By
N. Lutaladio
Agricultural Officer (roots and tubers) AGPC, FAO
|
NB. This paper was presented as a Powerpoint presentation and is provided as a separate file. Below are the summaries of this presentation in English and French and a printout of the text of the presentation. |
Summary
FAO is the only source of comparative statistical data across countries. Special effort has been made into the collection of reliable statistics for major export and food crops, in particular for crops such as cereals which are easier to monitor through the marketing chain. But it has not been easy to deal with root and tuber crops when it comes to producing reliable data. This complicates the long term monitoring of trends and impact for root and tuber crops in solving problems of Food Security and in alleviating Poverty. This may also affect policy analysis as well as the planning and management of food supplies.
Root and tuber crops especially cassava, potato, sweet potato, yam, taro and tannia contribute significantly to human food availability in developing countries in Africa, Asia and the Pacific, and Latin America and the Caribbean. They are also used for animal feed and various industrial applications. Their broad agro-ecological adaptability and adaptation to marginal environments, great flexibility in mixed farming systems, ability to produce reasonable yields where most crops cannot and their capacity to provide high quantity of carbohydrates make them the basis for food security at household level.
In developing statistical methodology for root and tuber crops, one must take into account some of the major agronomic aspects related to these crops such as long growth period for cassava, continuous planting and harvesting, mixed cropping and mixture of varieties, storage in the ground and post-harvest life and associated crop losses and damages, and leaf harvesting for human consumption.
Sampling units for estimating planted area and yield data at farmers' field should not only represent the administrative settings of a particular country but they should take into the account the existing agro-ecological zones. Wherever leaf consumption and/or marketing are important, data collection and yield estimates should also include the weight of leaves.
Baseline information collected through surveys should provide a better assessment of root and tuber crops productivity by farmer and production estimates should not overlook certain occurring events such as an outbreak of disease or pest and mass propagation and distribution of improved and proven varieties.
Résumé
Le FAO est de loin la seule véritable source comparative des données statistiques a travers les pays. Des efforts consistants ont été cependant faits en vue de recueillir des données statistiques pour la majorité des plantes destinées a la fois l'exportation et a la consommation, en particulier s'agissant des plantes comme les céréales qui sont assez faciles a faire le suivi au-delà des circuits du marché.
Néanmoins, il n'en a pas ainsi été le cas pour les plantes-racines et tubercules lorsqu'il s'agit de produire des données statistiques fiables. Ceci va ainsi compliquer un suivi a long terme de la tendance par rapport à la courbe de production puis celui de son apport sur la production des plantes-racines et tubercules, dans la résolution des problèmes relatifs à la sécurité alimentaire et dans la réduction de la pauvreté.
Ceci va ainsi avoir des effets sur les analyses politiques des Autorités de l'Etat tant sur la planification que sur la gestion de l'approvisionnement en aliments.
Les plantes-racines et tubercules plus spécialement le manioc, la patate-douce, l'igname, le taro, et la tannia contribuent remarquablement a la disponibilité du stock des Aliments dans les pays en développement en l'occurrence: en Afrique, Asie, Pacifique, L'Amerique Latine, et les Caraibes. Ils sont aussi utilises dans la nutrition des animaux puis dans la plupart des productions industrielles. Leur capacité' parfaite d'adaptation agro-écologique et mieux encore dans les environnements hostiles; leur grande flexibilité dans les systemes agricoles mixtes; leur capacité de produire des rendements raisonnables contrairement a la majorité des plantes; enfin leur capacité de fournir une grande quantité d'energie carborifiques font aussi d'elles la base de la securité alimentaire au niveau des menages.
En développant la méthodologie des données statistiques pour les plantes-racines et tubercules, l'on se doit de tenir compte des aspects agronomiques lies a celles-ci tels que: la longue période de croissance pour le manioc, les récoltes continues, la culture des plantes mixtes, le mixage des variétés, la conservation des plantes dans le sous-sol, la vie post-récolte, les destructions et les pertes des plantes, et enfin la récolte des feuilles pour la consommation doivent tous être pris en considération.
Les unités d'échantillonnage mis sur pied pour estimer la surface plantée et la collecte des données statistiques auprès des planteurs dans leur champ ne devraient pas seulement représenter les fixations administratives d'un pays particulier mais plutôt elles devraient prendre en compte les zones agro-écologiques existantes. La ou la consommation et/ou sa commercialisation sont importantes, la collecte des données statistiques, et l'estimation du rendement devrait aussi inclure le poids des feuilles.
La platforme d'informations recueillies a travers les sondages devrait fournir une meilleure évaluation de la production des plantes-racines et tubercules par les planteurs; puis cette estimation de la production ne devrait pas négliger certains aleas tels que: le ravage des maladies ou les pestes de meme que celui concernant la distribution des varietes testees et ameliorees.
Agronomic Aspects of Roots &Tubers
- Importance in Estimating Production -
Expert Consultation on Root Crops Statistics
Harare, Zimbabwe, 3-6 December 2002
by
N.B. Lutaladio, Agricultural Officer (roots & tubers)
FAO/AGPC
Food Insecurity in the World
Growth Rate and Edible Energy
A Vision for Roots & Tubers
“By 2020, Roots & Tubers will be integrated into the emerging markets through the efficient and environmentally sound production of diversified range of high-quality, competitive products for food, feed, and industry (Scott et al., 2000)”.
In 1994, FAO launched the SPFS to help developing countries to improve food security on an economically and environmentally sustainable basis. Under this initiative Roots & Tubers deserve special attention.
Contribution to Achieving the Vision
Root & Tubers
broad agro-ecological adaptability and adaptation to marginal environments
great flexibility in mixed farming systems
ability to produce reasonable yields where most crops can not, makes them the basis for food security at household level.
FAO and Partners
application of science and transfer of technology
dissemination of information, tools and methodologies
policy support and strengthening of national systems.
Major Species of Roots & Tubers: Cassava, Potato, Sweetpotato, Yam, Taro, Tannia
Main Agronomic Characteristics
Yield Determinants
Growth Development - Cassava
Growth Development - Potato
Overview of Statistics - Cassava
Overview of Statistics - Taro
Yield Potential and Gaps - Sweetpotato
Important Factors and Variables for Estimating Production:
1. Agro-ecological Zones
administrative setting and units - farming population per unit
latitude, longitude and altitude - location of farms
climate/weather - rainfall and length of seasons
vegetation - savannah, forest
soil/terrain - acid soil/volcanic soil; flat/sloppy/swampy
2. Seasonal or Annual Surveys
general assessment of crop productivity by farmers
collection of data - land size and use system; tools and inputs; population density; results of on-farm trials
consult with research/meteorological stations
3. Planted Area
final cropped area for the year (i.e., 0.25 ha)
planting time - replanting - double cropping or ratoon crop - intercropping or mixed stands
weather conditions at planting (delayed/insufficient/excessive)
supply/availability of planting material and other inputs
planting affected by population displacement or migration
4. Yield Data from Farmers' Field
samples of actual whole root/tuber fresh weight at final harvest
yield estimates or surveys conducted in pure and mixed cropping
adjust or update estimates in light of weather, soil or pest conditions, losses and damages
changes in yield should be explained in relation to factors affecting the crop such as - weather conditions - fertilizer and pesticide - labour supply - pests/diseases - mixtures - crop varieties and their potential yields
should the estimated yield include leaves and shoot weight
5. Annual Production Estimation
scenarios for estimating production should consider yield with or without certain occurring events such as:
- dramatic political events;
- highly positive government interventions;
- exceptional climatic situations;
- high infestation, outbreak, and/or spread of pest/disease.
scenarios could also consider classifications such as:
Thank you for your Attention- poor/very poor crop - normal crop - good/very good crop
