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Snake gourd botanically known as Trichosantes cucumerina locally called tomato agwo. T.cucumerina is considered a neglected and underutilised crop. Detailed characterisation of this crop is not known in Nigeria and other African countries. This study was done to access fourteen accessions of T. cucumerina from Nigeria using Internal Transcribed Spacer (ITS). The fourteen accessions from different ecological regions were sequenced with ITS1 and ITS4 by direct PCR products. The results obtained were at minimum (570) and maximum (580) base pairs. The query coverage ranging from 99.4 % to 100 % affirms positive amplification and sequencing of snake gourd ecotypes using ITS1 and ITS4. The phylogenetic tree of the characterization group T. cucumerina was divided into three clusters. The phylogenetic tree of the characterization grouped T.cucumerina into three clusters. The genetic distances between the samples revealed that Ukwa, NACGRAB, Ikwuano, Oshogbo, Ikom, and Rumibekwe were closely related. Benin, Nasarawa, Oye-Ekiti, Ilorin, and NHST-0583 shared no genetic relationship as revealed by their genetic distances. The genetic distance ranged from 0.217 - 2.010. T. cucumerina landraces studied in Nigeria thirteen were T. cucumerina var anguina. The NHST -0583 from the seed center was the only T.cucumerina var cucumerina in Nigeria. This was blasted on the National Center for Biotechnology Information (NCBI) website. The sequenced blast in the NCBI data website was to be similar to accession numbers GU059528.1 and GQ240883.1 respectively. These have given scientists critical knowledge regarding T. cucumerina molecular breeding in Nigeria [ABSTRACT FROM AUTHOR]

Legumes are important components of sustainable agricultural production, food, nutrition and income systems of developing countries. In spite of their importance, legume crop production is challenged by a number of biotic (diseases and pests) and abiotic stresses (heat, frost, drought and salinity), edaphic factors (associated with soil nutrient deficits) and policy issues (where less emphasis is put on legumes compared to priority starchy staples). Significant research and development work have been done in the past decade on important grain legumes through collaborative bilateral and multilateral projects as well as the CGIAR Research Program on Grain Legumes (CRP‐GL). Through these initiatives, genomic resources and genomic tools such as draft genome sequence, resequencing data, large‐scale genomewide markers, dense genetic maps, quantitative trait loci (QTLs) and diagnostic markers have been developed for further use in multiple genetic and breeding applications. Also, these mega‐initiatives facilitated release of a number of new varieties and also dissemination of on‐the‐shelf varieties to the farmers. More efforts are needed to enhance genetic gains by reducing the time required in cultivar development through integration of genomics‐assisted breeding approaches and rapid generation advancement. [ABSTRACT FROM AUTHOR]

Cercospora leaf spot (CLS) caused by Pseudocercospora cruenta (Sacc.) is an important disease affecting cowpea production in Nigeria. Understanding the genetic nature of CLS is an important step in developing an effective breeding strategy. This study investigated the inheritance of CLS disease in cowpea under natural epiphytotic field condition involving two CLS resistant parents (IT99K-573-1-1, IT99K216-24) and a CLS susceptible parent (UAM09-1055-6). The parental lines, F1, BC1P1, BC1P2, F2 and F3 generations were used to study the genetic nature and to detect SSR markers closely linked with the CLS resistance gene(s) using bulked segregant analysis (BSA). The result showed that F1 populations involving UAM09-1055-6 × IT99K-573-1-1 and UAM09-1055-6 × IT99K-216-24 were resistant to CLS in the 2 crosses suggesting the presence of gene dominance in the control of the disease. The observed segregating ratio of F2 populations fits the Mendalian ratio 3:1. The plants reaction to the disease in the backcross progeny test involving the resistant parent were all uniformly resistant, whereas those involving the susceptible parent segregated into ratio 1:1. The F3 generations, which segregated into ratio 1:2:1 further confirmed that resistance was controlled by a single dominant gene in the crosses studied. Heritability estimates varied from 81 to 97%. BSA showed that SSR marker code named RB24 of lima bean and validated on F2 population discriminated between resistance and susceptibility to CLS. Hence RB24 could be a useful marker for marker-assisted selection in CLS resistance breeding in cowpea. [ABSTRACT FROM AUTHOR]