Biology subjects

Ikhajiagbe, B.

Publications and source records attributed to Ikhajiagbe, B..

6 recordsLinked to original sources

bioRxiv2021

Genetic diversity assessment of neem (Azadirachta indica A. Juss) in northern Nigeria

Neem is a tropical tree that can adapt to a wide range of places and particularly to semi-arid conditions. As at present, it is grown in many Asian countries and also in the tropical regions of the western hemisphere. Genetic variability and diversity are a major requirement needed for both immediate results and the one ones thereafter adaptation of plant types in their original domain. The evaluation of genetic diversity of any species is extremely crucial for their sustainability, continuity, survival and gene manipulation. Major breakthroughs in the field of molecular biology was able to develop several tools for the investigation of genetic diversity at the genome level to determine phylogenetic relationships among inter or intra-species. The advent of molecular markers for the detection and exploitation of DNA polymorphism is one of the major breakthroughs in the world of molecular genetics. The importance of genetic diversity in plant germplasm conservation, especially in economically important species such as Azadirachtaindica, is enormous, particularly in Nigeria. The question is whether A. indica from different Agro-ecological zones have genetic variations or similarities. This was the bane of the current study, which used RAPD to look atgenetic diversity of 27 randomly selected neem trees within the agro-ecological zones in Northern Nigeria. A total of 9 primers were employed out of which only 5 were responsive (OPA-02, OPA-03, OPA-15 and OPA-19). These primers showed dissimilarities in the visible DNA bands among the various tree samples. There was evidence of genetic dissimilarities among the trees sampled. Differences in percentage polymorphism was reported, where it was reportedly highest among the Borno State tree samples (97.44%), compared to those in Yobe State with no polymorphism.

plant biology↗

bioRxiv2021

Influence of selected plant growth stimulators in enhancing germinability and germination parameters of Zea mays L. under microgravity conditions simulated by a two-dimensional clinostat

The earth has become increasingly overcrowded as a result of rapid urbanization and population growth, predicting that its carrying capacity could be overstretched. As a result, it is important to test the possibilities of growing plants under space exploration conditions, especially gravitational balance. Since microgravity impedes plant development, to what extent can plant growth stimulators reverse or enhance this trend? A total of 12 maize seeds were weighed and placed sideways in petri dish and inoculated with plant growth stimulators such as indole acetic acid (IAA), gibberellic acid (GA), and ascorbate (AA) and the clinorotated at different rates (0.5, 1.0 and 2.0 rpm), while control seeds were just placed on a table. Results showed that at 72 hrs, the maize seeds under microgravity showed reduced germination percentage with increasing clinorotation rates as against the control. But when stimulated with IAA, GA and AA, improved germination percentage was observed as against the control even under microgravity condition. The seedling dry weight, germination time and other germination parameters also showed similar improvements. Comparatively, the three growth stimulators showed no major variations in their ability to improve germination percentage under microgravitational impact. However, IAA showed more improvement on seedling vigor as against others, while GA showed more effect on the peak time and rate of germination. This research confirmed the possibilities of improving germinability of maize seeds under space exploration condition.

plant biology↗

bioRxiv2021

Influence of different anionic charges in lead compounds in the remediation of lead by Eleusine indica (Gaertn)

The study was carried out to investigate the remediative capacity of Eleusine indica in lead-polluted soil. Soil samples were collected near student hostel (hall 5) in the University of Benin. The soil samples were sun dried to constant weight and was pulverized with wooden roller and sieved with a hand sieve of 2 mm mesh size. The sieved soil was spiked with 0.625 g lead nitrate (PbNO3), lead sulphate (PbSO4), lead carbonate (PbCO3), lead acetetrahydrate (PbC2H6) and lead chloride (PbCl2) separately in three replicate using aqueous standard solutions. Tillers of Eleusine Indica were placed in the metal - polluted soil immediately and the experiment was allowed to stay for 15 weeks. The result showed that the uptake efficiency for Eleusineindica in both shoots and roots for lead nitrate was 0.016% and 0.8%, lead sulphate 0.016 % and 0.352 %, lead carbonate 0.064% and 0.496 %, lead acetetrahydrate 0.032 % and 0.688 %, and lead chloride 0.08 % and 0.72 % respectively, indicating that the plant might have sequestered the metal in the soil rather than accumulating it in the leaves. This was evident in the presentation of the metal sequestration factor of over 70 % irrespective of the nature of the metal. Microbial count of soil before and after contamination with lead nitrate was 1.9x104 and 0.4x104 cfu/g indicating a reduction. The study therefore revealed that Eleusine indica is a high efficient plant in sequestering lead in polluted soil.

plant biology↗

bioRxiv2021

In vitro assessment of elevated soil iron on germinability and germination characteristics of Sorghum bicolor (L.) Moench after chemo-priming

The commercial importance of Sorghum (Sorghum bicolor (L.) Moench) has attracted breeders to increase its seed yield using various breeding approach. Adverse soil factors however hampered progress made in crop development, especially micronutrient toxicity. Plant growth stimulators (PGS) have a significant role in enhancing growth parameters in Sorghum. In the present study, seeds were primed in 50, 150, and 250 ppm of each of gibberellic acid, indole acetic acid, and ascorbic acid respectively for 1 hr before sowing in Petri dishesmoistened with 10 ml of the iron-rich solution obtained as filtrate from a mix of distilled water and ferruginous soil (1:1 v/w). Results showed that although germination percentage in ferruginous medium was significantly reduced, there was enhancement in germination percentagewhen the seeds were primed in gibberellic acid (GA). Germinability in the iron-rich medium was 31.2 hrs; this was significantly reduced to 19.6 to 21.1hrs when these seeds were primed with growth stimulators.Although, shoot length was significantly reduced in plants exposed to ferruginous solutions, the root parameters were however enhanced. They were no significant changes in the total number of root branches regardless of ferrugenic status or use of growth stimulating agents. The utilization of growth stimulators as priming agents is called for to reduce stress impacts imposed by ferruginous soils during germination.

plant biology↗

bioRxiv2021

Implications of soil nitrogen enhancement on the yield performance of soybean (Glycine max) in cadmium-polluted soil

The growth, development and yield of important crop plants like soybean (Glycine max) are constantly under threat by continuous inputs of cadmium in the biosphere as a result of various industrial activities. This study investigated the level to which, addition of nitrogen fertilization can enhance plant survival, growth and yield development in a cadmium-polluted. Three accessions of Glycine max (TGm - 1, TGm - 2 and TGm - 3) were sown in a 12 mg/kg-cadmium polluted, which was thereafter amended with urea (FU), ammonia (FA), and ammonium nitrate (FN) singly and in combinations of equal proportions. A non-fertilized Cd-polluted soil and a general control constituted the negative and positive controls. Results showed that although N application did not enhance yield dispositions of soybean in Cd-polluted soil, significant impact on vegetative development was noteworthy. Compared to yield of control plants, cadmium pollution imposed a 26.1 % reduction in per plant yield in TGm-1, compared 1.71 % in TGm-3. Generally, addition of nitrogenous fertilizer further suppressed crop yield by as much as 80 % in plants sown in cadmium-polluted soil. However, application of ammonia fertilizer to TGm-2 improved its yield performances in the cadmium-polluted soil.

plant biology↗

bioRxiv2020

Screening bacterial isolates for phosphate Solubilizing capability in a ferruginous ultisol in Benin City, Edo State Nigeria.

Phosphorus is a major growth-limiting nutrient which plays important biochemical role in photosynthesis, respiration and several other processes in the living plant. It is widely distributed in minerals as phosphates. It reacts easily with Fe3+ in ferruginous ultisols and therefore not bioavailable for plant usage. Many bacteria have the ability to solubilize phosphate minerals and make it bioavailable to plants. Thus this research investigates the culturable bacterial composition of ferruginous ultisol, comparative to control soils as well as the phosphate solubilizing capabilities of the isolates for future use in soil improvements. Six soil samples of different ferruginous levels and a control were assayed for physicochemical parameters prior to the experiment. Culturable bacteria as well as the phosphate solubilizing bacteria (PSB) were assayed in Pikovskayas medium at 27{degrees}C with 7.5 pH for 7days. Six distinct isolates were observed which proved to be Proteus spp., Pseudomonas spp., Klebsiella spp., Salmonella spp., Bacillus spp. and Serratia spp. based on biochemical and morphological characteristics. Of these six isolates, three isolates (EMBF2-Klebsiella spp, BCAF1- Proteus spp and BCAC2- Bacillus spp) were identify to solubilize phosphate by releasing a considerable amount of phosphate (12.01-21.23 ppm) and lowering the pH of the media. The three isolates showed tolerance to acidic and alkaline media and also showed plant growth promoting capabilities by releasing IAA and siderophores. The result revealed that the three isolates had potential to chelate the ion bond in Fe3+ in ferruginous ultisol by releasing low molecular weight organic acid, making phosphate to be bioavailable for plant usage. This will serve as biofertilizer in improving yield of crops in ferruginous ultisol and improve soil fertility.

microbiology↗