Nematicidal effects of hexane extracts from plants against potato cyst nematodes

  • M. W. Mbiyu University of Nairobi, Department of Plant Science and Crop Protection
  • W. M. Muiru Kenya Agricultural and Livestock Research Organisation -Tigoni
  • J. W. Kimenju Kenya Agricultural and Livestock Research Organisation -Tigon
  • M. W. Nyongesa University of Nairobi, Department of Plant Science and Crop Protection
  • S. Haukeland The Norwegian Institute of Bioeconomy Research
  • S. Haukeland The Norwegian Institute of Bioeconomy Research

Abstract

Potato cyst nematode is an important pest that has devastating effects on production. The effects of hexane extracts from ginger (Zingiber officinale), garlic (Allium
sativum) and Mexican sunflower (Tithonia diversifolia ) at 25, 50, 100 and 150 mg/ml were evaluated against potato cyst nematodes (PCN) under screen house and
field conditions during the long and short rain seasons in 2021. Oxamyl (Vydate) and commercial neem extract (Achook) treatments were included as positive controls
while dH20 was used as the negative control. In the screen house experiment, sprouted tubers of potato cultivar Shangi were planted in 1kg pots containing a steam sterilized potting substrate and arranged in a completely randomized design (CRD). Thirty cysts were placed around the rhizosphere, 14 days after planting. The treatments were soil drenched in each pot 7 days later. The field experiments were conducted in soils with natural infestations of PCN. The study was conducted in a randomized complete block design (RCBD). Field plots measured 3 m × 3 m with spacing of 30 cm × 75 cm. The treatments were drenched into the soil at planting.
Ginger extracts at 150mg/ml had the lowest reproduction index of 0.10 and 0.17 during the short and long rains, respectively. The final cyst (Pf) density showed that
the plant extracts significantly (p ≤ 0.05) reduced the cyst density compared to the control plots. Total PCN population was significantly (p ≤ 0.05) reduced in all the treatments with the reproduction index ranging from 0.50-0.70 in the 2 seasons. Extracts of garlic and Mexican sunflower at 25mg/ml had the highest reproduction index of 0.63 in the short rains while those of Mexican sunflower had the highest reproductive index of 0.76 during the long rains, respectively. All the three botanical extracts significantly increased potato yield compared to the control. Ginger extract, applied at 100mg/ml, increased yield by 112.2 and 80.6% during the short and long rains, respectively. The study, showed that ginger and garlic extract has potential to control PCN infestation in potato. 

Published
2022-05-26
How to Cite
Mbiyu, M. W., Muiru, W. M., Kimenju, J. W., Nyongesa, M. W., Haukeland, S., & Haukeland, S. (2022). Nematicidal effects of hexane extracts from plants against potato cyst nematodes. East African Agricultural and Forestry Journal, 85(1-4), 11. Retrieved from https://www.kalro.org/www.eaafj.or.ke/index.php/path/article/view/503