No abstract

The objective of the research was to test the effect of sowing dates, intra-row spacing and biopesticides on the larval population dynamics of M. vitrata in Samaru, Nigeria. The experiment was laid out with biopesticides (B0; control, B1; Neem seeds kernel extract (NKE), B2; Maruca vitrata Multinucleopolyhedrosis virus (MaviMNPV) suspension and B3; Cyper diforce (30 g cypermethrin + 250 g dimethoate). The result at 10 WAS showed that varying sowing dates to SD3 significantly (P=.01) reduced mean population of M. vitrata larva in sampled flowers in all the years and the combine. MaviMNPV was effective in reducing pod borer populations (7.22, 6.11 and 6.67) better than NKE (10.19, 5.74 and 7.96) and Cyper diforce (7.41, 8.89 and 8.15). The control significantly recorded the highest mean (11.67, 12.59 and 12.13) population in all the years and the combined. Similarly, varying sowing dates to SD3 significantly reduced mean population (5.56, 5.00 and 5.28) of M. vitrata in cowpea pods sampled 10 WAS better than SD1 and SD2. Statistically similar effect of biopesticides was observed on mean population of M. vitrata, however, the control recorded the highest mean (22.59 and 13.89) in 2015 cropping season and the combined. High cowpea grain yield was obtained in SD2 (337.85, 689.10 and 800.66 kg ha -1 ) even though statistically similar with SD3 (244.89, 618.10 and 639.68 kg ha -1 ). Cyper diforce treated plots gave the highest yield of 394.56, 887.69 and 976.51 kg ha -1 during 2015 and 2016 cropping seasons and combine but was statistically at far (P=.01) with NKE and MaviMNPV. The interaction of SD2 and Cyper diforce gave the highest grain yield. The effect of sowing at SD2 and insecticide spray will give a better control of M. vitrata for an increased yield of cowpea in the study area.

The present review focuses on some major researches dealing with controlling Cowpea seed bruchid (CSB) due to Callosobruchus maculatus (Fab.) [Coleoptera: Bruchidae] by using some plant products. The objective of this review is to look in to the successes of the use of plant materials in the management of CSB especially in the tropics where bulk of the crop is cultivated and consumed. The review of available literature showed that, plants such as Neem, Azadirachta indica A. Juss; Garlic, Allium sativum (L.); West African pepper, Piper guineense Schumach; drum stick, Moringa oleifera Lam; African Basil, Ocimum gratissimum (L.); Moss plant; Barbula indica and Clausena anisata (Willd.) Hook has been used in CSB control. Available literatures showed that garlic, chilies and peppermint applied at the rate of 0.035-0.55g significantly (p≤0.05) reduced oviposition, respectively compared to the control. Similarly, powdered flowers of M. oleifera applied at the rate of 0.5 g per 30 g of seeds caused mortality of CSB better than the control 8 hours after infestation. The use of C. anisata and Permethrin showed percentage mortality of cowpea bruchids was high using Permethrin but was not significantly (p≥0.05) better than Clausena leaf powder. Groundnut oil applied at ˂ 4mls kg -1 does not affect germination process of cowpea stored for up to 12 weeks. However, increasing rate of application decreases germination. The review clearly indicated that plant products have potentials of controlling CSB in stored cowpea as they are safe and free from residue. They are hereby encouraged.

To determine the features of the microstructure of choreoretinal complex in rats with diabetes induced by streptozotocin in the presence of axial myopia. Material and Methods: Fifty-five Wistar rats (110 eyes; age, 2 weeks to 14 weeks) were used in experiments. Four groups were formed: group 1 (axial myopia only); group 2 (diabetes only); group 3 (both myopia and diabetes); and group 4 (controls; intact animals). High form-deprivation myopia was produced in two-week animals by surgically fusing the eyelids of both eyes and these animals were maintained under conditions of reduced illumination for two weeks to induce a more intense myopization of the globe. Eyelid sutures were removed on completion of these two weeks. Two weeks thereafter, type 2 diabetes mellitus was induced in rats with induced axial myopia and intact rats. A 50 mg/kg intraperitoneal streptozotocin injection for 5 days was used for this purpose. Elongated axial length and increased anterior chamber depth as measured by in vivo ultrasound were an objective criterion of the development of myopia in experimental animals. A glucose level of ≥ 4.5 mmol/L was a criterion of the development of diabetes. Two months after inducing diabetes, 14-week rats were sacrificed, and their eye tissue samples were processed by a routine method and assessed by electron microscopy. Ultrastructure of the choroid, RPE, and retinal photoreceptor cells were examined. Ultra-thin sections were cut, stained with lead citrate according to the procedure described by Reynolds, and observed with a PEM-100-01 Transmission Electron Microscope. Results: Our ultrastructural study found that myopization of the rat globe with elongation of the axial length somewhat reduced the severity of some ultrastructural changes in the choreoretinal complex in induced type 2 diabetes due to reduced choroidal swelling and dominance of compensatory processes with increased energy producing, protein synthesis and other functions in the endothelial vessels and choriocapillaries as well as RPE cells. Out findings seem to corroborate the concept that myopized eyes have capacity to somewhat buffer the development of severe diabetic retinopathy, likely due to some compensatory-andrestorative processes.

A combination of intra-row spacings, sowing dates, and pesticides on cowpea damage and control caused by M. vitrata was carried out towards developing an integrated pest management of M. vitrata on cowpea. The experiment was laid out in split-split plot design. Intra-row spacing and sowing dates were respectively allocated to the main and sub-plot while pesticides were allocated to the sub-sub-plot. The treatments were randomized and replicated three times. Data collected were subjected to the analysis of variance and means were separated using LSD at 5%. The result showed that varying intra-row spacings did not have any significant effect (P>0.05) on cowpea flower damage by M. vitrata at 10 WAS in all the years and the combine except in 2016. Close spacing was observed to record the least flower damage. Early sowing was observed to significantly (P<0.05) recorded the highest percentage flower damage in all the years and the combine (22.95, 22.78 and 22.85). Pesticide treated plots (13.06, 13.06 and 11.67) significantly (P<0.05) recorded the least percentage flower damage compared with the control plots (26.30). The effect of pesticides was statistically similar, however plots treated with Cyper diforce during recorded the least percentage flower damage. There was no significant difference on the effect of varying intrarow spacing on percentage cowpea pod damaged by M. vitrata 10 WAS. However, delay in sowing to SD3 significantly recorded least percentage pod damage (4.89, 14.03 and 2.94) than early sowing SD1 (24.47, 30.14 and 12.74) which recorded the highest. The effect of pesticides showed that plots treated with MaviMNPV significantly (P<0.05) recorded the least percentage damage (6.69) compared with the control (13.08). However, treatments effects were statistically similar. The effect of varying sowing dates showed that sowing cowpea at SD3 significantly (P<0.05) reduce dried cowpea pod damage at harvest (5.55% and 6.81%) than early sowing SD1 (12.85% and 10.61%) during 2016 and the combine respectively. It is therefore recommended that varying sowing date and use of Cyper diforce reduce cowpea damage in the study area and is hereby recommended.