Finger millet (Eleusine coracana (L.) Gaertn. subsp. coracana) is the most important millet in eastern Africa and perhaps the oldest domesticated cereal grain in Africa. One of the major factors limiting finger millet production is blast disease caused by the fungus Magnaporthe grisea. Crop wild relatives and landraces present a potential source of novel genes. This study investigated the response of cultivated and wild relatives of finger millet to an isolate of blast disease from western Kenya. Previous germplasm collections were purified through two generations of single‐seed descent before screening alongside improved and farmer‐preferred varieties (FPVs) under a screen house across three seasons. Farmer‐preferred varieties were identified through participatory varietal selection (PVS). The plants were inoculated twice during each growth period using hand‐spraying method and data on disease incidence recorded at grain‐filling stage. Genotypic data was generated using diversity arrays technology (DArT) sequencing and data analysis done using Genstat 18.2 and TASSEL 5.2.58. We observed high heritability (81%), indicating that the variation observed was predominantly genetic. Wild accessions were generally more resistant to the disease in comparison to the cultivated accessions. Preliminary genome‐wide association study (GWAS) using general linear model with principal component analysis led to the identification of 19 markers associated with blast disease that will be be developed into assays for genotype quality control and trait introgression. Wild accessions and landraces of finger millet present a good reservoir for novel genes that can be incorporated into crop improvement programs.
Finger millet is a key food security crop widely grown in eastern Africa, India and Nepal. Long considered a ‘poor man’s crop’, finger millet has regained attention over the past decade for its climate resilience and the nutritional qualities of its grain. To bring finger millet breeding into the 21st century, here we present the assembly and annotation of a chromosome-scale reference genome. We show that this ~1.3 million years old allotetraploid has a high level of homoeologous gene retention and lacks subgenome dominance. Population structure is mainly driven by the differential presence of large wild segments in the pericentromeric regions of several chromosomes. Trait mapping, followed by variant analysis of gene candidates, reveals that loss of purple coloration of anthers and stigma is associated with loss-of-function mutations in the finger millet orthologs of the maize R1/B1 and Arabidopsis GL3/EGL3 anthocyanin regulatory genes. Proanthocyanidin production in seed is not affected by these gene knockouts.
Sorghum (Sorghum bicolor [L.] Moench) is the fifth most important cereal crop worldwide and second after maize (Zea mays L.) in Kenya. It is an important food security crop in arid and semi-arid lands, where its production potential is hampered by drought. Drought tolerance can be measured by a plant's ability to resist premature senescence, often described as stay-green. This study was carried out with the objective of identifying novel stay-green trait among wild and landrace genotypes of sorghum. Forty-four sorghum genotypes that included 16 improved, nine landraces, and 17 wild relatives of sorghum alongside known stay-green sources, B35 and E36-1, were evaluated under well-watered and water-stressed conditions in an alpha-lattice design of three replications. Data was collected on plant height (PHT), flag leaf area (FLA), panicle weight (PWT), 100-seed weight (HSW), relative chlorophyll content (RCC), number of green leaves at maturity (GLAM), days to 50% flowering (DFL), and grain yield (YLD). Genetic diversity was determined using diversity arrays technology (DArT) sequencing and quality control (QC) markers were generated using a java script. Lodoka, a landrace, was the most drought-tolerant genotype, recorded the highest numbers of RCC and GLAM, and outperformed B35 and E36-1 in yield under water-stress and well-watered conditions. The RCC was highly correlated with GLAM (r = .71) and with yield-related traits, HSW (r = .85), PWT (r = .82), and YLD (r = .78). All traits revealed high heritability (broad-sense) ranging from 60.14 to 98.4% for RCC and DFL, respectively. These results confirm earlier reports that wild relatives and landraces are a good source of drought tolerance alleles.
Agricultural conversion of tropical forests is a major driver of biodiversity loss. Slowing rates of deforestation is a conservation priority, but it is also useful to consider how species diversity is retained across the agricultural matrix. Here we assess how bird diversity varies in relation to land use in the Taita Hills, Kenya. We used point counts to survey birds along a land-use gradient that included primary forest, secondary vegetation, agroforest, timber plantation and cropland. We found that the agricultural matrix supports an abundant and diverse bird community with high levels of species turnover, but that forest specialists are confined predominantly to primary forest, with the matrix dominated by forest visitors. Ordination analyses showed that representation of forest specialists decreases with distance from primary forest. With the exception of forest generalists, bird abundance and diversity are lowest in timber plantations. Contrary to expectation, we found feeding guilds at similar abundances in all land-use types. We conclude that while the agricultural matrix, and agroforest in particular, makes a strong contribution to observed bird diversity at the landscape scale, intact primary forest is essential for maintaining this diversity, especially among species of conservation concern. Chalcomitra amethystina Amethyst sunbird NECT. f Cinnyris mediocris Eastern double-collared sunbird NECT. F Cinnyris venustus Variable sunbird NECT. f Cyanomitra olivacea Olive sunbird NECT. FF Phylloscopus ruficapilla Yellow-throated woodland warbler INSECT. FF Phylloscopus trochilus Willow warbler INSECT. f Pycnonotus barbatus Common bulbul FRUG. f Andropadus importunus Sombre greenbul FRUG. f
Intercrop breeding programs using genomic selection can produce faster genetic gain than intercrop breeding programs using phenotypic selection. Intercropping is an agricultural practice in which two or more component crops are grown together. It can lead to enhanced soil structure and fertility, improved weed suppression, and better control of pests and diseases. Especially in subsistence agriculture, intercropping has great potential to optimise farming and increase profitability. However, breeding for intercrop varieties is complex as it requires simultaneous improvement of two or more component crops that combine well in the field. We hypothesize that genomic selection can significantly simplify and accelerate the process of breeding crops for intercropping. Therefore, we used stochastic simulation to compare four different intercrop breeding programs implementing genomic selection and an intercrop breeding program entirely based on phenotypic selection. We assumed three different levels of genetic correlation between monocrop grain yield and intercrop grain yield to investigate how the different breeding strategies are impacted by this factor. We found that all four simulated breeding programs using genomic selection produced significantly more intercrop genetic gain than the phenotypic selection program regardless of the genetic correlation with monocrop yield. We suggest a genomic selection strategy which combines monocrop and intercrop trait information to predict general intercropping ability to increase selection accuracy in early stages of a breeding program and to minimize the generation interval.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.