Diversity and agronomic impact of rice stem borer at Nkolbisson, Yaoundé-Cameroon (Central Africa)
International Journal of Agronomy and Agricultural Research (IJAAR), Vol. 6 (No. 4):
p. 181-189 (April 2015)Abstract
Today, rice has become one of the most consumed cereals in Africa in general and Cameroon in particular. The low domestic
production imposes a strong import that accentuates the country's trade imbalance. To reduce this issue of external
dependency, the national government is encouraging domestic production. However, producer’s efforts are inhibited by various
constraints among which the pest attacks in general and in particular the stem borers. Data collection was based on sampling
and incubation of white rice panicles in an experimental plots set up at Nkolbisson, Yaoundé. The susceptibility of rice varieties to different pest species was evaluated by comparing the frequency of pest species on their infested panicles. Among the NERICA rice lines, NERICA 3 had the greatest percentage of attacks panicles that was 41.96 % while NERICA 9 and 13 had the
less percentage of attacks panicles that was 14.29 % for both of them. A total of three pest species were identified from the
panicles incubated, Orseolia oryzivora, Chilo zacconius and Diopsis apicalis, O. oryzivora being the most frequent. NERICA 3
with 41.96% of incubated panicles appears to be the most susceptible variety, while the Japanese’s Akitakomachi and
Fukuhibiki showed no attack. These results are discussed in relation to the total sugar content and polyphenol in different rice varieties studied.