No abstract

Gnetum africanum is a twisted woody climbing wild plant i.e.liana found growing naturally in dense equatorial rainforest but currently domesticated in tropical areas of the world. There has been taxonomic confusion in classifying this liana due to its observable diverse morphological characters. Indeed, morphological characterization alone has not offered the needed solution. However, there is dearth of information on the molecular characterization of Gnetum africanum. Morphological and molecular descriptors, could help offers the needed phenotypic and genotypic characterization of this plant much better. This study is aimed at characterizing Gnetum africanum land races to identify species that could be used for the development of high yielding hybrids. Three different land races or accessions of Gnetum africanum was collected from different locations in Nigeria. High quality genomic DNA was isolated from the different samples; it was checked for purity and quantified as appropriate. The DNA samples were subjected to PCR amplification and DNA barcoding studies (chloroplast large subunit of ribulose -1, 5-bisphophate carboxylase rbcL gene). The amplicons were gel eluted, sequenced and checked for homology by using Basic local alignment search tool -BLAST. Identification was obtained from the top similar outcomes of the samples. For Ekim Fig. 1b sample, the forward blast showed 95% similarity with Basella alba voucherID: NC041293.1 and the reverse had 88% similarity with Talinum fruticosum cultivar ID: MK598685.1. For Etinan Fig. 1a sample, the forward blast had 86% similarity with Rhabdothamnussolandri voucher ID: JQ933464.1 and for reverse, there was no similarity founded.

Two animal manure sources (swine and sheep / goat manures) each at 5 Mt·ha−1, were applied in mono- and intercropped maize (Zea mays L.) and groundnut (Arachis hypogea L.). A general control (no manure treatment of the component crops was established) for productivity assessment. The trial, conducted at the Federal College of Agriculture, Ishiagu (04º 30′ N, 06º 45′ E, 150 m above sea level), in the derived savannah plains, Ishiagu, Nigeria in 2012 and 2013 mid-cropping seasons used a randomised complete block design with three replications. It assessed the agronomic performance, cropping system (CS) and plant nutrient (PN) productivity of maize-groundnut in mono-and intercrop as influenced by two animal manure sources. The two-year combined analysis indicated that animal manure sources significantly (P < 0.05) increased growth and yield components of the crop species in the systems. Swine manure application gave the significantly (P < 0.05) highest maize grain yield in both mono- and intercropped strategies in contrast to sheep / goat manure that had the highest grain yield in both cropping strategies in groundnut. The biological and economic productivity indices of the cropping system (CS) and plant nutrient (PN) indicated that the application of sheep / goat manure in the maize / groundnut mixture exhibited greater intercrop advantage whose total CS and PN land equivalent ratios (LERs) were higher by 4.79% and 13.57%, respectively, relative to swine manure application. Therefore, the application of animal manure demands encouragement in maize-groundnut intercrop, especially sheep / goat manure as it enhances crop yield, food security and protein intake of people living in Sub-Saharan Africa practicing different strokes of farming system technology. The results of this study showed that intercropping system exhibited positive growth, yield, biological and economic advantages over monocropping of the component species. The study further indicated that intercropped maize / groundnut that received sheep / goat manure exhibited the highest cropping system and plant nutrient yield advantage and agronomic efficiency compared to swine manure alone under the same environment.