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Cowpea is one of the most important leguminous crops in Sub-Saharan Africa (SSA), and moisture stress is among the constraints affecting its productivity. This study was conducted to understand the response of cowpea accessions to moisture stress. A total of 255 cowpea accessions from Togo and four checks from the International Institute of Tropical Agriculture (IITA), were assessed. The trials were conducted in the glasshouse and an open field (which was divided into moisture-stressed (MS) and non-moisture-stressed fields (NMS)). In the non-moisture-stressed environment compared to the moisture-stressed environment, there was a greater heritability for agronomic traits such as biomass, seed weight, and pod weight. The accessions with the highest seed weights (yield-related traits), surpassing the checks under both moisture-stressed and non-moisture-stressed conditions in the field, were six viz.: RK173 (49.8 g (MS); 90.4 g (NMS)), RP225 (34.6 g (MS); 119.9 g (NMS)), RP232 (33.4 g (MS); 51.9 g (NMS)), RM357 (27.9 g (MS); 62.9 g (NMS)), RK148 (23.9 g (MS); 63.4 g (NMS)), and Vu081_2_2 (21.8 g (MS); 46.7 g (NMS)). The most promising accession was RK173; this was ranked first under the moisture-stressed condition and ranked second under the non-moisture-stressed condition with a loss in weight of 44.9% due to drought stress. Of the top 20 accessions that recovered after watering resumed in the glasshouse screening, only the following 9 had a recovery percentage higher than 5% viz.: RS029 (34.5%), RK014 (14.2%), RS114 (9.6%), RK121 (8.3%), RS007 (7.6%), RK123 (7.3%), RS037 (7.3%), RS101 (5.6%), and RS108 (5.1%). The best line and those with a higher recovery percentage could be exploited further in order to improve them in future drought breeding programs by crossing them with lines susceptible to drought or using other drought breeding techniques.

Probiotics and related preparations, including synbiotics and postbiotics, are living and non-living microbial-based multi-components, which are now among the most popular bioactive agents. Such interests mainly arise from the wide range and numerous beneficial effects of their use for various hosts. The current minireview article attempts to provide an overview and discuss in a holistic way the concepts, methodologies, action mechanisms, and applications of probiotic-based multi-components in human, animal, plant, soil, and environment health. Probiotic-based multi-component preparations refer to a mixture of bioactive agents, containing probiotics or postbiotics as main functional ingredients, and prebiotics, protectants, stabilizers, encapsulating agents, and other compounds as additional constituents. Analyzing, characterizing, and monitoring over time the traceability, performance, and stability of such multi-component ingredients require relevant and sensitive analytical tools and methodologies. Two innovative profiling and monitoring methods, the thermophysical fingerprinting thermogravimetry–differential scanning calorimetry technique (TGA-DSC) of the whole multi-component powder preparations, and the Advanced Testing for Genetic Composition (ATGC) strain analysis up to the subspecies level, are presented, illustrated, and discussed in this review to respond to those requirements. Finally, the paper deals with some selected applications of probiotic-based multi-components to human, animal, plant, soil and environment health, while mentioning their possible action mechanisms.

The development of maize varieties with increased concentration of Provitamin A (PVA) is an effective and affordable strategy to combat vitamin A deficiency in developing nations. However, the considerably high cost of carotene analysis poses a major challenge for maize PVA biofortification, prompting the use of marker-assisted selection. Presently, two types of genotyping with PVA trait-linked functional markers have been developed and extensively used in breeding programs. The two systems are low throughput gel-based genotyping and genotyping with Kompetitive Allele-Specific PCR (KASP) single nucleotide polymorphism (SNPs) markers. Although the KASP SNPs genotyping was developed to replace the gel-based genotyping, studies have not been conducted to compare the effectiveness of the KASP SNPs markers with the gel-based markers. This study was conducted to assess the carotenoid content of 64 tropical PVA biofortified maize inbred lines containing temperate germplasm in their genetic backgrounds and screen them with both gel-based and KASP markers of PSY1, LCYE and crtRB1 genes. Many of the 64 inbred lines had PVA concentrations surpassing the 15 µg/g provitamin A breeding target set by the HarvestPlus Challenge Program. Favorable alleles of crtRB1, crtRB1 and the KASP SNPs markers were detected in 25 inbred lines with high PVA concentrations. Inbred lines with the favorable alleles of LCYE had the highest concentrations of non-PVA carotenoids, whereas those with the favorable alleles of crtRB1 had high levels of PVA carotenoids. Data from the sequenced region of LCYE revealed one SNP in the first intron that clearly differentiated the high and low β-carotene maize inbred lines. The results of our study demonstrate that the automated KASP SNPs markers can replace the gel-based genotyping for screening a large number of early generation maize inbred lines for PVA content.

A hemiparasitic plant, Striga hermonthica (Del.) Benth and soil nitrogen stress are the key constraints to maize (Zea mays L.) productivity in sub-Saharan Africa, where commonly cultivated maize is the normal endosperm type that is deficient in provitamin A, tryptophan and lysine (PVATL). Seventy-six extra-early maize inbreds with provitamin A, tryptophan, and lysine qualities (TZEEIORQ) were developed to address these constraints, and four checks were assessed under Striga, low and high nitrogen conditions at three locations in Nigeria. The inbreds were further genotyped with two beta-carotene hydroxylase 1 (crtRB1) markers, and their seeds were quantified for provitamin A content. Significant (p < 0.01) genetic variations were observed for grain yield and other agronomic attributes of the inbreds under varying environmental conditions. Levels of PVATL for the inbreds ranged from 2.21–10.95 µg g−1, 0.04–0.08%, and 0.19–0.39%, respectively. Beta-carotene marker, crtRB1-3′TE, was polymorphic and grouped the inbreds into two. The marker was effective in identifying inbreds with moderate provitamin A content. Inbreds TZEEIORQ 5, TZEEIORQ 52, and TZEEIORQ 55 exhibited resistance to Striga, tolerance to nitrogen stress with moderate levels of PVATL and could be invaluable sources of favorable alleles for breeding nutritionally improved maize varieties with resistance/tolerance to Striga and soil nitrogen stress.

This study determined the gene effects involved in the inheritance of pod length and other yield-related traits and relationships among traits in crosses between two cowpea lines (TVu 2280 and TVu 2027) and a yard-long bean (TVu 6642) line with long pods. Plants of six generations (P1, P2, F1, F2, BC1P1, and BC1P2) derived from TVu 2280 × TVu 6642 and TVu 2027 × TVu 6642 were evaluated under field conditions. Data collected on 14 yield components of each cross were used for generation mean analysis. Gene effects and their magnitudes varied with the crosses; digenic epistatic gene effects were detected for 10 traits in TVu 2280 × TVu 6642 and 11 traits in TVu 2280 × TVu 6642. Only additive gene effect was significant for pod length in TVu 2280 × TVu 6642 while additive, dominant, and two of the three digenic epistatic gene effects were significant in TVu 2027 × TVu 6642. Models that incorporated only significant additive, dominant, and digenic epistasis were adequate for all 14 traits in TVu 2280 × TVu 6642 and eight of the 12 traits in TVu 2027 × TVu 6642 for which model-fitting was possible. Across segregating generation of the two crosses, pod length (PodLNT) was significantly (p < 0.001) correlated with three major yield components viz. pod weight (0.84, 0.77), number of seeds per pod (0.41, 0.30) and seed weight per pod (0.61, 0.29). Significant correlation of PodLNT with seed yield per plant was moderate and significant (p < 0.01–0.001) in the BC1P1 of the two crosses (0.31 and 0.41). An improvement in cowpea seed yield is feasible through selection for long pods in segregating generations involving crosses with yard-long bean.

Maize streak virus (MSV) is responsible for streak disease of maize and poses a serious threat to maize production in sub-Saharan Africa. Polygenic resistance to MSV has become an essential requirement in modern maize cultivars to mitigate yield losses. Many single nucleotide polymorphism (SNP) markers linked to putative MSV resistance loci have been identified for use in forward breeding. This study aimed to validate, using the high-throughput kompetitive allele specific PCR (KASP) assay, the diagnostic ability of the three SNP markers linked to the loci for the Msv1 resistance trait in 151 early generations inbred lines with diverse genetic backgrounds, together with nine MSV-resistant elite lines and a susceptible check (cv. Pool-16). The phenotypic responses were determined by MSV inoculation using viruliferous leafhoppers (Cicadulina triangular) under screenhouse conditions. Based on an established MSV disease rating system, the maize lines were categorized into resistant, moderately resistant, susceptible, and highly susceptible. The three SNPs associated with MSV resistance were detected in 133 lines, which were categorized as resistant (54), moderately resistant (76), and susceptible (1). The 18 early generation lines without these SNPs were classified as moderately resistant (10), susceptible (5), and highly susceptible (3). This study confirms the strong association of SNPs with MSV resistance and their usefulness for forward breeding in maize while emphasizing the need to identify additional markers to screen lines for MSV resistance without any ambiguity.