Cassava roots are notable for their short shelf-life due to post-harvest physiological deteriorat... more Cassava roots are notable for their short shelf-life due to post-harvest physiological deterioration (PPD). PPD is initiated by mechanical damage, which typically occurs during harvesting and progresses from the proximal site of damage to the distal end, making the roots unpalatable within 72h. The short shelf-life severely limits marketing options by increasing losses, marketing costs, and limiting access to urban markets and processing centres. Reducing PPD of cassava roots is amongst top research priorities National Root Crops Research Institute (NRCRI) Umudike. Our main approaches NRCRI aimed at reducing Cassava PPD include conventional breeding, mutagenesis, molecular breeding and genetic engineering. Land races and exotic genotypes have been screened for delayed PPD. Limited variability was observed amongst land races in this trait. Thirty three genotype with delayed PPD at 7 days after harvesting (DAH) and 22 with delayed PPD at 14 DAH have been identified from backcross po...
Thirteen varieties of soybean (Glycine max (L) Merril) were grown during the late planting season... more Thirteen varieties of soybean (Glycine max (L) Merril) were grown during the late planting season in 1999 in a randomized complete block design with three replicates to evaluate genetic variability of some characters in soybean, and to study the' mutual association among nine characters viz: plot seed yield, number of plants harvested per plot, chaff weight! days to 50% flowering days to 50% maturity, weight of 300 seeds, pod length, plant height at harvest and pod shattering. Analysis of variance was used to determine if there is variation among the soybean genotypes for the agronomic characters evaluated. All the genotypes were found to be significantly different from one another. The plot means were separated using least significant difference. The mean of each genotype for each trait were found to be different from one another for all the characters evaluated. Simple correlation study was also employed to determine the degree of association of the characters with seed yield ...
For an effective and efficient crop breeding program, collection of good genotypes that provides ... more For an effective and efficient crop breeding program, collection of good genotypes that provides good agronomic background for the new variety to be developed must be available, and such genotypes must contain significant genetic variability for effective crop development. In order to determine the agronomic worth of a collection of sweetpotato genotypes so as to identify the superior ones under different agro-ecologies, and also to determine the extent of variability that exists among the genotypes, fifty-two genotypes were evaluated at Umudike (rainforest belt) and forty-eight at Otobi (humid guinea savannah) during the raining season using recommended protocols. While agronomic data were taken at 4 months after planting (MAP), sweetpotato virus disease (SPVD) incidence and severity scores were taken at 2 MAP. Results showed that significant (p<0.001) variation exists among the genotypes for all the traits except weight of unmarketable roots in both locations. Genotype PYT/12/0...
In a bid to identify trait preferences that influence the adoption of cultivars by farmers in div... more In a bid to identify trait preferences that influence the adoption of cultivars by farmers in diverse agro-ecologies, a study was conducted in the Rain Forest (Abia State) and the humid Guinea Savannah (Benue State) using structured questionnaires. The socio-economic characteristics of the respondents revealed that more females were involved in sweetpotato production in both States. However, there exists marked differences in age (more Benue sweetpotato farmers were older), educational background (Abia farmers more and better educated), and farming experience (Benue farmers more experienced). Majority of the farmers in both States shared similarities in their farm size (majority having <3.0ha) and number of cultivars planted on a farm (>1.0). However, the farmers from both agro-ecologies differed in their preferences for cultivar maturity time (99% of Benue farmers preferred early maturing, while as high as 43% preferred late maturing cultivars). For root shape, most Benue res...
American Journal of Experimental Agriculture, 2014
Aims: To determine; (1) the variability among the elite sweet potato lines for root processing qu... more Aims: To determine; (1) the variability among the elite sweet potato lines for root processing quality traits; (2) the heritability of each trait and the correlation among them; (3)the acceptability of the boiled and fried roots by sweet potato consumers; and (4) an easy-to-measure traits that are linked to consumer acceptability of sweet potato roots. Study Design: Completely randomized design with three replications. Place and Duration of Study: The National Root Crops Research Institute, Umudike, Nigeria. Methodology: Fourteen advanced sweet potato lines were evaluated for processing traits such as dry matter, starch yield, flour yield, peel-loss, and total carotenoid. Correlation analysis among the traits was carried out, and broadsense heritability for each trait was calculated. Sensory evaluation was carried out on roots of the lines using selected panelists. Culinary traits that most influenced acceptability of boiled and fried sweet potato 115 roots were determined using forward selection multiple regression analysis. Results: There was significant (P=.05) variation among the 14 advanced lines for dry matter, starch content, flour content and peel loss. Dry matter ranged between 24.16 and 34.17%, starch content between 17.58 and 22.0%, flour yield between 21.34 and 32.32% and peel loss between 18.17 and 24.01%. Correlation studies showed that dry matter had significant (P&lt;0.05) correlation with starch and flour yield. There were significant (P&lt;0.05) differences among the genotypes for root colour and general acceptability for boiled roots, and root colour, mouth-feel, taste, aroma and general acceptability for fried roots. Forward selection multiple regression analyses for boiled and fried sensory traits identified fresh root colour as an easy-to-select trait to breed for consumer acceptability. Conclusion: All the processing traits evaluated were heritable and most of them acceptable for boiled and fried food forms. The identification of root flesh colour as an easy-to-measure trait that influences consumer acceptability is a major achievement of this work.
Potato and sweetpotato in Africa: transforming the value chains for food and nutrition security, 2015
Sweetpotato, with a global annual planting area of approximately 9 million ha, is the second most... more Sweetpotato, with a global annual planting area of approximately 9 million ha, is the second most important tropical root crop. It is widely adapted, being grown in more than 110 countries. Early maturing varieties grow in 3-4 months. It is hardy and has multiple uses. Both roots and foliage are edible and provide energy and nutrients in diets. Distinct quality types have different uses, with orange-fleshed sweetpotato being valued for its extremely high provitamin A content, and other types used in varied fresh and processed forms. Sweetpotato is easily bred, as true seed is easily obtained and generation cycles are short. There are five objectives of this review. The first objective is to briefly describe recent production and utilization trends by region; the second is to review knowledge about the origin and genetic nature of sweetpotato; the third is to review selected breeding objectives. The fourth objective is to review advances in understanding of breeding methods, includin...
Sweetpotato [ Ipomoea batatas (L.) Lam.] productivity is dependent on the development of improved... more Sweetpotato [ Ipomoea batatas (L.) Lam.] productivity is dependent on the development of improved varieties which have desirable food quality attributes. Proximate and functional properties of twelve newly developed orange-fleshed sweetpotato breeding lines namely: F1M1/16 (UMUSPO/3 X TIS8164/16), F1MI/23 (UMUSPO/3 X TIS8164/23), F1M1/24 (UMUSPO/3 X TIS8164/24), F1M1/25 (UMUSPO/3 X TIS8164/25), F1M1/26 (UMUSPO/3 X TIS8164/26), F1M1/32 (UMUSPO/3 X TIS8164/32), F1M1/33 (UMUSPO/3 X TIS8164/33), F1M1/36 (UMUSPO/3 X TIS8164/36), F1M1/83 (UMUSPO/3 X TIS8164/83), F1M1/86 (UMUSPO/3 X TIS8164/86), F1M1/88 (UMUSPO/3 X TIS8164/88) and F1M1/91 (UMUSPO/3 X TIS8164/91) were investigated. Results obtained showed that the sweetpotato lines were high in dry matter (27.30 to 41.34%) and starch (16.38-27.66%) contents. The crude protein, fiber and ash contents varied significantly (p<0.05) among the genotypes. The sweetpotato flours had high bulk densities ranging from 0.92g/cm 3 (in FIM1/26) to 1....
Studies were conducted to screen newly collected sweetpotato germplasm for starch, flour, and fee... more Studies were conducted to screen newly collected sweetpotato germplasm for starch, flour, and feed quality traits. Fresh tuber and forage yields were evaluated in the first study using 13 genotypes while in the second study tuber dry matter (DM) and starch contents were investigated using 17 genotypes both in augmented incomplete block designs. In the third study, voluntary dry matter intake (VDMI) was determined in White Fulani cows fed with sole fresh sweetpotato forage in early lactation, and potential degradation trial in three rumenfistulated N’Dama steers using the in-sacco technique in a completely randomized design. Mean (±SE) fresh tuber yield (13.00 ± 0.471 t/ha) was higher (P < 0.01) in control than test genotypes (13.20 versus 12.94 t/ha) while, flour yield (35.71 ± 1.351) was lower in control than test genotypes (34.80 versus 38.74 g/100 g). Tuber DM ranged (P < 0.01) from 44.27 to 67.11 g/100 g, and starch content from 19.80 to 30.60 g/100 g, with a negative corr...
Sweet potato breeding in Africa, more especially in Nigeria, has mainly focused on improving prod... more Sweet potato breeding in Africa, more especially in Nigeria, has mainly focused on improving productivity on farmers' fields and on fresh root consumption. In order to target the breeding program, the study was conducted to estimate the magnitude of genotype × environment interaction (G × E) and to select stable and high yielding sweet potato genotypes for fresh root yield and root Cylas severity in two locations, and to identify the most discriminating and representative test environments in Nigeria. The 41 genotypes were evaluated across two diverse environments using a randomized complete block design (RCBD) with three replications. Data were collected on total number of roots per plant, number and weight of marketable roots per plant, fresh root yield, and root Cylas severity. The data were subjected to analysis of variance using the Generalized Linear Model procedure of SAS 9.2 where genotype was treated as a fixed factor and replication treated as a random variable. Stabil...
Studies were conducted to screen newly collected sweetpotato germplasm for starch, flour, and fee... more Studies were conducted to screen newly collected sweetpotato germplasm for starch, flour, and feed quality traits. Fresh tuber and forage yields were evaluated in the first study using 13 genotypes while in the second study tuber dry matter (DM) and starch contents were investigated using 17 genotypes both in augmented incomplete block designs. In the third study, voluntary dry matter intake (VDMI) was determined in White Fulani cows fed with sole fresh sweetpotato forage in early lactation, and potential degradation trial in three rumen-fistulated N'Dama steers using the in-sacco technique in a completely randomized design. Mean (±SE) fresh tuber yield (13.00 ± 0.471 t/ha) was higher (P < 0.01) in control than test genotypes (13.20 versus 12.94 t/ha) while, flour yield (35.71 ± 1.351) was lower in control than test genotypes (34.80 versus 38.74 g/100 g). Tuber DM ranged (P < 0.01) from 44.27 to 67.11 g/100 g, and starch content from 19.80 to 30.60 g/100 g, with a negative...
Cassava roots are notable for their short shelf-life due to post-harvest physiological deteriorat... more Cassava roots are notable for their short shelf-life due to post-harvest physiological deterioration (PPD). PPD is initiated by mechanical damage, which typically occurs during harvesting and progresses from the proximal site of damage to the distal end, making the roots unpalatable within 72h. The short shelf-life severely limits marketing options by increasing losses, marketing costs, and limiting access to urban markets and processing centres. Reducing PPD of cassava roots is amongst top research priorities National Root Crops Research Institute (NRCRI) Umudike. Our main approaches NRCRI aimed at reducing Cassava PPD include conventional breeding, mutagenesis, molecular breeding and genetic engineering. Land races and exotic genotypes have been screened for delayed PPD. Limited variability was observed amongst land races in this trait. Thirty three genotype with delayed PPD at 7 days after harvesting (DAH) and 22 with delayed PPD at 14 DAH have been identified from backcross po...
Thirteen varieties of soybean (Glycine max (L) Merril) were grown during the late planting season... more Thirteen varieties of soybean (Glycine max (L) Merril) were grown during the late planting season in 1999 in a randomized complete block design with three replicates to evaluate genetic variability of some characters in soybean, and to study the' mutual association among nine characters viz: plot seed yield, number of plants harvested per plot, chaff weight! days to 50% flowering days to 50% maturity, weight of 300 seeds, pod length, plant height at harvest and pod shattering. Analysis of variance was used to determine if there is variation among the soybean genotypes for the agronomic characters evaluated. All the genotypes were found to be significantly different from one another. The plot means were separated using least significant difference. The mean of each genotype for each trait were found to be different from one another for all the characters evaluated. Simple correlation study was also employed to determine the degree of association of the characters with seed yield ...
For an effective and efficient crop breeding program, collection of good genotypes that provides ... more For an effective and efficient crop breeding program, collection of good genotypes that provides good agronomic background for the new variety to be developed must be available, and such genotypes must contain significant genetic variability for effective crop development. In order to determine the agronomic worth of a collection of sweetpotato genotypes so as to identify the superior ones under different agro-ecologies, and also to determine the extent of variability that exists among the genotypes, fifty-two genotypes were evaluated at Umudike (rainforest belt) and forty-eight at Otobi (humid guinea savannah) during the raining season using recommended protocols. While agronomic data were taken at 4 months after planting (MAP), sweetpotato virus disease (SPVD) incidence and severity scores were taken at 2 MAP. Results showed that significant (p<0.001) variation exists among the genotypes for all the traits except weight of unmarketable roots in both locations. Genotype PYT/12/0...
In a bid to identify trait preferences that influence the adoption of cultivars by farmers in div... more In a bid to identify trait preferences that influence the adoption of cultivars by farmers in diverse agro-ecologies, a study was conducted in the Rain Forest (Abia State) and the humid Guinea Savannah (Benue State) using structured questionnaires. The socio-economic characteristics of the respondents revealed that more females were involved in sweetpotato production in both States. However, there exists marked differences in age (more Benue sweetpotato farmers were older), educational background (Abia farmers more and better educated), and farming experience (Benue farmers more experienced). Majority of the farmers in both States shared similarities in their farm size (majority having <3.0ha) and number of cultivars planted on a farm (>1.0). However, the farmers from both agro-ecologies differed in their preferences for cultivar maturity time (99% of Benue farmers preferred early maturing, while as high as 43% preferred late maturing cultivars). For root shape, most Benue res...
American Journal of Experimental Agriculture, 2014
Aims: To determine; (1) the variability among the elite sweet potato lines for root processing qu... more Aims: To determine; (1) the variability among the elite sweet potato lines for root processing quality traits; (2) the heritability of each trait and the correlation among them; (3)the acceptability of the boiled and fried roots by sweet potato consumers; and (4) an easy-to-measure traits that are linked to consumer acceptability of sweet potato roots. Study Design: Completely randomized design with three replications. Place and Duration of Study: The National Root Crops Research Institute, Umudike, Nigeria. Methodology: Fourteen advanced sweet potato lines were evaluated for processing traits such as dry matter, starch yield, flour yield, peel-loss, and total carotenoid. Correlation analysis among the traits was carried out, and broadsense heritability for each trait was calculated. Sensory evaluation was carried out on roots of the lines using selected panelists. Culinary traits that most influenced acceptability of boiled and fried sweet potato 115 roots were determined using forward selection multiple regression analysis. Results: There was significant (P=.05) variation among the 14 advanced lines for dry matter, starch content, flour content and peel loss. Dry matter ranged between 24.16 and 34.17%, starch content between 17.58 and 22.0%, flour yield between 21.34 and 32.32% and peel loss between 18.17 and 24.01%. Correlation studies showed that dry matter had significant (P&lt;0.05) correlation with starch and flour yield. There were significant (P&lt;0.05) differences among the genotypes for root colour and general acceptability for boiled roots, and root colour, mouth-feel, taste, aroma and general acceptability for fried roots. Forward selection multiple regression analyses for boiled and fried sensory traits identified fresh root colour as an easy-to-select trait to breed for consumer acceptability. Conclusion: All the processing traits evaluated were heritable and most of them acceptable for boiled and fried food forms. The identification of root flesh colour as an easy-to-measure trait that influences consumer acceptability is a major achievement of this work.
Potato and sweetpotato in Africa: transforming the value chains for food and nutrition security, 2015
Sweetpotato, with a global annual planting area of approximately 9 million ha, is the second most... more Sweetpotato, with a global annual planting area of approximately 9 million ha, is the second most important tropical root crop. It is widely adapted, being grown in more than 110 countries. Early maturing varieties grow in 3-4 months. It is hardy and has multiple uses. Both roots and foliage are edible and provide energy and nutrients in diets. Distinct quality types have different uses, with orange-fleshed sweetpotato being valued for its extremely high provitamin A content, and other types used in varied fresh and processed forms. Sweetpotato is easily bred, as true seed is easily obtained and generation cycles are short. There are five objectives of this review. The first objective is to briefly describe recent production and utilization trends by region; the second is to review knowledge about the origin and genetic nature of sweetpotato; the third is to review selected breeding objectives. The fourth objective is to review advances in understanding of breeding methods, includin...
Sweetpotato [ Ipomoea batatas (L.) Lam.] productivity is dependent on the development of improved... more Sweetpotato [ Ipomoea batatas (L.) Lam.] productivity is dependent on the development of improved varieties which have desirable food quality attributes. Proximate and functional properties of twelve newly developed orange-fleshed sweetpotato breeding lines namely: F1M1/16 (UMUSPO/3 X TIS8164/16), F1MI/23 (UMUSPO/3 X TIS8164/23), F1M1/24 (UMUSPO/3 X TIS8164/24), F1M1/25 (UMUSPO/3 X TIS8164/25), F1M1/26 (UMUSPO/3 X TIS8164/26), F1M1/32 (UMUSPO/3 X TIS8164/32), F1M1/33 (UMUSPO/3 X TIS8164/33), F1M1/36 (UMUSPO/3 X TIS8164/36), F1M1/83 (UMUSPO/3 X TIS8164/83), F1M1/86 (UMUSPO/3 X TIS8164/86), F1M1/88 (UMUSPO/3 X TIS8164/88) and F1M1/91 (UMUSPO/3 X TIS8164/91) were investigated. Results obtained showed that the sweetpotato lines were high in dry matter (27.30 to 41.34%) and starch (16.38-27.66%) contents. The crude protein, fiber and ash contents varied significantly (p<0.05) among the genotypes. The sweetpotato flours had high bulk densities ranging from 0.92g/cm 3 (in FIM1/26) to 1....
Studies were conducted to screen newly collected sweetpotato germplasm for starch, flour, and fee... more Studies were conducted to screen newly collected sweetpotato germplasm for starch, flour, and feed quality traits. Fresh tuber and forage yields were evaluated in the first study using 13 genotypes while in the second study tuber dry matter (DM) and starch contents were investigated using 17 genotypes both in augmented incomplete block designs. In the third study, voluntary dry matter intake (VDMI) was determined in White Fulani cows fed with sole fresh sweetpotato forage in early lactation, and potential degradation trial in three rumenfistulated N’Dama steers using the in-sacco technique in a completely randomized design. Mean (±SE) fresh tuber yield (13.00 ± 0.471 t/ha) was higher (P < 0.01) in control than test genotypes (13.20 versus 12.94 t/ha) while, flour yield (35.71 ± 1.351) was lower in control than test genotypes (34.80 versus 38.74 g/100 g). Tuber DM ranged (P < 0.01) from 44.27 to 67.11 g/100 g, and starch content from 19.80 to 30.60 g/100 g, with a negative corr...
Sweet potato breeding in Africa, more especially in Nigeria, has mainly focused on improving prod... more Sweet potato breeding in Africa, more especially in Nigeria, has mainly focused on improving productivity on farmers' fields and on fresh root consumption. In order to target the breeding program, the study was conducted to estimate the magnitude of genotype × environment interaction (G × E) and to select stable and high yielding sweet potato genotypes for fresh root yield and root Cylas severity in two locations, and to identify the most discriminating and representative test environments in Nigeria. The 41 genotypes were evaluated across two diverse environments using a randomized complete block design (RCBD) with three replications. Data were collected on total number of roots per plant, number and weight of marketable roots per plant, fresh root yield, and root Cylas severity. The data were subjected to analysis of variance using the Generalized Linear Model procedure of SAS 9.2 where genotype was treated as a fixed factor and replication treated as a random variable. Stabil...
Studies were conducted to screen newly collected sweetpotato germplasm for starch, flour, and fee... more Studies were conducted to screen newly collected sweetpotato germplasm for starch, flour, and feed quality traits. Fresh tuber and forage yields were evaluated in the first study using 13 genotypes while in the second study tuber dry matter (DM) and starch contents were investigated using 17 genotypes both in augmented incomplete block designs. In the third study, voluntary dry matter intake (VDMI) was determined in White Fulani cows fed with sole fresh sweetpotato forage in early lactation, and potential degradation trial in three rumen-fistulated N'Dama steers using the in-sacco technique in a completely randomized design. Mean (±SE) fresh tuber yield (13.00 ± 0.471 t/ha) was higher (P < 0.01) in control than test genotypes (13.20 versus 12.94 t/ha) while, flour yield (35.71 ± 1.351) was lower in control than test genotypes (34.80 versus 38.74 g/100 g). Tuber DM ranged (P < 0.01) from 44.27 to 67.11 g/100 g, and starch content from 19.80 to 30.60 g/100 g, with a negative...
Uploads