Phenotypic diversity and selection in biofortified cassava germplasm for yield and quality root traits

Abstract Increasing carotenoid content and improving other root quality traits has been the focus of cassava biofortification. This study aimed to i) evaluate the genetic variability for total carotenoid content (TCC), as well as for root yield and root quality attributes; ii) estimate potentially useful correlations for selection; and iii) select parents for breeding and estimate the genetic gain. Data from 2011 to 2020 of 265 cassava genotypes with cream and yellow roots were analyzed for dry matter content (DMC), shoot yield, fresh root yield (FRY), dry root yield (DRY), harvest index, average number of roots per plant, starch content, root pulp color, cyanogenic compounds, and TCC. The best linear unbiased predictions showed great phenotypic variation for all traits. Six distinct groups were formed for productive characteristics of root quality, mainly TCC, DMC and FRY. Only TCC showed high broad-sense heritability (\({h}^{2}\)= 0.72), while the other traits had low to medium magnitude (0.21 ≤ \({h}^{2}\) ≤ 0.60). TCC was strongly correlated with pulp color (r = 0.70), but null significance for DMC. The network analysis identified a clear separation between the agronomic and quality attributes of cassava roots. The selection of the 30 genotypes for recombination in the breeding program has the potential to raise TCC by 37.1% and reduce the cyanogenic compounds content by 19.4%, in addition to increasing FRY and DRY by 37.7% and 40.2%, respectively. This is the first consolidated study on the potential of germplasm for the development biofortified cassava varieties in Brazil.

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Yield traits as selection indices in seedling populations of cassava

Cropp Breeding and Applied Biotechnology ◽

10.1590/s1984-70332010000300002 ◽

2010 ◽

Vol 10 (3) ◽

pp. 191-196 ◽

Cited By ~ 11

Author(s):

Henry Fred Ojulong ◽

Maryke Tine Labuschagne ◽

Liezel Herselman ◽

Martin Fregene

Keyword(s):

Dry Matter ◽

Tuber Yield ◽

Selection Index ◽

Matter Content ◽

Root Weight ◽

Dry Matter Content ◽

Root Yield ◽

Breeding Scheme ◽

Selection Indices ◽

Root Quality

The cassava breeding scheme currently used is long, because initial stages concentrate mainly on improving yield, with root quality selection following later. To shorten the scheme, yield and root quality should be selected simultaneously, starting at the seedling nursery. In this study, a nursery comprising of eight cassava families and 1885 seedlings developed from parents adapted to three major agro-ecologies, were evaluated for yield related traits in Colombia. Percentage dry matter content (DMC) and harvest index produced similar ranking of the parents. Tuber yield, weight, and number showed potential of increasing yield through conventional breeding. A selection index including fresh root yield, percentage DMC, root weight and roots per plant, with heavier weights being assigned to root weight and roots per plant, should be used.

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ẢNH HƯỞNG CỦA NỒNG ĐỘ Na2SO3 ĐẾN MỘT SỐ GIỐNG SẮN TRIỂN VỌNG TẠI THỪA THIÊN HUẾ

Tạp chí Khoa học và công nghệ nông nghiệp, Trường Đại học Nông Lâm Huế ◽

10.46826/huaf-jasat.v4n3y2020.502 ◽

2020 ◽

Vol 4 (3) ◽

pp. 2012-2019

Author(s):

Nguyễn Đình Thi ◽

Thái Thị Hồng Mỹ ◽

Lê Thị Hương Xuân

Keyword(s):

Ethanol Production ◽

Dry Matter ◽

Starch Content ◽

Growth Yield ◽

Matter Content ◽

Dry Matter Content ◽

Root Yield ◽

Yield And Quality ◽

Cassava Varieties

Nghiên cứu ảnh hưởng của các nồng độ Na2SO3 (0, 100, 300, 500 ppm) đến 03 giống sắn KM 94, KM 21-12 và KM 444 trong năm 2019 tại vùng sinh thái gò đồi thị xã Hương Trà, tỉnh Thừa Thiên Huế nhằm mục đích xác định ảnh hưởng và nồng độ Na2SO3 phù hợp cho cây sắn. Kết quả đạt được là: 1) Phun Na2SO3 ở các nồng độ thí nghiệm đã tăng sinh trưởng thân - lá - củ, năng suất, chất lượng củ và hiệu quả kinh tế của 03 giống sắn thí nghiệm. 2) Tại nồng độ phun Na2SO3 từ 300 đến 500 ppm, so với đối chứng giống KM 94 tăng năng suất thực thu 19,5 - 20,2%, tỷ lệ sắn lát đạt 40,9 - 41,1%, hàm lượng tinh bột đạt 29,3 - 30,2% và năng suất ethanol tăng 23,6 - 26,6%; Giống KM 21-12 tăng năng suất thực thu 15,1 - 18,6%, tỷ lệ sắn lát đạt 40,5 - 41,0%, hàm lượng tinh bột đạt 29,7 - 29,8% và năng suất ethanol tăng 21,6 - 25,8%; Giống KM 444 tăng năng suất thực thu 18,4 - 19,9%, tỷ lệ sắn lát đạt 40,6 - 40,8%, hàm lượng tinh bột đạt 30,3 - 30,9% và năng suất ethanol tăng 24,9 - 25,7%. ABSTRACT The study on the effects of Na2SO3 concentrations (0, 100, 300, 500 ppm) on 03 cassava varieties (KM 94, KM 21-12 and KM444) was conducted in 2019 in hilly ecological area of Huong Tra town, Thua Thien Hue province to determine the effect and suitable concentration of Na2SO3 for cassava. The results showed that: 1) Spraying Na2SO3 at a rate of 640 liters/ha with experimental concentrations increased stem - leaf - root growth, yield and quality of roots and economic efficiency of all of 03 cassava varieties. 2) Spraying Na2SO3 at concentrations from 300 to 500 ppm, compared with the control, KM 94 increased root yield of 19.5 - 20.2%, dry matter content reached 40.9 - 41.1%, starch content reached 29.3 - 30.2% and ethanol production increased by 23.6 - 26.6%; KM 21 - 12 increased root yield of 15.1 - 18.6%, dry matter content reached 40.5 - 41.0%, starch content reached 29.7 - 29.8% and ethanol production increased by 21.6 - 25.8%; KM 444 increased root yield of 18.4 - 19.9%, dry matter content reached 40.6 - 40.8%, starch content reached 30.3 - 30.9% and ethanol production increased by 24.9 - 25.7%.

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Portable Spectroscopy Calibration with Inexpensive and Simple Sampling Reference Alternatives for Dry Matter and Total Carotenoid Contents in Cassava Roots

Applied Sciences ◽

10.3390/app11041714 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1714

Author(s):

Wilfred Abincha ◽

Ugochukwu N. Ikeogu ◽

Robert Kawuki ◽

Chiedozie Egesi ◽

Ismail Rabbi ◽

...

Keyword(s):

Dry Matter ◽

Near Infrared ◽

Sampling Procedure ◽

Matter Content ◽

Partial Least Square ◽

Least Square ◽

Carotenoid Content ◽

Dry Matter Content ◽

Total Carotenoid ◽

Total Carotenoid Content

The use of standard laboratory methods for trait evaluation is expensive and challenging, especially for low-resource breeding programs. For carotenoid assessment, rather than the standard HPLC method, these programs mostly rely on proxy approaches for quantitative total carotenoid content (TCC) assessment. To ensure data transferability and consistency, calibration models were developed using TCC iCheck and Chroma Meter proxy methods for the adoption of the alternative near-infrared phenotyping method in cassava. Calibration was developed for dry matter content (DMC) using a simple and inexpensive sampling procedure associated with the proxy TCC protocols. The partial least square (PLS) and random forest (RF) models were compared for the two traits, and the correlation (r) between the actual and predicted values in the training and validation (in bracket) sets of r = 0.85 (0.76) and r = 0.98 (0.82) with PLS and RF, respectively, for iCheck, and r = 0.99 (0.96) and r = 0.99 (0.96) with PLS and RF, respectively, for Chroma Meter, was obtained. The calibration result of r = 0.93 (0.83) and r = 0.99 (0.81) using PLS and RF, respectively, was obtained for DMC. This effort is valuable in carotenoids improvement and supports the ongoing effort in adopting portable spectrometers for rapid and cheap phenotyping in cassava.

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Combining Ability and Genetic Components of Yield Characteristics, Dry Matter Content, and Total Carotenoids in Provitamin A Cassava F1 Cross-Progeny

Agronomy ◽

10.3390/agronomy10121850 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1850

Author(s):

Elizabeth Parkes ◽

Olufemi Aina ◽

Akuwa Kingsley ◽

Peter Iluebbey ◽

Moshood Bakare ◽

...

Keyword(s):

Combining Ability ◽

Dry Matter ◽

Matter Content ◽

Provitamin A ◽

Carotenoid Content ◽

Dry Matter Content ◽

Root Yield ◽

Total Carotenoids ◽

Genetic Components ◽

Fresh Root

Cassava is an important root crop in sub-Saharan Africa, largely cultivated for its starchy edible roots. Biofortified cassava varieties with enhanced provitamin A carotenoid content (PVAC) developed through conventional breeding provide a solution for vitamin A deficiency among vulnerable communities. The aim of this study was to use diallel analysis of six provitamin A cassava genotypes to determine the combining ability, genetic components, heritability, and heterosis of the most important yield characteristics and total carotenoids. Genetic variability for measured characteristics were evident. Fresh root yield was mainly determined by non-additive genetic effects, while dry matter content and total carotenoids were determined by additive effects. Total carotenoids were negatively correlated with fresh root yield, indicating that selection for higher provitamin A content could reduce yield. Mid and higher parent heterosis was seen in some of the crosses for fresh root yield, dry matter content, and total carotenoids. Narrow sense heritability was moderate for fresh root yield and dry matter content, and was high for total carotenoids. This study indicated that yield and dry matter content can be improved in provitamin A cassava but that increased provitamin A content may carry a yield penalty.

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Genetic Analysis of Yield and Quality Characteristics in Provitamin A Hybrid Cassava Families in Ghana

Agronomy ◽

10.3390/agronomy11101911 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1911

Author(s):

Bright Boakye Peprah ◽

Elizabeth Yaa Parkes ◽

Peter Kulakow ◽

Angeline van van Biljon ◽

Maryke Tine Labuschagne

Keyword(s):

Combining Ability ◽

Dry Matter ◽

Matter Content ◽

Breeding Program ◽

Carotenoid Content ◽

Cassava Mosaic Disease ◽

Root Weight ◽

Dry Matter Content ◽

Total Carotenoid Content ◽

Large Numbers

Cassava is the most widely cultivated and consumed crop in Ghana. Malnutrition is endemic in cassava-producing regions of Africa, partly due to the low micronutrient content of this crop. The aim of this study was to generate genetic information on characteristics such as total carotenoid content, dry matter content, root weight and number, and cassava mosaic disease (CMD), and their possible combination in cassava clones, using a North Carolina II breeding scheme. Five genetically diverse yellow-fleshed clones at advanced selection stages, with CMD resistance, were used as females and two high dry matter content white-fleshed clones, selected from farmers’ fields in Ghana, were used as males. Ten F1 families were generated, and evaluated at two locations in Ghana. General combining ability (GCA) mean squares were larger than specific combining ability (SCA) mean squares for harvest index, CMD, and carotenoid content, indicating additive genetic effects. The positive significant correlations that were observed between pulp color and carotenoid content; carotenoid content and CMD; pulp color and CMD; and pulp color and cortex color, make the screening of large numbers of progenies possible in the cassava breeding program. This could allow breeders to combine carotenoid content and CMD at the early breeding stages through visual assessment of pulp color and CMD symptoms. Large numbers of genotypes can be evaluated and a few can be selected to be quantified for carotenoid content at later stages of the breeding program, to save costs. One of the parents (P6), showed positive GCA effects for carotenoid content, dry matter content, CMD and storage root weight, hence could be used as a parent to generate clones that combine carotenoid content and dry matter content.

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Variation in Nutritional Components in Roots From Ahipa (Pachyrhizus ahipa (Wedd.) Parodi) Accessions and an Interspecific Hybrid (P. Ahipa × P. Tuberosus (Lam.) Spreng.)

10.20944/preprints202111.0363.v1 ◽

2021 ◽

Author(s):

Eduardo O. Leidi-Montes ◽

Youssef Ech-Liach ◽

Sabina Rossini-Oliva ◽

Marten Sørensen

Keyword(s):

Amino Acids ◽

Organic Acids ◽

Interspecific Hybrid ◽

Dry Matter ◽

Matter Content ◽

Root Weight ◽

Dry Matter Content ◽

Promising Alternative ◽

Functional Components ◽

Root Quality

Among the many neglected underutilized species, tuberous Andean root crops like the ahipas (Pachyrhizus ahipa) constitute a promising alternative for increasing diversity in nutrient sources and food security at a regional level. In this study, we present the content of some functional compounds in tuberous roots from several ahipa accessions and the progenies of the interspecific hybrid X207 (P. ahipa × P. tuberosus). A significant objective was to determine protein and free amino acids in the roots to evaluate their food quality as protein supply. The interspecific hybrids have been found to possess the root quality to provide the crop with a higher dry matter content. The high dry matter content of the P. tuberosus Chuin materials is retained in the root quality of the hybrids. Food functional components like carbohydrates, organic acids, and proteins were determined in several ahipa accessions and a stable (non-segregating) progeny of the interspecific hybrid, X207. The X207 roots showed a significantly higher dry matter content and a lower content in soluble sugars, but no significant differences were found in starch content or organic acids compared to the ahipa accessions. About the root mineral contents, Fe and Mn concentrations in X207 were significantly raised compared to the average of ahipa accessions. Among the ahipa and the hybrid, no prominent differences in protein content or protein amino acids were found, being both partially defective in providing sufficient daily intake of some essential amino acids. Root weight, a central component of root yield, was significantly higher in X207, but thorough field studies are required to substantiate the hybrid’s superior yield performance..

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Genome-wide association mapping of correlated traits in cassava: dry matter and total carotenoid content

10.1101/102665 ◽

2017 ◽

Cited By ~ 1

Author(s):

Ismail Y. Rabbi ◽

Lovina I. Udoh ◽

Marnin Wolfe ◽

Elizabeth Y. Parkes ◽

Melaku A. Gedil ◽

...

Keyword(s):

Association Mapping ◽

Negative Correlation ◽

Dry Matter ◽

Matter Content ◽

Genome Wide Association ◽

Carotenoid Content ◽

Dry Matter Content ◽

Root Crop ◽

Genome Wide ◽

The Tropics

ABSTRACTCassava (Manihot esculenta (L.) Crantz) is a starchy root crop cultivated in the tropics for fresh consumption and commercial processing. Dry matter content and micronutrient density, particularly of provitamin A – traits that are negatively correlated – are among the primary selection objectives in cassava breeding. This study aimed at identifying genetic markers associated with these traits and uncovering the potential underlying cause of their negative correlation – whether linkage and/or pleiotropy. A genome-wide association mapping using 672 clones genotyped at 72,279 SNP loci was carried out. Root yellowness was used indirectly to assess variation in carotenoid content. Two major loci for root yellowness was identified on chromosome 1 at positions 24.1 and 30.5 Mbp. A single locus for dry matter content that co-located with the 24.1 Mbp peak for carotenoid content was identified. Haplotypes at these loci explained a large proportion of the phenotypic variability. Evidence of mega-base-scale linkage disequilibrium around the major loci of the two traits and detection of the major dry matter locus in independent analysis for the white- and yellow-root subpopulations suggests that physical linkage rather that pleiotropy is more likely to be the cause of the negative correlation between the target traits. Moreover, candidate genes for carotenoid (phytoene synthase) and starch biosynthesis (UDP-glucose pyrophosphorylase and sucrose synthase) occurred in the vicinity of the identified locus at 24.1 Mbp. These findings elucidate on the genetic architecture of carotenoids and dry matter in cassava and provides an opportunity to accelerate genetic improvement of these traits.CORE IDEASCassava, a starchy root crop, is a major source of dietary calories in the tropics.Most varieties consumed are poor in micronutrients, including pro-vitamin A.These two traits are governed by few major loci on chromosome one.Genetic linkage, rather than pleiotropy, is the most likely cause of their negative correlation.

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Quality characterization, phenolic and carotenoid content of new orange, cream and yellow-fleshed sweetpotato genotypes

Horticultura Brasileira ◽

10.1590/s0102-0536-20210309 ◽

2021 ◽

Vol 39 (3) ◽

pp. 299-304

Author(s):

Lucimeire Pilon ◽

Jaqueline S Guedes ◽

Bruna S Bitencourt ◽

Raphael Augusto de C Melo ◽

Larissa PC Vendrame ◽

...

Keyword(s):

Phenolic Compounds ◽

Ipomoea Batatas ◽

Dry Matter ◽

Matter Content ◽

Soluble Solids ◽

Carotenoid Content ◽

Total Phenolic ◽

Dry Matter Content ◽

Total Carotenoids ◽

Β Carotene

ABSTRACT Sweetpotato (Ipomoea batatas) is a root crop grown in many countries. This tuberous root is a source of energy, nutrients, and phytochemicals. In this study, bioactive compounds and physical and physicochemical qualities of sweetpotato genotypes were evaluated. Eight new genotypes of sweetpotato produced by Embrapa Hortaliças (orange-fleshed: MD09026-OF and MD09024-OF; cream-fleshed: MD09011-CF, MD09004-CF, MD10039-CF, and MD10004-CF; yellow-fleshed: MD09017-YF and MD12002-YF) and two cultivars used as controls (Beauregard and Brazlândia Roxa) were evaluated for color, soluble solids, dry matter, phenolic compounds, total carotenoids and β-carotene. Hue angles differed even between those sweetpotatoes with the same flesh color. The orange-fleshed genotypes MD09024-OF, MD09026-OF, and Beauregard, had the lowest L*, showing to be darker than the others. These sweetpotatoes also had the brightest flesh colors with higher C*. The orange-fleshed genotypes MD09026-OF and MD09024-OF were sweeter (10.55oBrix and 9.23oBrix) than Beauregard (5.12oBrix). Brazlândia Roxa had the highest dry matter content (38.05%), followed by the genotypes MD10004-CF, MD09017-YF, MD09026-OF MD10039-CF, and MD09011-CF, which showed similarity, ranging from 32.33% to 29.12%. The highest contents of total carotenoids were found for the orange-fleshed genotypes MD09026-OF (80.06 mg g-1) and MD09024-OF (70.56 mg g-1) and Beauregard (73.12 mg g-1). These same genotypes showed the highest total phenolic compounds (0.815 mg g-1 and 0.686 mg g-1, respectively). MD09026-OF showed the highest content of β-carotene (46.47 mg g-1). MD09026-OF was the most prominent genotype among those evaluated, as it showed the highest total carotenoid, β-carotene, phenolic compounds, and soluble solids content, in addition to a high dry matter content.

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Cassava shrunken-2 homolog MeAPL3 determines storage root starch and dry matter content and modulates storage root postharvest physiological deterioration

Plant Molecular Biology ◽

10.1007/s11103-020-00995-z ◽

2020 ◽

Cited By ~ 1

Author(s):

Getu Beyene ◽

Raj Deepika Chauhan ◽

Jackson Gehan ◽

Dimuth Siritunga ◽

Nigel Taylor

Keyword(s):

Dry Matter ◽

Starch Content ◽

Matter Content ◽

Dry Matter Content ◽

Dry Matter Accumulation ◽

Storage Root ◽

Storage Roots ◽

Leaf Phenotype ◽

Root Starch ◽

Postharvest Physiological Deterioration

Abstract Key message Among the five cassava isoforms (MeAPL1–MeAPL5), MeAPL3 is responsible for determining storage root starch content. Degree of storage root postharvest physiological deterioration (PPD) is directly correlated with starch content. Abstract AGPase is heterotetramer composed of two small and two large subunits each coded by small gene families in higher plants. Studies in cassava (Manihot esculenta) identified and characterized five isoforms of Manihot esculenta ADP-glucose pyrophosphorylase large subunit (MeAPL1–MeAPL5) and employed virus induced gene silencing (VIGS) to show that MeAPL3 is the key isoform responsible for starch and dry matter accumulation in cassava storage roots. Silencing of MeAPL3 in cassava through stable transgenic lines resulted in plants displaying significant reduction in storage root starch and dry matter content (DMC) and induced a distinct phenotype associated with increased petiole/stem angle, resulting in a droopy leaf phenotype. Plants with reduced starch and DMC also displayed significantly reduced or no postharvest physiological deterioration (PPD) compared to controls and lines with high DMC and starch content. This provides strong evidence for direct relationships between starch/dry matter content and its role in PPD and canopy architecture traits in cassava.

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