The global use of glyphosate-based herbicides (GBHs) and release of glyphosate residues in soil environment have over the years been a major concern. In this study, we aim to evaluate the biochemical response and vermiremediation potential of three indigenous earthworm species; namely Alma millsoni, Eudrilus eugeniae and Libyodrilus violaceus in GBH treated soils. Study design: Three weed plants (Tridax procumbense, Ludwigia pasturis and Pannicum maximum) were transplanted into 140 plastic pots and 20 adult individual earthworms of each species were later introduced into 60 pots. In total, each earthworm species treatments representing 20 pots and 20 pots without earthworm were sprayed with 115.49 mL/m 2 (equivalent to 83.2 g a.i/m 2) of Roundup® Alphée. The remaining 60 pots with earthworm species were left unsprayed. Activities of glutathione-S-transferase (GST), lactate dehydrogenase (LDH), metallothionine (MT), acetylcholinesterase (AChE), antioxidant defense system and lipid peroxidation (MDA) were monitored at the 1st, 2nd, 4th, 6th and 8th weeks Post Herbicide Application (PHA) using standard methods. Glyphosate residues in the soil and earthworm species were quantified with a High-Performance Liquid Chromatography (HPLC) with fluorescence detector. Bioaccumulation Factor (BAF) was also calculated. Results: Higher activities of GST and LDH and reduction in MT activities were observed in the three earthworm species exposed to GBH compared to the unexposed while AChE activity was insensitive to the herbicide. The antioxidant defence system was able to protect E. eugeniae and L. violaceus against oxidative stress. The presence of earthworms reduced glyphosate residues in the soil. E. eugeniae and L. violaceus were bioaccumalators and biomagnifiers of glyphosate as indicated by the BAF (> 1) obtained after 8th week PHA. Relationships exist between glyphosate BAF in E. eugeniae and L. violaceus and exposure duration as well as between glyphosate residues in tissues of the earthworm species and their biochemical parameters. Conclusions: Alterations in the enzymatic activities and antioxidant defence of the earthworm species could be an index for GBH contaminated soil monitoring and assessment; both E. eugeniae and L. violaceus showed potential to vermiremediate soils contaminated with GBH.

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Tomato (Solanum lycopersicum L.) is a broadly consumed fruit vegetable globally. It is one of the research mandate vegetable of the National Horticultural Research Institute (NIHORT), Ibadan, Nigeria. The institute’s contains diverse collections of tomato accessions and wild relatives, without utilization information for the African continent. With the decline in diversity and potential of cultivars, a robust tomato breeding pipeline with broad genetic base that eliminates redundancy in the development of lines with desired horticultural traits is paramount. This study evaluated the mean performance and variations of thirteen wild tomato accessions obtained from the C.M. Rick Tomato Genetic Resource Center, University of California, Davis, USA, evaluated for agronomic, nutritional and physicochemical traits under a rain forest zone in Nigeria. The accessions were planted and grown in three replications with randomized complete block design. Agronomic traits, physicochemical and nutritional parameters were measured and analyzed. There was significant (P < 0.001) variation among accessions for all traits measured. Accession LA0130 was separated from others by cluster analysis and was outstanding for its unique attributes which include: fruit yield parameters, total soluble solids, acidity and content. The principal component analysis suggests fruit yield related traits, acidity and contributed most to the variation among the 13 accessions. The results obtained can be used to breed materials adapted to a rain forest . These wild tomato accessions have genes with desirable agronomic, nutritional and physicochemical traits that could be into breeding lines to improve commercial tomato varieties.

Salicylic acid (SA) a signal molecule which is responsible for inducing defense mechanisms in plants and also has a protective role in stress sensitivity. A study was conducted to determine the effect of water deficit stress on the growth of Lactuca sativa L. (Lettuce) using SA (1 mM and 3 mM) during reduced leaf water potential. Plants were subjected to 7 days drought after four weeks of growth. Stressed plants exhibited a lower leaf water potential (ψw) of -0.499 MPa as compared with the control (ψw of -0.460 MPa). Plants with lower leaf ψw exhibited reduction in almost all the parameters studied: 1 mM SA foliar treatment caused increase of 8 % in plant height and 53.16 % in plant biomass. Foliar treatment of 3 mM SA of the relative water content stimulated 13 % increase in the growth as compared to the control plant which was statistically significant at P<0.05. Overall, SA in stressed plant exhibited higher ameliorative capacity which has the beneficial role of mediating defense response in plants under stress.

The Lagos-Ibadan Expressway is the busiest inter-state route in Nigeria and one of the largest road networks in Africa. It handles more than 250,000 PCUs (Passenger Car Units) daily. Amount of metal emissions being released daily from vehicles plying this road into the environment (air, soil, plant and water) is great! This study evaluated heavy metal composition in soils resulting from exhausts pollution from vehicular movement along Lagos-Ibadan Expressway. A total of two hundred and seventysix soil samples were collected at 5, 15 and 25 m away from the edge of the road. The soil samples were collected with hand auger from the surface to a depth of 10 cm during both dry and wet seasons. Heavy metal concentrations were determined using Atomic Absorption Spectrophotometer (AAS). The heavy metal concentrations found in sampled soil during dry season in mg.kg -1 along the study sites revealed the following,