Impact of natural weed infestation on the performance of selected sugarcane varieties in the Southern Guinea Savanna of Nigeria

Experiments were conducted to evaluate the performance of some  sugarcane varieties against natural weed infestation. The trials were laid out in a randomized complete block design with split-plot arrangement andthree replications. The sugarcane varieties were the main plots while the sub-plots consisted of weeding regimes. Recommended cultural and agronomic practices were followed to raise the crops. Data were collected on weed density, weed biomass, sugarcane tiller count and cane yield. Our results revealed that Rottboellia cochinchinensis (Lour.) W.D.Clayton, Panicum maximum Jacq, Imperata cylindrica L., Panicum repens L., Cynodon dactylon L. and Cyperus rotundus L. were the major weed problems of sugarcane in Ilorin. The monthly hoe weeded treatment had significantly higher tiller count which translated to higher cane yield (22.61 to 72.54 t/ha) than other weed control treatments. The reduction in cane yield was between 80.51 and 97.55% depending on duration of weed infestation. Association of weed parameters with cane yield was negative and significant showed that a decrease in weed infestations will result in simultaneous increase in sugarcane yield. Therefore, in selecting  sugarcane variety(s) for breeding programmes, emphasis should be placed on sugarcane growth parameters that negatively and significantly correlated with weed infestation. Key Words: Weeds, sugarcane, plant crop, ratoon, cane yield, tiller coun

Evaluation of Cocoyam-Soybean Flour Blends and Sensory Properties of the Amala Dumpling

Amala, a staple food among the Yoruba people of South West Nigeria, is mostly produced from yam. Since yam is known to be mostly carbohydrate and soybean is a legume with an appreciable quantity of protein, efforts have been made to prepare amala from the blends of cocoyam and soybean flours. The protein content of the flour blends ranged from 3.73% to 13.81%. In general, there was increase in the concentration of protein with increasing level of soy flour substitution. Unlike protein, the crude fibre content of the flour blends decreased with increasing supplementation of soy flour. Increase in oil content of the flour samples, with increasing addition of soy flour, predisposes the samples to shorter shell life and off flavor because of liability to rancidity. The lowest bulk density of 0.78 g/cm3 was recorded for sample A (100% cocoyam flour) and hence none of the flour blends could be considered as a complimentary infant substitute. In general, supplementation of cocoyam flour with soy flour enhanced the concentrations of protein, ash and dietary fibre. Therefore, it is hoped that consumption of cocoyam amala supplemented with soy flour, a cheap source of plant protein, will not only create dietary diversity, it will make more protein available for the consumers and thus help in alleviating the problem of protein energy malnutrition in developing regions of the world

Influence of Tillage Systems on Diversity and Abundance of Insect and Nematode Pests of Maize in Malete, Kwara State, Nigeria

Pests are major biotic factors causing up to 45% yield reduction in maize production in sub-Saharan Africa. To develop improved methods for maize management, the species and abundance of insects and nematodes associated with ten quality protein maize varieties (QPMVs) were evaluated with two commonly used tillage practices, ‘plough only plots (POP)’ and ‘plough and harrow plots (PAHP)’. The experiment was carried out using QPMVs at the Teaching and Research Farm of the Kwara State University, Malete, Nigeria, and arranged in a randomized complete block design with 11 treatments replicated 3 times, including local check “pambo”. A total of 833.1±4.0 and 799.3±3.4 arthropods specimens were collected from POP and PAHP, respectively, comprising 8 orders and 18 families. Ootheca mutabilis was the most abundant species with 5.47% (POP) and 5.68% (PAHP) and the least abundant was Rhopalosiphum maidis 1.82% (POP) and 1.80% (PAHP). As indicated by Shannon Wiener (3.46±0.023) and Simpson indices (0.97±0.0008) there are even distribution in the tillage practices. Three genera of plant parasitic nematodes (PPNs) were identified, Meloidogyne spp. (POP (78.33±19.65), PAHP (1.33±0.33), Pratylenchus spp. (POP (41.67±9.26), PAHP (5.00±2.31), and Helicotylenchus spp. (POP (58.33±38.35), PAHP (23.33±14.50). The use of PAHP tillage practices is effective in reducing insects and nematodes associated with maize in Nigeria and therefore recommended for the management of both pests in maize production

Ultrastructural and functional fate of recycled vesicles in hippocampal synapses

Efficient recycling of synaptic vesicles is thought to be critical for sustained information transfer at central terminals. However, the specific contribution that retrieved vesicles make to future transmission events remains unclear. Here we exploit fluorescence and time-stamped electron microscopy to track the functional and positional fate of vesicles endocytosed after readily releasable pool (RRP) stimulation in rat hippocampal synapses. We show that most vesicles are recovered near the active zone but subsequently take up random positions in the cluster, without preferential bias for future use. These vesicles non-selectively queue, advancing towards the release site with further stimulation in an actin-dependent manner. Nonetheless, the small subset of vesicles retrieved recently in the stimulus train persist nearer the active zone and exhibit more privileged use in the next RRP. Our findings reveal heterogeneity in vesicle fate based on nanoscale position and timing rules, providing new insights into the origins of future pool constitution

QTL analysis for resistance to foliar damage caused by Thrips tabaci and Frankliniella schultzei (Thysanoptera: Thripidae) feeding in cowpea [Vigna unguiculata (L.) Walp.]

Three quantitative trait loci (QTL) for resistance to Thrips tabaci and Frankliniella schultzei were identified using a cowpea recombinant inbred population of 127 F2:8 lines. An amplified fragment length polymorphism (AFLP) genetic linkage map and foliar feeding damage ratings were used to identify genomic regions contributing toward resistance to thrips damage. Based on Pearson correlation analysis, damage ratings were highly correlated (r ≥ 0.7463) across seven field experiments conducted in 2006, 2007, and 2008. Using the Kruskall–Wallis and Multiple-QTL model mapping packages of MapQTL 4.0 software, three QTL, Thr-1, Thr-2, and Thr-3, were identified on linkage groups 5 and 7 accounting for between 9.1 and 32.1% of the phenotypic variance. AFLP markers ACC-CAT7, ACG-CTC5, and AGG-CAT1 co-located with QTL peaks for Thr-1, Thr-2, and Thr-3, respectively. Results of this study will provide a resource for molecular marker development and the genetic characterization of foliar thrips resistance in cowpea

Genotoxicity assessment of a pharmaceutical effluent using four bioassays

Pharmaceutical industries are among the major contributors to industrial waste. Their effluents when wrongly handled and disposed of endanger both human and environmental health. In this study, we investigated the potential genotoxicity of a pharmaceutical effluent, by using the Allium cepa, mouse- sperm morphology, bone marrow chromosome aberration (CA) and micronucleus (MN) assays. Some of the physico-chemical properties of the effluent were also determined. The A. cepa and the animal assays were respectively carried out at concentrations of 0.5, 1, 2.5, 5 and 10%; and 1, 5, 10, 25 and 50% of the effluent. There was a statistically different (p < 0.05), concentration-dependent inhibition of onion root growth and mitotic index, and induction of chromosomal aberrations in the onion and mouse CA test. Assessment of sperm shape showed that the fraction of the sperm that was abnormal in shape was significantly (p < 0.05) greater than the negative control value. MN analysis showed a dose-dependent induction of micronucleated polychromatic erythrocytes across the treatment groups. These observations were provoked by the toxic and genotoxic constituents present in test samples. The tested pharmaceutical effluent is a potentially genotoxic agent and germ cell mutagen, and may induce adverse health effects in exposed individuals

Reduced Expression of the Vesicular Acetylcholine Transporter and Neurotransmitter Content Affects Synaptic Vesicle Distribution and Shape in Mouse Neuromuscular Junction

In vertebrates, nerve muscle communication is mediated by the release of the neurotransmitter acetylcholine packed inside synaptic vesicles by a specific vesicular acetylcholine transporter (VAChT). Here we used a mouse model (VAChT KDHOM) with 70% reduction in the expression of VAChT to investigate the morphological and functional consequences of a decreased acetylcholine uptake and release in neuromuscular synapses. Upon hypertonic stimulation, VAChT KDHOM mice presented a reduction in the amplitude and frequency of miniature endplate potentials, FM 1-43 staining intensity, total number of synaptic vesicles and altered distribution of vesicles within the synaptic terminal. In contrast, under electrical stimulation or no stimulation, VAChT KDHOM neuromuscular junctions did not differ from WT on total number of vesicles but showed altered distribution. Additionally, motor nerve terminals in VAChT KDHOM exhibited small and flattened synaptic vesicles similar to that observed in WT mice treated with vesamicol that blocks acetylcholine uptake. Based on these results, we propose that decreased VAChT levels affect synaptic vesicle biogenesis and distribution whereas a lower ACh content affects vesicles shape

Globular cluster systems and galaxy formation

Globular clusters are compact, gravitationally bound systems of up to a million stars. The GCs in the Milky Way contain some of the oldest stars known, and provide important clues to the early formation and continuing evolution of our Galaxy. More generally, GCs are associated with galaxies of all types and masses, from low-mass dwarf galaxies to the most massive early-type galaxies which lie in the centres of massive galaxy clusters. GC systems show several properties which connect tightly with properties of their host galaxies. For example, the total mass of GCs in a system scales linearly with the dark matter halo mass of its host galaxy. Numerical simulations are at the point of being able to resolve globular cluster formation within a cosmological framework. Therefore, GCs link a range of scales, from the physics of star formation in turbulent gas clouds, to the large-scale properties of galaxies and their dark matter. In this Chapter we review some of the basic observational approaches for GC systems, some of their key observational properties, and describe how GCs provide important clues to the formation of their parent galaxies.Comment: 32 pages, 6 figures. Accepted for publication in the book "Reviews in Frontiers of Modern Astrophysics: From Space Debris to Cosmology" (eds Kabath, Jones and Skarka; publisher Springer Nature) funded by the European Union Erasmus+ Strategic Partnership grant "Per Aspera Ad Astra Simul" 2017-1-CZ01-KA203-03556