All rights reserved

Plano de Gestão de Resíduos - Centro Regional de Liderança da Mandioca: Malanje-Angola

An increasing multitude of insect pests and pathogens is targeting indigenous trees of natural forests, agroforestry systems, and exotic trees in planted forests in Africa. This is raising major concerns for a continent already challenged by adaptations to climate change, as it threatens a vital resource for food security of rural commu‐ nities, economic growth, and ecosystem conservation. The accidental introduction through trade of non‐native species in particular is accelerating, and it adds to the damage to tree‐based landscapes by native pests and diseases. Old‐time and new invaders heavily impact planted forests of exotic eucalypts, pines, and acacias, and are spreading quickly across African regions. But many non‐native pathogens are re‐ cently found affecting important indigenous trees. We describe the threat to African trees by providing an overview of highly relevant insect pests and diseases of indig‐ enous and exotic trees in Africa, and discuss implications for management and future research. The implementation of an integrated and globally coordinated approach based on improved biosecurity, biological control, and tree resistance would con‐ tribute to mitigate the potentially devastating impact of these invasions on African natural resources.

Africa: a new frontier for tree invaders?

Bemisia tabaci is an important vector of cassava brown streak viruses and cassava mosaic begomoviruses, the causal agents of cassava brown streak disease and cassava mosaic disease (CMD), respectively. A study was carried out to determine the genetic variability of B. tabaci associated with cassava and the occurrence of CMD in Zambia in 2013 and 2015. Phylogenetic analysis showed the presence of only the sub-Saharan Africa 1 (SSA1) genetic group in Zambia. The SSA1 population had three population subgroups (SGs): SSA1-SG1, SSA1-SG2 and SSA1-SG3. All three SSA1 population subgroups occurred in Western Province. However, only SSA1-SG3 occurred in Eastern Province, while only SSA1-SG1 occurred in North Western and Luapula Provinces. Adult B. tabaci were most abundant in Western Province in 2013 (11.1/plant) and 2015 (10.8/plant), and least abundant (0.2/plant) in Northern Province in both 2013 and 2015. CMD was prevalent in all seven provinces surveyed, with the highest incidence recorded in Lusaka Province in both 2013 (78%) and 2015 (83.6%), and the lowest in Northern Province in both 2013 (26.6%) and 2015 (29.3%). Although SSA1-SG1 occurred at greater abundances than the other subgroups, there was no direct association demonstrated between whitefly subgroup and incidence of CMD. Establishing which B. tabaci genetic groups and populations are associated with CMD and their distribution in the country is a key factor in guiding the development of CMD control strategies for cassava-dependent households.

Cassava (Manihot esculenta) is an important food crop across subSaharan Africa, where production is severely inhibited by two viral diseases, cassava mosaic disease (CMD) and cassava brown streak disease (CBSD), both propagated by a whitefly vector and via human-mediated movement of infected cassava stems. There is limited information on growers’ behavior related to movement of planting material, as well as growers’ perception and awareness of cassava diseases, despite the importance of these factors for disease control. This study surveyed a total of 96 cassava subsistence growers and their fields across five provinces in Zambia between 2015 and 2017 to address these knowledge gaps. CMD symptoms were observed in 81.6% of the fields, with an average incidence of 52% across the infected fields. No CBSD symptoms were observed. Most growers used planting materials from their own (94%) or nearby (<10 km) fields of family and friends, although several large transactions. over longer distances (10 to 350 km) occurred with friends (15 transactions), markets (1), middlemen (5), and nongovernmental organizations (6). Information related to cassava diseases and certified clean (diseasefree) seed reached only 48% of growers. The most frequent sources of information related to cassava diseases included nearby friends, family, and neighbors, while extension workers were the most highly preferred source of information. These data provide a benchmark on which to plan management approaches to controlling CMD and CBSD, which should include clean propagation material, increasing growers’ awareness of the diseases, and increasing information provided to farmers (specifically disease symptom recognition and disease management options).

Africa produces over half of global cassava; however, the continent’s average yield is below the potential yields achieved under experimental conditions. Many factors contributing to low yield  include lack of quality varieties, poor soils, limited access to capital, competition for labour, as well  as pests and diseases. Plant diseases are the major biotic constraints to cassava production and have  caused considerable food insecurity in Africa. Although there has been some level of disease  management which has contributed to the increase in cassava production, the two viral diseases:  cassava mosaic disease (CMD) and cassava brown streak disease (CBSD) still claim between 30- 16 40% and upto 70%, respectively of Africa’s cassava harvest. Given the importance of the two  diseases in Africa, we review the expansion of CBSD and CMD; impacts of the two diseases on food  security and how they can be managed. We provide insights in the spread of the two diseases,  management efforts, and future directions

Maize and groundnut are important crops for both commercial and smallholder farming in Zambia, whose production is being threatened by their susceptibility to aflatoxin contamination. Despite this threat, there is limited knowledge of household growers’ behaviour and applications related to suitable agricultural management practices, as well as growers’ perception and knowledge of aflatoxins and their effects. This limited knowledge has major implications for acute human health effects such as liver cirrhosis and death, cancer, stunting in children, immune system suppression, impaired food conversion, and reduced livestock productivity and/or increased livestock mortality. This cross-sectional survey of smallholder household growers in Zambia was conducted to identify the gaps in the knowledge and application of aflatoxin-associated agricultural management practices. A sample of 3865 maize- and groundnut-producing smallholder farm households were selected in 27 priority districts implementing the Scaling Up Nutrition (SUN)/First 1000 Most Critical Days Programme (MCDP) Phase II. Among the five pre-harvest management practices for maize and groundnuts – namely, controlling weeds, timely planting, controlling pests, and applying basal and top-dressing fertilisers – few households (8%) reported practising all of them. Among the recommended techniques for harvesting and handling maize and groundnuts, the most common harvest-management practices under maize production were drying (95.2% of households) and sorting at harvest (72%). In contrast, very few households (2%) practised at least three of four maize harvest management practices. Similarly, very few households (10%) practised at least 4 of the 6 groundnut harvest-management measures. Comparatively, post-harvest and storage management practices were more commonly practised, although most households did not practise all six post-harvest and storage management measures. Overall, very few households (1% for maize and 4% for groundnuts) were observed to be practising at least 12 of the 14 recommended management practices, implying that there are considerable gaps in the implementation of aflatoxin-related management practices along all stages of maize and groundnut production, consequently posing a significant threat to health and contributing to malnutrition levels in Zambia. As such, there is a need to develop tailored interventions and trainings for farming households, extension officers, and frontline health workers to prevent and manage aflatoxin contamination at different stages of crop production. Furthermore, the elimination of policy constraints, practical barriers of affordability and consumer awareness, and the value attached to the commercial product of Aflasafe, noted to reduce aflatoxin contamination by 80–100%, are of utmost urgency.

No âmbito do Projecto Agricultura Adaptativa ao Clima (Projecto AAC), financiado pela Ajuda Popular da Noruega (APN), o Instituto de Investigação Agrária de Moçambique (IIAM), a Associação Moçambicana para o Desenvolvimento Rural (AMDER) e a União Geral dos Camponeses de Nampula (UGCAN) desenvolveram um consórcio para implementação de suas actividades nos distritos de Angoche e Meconta, provincia de Nampula.

A news article on the review of agricultural science based programmes at the University of Zambia (UNZA) with support from MUSIKA, an institution which supports investments  in agricultural market, with a particular focus on smaller holder and emerging farmers. 

CCARDESA was established by SADC in 2010 to coordinate agricultural research and development in the region. Since then, the SADC Member States have maintained a high level of political commitment and a good appreciation of the importance of increased and sustained investment in agricultural research.