conflict during seed development, whereby imprinting is proposed as a means to differentially balance the selfish interests of each sex's genome during the development of the progeny.

A line of transgenic tobacco expressing the coat protein (CP) of potato virus X (PVX) was resistant against a broad spectrum of PVX strains. Inoculation of leaves and protoplasts with PVX expressing the jellyfish green fluorescent protein reporter gene revealed that this resistance mechanism suppressed PVX replication in the initially infected cell and systemic spread of the virus. Cell-to-cell movement was also slower in the resistant plants. The resistance at the level of replication was effective against wild-type PVX and also against movement-defective isolates with a frameshift mutation or deletion in the CP ORF. However, the cell-to-cell movement defect of the mutant viruses was rescued on the resistant plants. Based on these results it is proposed that the primary resistance mechanism is at the level of replication.

•We assess the perspectives of both women and men regarding acquisition of CCS.•Men report low motivation for acquiring CCS, in sharp contrast to women.•Men however possess the final decision-making authority on acquisition of CCS.•Cookstove programs that overlook the important role of men are unlikely to succeed.