Variation in Pod Yield Characters and Heritability Estimates in Some Cultivars of Bambara Groundnut (Vigna subterranea (L.) Verdc.

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1 Academic Journal of Plant Sciences 5 (): 50-55, 0 ISSN IDOSI Publications, 0 DOI: 0.589/idosi.ajps Variation in Pod Yield Characters and Heritability Estimates in Some Cultivars of Bambara Groundnut (Vigna subterranea (L.) Verdc. 3 P.M. Jonah, B. Aliyu, A.M. Kadams and D.T. Wamannda Department of Crop Science, Adamawa State University, P.M.B. 5 Mubi, Nigeria Department of Crop Production and Horticulture, Federal University of Technology, Yola Adamawa State, Nigeria 3 Adamawa State Collage of Agriculture Ganye, Adamawa State Nigeria Abstract: Variation in pod and seed yield among twelve cultivars of Bambara groundnut was investigated in 004 and 005 cropping seasons. The mean performance revealed that BG7004AS despite its recorded low number of pods per plant, had the highest 00 seed weight, pod width, pod length, seed width and seed length, followed by BG700AS, BG7009BS and BG7000AS, which had the best yield and yield component attributes, indicating their suitability for hybridization. The analysis of variance revealed significant differences (p<0.05) among the cultivars for most of the characters evaluated. The genotypic coefficient of variation ranged from 3.9 for height at 8 weeks after sowing to 6.5 for 00 seed weight, while the phenotypic coefficient of variation ranged from 4.93 for shelling percentage to 6.56 for 00 seed weight. Furthermore, estimates genotypic and phenotypic coefficient of variation as well broad sense heritability was also high for characters in 004 relative 005. Seed length, pod length and pod width recorded 00% broad sense heritability estimates and high genetic advance, indicating that these characters are under additive genetic control and selection for improvement will be worthwhile and may rapidly contribute to seed yield in bambara groundnut cultivars. Key words:genetic Advance Heritability Genotypic And Phenotypic Coefficient Of Variation Seed Yield And Variation INTRODUCTION Genetic studies in bambara groundnut is limited in sub Sahara Africa, this trend is associated with little Bambara groundnut (Vigna subterranea (L.) Verdc) preference for this crop among researchers in sub Sahara belongs to the fabaceae, subfamily papilionoideae [, ]. Africa, often termed Orphan crop. Little attempts have It is the third most important grain legume after groundnut been made to improve this crop through conventional (Arachis hypogea L.) and cowpea (Vigna unguiculata) in breeding and selection, because the crop is an important Sub-Sahara Africa [3]. The annual world production is staple and economic among farmers. Most cultivated 330,000t, 45-50% of which are produced in West Africa varieties in sub Sahara Africa are largely products of (Nigeria, Niger, Burkina Faso, Chad, Cote d Ivoire, Ghana introduction and selection, while hybridization in this crop and Mali) []. Bambara groundnut is cultivated primarily is limited. In genetic studies, characters with high for its subterranean pods [4]; rich in protein which helps genotypic coefficient of variation indicate the potential for to alleviate nutritional disorders in human and livestock an effective selection. Yield has been identified as a [5]. Immature seeds of bambara groundnuts are often complex character; associated with some yield boiled and eaten as a snack; vegetable milk and fermented contributing characters and are polygenic [8]. Genetic products such as (Parkia biglobosa (Jacq.) can be made variability in a base population plays an important role in from the seeds. Bambara groundnut fixes atmospheric any crop breeding program. The extent of diversity in the nitrogen through symbiosis with Rhizobium bacteria and population determines the magnitude of selection. therefore beneficial in crop rotations and intercropping Characters that influence yield are quantitatively inherited [6, 7] and production constraints of the crop in Nigeria and are influenced by interaction with the environment. includes: poor quality seeds, poor nodulation, low For breeding program to improve pod yield in bambara germination, instability in fodder and seed yield. groundnut, it is essential that plant characters that Corresonding Author: P.M Jonah, Department of Crop Science, Adamawa State University, P.M.B. 5 Mubi, Nigeria. 50

2 Acad. J. Plant Sci., 5 (): 50-55, 0 Table : Description of the cultivars used in the study. Entry name Local name Area of collection State General characteristics BG700BS Danngwaji Gwoza Borno Creamy colour, dominated by black stripes, smooth shiny seed coat with white eye BG700AS Gurlela Mubi Adamawa Creamy colour, oval shaped with smooth shiny seed coat and white-eye, which is surrounded by sky-blue colour. BG7003AS Idon Kule Mubi Adamawa A creamy colour having few spotted light brown colour, smooth shiny seed coat with white-eye, surrounded by patches of light brown/black colour. BG7004AS Bambwus Mubi Adamawa Creamy colour, having brown stripes, smooth shiny seed coat, white eye surrounded by sky blue colour BG7005AS Tanyanyi Mubi Adamawa Light brown having dotted black colours, oval shaped, smooth shiny seed with white eye. BG7006BS Kara Magdanda Gwoza Borno Brown colour seed with creamy patches mostly surrounding the eye, oval shaped with white eye BG7007BS Indara Ayaghayagha Gwoza Borno Completely black, oval shaped, smooth seed coat with white-eye. BG7008AS KwadaZwalang Hong Adamawa Completely white, round shaped, smooth shiny seed with white-eye. BG7009BS Wacha Ghagha Gwoza Borno Creamy colour, having black stripes, smooth shiny seed coat, with white-eye that is surrounded by blue/brownish colour. BG7000AS Kurvu Hong Adamawa Completely dark red, oval shaped shiny smooth seed coat with white-eye. BG700AS Wada hoba shen Hong Adamawa Light brown shiny seed coat with white-eye. BG700BS Achaghwaghwa Gwoza Borno Creamy colour, round shaped with white eye surrounded by dark brown colour having few brown stripes. determine productivity be identified. Therefore, the as recommended by Hepper [9], benlate (Benomyl) was information on the nature and extent of genetic variability th th sprayed at the rate of 30g/0L of water, at 5 and 6 weeks and transmission of traits is of paramount importance in after sowing. Data was collected on all the plants within enhancing the efficiency of selection for seed and pod the two middle rows. Characters measured includes: plant yield. This study was undertaken to estimate the extent of emergence and emergence percentage at weeks after genetic variability, heritability and relationships between sowing. Plant height (cm) at 8 weeks after sowing was the various yield components in bambara groundnut, in measured on ten randomly selected plants within the two order to formulate an effective breeding program for high middle rows. Prior to harvest, the number of plants was yielding cultivars in the tropics. estimated. The number of pods per plant was the mean number of pods of ten randomly selected plants, and pod MATERIALS AND METHODS yield per plant was taken as the mean number of harvested pods of ten randomly selected plants after Entries of twelve cultivars of Bambara groundnut drying. Seed yield per plant was estimated as the average (Table ) used in this evaluation were sourced from weight (g) of seeds of the ten randomly selected plants on farmers collection in the north eastern Nigeria; they had each plot after winnowing. While weight of hundred been maintained in the Department of Crop Science and seeds was estimated by weighing 00 clean and uniform are true-to-type. Five cultivars namely BG700BS, seeds picked randomly from the bulk of seeds harvested BG7006BS, BG7007BS, BG7009BS and BG700BS were per plot. source from farmers collection in Gwoza, Borno State, Shelling percentage was computed = Nigeria. While BG700AS, BG7003AS, BG7004AS, Weight of dry seed ( g) 00 Weight of dry pods( g ). While pod width and length were BG7005AS, BG7008AS, BG7000AS andbg700as were sourced from farmers in Mubi/Hong; Adamawa state. measured (cm) using Venier calipers from ten randomly Field evaluation was carried out at the teaching and selected pods per plot. In the same vein both length and research farm, Adamawa State University Mubi, Nigeria width of seeds were determined. The seed yield (kg ha ) (0 3 N and 3 7 E), in July 004 and 005 cropping was determined on plot basis and this was computed for season. This period coincide with the planting season for seed yield per hectare. bambara groundnut in this location. Field experiment was The mean for each trait over three replication and two laid out in a randomized complete block design with three years was computed for each cultivar and submitted for replications, each plot was 0m and a total experimental area was 595m. The experimental site was ploughed and harrowed, two seeds of each cultivar were sown at 50cm between plants, a total of 64 plants were established per plot. Weeding was done manually using hand hoe at 4 and 8 weeks after sowing. Fertilizer application of 60kg super phosphate per hectare was applied shortly after planting statistic using PROC MEA using PROC GLM procedure of SAS [0]. Broad sense heritability was computed as specified by using the method of Singh and Chaudhary [] and Moll et al., [] as: H B = g p 5

3 Acad. J. Plant Sci., 5 (): 50-55, 0 Where H B = broad sense heritability, performance of the bambara groundnut cultivars over the years of evaluation. Several studies have highlighted the g = genotypic var iance presence of genotype by environment interaction in crops; in okra [4], cassava [5] and maize [6]. This necessitates the selection of crops for specific p = phenotypic variance environment, wherein stability over environments is poor. Therefore inconsistencies in seed yield and agronomic RESULTS AND DISCUSSION characters over years implied that farmers must have been discouraged by this phenomenon which might have Mean seed yield among the cultivars ranged between accounted for yield losses and 80. kg ha (Table ), this provides basis for Table 4 represents the mean, range, genotypic and selection among the cultivars. From the mean phenotypic coefficient of variation, estimates of broad performance, BG700AS, BG7009BS, BG7000AS and sense heritability (H B) and genetic advance of seed yield BG7004AS showed clear superiority in terms of yield and and related characters on yearly basis. The mean yield component attributes. These cultivars identified performance for most characters was higher in magnitude could be suitable for hybrid production by exploiting in 005 evaluation when compared with 004 evaluation. their high yielding potentials. The combined analysis of The number of pods per plant, weight of 00 seeds and variance (Table 3) for seed yield and other agronomic seed yield/ha were higher in magnitude as compared characters showed significant genotype effects for with 005 evaluation. The relative amount of variability in agronomic characters. Thus indicating that bambara a population is best expressed in term of genotypic cultivars were highly variable in performance for coefficient of variation, since this variable takes into agronomic characters. The presence of variability in crop account the mean values as well as the unit of is important for genetic studies and consequently measurement. The analysis of variation returned high improvement and selection. Significant year (Y) effects estimates of genotypic and phenotypic coefficient for (P<0.05) indicates the presence of variability in the weight of hundred seed in 004 than 005 evaluation. environmental variables (Temperature, rainfall, humidity, The lowest genotypic coefficient of variation was sunshine) for both years of evaluation (Table 5 and recorded for seed width in both years of evaluation. Fig.&). It had been noted that unpredictable changes in A high variability observed in this study can be exploited weather have been described as essential in crop by selection [7]. The relatively small difference observed improvement [3] Significant Genotype by Year between the PCV and GCV may be associated with genetic interaction (P<0.05) was observed for all characters difference for these characters. Similar results have been evaluated. Thus confirming inconsistencies in the reported in Abelmoschus esculentus [4]. Table : Mean seed yield and agronomic performance of twelve Bambara groundnut cultivars (Vigna Subterranea) sown in Mubi, Adamawa State, Nigeria (004 and 005) Entry name. GCwk GPwk Ht8wk(cm) SC PN/plt PYplt(g) SY/plt(g) 00wt(g) SP(%) PW(cm) PL(cm) SW(cm) SL(cm) SY/ha(t) BG700BS 37.50d 58.60d 5.5abcd 33.67d 5.00cd 56.0cd 38.68c 84.85cd 7.58a.43cd.98d.03e.6cd.63f BG700AS 53.50ab 83.58a 4.4bcd 5.50abc 57.35bc 87.05a 53.0a 90.85c 64.03d.64a.09c.09c.6cd.8a BG7003AS 47.00bc 7.5bc 5.5abc 46.7c 64.7a 58.3cd 38.70c 68.77f 7.3a.3g.53h.04de.3de.09bcdef BG7004AS 36.00d 56.8d 3.73de 34.00d 34.03e 60.63c 36.98c 37.8a 67.6bc.65a.3a.6a.5a.66f BG7005AS 56.7a 87.75a 5.5abcd 54.50ab 48.55d 43.73e 6.65d 55.0g 66.8cd.44cd.80e 0.99f.7e.5bcde BG7006BS 37.50d 83.60a 4.97abcd 5.50abc 45.98d 56.65cd 35.9c 8.8d 64.66cd.40d.78e.08cd.3c.69ef BG7007BS 53.7ab 83.07ab 6.7a 5.7abc 6.7ab 58.07cd 38.75c 7.90f 70.83a.g.64g 0.97f.3de.9cdef BG7008AS 5.83ab 8.58ab 4.08cde 5.83abc 46.67d 54.05cd 38.c 80.90de 63.50d.3e.70fg.06cde.9de.77ef BG7009BS 50.00abc 78.3abc 5.68abc 48.33abc 34.7e 53.7cd 38.3c 7.7b 70.5ab.46c.6a.9b.47ab.53ab BG7000AS 48.67abc 76.03abc 5.0abcd 54.83a 49.3d 68.48b 4.65bc 85.68cd 63.4d.54b.8b.06cde.45b.5bcd BG700AS 53.83ab 84.a 6.ab 5.83abc 66.30a 70.7b 45.67b 69.37f 7.0a.3e.7f 0.98f.8e.3bc BG700BS 44.50c 69.53c.75e 47.7bc 47.87d 5.60d 35.40c 74.3ef 70.55ab.4f.54h.06cde.de.84def Grand Mean Means in a column with the same letters do not differ significantly from each other at P = 0.05 Table 3: Combined analysis of variance for fourteen agronomic characters in Bambara gr oundnut (Vigna subterranea) for 004 and 005 cropping season Source of Variation D.F PEwk EPwk Ht8wk SC PN/plant PY/plant SY/plant 00wt SP PW PL SW SL SY/ha Year 84.90** ** ** 60.73** 89.46* * 40.06** Replication Genotype 49.70** 67.90** 6.0** 30.70** ** ** 33.60** ** 67.4** 0.84.** 0.458** 0.043** 0.087** 0.89** Genotype x Year ** ** 00.70* ** 0.45** ** 0.006* Error = Not significant, * = Significant at (P = 0.05), ** = Significant at (P = 0.0) PEWK = Plant emergence at WAS, EPWK = Emergence Percentage at WAS, Ht8WK = Height at 8WAS, SC = Stand Count Prior to harvest, PN/plant = Pod number per plant, PY/plant = Pod yield per plant, SY/plant = Seed yield per plant, 00wt = 00 seeds weight, SP= Shelling Percentage, PW = Pod width, PL = Pod length, SW = Seed width, SL = Seed Length, SY/ha = Seed yield/ha. 5

4 Acad. J. Plant Sci., 5 (): 50-55, 0 Table 4: Yearly mean, range, genotypic and phenotypic coefficient of variations, estimates of broad sense heritability (H )and genetic advance (GA) of seed B yield and related characters observed in 004 (Y ) and 005 (Y ) in Mubi, Adamawa State, Nigeria Characters Mean Range Genotypic Phenotypic Coefficient Variation Coefficient Variation Heritability (%) GA (%) Plant Emergence Y Y Emergence % Y Y Height at 8WAS Y Y Stand count Y Y Pods/plant Y Y Pod yield/plant Y Y Seed yield/plant Y Y seed wt Y Y Shelling % Y Y Pod width Y Y Pod length Y Y Seed width Y Y Seed length Y Y Seed yield/ha Y Y Table 5: Maximum and Minimum Temperatures, rainfall, relative humidity and sunshine hours during 004 and 005 wet seasons Month Days Max.Temp (ºC) Min.Temp (ºC) Rainfall (mm) Relative Humidity (%) Sunshine Hours 004 April May June July August Sept Oct Nov April May June July August Sept Oct Nov

5 Acad. J. Plant Sci., 5 (): 50-55, 0 ACKNOWLEDGEMENTS The authors acknowledge with thanks financial contributions from Adamawa State University, Nigeria in supporting this research. REFERENCES. Aremu, M.O, O. Olaofe, and E.T. Akintayo, 006. Chemical composition and physiochemical characteristics of two varieties of bambara groundnut Fig. : Metrological parameters of the experimental site, (Vigna subterranea) Flours. Journal of Applied 004 cropping season Sciences, 6(9): PROTA (Plant Resources of Tropical Africa), 006. Cereals and pulses. (Ed) M. Brink and G. Belay. PROTA Foundation, Netherlands, pp: Rachie, K.O. and P. Silvestre, 977. In: Food crop of low land tropics. C.L.A Leakey and J.B Wills (ed.), London (U.K). Oxford University press, pp: Linnmann, A.R. and S.A. Azam-Ali, 993. Underutilized Crops. Pulses and Vegetables. In: Fig. : Metrological Parameters of the Experimental site, Williams, J.T (ed) bambara groundnut 005 cropping season. (Vigna subterranea) Chapman and Hall, London, pp: Broad sense heritability (H B) was high for most 5. Massawe, F.J., M. Dickinson, J.A. Roberts and characters in year 005 relative to 004. Pod width and S.N. Azam-Ali, 00. Genetic diversity in bambara length and seed width recorded 00% H B in each year of groundnut (Vigna subterranea (L.) Verdc) land races evaluation. Allard [8] had noted that 00% heritability revealed by AFLP markers: published on NRC implies that the phenotype could provides a perfect Research press website at htpp:/genome.nrc.ca, measure of the genotype value and therefore such Canada. characters will respond to selection. Broad sense 6. Mukumbira, L.M, 985. Effects of rate nitrogen heritability estimates and genetic advance were high for fertilizer and previous grain legume crop on maize most characters, exception was recorded in plant height at yields. Zimbabwe Agric Journal, 8: eight weeks after seeding and seed yield ha, which 7. Karikari, S.K., O. Chaba and B. Molosiwa, 999. recorded moderate heritability estimates. This implies the Effects of intercropping bambara groundnut on Pearl presence of positive gene effects which are additive in millet,sorghum and Maize in Botswana. African Crop nature and governed by few major genes. And under Science J., 7: polygenic action, they will respond positively to selection 8. Kadams, A.M. and A.A. Sajo, 998. Variability and pressure. correlation studies in yield and yield components in It was concluded from this investigation that bambara groundnut (Vigna subterrenea L. Verdc). considerable amount of variation exists among bambara Journal of Applied Science and Management, groundnut cultivars for yield and yield components. : High heritability and genetic advance recorded for length 9. Hepper, F.N., 970. Bambara groundnut (Vigna and width of pods, seed length and width clearly indicates subterrenea). Field Crop Abstracts, 3: -6. that genetic improvement and selection procedure will be 0. SAS SAS user Guide. SAS Institute, Inc. worthwhile. However, moderate heritability for seed. Singh, R.K. and B.D. Chaudhary, 985. Biometrical yield/ha- suggests that considerable limitations for methods in quantitative genetic analysis. Kalyani improvement in yield will be encountered. Publishers New Delhi India, pp:

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