Leaves become shrivelled, mottled in serious cases 3. Check for the presence of mites on the underside of leaves 4. Green spider mites are very common pests in most African growing regions and become problematic during the dry season; can cause significant tuber losses. Plant tolerant cassava varieties where possible; plant at the beginning of the rainy season to encourage vigorous growth which allows plant to tolerate attack; intercropping with crops such as cowpea may reduce damage; introductions of the predatory mite Typhlodromalus aripo have been very successful at controlling the green spider mite in many regions of Africa.
This page is available in French. Content Content 1. Propagation 3. Diseases - Fungal. Pests - Insects. See questions about Cassava manioc.
Harvested cassava roots. Researcher working in cassava field. Cassava leaf. Cassava leaves. Cassava plants. Cassava plantation in the Democratic Republic of Congo. Planting cassava stem cuttings. Cutting cassava stems. Common Pests and Diseases Diseases. Symptoms of a severe anthracnose infection on cassava stem. Anthracnose canker on cassava stem. Cankers on stems and leaf petioles; leaves drooping downwards; wilting leaves which die and fall from plant leading to plant defoliation; death of shoots; soft parts of plant become twisted and distorted.
Disease emerges at the beginning of wet season Africa and worsens; spores spread by wind. Management Anthracnose usually does not cause large-scale economic damage to cassava and control is usually not necessary; avoid planting cuttings with cankers; if disease does occur crop debris should be removed and destroyed after harvest.
Brown Leaf Spot on cassava leaf in Chambezi, Tanzania. Management Remove leaves and crop debris from around plants to prevent disease spreading; remove weeds from around crop. Large, diffuse white spots on upper surface of leaves; spots with grey center on underside of leaves in humid weather. Prevalent in wetter, warmer regions where cassava is grown e. Brazil and Colombia; common in West Africa.
Cassava cuttings infected with witches broom disease. Symptoms of the disease include change in color of the stem and oozing from the stem. Shortened internodes. Witches' broom symptom. Plants are stunted with an excessive proliferation of branches; shoots have small leaves and shortened internodes; no chlorosis is present; cuttings from the shoots are weak but show no visible symptoms; few shoots successfully grow from cuttings. The disease will cause yield loss from 30 to 80 percent.
Management Remove and destroy and plants suspected of being infected; remove all cassava debris from field after harvest; disinfect all tools and equipment between cuttings. Patches of dark brown or gray fungal growth on stems; necrotic areas covering buds on the stem. Disease most commonly found on cassava grown in humid regions e. Management Only plant cassava cuttings taken from healthy plants which are free from necrotic lesions; space plants widely to allow good air circulation around plants and reduce disease incidence; remove weeds around plants; id disease is present, burn all necrotic stems and crop debris immediately after harvest to prevent spread.
Root symptoms of CBSD. Vorlachith 1 W. Add to favorites Download Citations Track Citations. View article. The author s declare no conflict of interest. References: Cuellar, W. Version 2. Google Scholar Dutt, N. Bioinformatics Virus Res. Rose mosaic disease appears in the spring, usually only on a portion of the plant Fig. It is easy to miss or mistake symptoms because they show up early in the season on the first sets of new growth and become obscured by subsequent growth.
Typical symptoms are ring spots,chlorotic line patterns Fig. Yellow net and yellow mosaic patterns can also develop. In some cultivars, RMVc causes a color-breaking, mottled effect in flowers. A typical mode of disease transmission is through grafting diseased tissue or buds onto diseased rootstock.
This disease is unlikely to spread via contaminated pruning tools, insect vectors, or plant-to-plant irritation plants rubbing against each other. Once inside the host, the virus travels to the roots, becomes systemic, and moves throughout the entire plant.
Onile-ere , a, b and Justin S. Pita c. Oghenevwairhe P. Olabode A. Justin S. Author information Article notes Copyright and License information Disclaimer. Eni: gn. South West and North Central Nigeria: Assessment of cassava mosaic disease and field status of African cassava mosaic virus and East African cassava mosaic virus.
Annals of Applied Biology , September , aab. Open in a separate window. Data Description The dataset provided with this submission contains field and laboratory results of samples collected during surveys conducted in and across the South West and North Central regions of Nigeria Fig.
Table 1 Number of fields surveyed per state. Dataset documentation The dataset is provided as long form tables in an excel file with three worksheets as contained in Table 2. Table 2 Details of worksheets in the provided dataset. Table 3 Description of variables contained in the dataset provided. Column could be used as id column to merge data from other worksheets Numeric - Country Country of survey.
Scoring rubric is in the methods section. This variable was calculated as follows. See methods section. Exploration of dataset Here we present an exploration of the dataset, all codes used for this exploration are available as a supplementary python script and Jupyter notebook. Experimental Design, Materials and Methods 2.
Survey We conducted surveys of cassava farms across the South West and North Central regions of Nigeria in and Sampling Sampling was performed following previously described methods with slight modifications [1]. Molecular Detection of Cassava Mosaic Begomoviruses 3. Table 4 List of Primers used in detecting Cassava mosaic begomoviruses.
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