Open Agriculture. 2017; 2: 83-90 and measured parameters, was most appreciated and was the farmers' first choice, followed by varieties TIB-440060 and 'Bela bela'. Keywords:Orange-fleshed sweetpotato, on-farm Demonstration, participatory varietal selection, sweetpotato IntroductionSweetpotato is cultivated in all the regions of Côte d'Ivoire for consumption and also as a source of income. It is a dicotyledonous plant called Ipomoea batatas (Lam.) that belongs to the family Convolvulaceae, and a tuberous root crop important for food security (Ermias et al. 2013). Globally it is among the important food crops in the world, after wheat, rice, maize, Irish potato, and barley and it ranks second following Irish potato in the world's root and tuber crops production and third after Irish potato and cassava in consumption in several parts of tropical Africa (Teshome et al. 2012). Sweetpotato is also a good source of calcium, ascorbic acid (vitamin C) and beta carotene (provitamin A). Varieties with orange flesh contain particularly high levels of beta carotene which is converted to vitamin A in the human body (Sakamoto et al. 1987); while there is moderate amount of beta carotene in yellow-fleshed and none in white-fleshed varieties (ACIAR, 2010 andStathers et al. 2013). Vitamin A is involved in building the body's immune system to defend against disease and blindness (WHO, 2014). According to the World Health Organization (WHO), vitamin A deficiency (VAD), which is associated with low consumption of products rich in vitamin A is common and is a serious health problem in many developing countries (including Côte d'Ivoire). According to FAO (2009) (OFSP) is hampered by the lack of genetic resources and planting material. To evaluate and release OFSP varieties, on-farm demonstration tests were conducted with women farmer groups in Bondoukou, Nassian, Korhogo and Bondiali in the north and northeast Côte d'Ivoire. Six varieties-'Kabode', 'Kakamega7' ('Irene'), 'Tacha', 'Bela Bela', 'Vita' and TIB-440060-were evaluated in comparison with locally grown varieties. The on-farm demonstration was laid out in a randomised complete block design with replicated three times per location. Assessments were made on yield, disease and pests; and consumer preference on attractiveness of skin color and flesh of the root (fresh and boiled), taste, texture and starchiness. Results showed that introduced varieties have generally recorded higher yields than the local varieties: Yields of about 25 t/ha have been recorded on the sites. The best average yield of about 15 t/ha, was recorded for TIB-440060 and 'Irene' varieties. Farmers' acceptance of OFSP varieties based on the attraction of their color, the dry matter content and taste was more than 90%. At the end of the sensory tests, 'Irene', which achieved the best compromise between all observed

Yam (Dioscorea spp.) is the second most important root and tuber crop after cassava and a major staple food in sub-Saharan Africa, where it plays a vital role in food security for more than 60 million people. Five West African countries (Benin, Côte d'Ivoire [Ivory Coast], Ghana,Nigeria, and Togo) account for more than 95% of the worldwide yam production (FAOSTAT, 2020). In Côte d'Ivoire, yam is the leading staple crop with more than 7.2 million tonnes produced in 2018, with D. rotundata representing 75% of yam trade in the

Yam is the first food crop in Côte d'Ivoire. It is being cultivated under a traditional technique system with low output. Detailed profiling of the current practices and opportunities for improvement is essential to increase the

Collection and characterisation of plant materials is a crucial step in crop improvement programmes. The objective of this study was to characterise a sweet potato (Ipomoea batatas [L.] Lam.) collection from the Centre National de Recherche Agronomique (CNRA) in Côte d'Ivoire, based on morphological characters, and to elucidate the relationships among them. The experiment was carried out in a Fisher design with two replications. The descriptive analyses revealed a substantial phenotypic variation within the collection. The multiple correspondence analysis showed that 15 characters out of 27 were the most discriminant to explain the variation. Furthermore, significant relationships were observed between phenotypic traits related to leaves, stems and storage roots. The hierarchical classification placed accessions into three genetic groups regardless of their geographical origin and revealed the existence of duplicate accessions. The results obtained could be used for the selection, improvement and sustainable management of sweet potato genetic resources.

The Black Leaf Streak Disease (BLSD) is one of main parasitic constraints of the agro-industrial plantations of banana in the world. Caused by a fungus ascomycete (Mycosphaerella fijiensis Morelet), the losses of yield are up to 50 %, without of resistant cultivars and effective management. This study relative to the level of the disease has been conducted in 12 industrial plantation in 6 production area: Aboisso, GrandBassam, Dabou, Agboville, Azaguié and Tiassalé; for a total surface of 2576 ha. The observations concerned the ranks of Youngest Leaf Spotted (YLS), of the Youngest Leaf Necrosed (YLN), the Number of Standing Leaves (NSL) and the gap between the Youngest Leaf Spotted and the Number of Standing Leaves. The results showed that chronic re-infestation of industrial plantation during the last five years, except CDBCI Tiassalé-Songon in 2011 European Scientific Journal January 2016 edition vol.12, No.3 ISSN: 1857 -7881 (Print) e -ISSN 1857 38 and 2012. An acceptable level of re-infestation was observed in 2012 on other plantations, with the rank of YLS greater than or equal to 3, except BATIA Tiassalé and CDBCI Azaguié. The internal inoculum pressure (YLS) varied a lot from one plantation to another and from one year to another. Except plantation SBMK Aboisso and BATIA Tiassalé, other plantations had at least one value of the rank of the top YLS or equal to 8, during the study indicating a relatively low severity of the BLSD. RésuméLa maladie des raies noires (MRN) est une des principales contraintes parasitaires des plantations agro-industrielles de banane dessert dans le monde. Causée par un champignon ascomycète (Mycosphaerella fijiensis Morelet), les pertes de rendement dues à cette maladie foliaire peuvent dépasser 50 %, en absence de cultivars résistants et de lutte efficace. Cette étude, portant sur le niveau de la maladie, a été menée dans 12 plantations industrielles réparties en 6 bassins de production : Aboisso, Grand-Bassam, Dabou, Agboville, Azaguié et Tiassalé ; pour superficie totale 2576 ha. Les observations ont porté sur les rangs de plus jeune feuille touchée (PJFT), de la plus jeune feuille nécrosée (PJFN), le nombre de feuilles érigées (NFE), l'écart entre la plus jeune feuille touchée ( IntroductionLa maladie des raies noires (MRN) due au champignon Ascomycète (Mycosphaerella fijiensis Morelet) est la principale contrainte fongique affectant les bananiers après la reconversion variétale liée à la maladie de Panama (Lassoudière, 2012). En effet l'industrie bananière n'a dû son salut qu'au remplacement de la variété Gros Michel (sensible à l'agent causal de la maladie de Panama Fusarium oxysporum f. sp. cubense) par des variétés du groupe sinensis (Lassoudière, 2012). Initialement connue sous une forme dite jaune, relativement moins agressive (M. musicola Leach), la maladie des raies noires possède un spectre d'hôtes plus large puisqu'elle attaque avec succès les cultivars du groupe plantain, lesquels sont résistants à M. musicola (Fullerton, 1994). Elle est responsable de l...

Yam is an important food crop in Côte d'Ivoire. Nevertheless, its production is facing many constraints including the inability to distinguish cultivated varieties from one another. Thus, different varieties and species are designated by the same names from one region to the other and vice versa, the same varieties are called differently. The absence of major descriptors, which are easy to use is the main cause of this confusion. The objective of this study is to propose agro-morphological descriptors easy to identify, for a better determination of yam varieties of D. alata. A total of 91 accessions of yam of D. alata species were used. These accessions were observed using morphological parameter. Eight simple agro-morphological descriptors which are easy to describe were identified as major dichotomous keys for the determination of the D. alata species. These characters have been selected based on the discrimination they permit to operate. Using them, four varietal groups were formed: Pyramid, Douoblé, Brazo and Bêtê-Bêtê.

No abstract

Black Sigatoka, caused by Mycosphaerella fijiensis Morelet (Pseudocercospora fijiensis [Morelet] Deighton), is one of the most devastating diseases of banana. In commercial banana cropping systems, Black Sigatoka is mainly managed by fungicides. The emergence of resistant strains of M. fijiensis to commonly used fungicides has necessitated an evaluation of their efficacy on untreated (wild) populations. Our study on the effectiveness of the main fungicide molecules used in Côte d’Ivoire in the control of black leaf streak disease (BLSD) was conducted to develop new sustainable control strategies. The efficacy test of the different fungicides on M. fijiensis strains made it possible to classify the fungicides according to their capacity to reduce and delay the appearance of the first symptoms of the disease. trifloxystrobin (strobilurin) was most effective in controlling black stripe disease, followed by propiconazole, mancozeb and methyl thiophanate. However, the best result was obtained with mancozeb about the appearance of the first symptoms of the disease.