Accessions Of Groundnut Research Articles

Morphometric diversity of some Nigerian accessions of Bambara groundnut (Vigna subterranea)

AbstractThis study evaluated the morphological diversity of some Nigerian accessions of Bambara groundnut. Field experiments were conducted in Nigeria in two locations and the phenotypic variation of Bambara groundnut accessions evaluated in 3 years (2017–2020) using a randomized complete block design. Twenty-eight quantitative and 10 qualitative traits were observed. Twenty-three out of the 28 quantitative morphological traits showed significant differences. TVSu-589 (28.85) and TVSu-670 (28.57) had the highest plant height; TVSu-572 (121.52), TVSu-271 (113.10) and TVSu-336 (104.15) had the highest 100-seed weight. Genetic variations were also observed in seed colour, terminal leaflet shape, petiole colour and eye pattern. Principal component analysis showed PC1 constituting 23.36% and PC2 constituting 15.76% of the total variation, while the first eight principal components with eigenvalues ≥1 revealed 77.28% of the total variation. Cluster analysis grouped the accessions into four groups. Based on yield data in this study, accessions TVSu-594, TVSu-350, TVSu-336, TVSu-1242, TVSu-129, TVSu-14, TVSu-179, TVSu-2100, TVSu-261 and TVSu-589 were the best for yield and are recommended for further evaluation to improve yield. This study showed that a wide range of diversity exists in Bambara groundnut of Nigerian origin that could be useful for further utilization of genetic resources and improvement.

Screening and genotyping of groundnut (Arachis hypogea L.) inbred lines and landraces in the North Central Nigeria

The study evaluated 33 accessions of groundnut in the field, consisting of 23 landraces from Nasarawa communities in Nigeria and 10 inbred lines. Assessment entailed the determination of plant survivorship, yield related parameters and pathological indices while genetic diversity study was undertaken using SSR and RAPD molecular markers. Data analysis was done on the Minitab 17.0 software. Significant variability was noted in all traits except in pod sizes, seed sizes and % infected seeds. About 33.3% of the accessions had a survival rate of ≥ 70.0% where 9/10 Inbred lines were found with overall yield (kg/ha) ranging from 4.0 ± 1.6 in Akwashiki-Doma to 516.8 ± 46.9 kg/ha in Samnut 24 × ICGV–91328. Five accessions (15.5%) had pathological indices of zero indicating no traces of any disease of any type and they included one landrace called Agric-Dazhogwa and four Inbred lines: Samnut 25 × ICGV–91317, Samnut 26 × ICGV–19324, Samnut 26 × ICGV–91328 and Samnut 26 × ICGV–91319. Coefficients of yield determination R2 by survivorship and pathological index were 50.6% and 15%, respectively. A fit model was established (Yield in kg/ha = –146 − 7.94 × Pi + 5.88 × S). Susceptibility to diseases depends on the type of variety (χ2(32) = 127.67, P = 0.00). Yield was significantly affected by BNR@30 (F = 5.47, P = 0.025, P < 0.05) and DSV@60*RUST@60 interaction effect (F = 4.39, P = 0.044, P < 0.05). The similarity coefficient ranged from 28.57 to 100 in plant morphology. Four varieties had no amplified bands with SSR primers whereas amplified bands were present only in four landraces accessions using the RAPD primer. The dendrogram generated by molecular data gave three groups where genetic similarity ranged from 41.4 to 100.0. The Inbred lines were noted for their high survivorship, good yield and disease resistance. Samnut 24 × ICGV–91328, an inbred line, had the highest yield but was susceptible to diseases. Among the landraces, Agric-Musha, Bomboyi-Dugu and Agric-Dazhogwa were selected for high survivorship and disease resistance. The selected inbred lines and landraces are valuable genetic resources that may harbour useful traits for breeding and they should be presented to the growers based on their unique agronomic values. The highest yielding inbred lines should be improved for resistance to late leaf spot diseases while the outstanding landraces should be improved for yield.

Yield response of accessions of Bambara groundnut (Vigna subterranea (L) Verdc) inoculated with Bradyrhizobium japonicum strains

Field experiments were conducted in two different agroecological locations of Ibadan and Ikenne in Nigeria from August through December during the 2019 and 2020 cropping seasons. The studies were set up to reduce reliance on inorganic nitrogen fertilizer and to embrace the use of nitrogen-fixing bacteria to improve legume production to increase farmers' output and profitability. Ten accessions of the Bambara groundnut (BGN) were used in the trials. Seeds of each BGN accession were coated with each of the following Bradyrhizobium japonicum strains (B. japonicum): FA3, RACA6, USDA110, and IRJ2180A before planting. Furthermore, Nitrogen (N) fertilizer (20 kg/ha, urea) was applied to seedlings without inoculation, and uninoculated seedlings (without inoculation and without fertilization) served as control. The experiment was, therefore, a factorial arrangement (10 BGN accessions, 4 B. japonicum strains, N fertilizer application, and an uninoculated control). The yield and yield components of the inoculated BGN accessions were significantly enhanced at both agroecological locations and seasons. Among the B. japonicum strains used for inoculation, RACA6 strains significantly enhanced the yield and yield component of TVSu-1698 than other inoculated BGN accessions with a mean value of 6,234 ± 87 kg ha−1 recorded in both locations and seasons, compared to the result obtained in the combination of TVSu-1698 with N fertilizer with a mean value of 3,264 ± 943 kg ha−1. By using TVSu-1698 with RACA6 strain, farmers can get 85% more yield than on average with other genotypes/strains combination, while an average yield of 60% could be obtained by farmers using N fertilizer application.

Yield Components and Yield Stability Performance of Some Nigerian Accessions of Bambara Groundnut [Vigna subterranea (L.) Verdc.] in Six Environments

Background: Bambara groundnut accessions over the years had been unstable in its yield potentials with contrasting yield inferences, factors not limited to variety, soil types and nutrients, climate change, time had been bottlenecks for scientist to breakthrough in stability research. Field experiments were conducted in three years at two locations to assess and identify accessions with stable yield and determine the relationship between yield and yield components. Methods: Seeds of 100 accessions of Bambara groundnut of Nigerian origin were obtained from the genebank of the Genetic Resources Center, IITA in 2017. Randomized complete block design (RCBD) was used in the evaluation for three years in two locations. PROC ANOVA procedure on the statistical analytical system (SAS, 9.4) was used to determine significant differences and stability equation was used to identify yield stable index. Result: Correlation showed that seven yield contributing traits had positive and significant correlation with yield per hectare. Yield stability analysis indicated nine of the selected accessions were stable in the expression of its yield potentials in the environments and years. This study showed that selection for high yielding and stable accessions could be useful for further utilization of genetic resources in achieving food security.

GROUNDNUT GENOTYPES’ DIVERSITY ASSESSMENT FOR YIELD AND OIL QUALITY TRAITS THROUGH MULTIVARIATE ANALYSIS

Genetic variability is essential in plant breeding for crop adaptation in a specific environment, enhancing yield potential, creating resistance to biotic and abiotic stresses, improving quality attributes, and most importantly, selecting desirable and better parents for hybridization programs. The study was designed to ascertain the genotypic diversity of 54 accessions of groundnut (Arachis hypogaea). The study evaluated these accessions/genotypes for 13 different traits (morphological, yield, and oil quality) under the rainfed climate of Pakistan. Significant differences were observed for all studied traits. Likewise, significant difference in the percent coefficient of variability (CV%) was also found for these traits. The research included classifying the genotypes further into six different clusters using the Ward method. Principal component analysis was performed that showed variability in components for different traits. The first five principal components (PCs) showed an eigenvalue of more than one that contributed about 71.83% of the total observed variation. Major characters accounted for by PC1 included pod weight per plant, grain weight per plant, and the number of pods per plant. PC2 positively contributed to oleic acid and shelling percentage, PC3 contributed positively to dry pod yield, plant height, and days to flower initiation, and PC4 contributed for days to 50% flowering, the number of pods per plant, and dry pod yield. These data on genotypic diversity for studied traits in the recent investigation will help breed new groundnut lines to strengthen germplasm sources for cultivar development in rainfed areas of Pakistan.

Effect of Bradyrhizobium japonicum Strains and Inorganic Nitrogen Fertilizer on the Growth and Yield of Bambara Groundnut (Vigna subterranea (L.) Verdc) Accessions

This study was set up to compare the inoculation of Bradyrhizobium japonicum strains and the application of nitrogen (N) fertilizers (urea with 46% nitrogen) on the growth and yield of Bambara groundnut accessions. The study results suggest that the benefits of Bradyrhizobium japonicum (B. japonicum) strain inoculation are greater and that the strain could reduce reliance and the excess amount spent by farmers to procure inorganic fertilizers and avoid the negative effect of N fertilizer on the environment after its use. Field studies were conducted in two different geographical locations, in Ibadan (Ib) and Ikenne (Ik), Nigeria, during the rainy season between August and December in 2019 and 2020. The experiment was arranged in a randomized complete block design (RCBD) in both locations and seasons and was replicated three times, with each block representing each replicate. It had a 10 × 6 factorial arrangement with one block holding the 10 accessions of Bambara groundnut inoculated with four B. japonicum strains. The second block had N fertilizer application and the third control block was without inoculation or fertilizer application. The 10 accessions of Bambara groundnut used in the study were as follows: TVSu-378, TVSu-506, TVSu-787, TVSu-1606, TVSu-1698, TVSu-1739, TVSu-710, TVSu-365, TVSu-475, and TVSu-305. Six seeds of each accession were coated with each of the four B. japonicum strains, namely, FA3, USDA110, IRJ2180A, and RACA6, before planting them in the field in both locations during the rainy season. In the next block, urea as N fertilizer (46% nitrogen) was applied to the uninoculated seedlings of accessions of Bambara groundnut 2 weeks after planting (WAP). The third block was the control with zero inoculation and zero fertilizer application. Data collected were subjected to an analysis of variance and mean and were separated using Duncan's Multiple Range Test (DMRT) at a p > 0.05 level of probability. It was found that FA3 inoculation significantly enhanced the growth traits of the accessions than other strains and N fertilizer application. In both locations and seasons, at 7 weeks after planting (WAP) and 12 WAP, plant height (19.54 and 22.71 cm), number of branches (33.63 and 62.77), number of leaves (116.54 and 209.25), terminal leaf length (5.62 and 6.00 cm), and width (2.09 and 2.56 cm) were recorded. The yield and yield components recorded at harvest were as follows: pod length (13.27 cm), pod width (9.08 mm), seed length (9.39 mm), seed width (6.92 mm), weight of 100 seeds (56.85 g), and yield/ha (750.72 kg). The yield and yield components were also significantly influenced by the inoculation of FA3 and RACA6 than other inoculated strains and N fertilizer application in both locations and seasons.

Genetic variability, heritability and association among yield components and proximate composition of neglected and underutilized Bambara groundnut [Vigna subterranea (L) Verdc] accessions for varietal development in Ghana

Bambara groundnut is an underutilized crop in Ghana with a lot of potential that can be harnessed to contribute to food and nutritional security in Ghana and Sub-Saharan African countries. The recent experiment was conducted to assess the genetic variability, heritability, and association among the yield components and the proximate composition of the Bambara groundnuts. Twenty-five (25) accessions of Bambara groundnut were sourced from different agro-ecological zones. The results from the analysis of variance showed a highly significant difference (p < 0.001) among almost all the traits studied. The estimate of the broad-sense heritability ranged from 12.50% to 84.458% for seed width and economic yield respectively. High heritability values accompanied by high GA were recorded for hundred seed weight (g), economic yield (g), biological yield (g), harvest index, and yield (kg). The separation of correlation coefficients into direct and indirect effects of component traits for yield traits revealed that traits such as economic yield and pod weight which were positively correlated with yield and exerted a high positive direct effect on yield could be selected for varietal development of Bambara groundnut in Ghana. The results from the proximate composition suggest that the Bambara groundnut accessions used in this study have high nutritional potentials that could serve in the alleviation of food security and nutritional problems when these accessions are selected for varietal development.

Genetic diversity in Bambara groundnut {Vigna subterranea (L.) Verdc.}

Abstract Bambara groundnut is a grain legume with enormous morphological variability. In order to genetically establish the variation that exists in this crop, an assessment of genetic diversity was therefore carried out with 20 accessions of Bambara groundnut collected from International Institute of Tropical Agriculture (IITA) Ibadan. The design of the experiment was randomised complete block design with three replications. Results from analysis of variance (ANOVA), and principal component analysis (PCA) showed outstanding genetic diversity among the collections. The first four principal components accounted for 91.89% of the total variability. Cluster analysis and the dendrogram discretely grouped the accessions into four genetically distinct groups. One accession TVSU 353 singly formed a group in cluster analysis and dendrogram, which implies that TVSU 353 was genetically distinct from the rest of the accessions. Morphological characters assessed provided a useful measure of genetic differences among Bambara groundnut accessions, which can facilitate identification and selection of potential breeding lines for crop improvement as well as germplasm conservation.

Genetic variability in morpho-agronomic traits of various accessions of Vigna subterranea (L.) Verdc.

Vigna subterranea is an indigenous African legume widely cultivated across the continent. It is a highly diverse crop exhibiting diversity in morpho-agronomic characteristics. This genetic diversity is also crucial for crop improvement as it determines which breeding strategy/ methodology to utilize in its improvement. The study evaluated the diversity in morpho-agronomic characteristics of different accessions of Bambara groundnut. ‘TVSu596’ exhibited the highest germination percentage (100 %) and shortest days to 50 % flowering (40 days) while ‘TVSu11’ had the highest number of leaves (146). Qualitative evaluation revealed the diversity existing in their morphological characteristics. Elemental analysis showed the accessions are rich in mineral elements and exhibit diversity. Principal component analysis revealed 83.37 % of total variations in morphological and yield traits by the first three principal axes. Traits such as number of leaves, petiole length, and days to 50 % flowering furnish most of the variations. Cluster analysis revealed the accessions clustered into 4 groups. These accessions are therefore recommended for utilization in development of improved cultivars or early-maturing varieties.

Selection for Yield Improvement in Bambara Groundnut (Vigna subterranea L. Verdc.)

Selection as the most practical and economical way of improving yield in an extreme autogamous crop was carried out in a Randomized Complete Block Design (RCBD) with three replications, with thirty three accessions of Bambara groundnut {Vigna subterranea (L.) Verdc}. Qualitative characters displayed a reasonable range of variation except for eye pattern, seed shape, pod texture and growth habit. The result on the analysis of variance (ANOVA) showed significant differences (p0.05) for all traits except for plant height, number of leaves per plant and seed length that were statistically insignificant. The principal component analysis result revealed that eight components (Eigen values ≥ 1) accounted for 78.36 % of the phenotypic variance, and quantitative traits revealed more phenotypic variation among the accessions Pearson’s correlation coefficient showed that petiole length (r= 0.64), vigour index (r= 0.49), seed length (r=0.53), canopy width (r=0.38), and internode length (0.58). had a high positive correlation with seed yield. Ranking of the accessions based on significantly strong correlated traits with yield using the rank summation index (RSI) method, and the selection of the best top 5% of the entries identified accessions TVSU 1688 and 1638 with RSI scores of 31 and 43 respectively as the best high yielding Bambara groundnut lines. Correspondingly, accessions TVSU 1688 and 1638 had the highest mean seed yield per plant of 1150.5g and 720.8g respectively in the 3-year field evaluation; which further confirmed the precision of the ranking and selection result. Invariably these two accessions were inherently high yielding Bambara groundnut accessions.

GENETIC DIVERSITY IN BAMBARA GROUNDNUT (Vigna subterranean) AS REVEALED BY MOLECULAR WEIGHTS OF THE SEEDS’ PROTEINS

Nine accessions of Bambara groundnut (Vigna subterranea (L.) Verdc.,syn. Voandzeia subterranea (L.) Thouars ex DC.) obtained from National Centre for Genetic Resources and Biotechnology (NACGRAB), Ibadan, Oyo state, were assessed for their genetic and phylogenetic relatedness through electrophoretic analysis of the seed proteins. 0.2g of the seeds were weighed and macerated with mortar and pestle in 0.2M phosphate buffer containing 0.133M of acid (NaH2PO4) and 0.067 of base (Na2HPO4) at pH 6.5. Protein characterization with standard marker revealed that the seeds of the nine accessions contained proteins (B.S.A, Oval Albumin, Pepsinogen, Trypsinogen and Lysozyme) with molecular weights ranging from 66kda and above, 45 – 65 kDa, 44 – 33 kda, 32-24 kDa and 23-14 kDa, respectively. The student T-test revealed that accessions B, C, E, F, H and I have molecular weights not significantly different from one another (P&lt;0.05) while samples A, D and G showed significantly different values (P&gt;0.05). All the accessions had at least two proteins and two major bands in common. The study revealed intra-specific similarities and genetic diversity in protein contents among the nine accessions of Bambara groundnut (Vigna subterraranea (L.) Verdc.syn

VARIATION MINERAL COMPOSITIONS OF SOME BAMBARA GROUNDNUT (VIGNA SUBTERRANEA (L.) VERDC.) ACCESSIONS

The study aimed to assess variation in mineral compositions of some accessions of Bambara groundnut (Vigna subterranea [L.] Verdc.) for domestic use and genetic enhancement. Twenty accessions of Bambara groundnut were planted in a Randomised Complete Block Design (RCBD) with three replications. The five minerals were analysed which include, calcium, magnesium, iron, zinc and manganese. These accessions showed significant (P?0.05) variations across the five mineral analysed. Accession no. 18 had the highest mean for iron (2.89 mg100g-1), Accession no. 12 had the highest mean value for zinc (0.65 mg100g-1) Accession no. 8 had the highest mean value for calcium (217.36 mg100g-1), magnesium (14.29 mg100g-1)and manganese (0.82 mg100g-1). However, accession no. 12 had the lowest mean values in four of the minerals except zinc. This result showed that some of these accessions could be selected for genetic enhancement of minerals, some for domestic use and some for industrial use.

Proximate Composition and Functional Properties of Some New Groundnut Accessions

Ten new accessions of groundnut (<i>Arachis hypogea</i>) were oven dried and processed into full fat powdered forms and analysed for the proximate and functional properties using AOAC official methods. The crude protein ranged 20.7-25.3%, crude fat 31- 46%, ash 1.2-2.3%, crude fiber 1.4 -3.9%, carbohydrate 21-37% and moisture 4.9-6.8 %. Energy values of the groundnut accessions were between 525 kcal/100g and 606 kcal/100g. The ash, moisture, carbohydrate, fat and fiber values of all groundnut accessions proved to be significantly different whereas there was no significant difference amongst the protein values at p ≤ 0.05. The bulk density ranged between 0.63 g/cm<SUP>3</SUP> and 0.88 g/cm<SUP>3</SUP> whereas water absorption capacities were between 20 % and 30 %. Swelling power ranged from 2.98 g/g to 4.18g/g and solubility index was between 26.5% and 57% with no significant difference at p ≤ 0.05. Foaming capacity ranged from 4.0-16.2 % and stability 94-100%. Samples showed a significant difference in terms of bulk density at p ≤ 0.05. The relatively high protein content of all the accessions as well as their functional properties make them a valuable protein supplement in weaning foods as well as the treatment of protein energy malnutrition cases.

Evaluation of Nutrient Parameters of Selected African Accessions of Bambara Groundnut (&lt;i&gt;Vigna &lt;/i&gt;&lt;i&gt;subterranea &lt;/i&gt;(L.) Verdc&lt;i&gt;.&lt;/i&gt;)

Developing countries, especially in Africa are facing challenges of malnourished conditions and food insecurity generally. Nutrients, being components of food ingredient required for survival, normal body function and satisfying the physiological and dietary requirements of the body metabolism [38]. Hence, for meaningful growth and developments in man, the type and amount of nutrients intake and its rate of absorption or level is crucial. However, much emphases and consumption pattern in Africa had been on common or routine food crops like rice, common beans, cassava, maize e.t.c., resulting in the reduced utilisation of other plant species, termed neglected and under-utilised species (NUS), like Bambara groundnut. Selected accessions of Bambara groundnut (Vigna subterranea (L.) Verdc), assembled at the International Institute of Tropical Agriculture, IITA, Ibadan, Nigeria were analysed for important nutrients parameters including moisture content, carbohydrate, protein, crude fibre, total sugar, fat, starch, ash and minerals, based on standard and established protocols at the Crop Utilisation laboratory, IITA, Ibadan, Nigeria. Moreso, samples were sent to the South African grain laboratory, the Willows, South Africa, for the determination of free and essential amino acids using HPLC and UPLC conditions. Results revealed that accessions TVSu – 1235, TVSu – 1231, TVSu – 1205, TVSu -729 and TVSu – 1824 could be regarded as high nutrients varieties, while TVSu – 1744, TVSu – 553 and TVSu - 922 are medium nutrients type, while the remaining accessions falls below the medium nutrient range, among these lines of Bambara groundnut evaluated. The protein values has a range of 15.88 ± 0.005 g / 100 g for TVSu – 1202 to 24.91 ± 0.011 g / 100 g for TVSu – 1231; while their carbohydrate content ranges from 42.77 ± 0.001 g / 100 g for TVSu – 1202 to 62.76 ± 0.223 g / 100 g for TVSu – 1744.

Morphological Variation in Selected Accessions of Bambara Groundnut (Vigna subterranea L. Verdc) in South Africa

&lt;p&gt;Bambara groundnut (&lt;em&gt;Vigna subterranea &lt;/em&gt;L. Verdc) is an underutilized crop in the African continent. It is a drought tolerant crop and fixes atmospheric nitrogen. Bambara groundnut is primarily grown for the protein content of its seeds and is mainly produced by small scale farmers at subsistence level. The objective of the study was to assess the morphological variation of landraces of bambara groundnut in South Africa. Thirty accessions of bambara groundnut were evaluated for their variability in agronomic and morphological traits. The field experiment was conducted at ARC-VOPI in Roodeplaat research farm during the 2014/2015 summer cropping season. The field trial was arranged as a complete randomized block design with three replications. Eighteen quantitative traits were recorded to estimate the level of genetic variability among accessions. The analysis of variance revealed significant differences among the phenotypic traits evaluated. The UPGMA cluster analysis based on the quantitative traits produced four distinct groups of genotypes and a singleton. Genotypes SB11-1A, SB19-1A, SB12-3B and Bambara-12 were found to possess good vegetative characters and are recommended for use as suitable parents when breeding cultivars for fodder production. Desirable yield and yield-related traits were identified in B7-1, SB4-4C, SB19-1A, Bambara-12 and SB16-5A and are recommended as suitable parental lines for bambara groundnut grain production improvement. The phenotypic characters therefore provide a useful measure of genetic variability among bambara genotypes and will enable the identification of potential parental materials for future breeding programs in South Africa.&lt;/p&gt;

Reactions of bambara groundnut accessions to photoperiods

In two light-controlled experiments conducted at the Teaching and Research Farm of the Department of Crop Science, Faculty of Agriculture, University of Nigeria, Nsukka, the effects of six photoperiods (8, 10, 12, 14, 16 hours and natural photoperiod) on growth and flower induction in six accessions of bambara groundnut (TVsu 1023, TVsu 745, TVsu 323/764, TVsu 11, TVsu 9 and Yaudu (local) were studied at two different periods of the year. In experiment one, the design used was a 6 x 6 factorial arrangement laid out in a completely randomized design (CRD) with 3 replications. The second experiment was a 5 x 6 factorial in CRD with three replications. In the first photoperiodic experiment (May 9, 1992 and August 10, 1992), Yaudu (local), TVsu 745, TVsu 11, TVsu 1023 and TVsu 9 showed a quantitative short day response to the number of leaves produced per plant, number of days to flower bud emergence and to anthesis. In the second growth chamber experiment (October 1992 to January 1993), TVsu 745, TVsu 764, TVsu 11, TVsu 1023 and Yaudu local exhibited a quantitative short day response in their number of days to flower bud emergence and to anthesis. As a result, they could be planted around July to take advantage of the short photoperiods of October to December for good crop.Key words: photoperiodism, bambara groundnut, accessions, anthesis, number of flowers, leaf area

Evaluation of some Accessions of Bambara Groundnut (Vigna Subterranean L. Verdc) for Resistance to Bruchid Infestation, Based on Grain Source and Seed Coat Colour

Abstract The relative susceptibility of different accessions of Bambara groundnut (Vigna subterranean L. Verdc) to Callosobruchus maculatus (F.) was assessed in a laboratory trial in Nigeria. Treatments were comprised factorial combinations of four grain sources from Nigeria (Enugu, Anambra, Benue and Kogi state) and three predominantly contrasting seed coat colours (black, brown, and milky-colour) laid out in a completely randomized design (CRD). There were four replications of each treatment. Egg depositions by adult C. maculatus were affected by grain sources such that ovipositions on those sourced from the state of Anambra were significantly (p &lt; 0.05) higher than those from other sources. Similarly, black coloured grains harboured more insects and eggs compared to other seed coat colours. Accesssions collected from Benue and/or those with a milky-coloured seed coat showed some levels of oviposition deterrence. However, the interaction of grain source and seed coat colour was not significant based on oviposition, adult emergence, and mortality counts. Grain sources and seed coat colour were, therefore, important traits to be considered while selecting ideotypes for resistance to C. maculatus

Genetic Divergence, Character Correlations and Heritability Study in 22 (Arachis hypogaea L.) Accessions of Groundnut

Twenty two groundnut genotypes collected from International Crops Research Institute for Semi Arid Tropics (ICRISAT) and local sources (Samaru, UNILORIN and UNAAB) were cultivated in Lagos (60º 36’N, 30º 34’E) and Abeokuta (70º 10’N, 30º 20’E) during 2010 planting seasons, to determine the genetic variability and performance of the genotypes. Data collected on ten (10) characters and yield was subjected to multivariate analysis to determine genetic divergence among the genotypes. Number of pods per plant showed significant positive correlation with yield per plant in both environments also had the largest direct positive effect on yield per plant (0.66, 0.70). Days to maturity showed the largest direct negative effect of -0.33 and -0.36 in Lagos 2003 and Abeokuta 2004 respectively. Heritability estimates ranged from 62.34% to 90.67 and 24.75 to 89.46 for number of branches per plant at flowering and days to maturity in (E1) Lagos and (E2) Abeokuta, respectively. The mean squares of the combined analysis of variance revealed significant genotypes and Genotype x Environment interactions on yield per plant.

Floral biology of Bambara groundnut (Vigna subterranea (L.) Verdc)

Investigation on floral biology of twelve accessions of Bambara groundnut [Vigna subterranea (L.) Verdc] was carried out in the greenhouse of the School of Agriculture and Agricultural Technology, Federal University of Technology, Owerri, Nigeria, in a completely randomized design with three replications. Significant varietal differences (P 0.05). Typical of flowering plants, the crop consists of vegetative and reproductive organs. The initiation of flower buds was between 30 and 48 days after planting (DAP) while the maturity of the flowers was between 34 and 52 DAP (3 to 5 days from flower bud initiation). Matured flowers for hybridization should be 2 to 3 days old from bud initiation and observed to be yellow or creamy in colour. The time taken for matured flower bud to open (anthesis) ranged between 12 to 20 h (which occurred between 07:00 and 10:00 h). Emasculation should be carried out on mature flower buds within 12 h of flower bud maturity as pollination takes place after this period. Key words: Floral biology, bambara groundnut, Vigna subterranea.

Variation and interrelationships for pod and seed yield characters in bambara groundnut (Vigna subterrenea) in Adamawa State, Nigeria

Entries of ten accessions of bambara groundnut were evaluated for variation and interrelationships for pod and seed yield characters in a randomized complete block design with three replication for two years. Seed and pod yield component characters were measured and evaluated. Significant differences (P<0.05) were recorded for seedling and seed yield characters. High broad sense heritability provides that to large extent additive genetic effects are more important that non additive and environmental influences. The number of nodules and effective nodules could effectively discriminate among the accessions evaluated. The number of trifoliate had the largest direct effect on pod yield, suggesting its influence on pod yield, while the number of effective nodules recorded the largest indirect effect on pod yield and its largest indirect effect through fodder weight/plant. The path analysis revealed the adverse effect of pod/plant on pod yield/ha-1 was largely due to indirect effect of plant height at flowering, fodder weight and number of effective nodules. The seed weight had the largest influence on seed yield/ha-1; this was masked by plant height at flowering and petiole length. Pod length could be a selection indicator for seed yield. The incorporation of these characters in existing accessions is practicable because of their relative importance. Key words: Association analysis, bambara groundnut, heritability, masking action, phenotypic variance, pod and seed yield ha-1.