The study modeled the yield stability of selected early- and medium-duration cowpea genotypes across six locations in northern Ghana to identify the most stable and winning genotype(s). The models employed in the study included a combined analysis of variance (ANOVA), the Additive Main Effects and Multiplicative Interaction (AMMI) model, the Genotype + Genotype-by-Environment (GGE) biplot model, and non-parametric statistical models. The yield stability and adaptability measure SARI-2-50-80 indicated that the genotypes SARI-2-50-80, IT86D-610, IT10K-837-1, and SARI-6-2-6 are high-yielding and stable among medium-duration cowpea lines across environments. The study also found that genotypes SARI-3-11-80 (0.227 t/ha) and the checker cultivar KIRKHOUSE-BENGA (0.145t/ha) had relatively lower ASV (AMMI Stability Value) values, indicating higher stability in medium-duration cowpea lines. Genotypes SARI-3-11-80 (0.0696t/ha) and SARI-1-3-90 (0.0952t/ha), SARI-13-17-2 and IT07K-299-6IT07K-299-6, demonstrated lower MASI (Mean Absolute Standard Index) values, suggesting higher stability and adaptability. Genotypes SARI-3-11-80 (0.442t/ha) and KIRKHOUSE-B (0.581 t/ha) exhibited relatively lower MASV (Mean Absolute Standard Values /Modified AMMI stability Value)) values, indicating higher stability and adaptability. Damongo, Yendi, and Manga were identified as the most promising environments for most of the lines. Yield stability was significantly predicted by genotype, environment and genotype by environment interactive effect. The ANOVA for confirmation, AMMI and GGE for decomposition and visualization, and non-parametric models for robust validation represent a highly accurate and comprehensive approach to MET (Multi-Environment Trial) analysis. The AMMI model derived the calculated stability metrics which were used for the accurate identification of the high-yielding and stable genotypes.
Sorghum is a vital crop, especially in drier tropical regions, where it supplies the daily caloric needs for people. However, the productivity and profitablity of crop are hampered by several biotic stresses, including grain mold. Grain mold disease complex is associated with several fungal genera, including those that are mycotoxigenic. The aim of this research was to compare grain mold severity, 100-seed weight, germination rate, and mycoflora of seeds collected from non-commercial and commercial sorghum fields in Burleson County, Texas, Grain mold severity was based on a scale of 1-5, germination rate was based on the percentage of 100-seeds per replicate, and identification of the fungal species under microscope was based on the conidia, conidiophores, colony morphology, and color. Overall, seeds collected from commercial fields exhibited lower grain mold severity and higher seed weight, while seeds from non-commercial fields had higher percent germination rates. The mycoflora analysis of seeds obtained from both non-commercial and commercial fields revealed the occurrence of many microorganisms, as: Alternaria alternata, Bipolaris spp., Curvularia lunata, Aspergillus niger, Colletotrichum sublineola, and other unidentified fungal species and bacterial strains. All identified microorganisms except for A. niger were detected in samples from non-commercial and commercial fields; A. niger (1%) was only recovered from non-commercial fields., In conclusion, lower grain mold infection and higher seed weight were observed in commercial fields when compared to non-commercial or research plots, while percent seed germination rate was higher in non-commercial fields.
Sorghum, a multipurpose and drought-tolerant crop, will play an integral role in future food security, especially in the drier tropics. In Niger and Senegal, sorghum supplies the daily caloric needs of millions of inhabitants. One of the major constraints to sorghum production is downy mildew incited by Peronosclerospora sorghi. In this communication, we report the results of a genome-wide association study (GWAS) of a subset of the 120 accessions from Niger and Senegal for downy mildew response under natural infection. The GWAS revealed several loci that have already been reported for their role in plant disease resistance response. Significant SNPs identified on chromosomes 1 and 5 traced back to genomic regions neighboring loci coding for transcription factors involved in biotic stress response. On chromosome 4, the SNP identified was less than 5 kb apart from a gene coding for an E3 ubiquitin ligase enzyme that regulates gene expression levels in relation to plant disease resistance. A membrane-bound protein involved in programmed cell death on chromosome 6 and a transposase on chromosome 8 were identified. Furthermore, a SNP locus that has not been reported previously for biotic stress response was also identified on chromosome 10. This SNP was 4.94 kb downstream of Sobic.010G172100, which encodes a protein similar to the basic helix-loop-helix (bHLH) transcription factor. bHLHs are known for their role in abiotic stress responses. Further work to validate and confirm the activities of the identified SNPs in resistance response will be conducted.
Poor soil fertility is a problem for agriculture in Burkina Faso. Litterfall is an important way for bio-elements to return to the soil. Therefore, the dynamics and quantity of litterfall were studied as part of a collaborative research project that aims to better manage agroforestry parkland. Five 0.25 m2 litter traps were placed under 5 trees of 3 species (Vitellaria paradoxa, Lannea microcarpa and Parkia biglobosa) that have multiple purposes in agroforestry. Every 2 weeks, litter was collected and sorted into leaves, twigs, fruits and other non-foliar components, which were oven dried and weighed. We calculated total annual litter production by species and fractions. Afterwards, Vitellaria paradoxa, Lannea microcarpa, and Azadirachta indica litterfall and Sorghum crop residues were composted and the chemical qualities of the composts were compared. Mean total litterfall (±SE) was 689±94, 671±141, and 1435±190 g dw m-2 yr-1 for L. microcarpa, Parkia biglobosa, and V. paradoxa, respectively. Leaf litter component composition varied from 47% to 87% depending on species. The largest littefall input occurred in the dry season, October–April. Litter quantity showed that agroforestry parkland is productive. Litterfall composts had better chemical quality than conventional crop residue compost, but the decomposition rate of V. paradoxa litter was very low (29%). These results suggest that with proper management, litterfall could contribute significantly to enhancing soil fertility in agroforestry parkland.
Vouarana hispaniolae (Sapindaceae) is described as a new fossil flower in Dominican Republic amber. The flower is functionally staminate and is characterized by an actinomorphic corolla with 5 distinct, imbricate sepals that are ciliate on their margins, and closely appressed to surface of the receptacle; petals presumable 5, two partly visible are rhombic to triangular in shape; stamens 8, outstretched, filaments bearing thick setae at base; anthers square, basifixed, some retuse at apex, dehiscing via longitudinal slits, central pistillode short, setose; extra-nectary disc entire; pollen trigonous, glabrous and smooth. The fossil species differs from the two extant species of Vouarana that range from Costa Rica to northern Brazil by possessing a uniform covering of bristly setae over the entire receptacle, appressed sepals and square basifixed anthers. This specimen represents the first fossil flower of the Sapindaceae from the Neotropics.
