Effect of aphids and virus diseases on yield of seed potatoes in Kenya
Date
2003Author
MACHANGI, J
OLUBAYO, F
NDERITU, J
NJERU, R
EL-BEDEWY, R
OBUDHO, E
Type
PresentationLanguage
enMetadata
Show full item recordAbstract
Experiments were conducted at 2 sites to determine the relationship between aphid populations, virus incidence
and yields on 4 potato varieties (Solanum tuberosome). These varieties were planted at Tigoni and Kabete during short
rains, October 2001 – January, 2002) and long rains, (March to July, 2002). The experimental design was completly
randomised block design with 3 replicates. Sampling was done every 2 weeks from crop emergence to maturity. Aphid
populations were assessed based on a random collection of 15 leaf samples per plot and virus incidence was assessed
basing on number of plants infested per plot. At harvest, season, yields were measured for each treatment and compared
with the average scores of aphids and virus incidence over the season. A regression analysis of this data revealed that
there was a significant decrease in yields with increase in virus incidence at both sites (P<0.05). Similarlly, there was a
significant decrease in yield with increase in aphid populations at the Kabete site but not at the Tigoni site. Although no
significant relationship between the aphid populations and virus incidence was observed at either Tigoni or Kabete, as
the populations of aphids increased, the virus incidence also increased. It is therefore, necessary to control aphid
populations to reduce virus spread in order to achieve optimal yields of seed and ware potato in Kenya
Citation
MACHANGI, J., OLUBAYO, F., NDERITU, J., NJERU, R., EL-BEDEWY, R., & OBUDHO, E. (2003). Effect of aphids and virus diseases on yield of seed potatoes in Kenya. In African Crop Science Conference Proceedings (Vol. 6, pp. 220-223).Publisher
University of Nairobi. Department of Crop protection