Evaluation of Ten Cassava Varieties for Resistance to Cassava Mosaic Disease in Burkina Faso

Achieving food security for an ever-increasing human population requires faster development of improved varieties. To this end, assessment of genetic gain for key traits is important to inform breeding processes. Despite the improvements made to increase production and productivity of cassava in Uganda at research level, there has been limited effort to quantify associated genetic gains. Accordingly, a study was conducted in Uganda to assess whether or not genetic improvement was evident in selected cassava traits using cassava varieties that were released from 1940 to 2019. Thirty-two varieties developed during this period, were evaluated simultaneously in three major cassava production zones; central (Namulonge), eastern (Serere), and northern (Loro). Best linear unbiased predictors (BLUPs) of the genotypic value for each clone were obtained across environments and regressed on order of release year to estimate annual genetic gains. We observed that genetic trends were mostly quadratic. On average, cassava mosaic disease (CMD) resistance increased by 1.9% per year, while annual genetic improvements in harvest index (0.0%) and fresh root yield (−5 kg per ha or −0.03% per ha) were non-substantial. For cassava brown streak disease (CBSD) resistance breeding which was only initiated in 2003, average annual genetic gains for CBSD foliar and CBSD root necrosis resistances were 2.3% and 1.5%, respectively. It’s evident that cassava breeding has largely focused on protecting yield against diseases. This underpins the need for simultaneous improvement of cassava for disease resistance and high yield for the crop to meet its current and futuristic demands for food and industry.

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ROOT ROT RESISTANCE IN NEW CASSAVA VARIETIES INTRODUCED TO FARMERS IN NIGERIA

Experimental Agriculture ◽

10.1017/s0014479708006777 ◽

2009 ◽

Vol 45 (1) ◽

pp. 15-24 ◽

Cited By ~ 5

Author(s):

R. U. OKECHUKWU ◽

A. G. O. DIXON ◽

M. O. AKORODA ◽

M. MWANGI ◽

R. BANDYOPADHYAY

Keyword(s):

Root Rot ◽

Matter Content ◽

Mosaic Disease ◽

Cassava Mosaic Disease ◽

Resistant Variety ◽

Environment Interaction ◽

Dry Matter Content ◽

Humid Forest ◽

New Varieties ◽

Cassava Varieties

SUMMARYIn 2004 and 2005 through field trials in over 2500 locations in several agroecological zones, 40 new cassava varieties were introduced in Nigeria. The trials were managed by scientists, extension workers and farmers. The aim in introducing these new varieties was to pre-emptively manage cassava mosaic disease, to avert an imminent threat from the Ugandan strain of the pathogen and prevent damage to the Nigerian cassava economy. From these trials, 10 new varieties were selected and officially released for high root yield, high dry matter content and acceptability for food, industry and livestock. Cassava root rot is a major source of yield loss in Nigeria, especially where farmers practice late harvest because they wait for a good price from the market before harvest and sales. This paper investigated how the 40 varieties together with three old improved varieties currently in farmers' fields during the formal trials responded to root rot disease. No absolutely resistant variety was found, indicating that early harvest (9–11 months after planting) is still the best way to reduce losses from root rot. Root rot is also significantly (p ≤ 0.05) influenced by genotype and environment interaction. Most root rot was recorded in the humid forest and the least was in the Sudan savanna agroecological zone. Using a rank-sum method, the 43 varieties were separated into highly resistant, resistant, moderately resistant, moderately susceptible, susceptible and highly susceptible classes.

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Evaluation of Newly Released Cassava Varieties for Yield Performance, Reactions to Cassava Diseases and Farmers’ Preference in Adjumani District of Uganda

Journal of Agricultural Science ◽

10.5539/jas.v13n4p84 ◽

2021 ◽

Vol 13 (4) ◽

pp. 84

Author(s):

Alex Abaca ◽

Emmanuel Odama ◽

Alfred Komakech ◽

Baron Asiku ◽

Andema A. Andrews ◽

...

Keyword(s):

Mosaic Disease ◽

Cassava Mosaic Disease ◽

Yield Performance ◽

Foliar Symptoms ◽

Information Gap ◽

Root Necrosis ◽

Cassava Brown Streak Disease ◽

New Varieties ◽

Rot Disease ◽

Cassava Varieties

Cassava viral diseases particularly cassava brown streak disease (CBSD) and cassava mosaic disease (CMD) have put pressure on cassava breeders to develop varieties that are resistant/tolerant to them. Several cassava varieties have been rolled out to farmers with the latest being NAROCASS series that are tolerant to these diseases. The yield performance of these new varieties have not been documented in some sub zones like Adjumani district that falls within a major West Nile agro-ecology of Uganda. Therefore this study sought to established yield performances of, reactions to major diseases, and farmers’ preference to these newly released cassava varieties in Adjumani. Results showed significant (P ≤ 0.05) differences among cassava varieties and experimental sites for all the parameters evaluated. Average yield performance by varieties were in the order of a local cassava—Alifasia (8.7 t/Ha) lowest, NAROCASS 2 (18.55 t/Ha), NASE 14 (33.97 t/Ha), NASE 19 (41.26 t/Ha), and NAROCASS 1 (41.71 t/Ha) highest. CMD foliar symptom was present at all sites on a local cassava—Alifasia, and on NAROCASS 1 in Ayiri parish, Ukusijoni sub-county. CBSD foliar symptoms were observed on off-types (TME 14) in the plot of NASE 14 in Miniki Parish only whereas CBSD root necrosis was observed at all sites on the local cassava—Alifasia, and on NASE 19 in Maaji parish, Ukusijoni sub-county. Cassava root rot disease was localised in Ukusijoni sub-county only. Farmers’ preferences to these newly released cassava varieties were in the order of NASE 19 (40.96%), NAROCASS 1 (24.86%), NAROCASS 2 (15.82.28%), NASE 14 (15.54%), and a Local cassava—Alifasia (2.83%). Result from this study strengthens the information gap in the breeding process towards developing a cassava variety with farmer-preferred attributes, and can also inform the utilisation of these improved cassava varieties in Adjumani district.

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Assessing Reactions of Genetically Improved and Local Cassava Varieties to Cassava Mosaic Disease (CMD) Infection in a Savannah Region of the DR-Congo

American Journal of Plant Sciences ◽

10.4236/ajps.2013.44101 ◽

2013 ◽

Vol 04 (04) ◽

pp. 824-837 ◽

Cited By ~ 3

Author(s):

Marcel Muengula-Manyi ◽

Lyna Mukwa ◽

Kabwe K. Nkongolo ◽

Patrick Tshilenge-Djim ◽

Stephan Winter ◽

...

Keyword(s):

Mosaic Disease ◽

Cassava Mosaic Disease ◽

Dr Congo ◽

Genetically Improved ◽

Cassava Varieties

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CHEMICAL, PASTING AND SENSORY PROPERTIES OF TAPIOCA GRITS FROM CASSAVA MOSAIC DISEASE-RESISTANT CASSAVA VARIETIES

Journal of Food Processing and Preservation ◽

10.1111/j.1745-4549.2009.00378.x ◽

2010 ◽

pp. no-no

Author(s):

JOY EKE ◽

SIMON ACHINEWHU ◽

LATEEF SANNI

Keyword(s):

Mosaic Disease ◽

Sensory Properties ◽

Cassava Mosaic Disease ◽

Disease Resistant ◽

Cassava Varieties

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Developing Cassava Mosaic Disease resistant cassava varieties in Ghana using a marker assisted selection approach

Euphytica ◽

10.1007/s10681-014-1262-6 ◽

2014 ◽

Vol 203 (3) ◽

pp. 549-556 ◽

Cited By ~ 3

Author(s):

Elizabeth Parkes ◽

Martin Fregene ◽

Alfred Dixon ◽

Emmanuel Okogbenin ◽

Bright Boakye-Peprah ◽

...

Keyword(s):

Marker Assisted Selection ◽

Mosaic Disease ◽

Cassava Mosaic Disease ◽

Disease Resistant ◽

Selection Approach ◽

Cassava Varieties

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Effects of Vector Maturation Time on the Dynamics of Cassava Mosaic Disease

Bulletin of Mathematical Biology ◽

10.1007/s11538-021-00921-4 ◽

2021 ◽

Vol 83 (8) ◽

Author(s):

F. Al Basir ◽

Y. N. Kyrychko ◽

K. B. Blyuss ◽

S. Ray

Keyword(s):

Time Delay ◽

Plant Density ◽

Plant Viruses ◽

Mosaic Disease ◽

Plant Diseases ◽

Cassava Mosaic Disease ◽

Maturation Time ◽

Negative Effect ◽

Dynamical Regimes

AbstractMany plant diseases are caused by plant viruses that are often transmitted to plants by vectors. For instance, the cassava mosaic disease, which is spread by whiteflies, has a significant negative effect on plant growth and development. Since only mature whiteflies can contribute to the spread of the cassava mosaic virus, and the maturation time is non-negligible compared to whitefly lifetime, it is important to consider the effects this maturation time can have on the dynamics. In this paper, we propose a mathematical model for dynamics of cassava mosaic disease that includes immature and mature vectors and explicitly includes a time delay representing vector maturation time. A special feature of our plant epidemic model is that vector recruitment is negatively related to the delayed ratio between vector density and plant density. We identify conditions of biological feasibility and stability of different steady states in terms of system parameters and the time delay. Numerical stability analyses and simulations are performed to explore the role of various parameters, and to illustrate the behaviour of the model in different dynamical regimes. We show that the maturation delay may stabilise epidemiological dynamics that would otherwise be cyclic.

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Development of a triple antibody sandwich enzyme-linked immunosorbent assay for cassava mosaic disease detection using a monoclonal antibody to Sri Lankan cassava mosaic virus

Virology Journal ◽

10.1186/s12985-021-01572-6 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Saengsoon Charoenvilaisiri ◽

Channarong Seepiban ◽

Mallika Kumpoosiri ◽

Sombat Rukpratanporn ◽

Nuchnard Warin ◽

...

Keyword(s):

Mosaic Virus ◽

Immunosorbent Assay ◽

Mosaic Disease ◽

Cassava Mosaic Disease ◽

Enzyme Linked Immunosorbent Assay ◽

Sri Lankan ◽

Stem Cuttings ◽

Field Samples ◽

Cassava Stem ◽

Cassava Mosaic Virus

Abstract Background Cassava mosaic disease (CMD) is one of the most devastating viral diseases for cassava production in Africa and Asia. Accurate yet affordable diagnostics are one of the fundamental tools supporting successful CMD management, especially in developing countries. This study aimed to develop an antibody-based immunoassay for the detection of Sri Lankan cassava mosaic virus (SLCMV), the only cassava mosaic begomovirus currently causing CMD outbreaks in Southeast Asia (SEA). Methods Monoclonal antibodies (MAbs) against the recombinant coat protein of SLCMV were generated using hybridoma technology. MAbs were characterized and used to develop a triple antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) for SLCMV detection in cassava leaves and stems. Assay specificity, sensitivity and efficiency for SLCMV detection was investigated and compared to those of a commercial ELISA test kit and PCR, the gold standard. Results A TAS-ELISA for SLCMV detection was successfully developed using the newly established MAb 29B3 and an in-house polyclonal antibody (PAb) against begomoviruses, PAb PK. The assay was able to detect SLCMV in leaves, green bark from cassava stem tips, and young leaf sprouts from stem cuttings of SLCMV-infected cassava plants without cross-reactivity to those derived from healthy cassava controls. Sensitivity comparison using serial dilutions of SLCMV-infected cassava sap extracts revealed that the assay was 256-fold more sensitive than a commercial TAS-ELISA kit and 64-fold less sensitive than PCR using previously published SLCMV-specific primers. In terms of DNA content, our assay demonstrated a limit of detection of 2.21 to 4.08 × 106 virus copies as determined by quantitative real-time PCR (qPCR). When applied to field samples (n = 490), the TAS-ELISA showed high accuracy (99.6%), specificity (100%), and sensitivity (98.2%) relative to the results obtained by the reference PCR. SLCMV infecting chaya (Cnidoscolus aconitifolius) and coral plant (Jatropha multifida) was also reported for the first time in SEA. Conclusions Our findings suggest that the TAS-ELISA for SLCMV detection developed in this study can serve as an attractive tool for efficient, inexpensive and high-throughput detection of SLCMV and can be applied to CMD screening of cassava stem cuttings, large-scale surveillance, and screening for resistance.

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