Controlled transmission of African cassava mosaic virus (ACMV) by Bemisia tabaci from cassava (Manihot esculenta Crantz) to seedlings of physic nut (Jatropha curcas L.)

Jatropha curcas, a plant with great biodiesel potential is also used to reduce the population of whiteflies, Bemisia tabaci on cassava fields when planted as a hedge. We therefore, investigated the transmission of African cassava mosaic virus (ACMV) by the whitefly vector from cassava to seedlings of 10 accessions of J. curcas as part of a wider investigation on the possible role of J. curcas as an alternative host of ACMV. Transmission tests were conducted in insect-proof cages using adult B. tabaci collected from ACMV-infected cassava in the field, at a rate of three adult whiteflies per J. curcas seedling and a transmission feeding period of four days. Twenty one (21) days after the infestation, leaf samples from individual plants of the 10 J. curcas accessions were tested for the presence of ACMV by the polymerase chain reaction (PCR) and the double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA), using the monoclonal antibodies SCRI 33. DAS-ELISA detected ACMV in five out of the ten J. curcas accessions while PCR detected it in eight of the 10 accessions. Furthermore, 18 out of the 35 Nicotiana benthamiana indicator plants mechanically inoculated with sap from symptomatic J. curcas seedlings produced symptoms typical of ACMV infection. This indicates that J. curcas is a likely host of ACMV and it may in turn, be able to infect cassava, and presumably other ACMV-susceptible hosts, in the presence of the vector.Keywords: Jatropha curcas accessions, controlled transmission, mechanical inoculation, enzyme-linked immunosorbent assay, African cassava mosaic virus (ACMV)-susceptible hosts.African Journal of Biotechnology Vol. 12(28), pp. 4465-447

Agronomic Evaluation of Eight Genotypes of Hot Pepper (Capsicum Spp L.) in a Coastal Savanna Zone of Ghana

Local landrace varieties of pepper (Capsicum sp) often fail to meet the expectations of farmers with respect to fruit yield, while exotic breeds are unadapted to local conditions, with detrimental effects on local pepper production. The aim of the study was to assess the agronomic performance of eight (8) pepper genotypes, comprising 6 exotic and 2 local genotypes, under rain-fed conditions to identify those suitable for cultivation locally. The experiment was conducted between April and October 2011 at the research farm of the Biotechnology and Nuclear Agriculture Research Institute of the Ghana Atomic Energy Commission. The Randomized Complete Block Design (RCBD), with three replicates was used. Weed control was carried out manually with the aid of a hoe and a cutlass at 4 and 10 weeks after planting (WAP).  One application of 15-15-15 NPK fertilizer was made at 2 WAP, using a rate of 200 kg ha-1. No pesticides or fungicides were applied. Parameters measured include number of days to 50% flowering, height at first branching, total plant height at maturity, canopy spread at maturity and total yield. Results indicate that exotic hybrid varieties matured earlier than the local genotypes. They also performed better in terms of fruit weight, fruit length and fruit yield. However, the two local landrace varieties, Anloga and Legon 18, produced the highest number of undamaged fruits. Keywords: Capsicum sp, genotypes, exotic pepper, landrace, yield, plant height, fruit weigh

In vitro assessment of crude oil degradation by Acinetobacter junii and Alcanivorax xenomutans isolated from the coast of Ghana

This study was aimed at using in vitro microcosm experiments to assess crude oil degradation efficiency of Acinetobacter junii and Alcanivorax xenomutans isolated along Ghana's coast. Uncontaminated seawater from selected locations along the coast was used to isolate bacterial species by employing enrichment culture procedures with crude oil as the only carbon source. The isolates were identified by means of the extended direct colony transfer method of the Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectroscopy (MALDI-TOF MS), as Acinetobacter junii, and Alcanivorax xenomutans. Remediation tests showed that Acinetobacter junii yielded degradation efficiencies of 27.59 %, 41.38 % and 57.47 %. Whereas efficiencies of 21.14 %, 32.18 % and 43.68 % were recorded by Alcanivorax xenomutans representing 15, 30 and 45 days respectively. Consortia of Acinetobacter junii, and Alcanivorax xenomutans also yielded 32.18 %, 48.28 % and 62.07 % for the selected days respectively. Phylogenetic characterization using ClustalW and BLAST of sequences generated from the Oxford Nanopore Sequencing technique, showed that the Ghanaian isolates clustered with Alcanivorax xenomutans and Acinetobacter junii species respectively. An analysis of the sequenced data for the 1394-bp portion of the 16S rRNA gene of the isolates revealed >99 % sequence identity with the isolates present on the GenBank database. The isolates of closest identity were Alcanivorax xenomutans and Acinetobacter junii with accession numbers, NR_133958.1 and KJ147060.1 respectively. Acinetobacter junii and Alcanivorax xenomutans isolated from Ghana's coast under pristine seawater conditions have therefore demonstrated their capacity to be used for the remediation of crude oil spills