Diversity of cassava (Manihot esculenta Crantz) cultivars and its management in the department of Bouenza in the Republic of Congo

2012 ◽  
Vol 59 (8) ◽  
pp. 1789-1803 ◽  
Author(s):  
G. R. Kombo ◽  
A. Dansi ◽  
L. Y. Loko ◽  
G. C. Orkwor ◽  
R. Vodouhè ◽  
...  
2020 ◽  
Vol 14 (7) ◽  
pp. 2517-2527
Author(s):  
Valentin Dibangou ◽  
Mireille Belle Mbou ◽  
Nazaire Loubaki Ntolo ◽  
Grâce Nianga-Bikouta

Dès l’année 1970, une baisse de production en tubercules de manioc de l’espèce Manihot esculenta Crantz (Euphorbiacée) a été constatée en Afrique. L’un des principaux ravageurs de cette plante est la cochenille farineuse du manioc. Au Congo, la lutte contre celui-ci s’est organisée dès 1982 par l’introduction d’un parasitoïde hyménoptère, Epidinocarcis lopezi. Mais cet insecte auxiliaire s’est très vite retrouvé à son tour la proie d’hyperparasites qui freinent ainsi son expansion et limitent son efficacité. La présente étude fait un inventaire des entomophages de la cochenille du manioc Phenacoccus manihoti. Elle s’est déroulée dans trois sites retenus dans la ville de Brazzaville : Kombé, jardin d’essai et Lycée Savorgnan de Brazza (LSB). La récolte des momies a été effectuée sur des feuilles infestées, les arthropodes ayant émergé ont été collectés et identifiés, les taux d’émergence et d’hyperparasitisme ont été déterminés. Les résultats obtenus montrent un taux d’hyperparasitisme élevé (60 et 66,66%) et une faible abondance d’E. lopezi comparé aux hyperparasites (22 hyperparasites pour 13 parasitoïdes). Un autre parasitoïde Acerophagus coccois Smith non encore décrit jusqu’ici au Congo a été découvert. Il pourrait avoir été introduit accidentellement avec les boutures importées et expérimentées dans le but d’améliorer les performances du manioc.Mots clés : Lutte biologique, Auxiliaire, Entomocénose, Momie, Brazzaville, Congo. English Title: Rapid inventory of the main entomophagous species of the cassava mealybug Phenacoccus manihoti (Homoptera: Pseudococcidae) in the Republic of Congo As early as 1970, a decrease in the production of cassava tubers of the species Manihot esculenta Crantz (Euphorbiaceae) was observed in Africa. One of the main pests of this plant is the cassava mealybug. In the Congo, the fight against it was organized in 1982 with the introduction of a hymenoptera parasitoid, Epidinocarcis lopezi. But this auxiliary insect very quickly found itself the prey of hyperparasites, which thus slowed down its expansion and limited effectiveness. The present study makes an inventory of the entomophages of the cassava mealybug Phenacoccus manihoti. It took place in three selected sites in the city of Brazzaville: Kombé, test garden and Lycée Savorgnan de Brazza (LSB). The mummies were harvested from infested leaves, emerging arthropods were collected and identified, rates of emergence and hyperparasitism were determined. The results obtained reached a high rate of hyperparasitism (60 and 66.66%) and a low abundance of E. lopezi compared to hyperparasites (22 hyperparasites for 13 parasitoids). Another parasitoid Acerophagus coccois Smith not yet described in Congo has been discovered. It could have been created accidentally with the imported cuttings and tested in corn to improve cassava performance.Keywords: Biological pest control, Auxiliary, Entomocenosis, mummy, Brazzaville, Congo.


Waterlines ◽  
2005 ◽  
Vol 23 (3) ◽  
pp. 22-24 ◽  
Author(s):  
Marco Visser

2017 ◽  
Vol 13 (1) ◽  
Author(s):  
Izabel Aparecida Soares ◽  
Mauro Sérgio Téo ◽  
Carlise DEBASTIANI ◽  
Suzymeire BARONI ◽  
Vanessa Silva RETUCI

O trabalho teve por objetivo verificar diferenças entre rendimento do concentrado proteico e proteína bruta da folha da mandioca (Manihot esculenta Crantz), obtidos a partir de três variedades comerciais: branca, cascuda e vermelha. As manivas foram plantadas seguindo o delineamento experimental inteiramente casualizado com três repetições. Nas comparações entre as variedades, considerou coletas escalonadas pós-plantio, realizadas aos 12, 14 e 16 meses. O concentrado proteico foi obtido a partir da farinha das folhas inteiras e submetido ao método de termo - coagulação ácido e a proteína bruta pelo método padrão AOAC. Os dados foram submetidos a análise de variância e comparados pelo teste de Tukey - 5% de probabilidade. Os resultados não indicaram diferença significativa entre as médias obtidas para rendimento de concentrado proteico. Para a variável porcentagem de proteína bruta a variedade Branca foi a que apresentou maior valor, com média de 46,25%, seguida pela Cascuda e Vermelha, 44,52% e 37,30%, sucessivamente. Conclui-se que outros estudos devem avaliar condições que possam influenciar no teor de proteína foliar, como clima e solo, e, avaliar os níveis de ácido cianídrico de cada variedade, indicando qual das três é a melhor para a extração do concentrado proteico das folhas. Palavras chaves: Manihot esculenta Crantz, variedades comerciais, concentrado proteico, proteína bruta. ABSTRACT: The study aimed to assess the differences between income protein concentrate, crude protein of cassava leaf (Manihot esculenta Crantz), obtained from three commercial varieties: white, red and cascuda. The cuttings were planted following the completely randomized design with three replications. Comparisons between the varieties considered after planting staggered collections, held on 12, 14 and 16 months. The protein concentrate was obtained from flour of whole sheets and subjected to the term method - acid coagulation and crude protein by AOAC standard method. The data were submitted to ANOVA and Tukey test - 5% probability. The results indicated no significant difference between the mean values obtained for protein concentrate income. For the variable percentage of crude protein White variety showed the highest, with an average of 46.25%, followed by cascuda and Red, 44.52% and 37.30%, successively. We conclude that further studies should evaluate conditions that may affect the leaf protein content, such as climate and soil, and evaluate the hydrocyanic acid levels of each variety, indicating which of the three is the best for the extraction of protein concentrate from leaves Key words: Manihot esculenta Crantz, commercial varieties, protein concentrate, crude protein.


2002 ◽  
Vol 6 (25) ◽  
Author(s):  
A C de Benoist

On 12 June 2002, the Ministry of Health of the Republic of Congo reported six suspected cases, including five deaths, of acute haemorrhagic fever syndrome in Mbomo district, near the Gabonese border (1). The first cases occurred in a group of people who had been working in a gold mining camp in a forest south of Oloba. It seems that they may have been exposed to the same source, a chimpanzee found dead in the forest.


Author(s):  
Barros Sâmela Leal ◽  
Santos Newton Carlos ◽  
Araújo Thaís Jaciane ◽  
Melo Mylena Olga Pessoa ◽  
Nascimento Amanda Priscila Silva

Author(s):  
Brochado Maura Gabriela da Silva ◽  
Botelho Matheus Gabriel Lopes ◽  
Souza Camila Eduarda Sousa de ◽  
Nunes Mariana Lameira ◽  
Ferreira Leonardo Elias

2018 ◽  
Vol 1 (1) ◽  
pp. 10-16
Author(s):  
Fadhillah Laila ◽  
Budi Waluyo ◽  
Agung Kurniawan

Indonesia memiliki kekayaan plasma nutfah ubi kayu yang tersebar di seluruh wilayah Indonesia. Ubi kayu mengandung karbohidrat tinggi dan berperan dalam diversifikasi pangan. Tujuan dari penelitian ini adalah menyeleksi 80 varietas ubi kayu budidaya lokal asal berbagai wilayah di Indonesia yang berpotensi hasil tinggi. Penelitian ini menggunakan 80 aksesi ubi kayu dari seluruh pulau-pulau besar di Indonesia yang disusun dalam rancangan Augmented dengan 3 tanaman kontrol per baris. Penelitian dilakukan dari Juli 2013-November 2014. Hasil penelitian menunjukkan bahwa keragaman genetik dan fenotipik yang luas pada ubi kayu asal Indonesia berdasarkan karakter umbi. Potensi genetik berdasarkan karakter hasil dan komponen hasil terkategorikan tinggi dengan nilai heritabilitas 0,59-0,75. Uji lanjut LSI (Least Significant Increase) menyeleksi aksesi yang memiliki daya hasil tinggi pada karakter umbi diantaranya karakter jumlah ubi/tanaman pada aksesi 563, 570, dan 599. Karakter bobot ubi/tanaman pada aksesi 507,563, 598, dan 541. Karakter bobot/ubi pada aksesi aksesi 534,528 dan 541. Karakter bobot ubi/plot pada aksesi 629. Karakter potensi hasil pada aksesi 629. Hal ini dapat memberikan informasi mengenai diversitas genetik aksesi-aksesi ubi kayu lokal Indonesia sehingga dapat dievaluasi untuk didapatkan hasil tinggi ubi kayu untuk diversifikasi pangan.


Sign in / Sign up

Export Citation Format

Share Document