Nigeria's restricted data on trait associations in cowpea genotypes has required setting up a study in this region to better understand the interactions between cowpea characteristics. The objectives of this study were therefore to assess the level of genetic variability and inter-character association among accessions of cowpea. Eight selected accessions from IITA were evaluated in the field in a Randomized Completely Block Design (RCBD) with three replications between September and December, 2018. Each replicate comprised eight accessions in plots of 5 m x 1 m dimension each; accessions were sown at 30 cm intra and 50 cm inter row spacing with 1 m separation between the accessions. Sixteen (16) quantitative traits were evaluated using five plants per accession per replicate. Significant differences were observed among accessions for most studied traits. Phenotypic variance was higher than genotypic variance for traits evaluated. High broad sense heritability and genetic advance as percent of mean were observed for emergence percentage, seeds per pod, seed weight; the seeds per plant had positive correlation with pod per plant and seed yield, indicating that selection for these will result in increase in yield. PCs 1 and 2 (with eigen value >1) accounted for more than 75.63% of the total variations among accessions. Different patterns of associations and genotype (accession) by trait interactions were observed. The genotype x trait bi-plots consistently indicated that seed yield had positive associations with most of the traits; especially peduncles per plant, seeds per plant, terminal leaflet length and terminal leaflet width. Analysis (PCA).Knowledge on the type and extent variation of the existing plant material and the interaction between the different characters are necessary for improving the yield [25]. Therefore knowledge of genetic variation, inheritance and genetic advance is needed for a breeder to select the best genotypes of cowpea for improvement. The assessment of genetic parameters reveals how relative the various types of genetic effects influence a difference in a plant's overall I. Adedeji et al.,; South Asian Res J Bio Appl Biosci; Vol-2, Iss-1 (Jan-Feb, 2020): 7-15 © South Asian Research Publication, Bangladesh Journal Homepage: www.sarpublication.com/sarjbab 8 PCV = (√Vp/X) 100…..eq. 3 GCV = (√Vg/X) 100…...eq. 4here V V and X are phenotypic variance genotypic variance and grand ean respective y for traits under consideration, and were classified according to [22].as follows: 0 -10% = low; 10 -20% = moderate; 20% = high. EM=Emergence percentage, PH= Plant height, NL= Number of leaves, NMB= Number of main branches, TLL= Terminal leaflet length, TLW= Terminal leaflet width, NODFF= Number of days to first flowering, PEDL=Peduncle length, PEDPL= Peduncle per plant, PDPE= Pod per peduncle, PDL= Pod length, SPPD= Seed per pod, SDPL=Seed per plant, PDPL= Pod per plant SW= Seed weight, SYD=Seed yield.

Aim:The research focused on the performance of six exotic rice genotypes from Malaysian Agricultural Research and Development Institute (MARDI) in a Nigerian agro-ecology. Study Design: The varieties were evaluated in randomized complete block design replicated three times.

No abstract

This study was conducted over a two-year period (two seasons) to assess the potentials of mini tuber production, through vine cutting propagation on four local varieties of yam (Agbagba, Danisa, Shangari and Alata). Three propagation media used were sandy loamy soil, sandy loamy soil with carbonized rice husk (1:7) and sandy loamy soil with carbonized sawdust (1:7). The set up was a 4 by 3 factorial experiment laid out in a Completely Randomized Design (CRD) with three replicates consisting of 288 excised vines with 24 vines per variety per treatment per replicate. The data obtained (percentage survival of vines, number of rooted vines, vines with shoots, numbers of roots/vine, vines with tubers, and number of tubers/vine and fresh weight of tuber/vine) were subjected to statistical analysis and their means compared. Analysis of variance (ANOVA) revealed high significant differences (P ≤ 0.01) in percentage survival, number of rooted vines, number of roots/vine, vines with shoots, vines with tubers, number of tubers and fresh weight of tubers among treatments, varieties, and treatment by varieties in the two seasons of the study. Percentage survival of vines and number of vines with tubers/pot were generally higher in all Dioscorea rotundata (agbagba, danisa and shangari) than in Dioscorea alata in both seasons while rooting of vines and fresh weight of tubers/vine were better in Dioscorea alata. Also, sandy loamy soil proved to be the best medium of propagation followed by sandy loamy soil with carbonized rice husk while sandy loamy soil with carbonized saw dust was the least.

High yielding rain-fed lowland rice cultivars are sensitive to complete submergence stress of more than four days. In Nigeria, rice farms on about 3.6 million ha of rain-fed lowland areas are adversely affected by submergence stress. Consequently, farmers in the major rice producing states of the country lose their entire crop to flooding each year. The identification of a major quantitative traits locus (QTL) on chromosome 9, designated as sub1, has provided the opportunity to apply marker assisted selection to develop submergence tolerant varieties. This study was undertaken to introgress sub 1 into the genetic background of Nigerian lowland rice mega variety (WITA 4) and assess the ability of WITA 4 with sub 1 to withstand submergence stress. Swarna Sub1, one of the FR13A-derived submergence tolerant varieties developed by IRRI, was crossed to WITA 4, a submergence intolerant Nigerian mega variety to produce F1 hybrid. The derived BC1F2 progenies were genotyped and BC1F3 phenotyped. The results of genotyping, using two markers, namely ART5 and SC3, revealed that 18 BC1F3 plants were found carrying Swarna Sub 1 allele of ART5 while 41 BC1F3 carried WITA 4 allele of ART5. Twenty progenies were found carrying Swarna Sub 1 allele of SC3 while 37 plants carried WITA 4 allele. Two plants carried both alleles (H). Seventeen plants were observed to carry Swarna Sub 1 alleles at both markers loci while a total of 36 progenies were observed to carry WITA 4 alleles at both markers loci. The results of the phenotypic screening showed that 12 plants recorded percentage survival above 60%. The two markers showed high selection accuracies, and selection based on the markers could satisfactorily meet the needs of breeding for submergence.