By Samuel Nzioka
Farmers within Laikipia west sub-county are worried of new
maize disease that is destroying their crop. Maize Lethal Necrosis disease
has affected maize crop in many farms leaving farmers panicking for their
produce. The disease has been declared as ‘New threat to Maize production’. Being a new disease in Laikipia County,
farmers lack information on how to tackle its spread.
The disease
According to Ministry of Agriculture, Livestock and
Fisheries State department of Agriculture, Maize Lethal Necrosis Disease (MLND)
results from co-infection of two viruses; Maize
chlorotic Mottle Virus and Sugarcane
mosaic Virus. The disease is reported to be spread by insect vectors such
as Maize thrips, Maize leaf hoppers, leaf beetles and aphids. In Kenya, the
disease was first reported in Bomet County in September 2011.
Commonly grown maize varieties are susceptible to the
disease. Losses associate with the disease ranges from 30 to 100% depending on
crop growth stage when the disease attacks.
Symptoms and effects
of MLND
- Bright yellowing starting with the upper young leaves
- Stunted growth with shortened internodes
- Death of inner parts of the plant leading to premature plant death
 |
| Infected crop in Matwiku, Laikipia west sub-county |
- Poor pollen production and sterility of plants
- Comb husks appear mature (brown color) while the grains inside are still milky and the rest of the plant is green
- Partial grain or no filling capacity, the formed grains also become moldy with brown discoloration
- At late stages of plant growth, there is a lot of fugal growth on stems and combs
- Death of entire crop gives a blighted appearance to the maize field. The disease can be seen from as early as two weeks after emergence on wards
What to do about it
a)
When planting maize;
·
Use certified seeds approved by relevant
authority (KEPHIS)
·
Use manure and include basal and topdressing
fertilizers
·
Plant at onset of rains, undertake timely
weeding and field sanitation
·
Planting tolerant or resistant maize varieties
would be the longterm and sustainable solution
b)
Do not grow maize in consecutive seasons
c)
Practice crop rotation and diversify crop
choices with alternatives like irish potato, sweet potato, beans and vegetables
d)
Practice regular scouting for insect vectors and
early appearance of MLND
e)
At early stages of disease onset, rogue out
infected plants. This material can be used to feed livestock
f)
Grains and cobs that are rotten are not supposed
to be fed to humans or animals but rather be destroyed by burning
g)
Do not move green maize materials from infected
regions to disease free areas within and outside the country to minimize spread
of MLN disease.
There is a need to have farmers trained on intervention
measures so as to have them prepared to tackle the disease whenever it strikes
and to avert crop losses cause by the disease.
