In vitro Regeneration and Proliferation of Maize (Zea mays L.) Genotypes through Direct Organogenesis

The variability of in vitro regeneration and proliferation of maize genotypes POOLISSRQPMX, DTSR-WCO, TZLCOMP4C3, TZE COMP 3C2, EV99QPM, POP66 SR/ACR94-YQPM, DTSR-WC, SAMMAZ 19S-14DT and TZEE-YPOPSTRC4 was investigated. Explants were regenerated through direct organogenesis using 0.1 mg/l NAA + 2.0 mg/l BAP, 0.1 mg/l NAA + 2.0 mg/l KIN, 0.3 mg/l NAA + 3.0 mg/l BAP, 0.3 mg/l NAA + 3.0 mg/l KIN, 0.5 mg/l NAA + 4.0 mg/l BAP, 0.5 mg/l NAA + 4.0 mg/l KIN and MS medium only. The regenerated maize yielded the highest number of multiple shoots (1.70 cm) and shoot length (3.35 cm) on MS medium supplemented with 0.3 mg/l NAA + 3.0 mg/l BAP within 31 days. Genotype EV99QPM and DTSR-WCO had the highest number of shoots, rooting traits respectively. Keywords: Maize, regeneration, hormones, variability, survival, character DOI: 10.7176/JNSR/9-6-09 Publication date:March 31st 201

Trenchant microbiological-based approach for the control of Striga: Current practices and future prospects

Striga species are obligate parasitic weeds most of which are members of the Orobanchaceae family. They are commonly associated with staple crops and constitute threats to food security, especially in Sub-Saharan Africa. They pose deleterious impacts on staple cereal crops like maize and pearl millet, resulting in 7–10 billion dollars yield losses or, in extreme infestations, entire crop losses. Farmers' limited knowledge about the weed (genetics, ecology, nature of the damage caused, complex life cycle, interactions with its host and associated microbes) and their attitude toward its control have negatively affected its management and sustainability. With the present Striga management such as mechanical, chemicals, cultural and biological measures, it is extremely difficult to achieve its active management due to nature of the association between host plants and parasites, which requires highly selective herbicides. The use of soil microbes has not been well explored in the management of Striga infection in African countries. However, many soil microorganisms have been considered viable biological control techniques for fighting parasitic weeds, due to their vast action and roles they play in the early stage of host-Striga interaction. Their application for pest control is well perceived to be cost-effective and eco-friendly. In this review, we gave a comprehensive overview of major knowledge gaps and challenges of smallholders in Striga management and highlighted major potentials of microbial-based approach with respect to the mechanisms of host-Striga-microbe interactions, and the metagenomics roles on Striga management that include understanding the microbe and microbial systems of Striga-infested soil

Shotgun metagenomics dataset of Striga hermonthica-infested maize (Zea mays L.) rhizospheric soil microbiome

This dataset includes shotgun metagenomics sequencing of the rhizosphere microbiome of maize infested with Striga hermonthica from Mbuzini, South Africa, and Eruwa, Nigeria. The sequences were used for microbial taxonomic classification and functional categories in the infested maize rhizosphere. High throughput sequencing of the complete microbial community's DNA was performed using the Illumina NovaSeq 6000 technology. The average base pair count of the sequences were 5,353,206 bp with G+C content of 67%. The raw sequence data used for analysis is available in NCBI under the BioProject accession numbers PRJNA888840 and PRJNA889583. The taxonomic analysis was performed using Metagenomic Rapid Annotations using Subsystems Technology (MG-RAST). Bacteria had the highest taxonomic representation (98.8%), followed by eukaryotes (0.56%), and archaea (0.45%). This metagenome dataset provide valuable information on microbial communities associated with Striga-infested maize rhizosphere and their functionality. It can also be used for further studies on application of microbial resources for sustainable crop production in this region

Role of arbuscular mycorrhizal fungi as biocontrol agents against Fusarium verticillioides causing ear rot of Zea mays L. (Maize)

The protection of plants from pathogens results to better performances in growth and yield characters. Therefore, the efficacy of Glomus clarum and G. deserticola as biocontrol agents against Fusarium verticillioides (AKR 05, ILR 06 and ERW 05) strains on maize T2L COMP.4 was investigated. Concentration 10 g (20 spores), 20 g (48 spores) and 30 g (72 spores) of Glomus clarum and G. deserticola were inoculated separately into 8 kg of soil at four weeks after planting (WAP), with a control (0 g). In addition, spore suspension (1.0 × 106 spores/mL) of Fusarium verticillioides was inoculated at 8 WAP. The treatments were arranged in a completely randomized design with three replicates. The pathogenic effects of F. verticillioides on plant height and shoot weight were significantly reduced by the application of 20 g of G. clarum and 30 g of G. deserticola. Also, 10 g of both G. clarum and G. deserticola significantly enhanced the production of the husk cover, while 30 g G. clarum and G. deserticola significantly reduced the severity of maize ear rot. Therefore, 30 g G. clarum and G. deserticola had biocontrol potential against Fusarium verticillioides. Hence, they are recommended to maize producers in Fusarium endemic agro-ecological zones for optimal production. Keywords: Biocontrol, Concentration, Disease severity, Glomus clarum, Spore suspensio

Bioresources in Organic Farming: Implications for Sustainable Agricultural Systems

Over the years, the practice of agriculture has transformed from the era of traditional to that of intensive agriculture in the bid to boost the production index that will satisfy the food needs of the globally growing population. However, the continuous and exaggerated use of chemical fertilizers and pesticides has resulted in major adverse impacts on food and environmental safety, whereas most traditional techniques for reclamation of natural soil nutrients, including shifting cultivation and polyculture, are no longer attractive measures of land rejuvenation. There is, therefore, the need for urgent evaluation and adoption of innovative methods of replenishing the agricultural soils that conform to the current agricultural systems without exerting undesirable effects on the ecosystem. In this review, we elucidated the use of key bioresources, such as organic fertilizers, biofertilizers, and biopesticides, as alternatives to chemical-based products in attaining a safe and sustainable agricultural system. Bioresources are naturally available, safe, and easily accessible products. The potential of these biological products in fostering soil microbial growth, plants’ productivity, and induced host immunity to diseases, alongside the promotion of healthy soil–microbe–plant relationships and preservation of the ecosystem processes without disruption, are aspects that were also explored. Therefore, the productive use of bioresources is considered strategic as it pertains to attaining safe and sustainable food production