Management of Rice Blast Using Silicon Sourced From Rice By-Products And Chemical Sources

  • C.W. Muriithi
  • E. N. Mungai
  • A.W. Kihurani
  • L.S. Nafuma
  • S. Amboga


Rice (Oryza sativa) is an important crop in Kenya. It ranks third after wheat and maize contributing to over 20% of the total calorie intake BY humans. The varieties ITA 330, IR2793-80-1, BW 196 and basmati/pishori 370 are commonly grown in Kenya. Basmati 370 is most preferred varieties for commercialization because it commands premium prices and occupies over 80% of the land.  However, it is susceptible to rice blast (Pyricularia oryzae) which is one of the most important diseases of rice causing an economic loss of 70-80%, thereby threatening Kenya’s food security.  The objective of this study was to evaluate different rice blast management approaches using different sources of silicon compared to chemical control.  The experiment was carried out in Mwea Irrigation Scheme in Kirinyaga district.  It was laid out in a Completely Randomized Design (CRD) with six treatments: Calcium silicate (1000 Kg/ha), Potassium silicate (1 l/ha) and rice by-products (rice straw, 0.7 ton husk ash equivalent to 2 tons before burning and 0.6 ton straw ash equivalent to 2 tons before burning). Basal fertilisers were applied at 30 Kg K2O/ha, 58 kg P2O5 /ha and Nitrogen (N) was applied as top dressing (80 kg N) in two splits. Inoculum of Pyricularia oryzae (4 × 105 conidia/ ml) was used to infect the rice plants and panicle blast infection assessed using a scale of 0 - 9, the IRRI standard.  Treatments with calcium silicate, ash husk and potassium silicate were not significantly different on yield and in control of rice blast in that they all recorded higher yields but on the other hand they also recorded the least rice blast ratings.  These results show that rice by-products can successfully be utilized in the management of rice blast.

How to Cite
Muriithi, C., Mungai, E. N., Kihurani, A., Nafuma, L., & Amboga, S. (2011). Management of Rice Blast Using Silicon Sourced From Rice By-Products And Chemical Sources. East African Agricultural and Forestry Journal, 76(1&2). Retrieved from