Page 84 - Agriculture Form Two

Agriculture for Secondary Schools

Nutrient management
Organic and inorganic fertilisers are used to improve yield in round potato
production. Their application rates will vary depending on soil test results specific
to an area. Organic fertilisers include farm yards and compost manures, which
FOR ONLINE READING ONLY
are slow-release organic fertilisers that can be used. Compost is a decomposed
mixture of organic residues (manure, straw, ashes, kitchen wastes). Fresh manure
can burn seed round potatoes when it comes into contact with them or if placed
too close. Various types of industrial fertilisers are used at different stages of
plant growth. For instance, diammonium phosphate (DAP) is applied during the
crop planting. At the same time, fertilisers like calcium ammonium nitrate (CAN)
and urea are used to top-dress later in the growth cycle. When growing round
potatoes, it is recommended to apply DAP fertiliser as advised by an agricultural
expert at a rate of 250-375 kg per hectare. Apply fertiliser per planting hole on
the furrow and cover it lightly before planting tubers to prevent fertiliser-seed
contact that may burn seer potatoes. Avoid using excess nitrogen, as it promotes
vegetative growth at the expense of tuber formation.

Alternatively, use either DAP or a combination of Triple Superphosphate
(TSP) with Calcium Ammonium Nitrate (CAN) per hectare in the furrows
during planting as per recommendation after testing the soil. If the soil is low
in potassium, farmers should use Muriate of Potash. Root crops require more
Potassium (K) than Nitrogen (N) and Phosphorus (P), so it’s essential to apply
the recommended amount of Potassium per hectare. Another suitable fertiliser is
NPK. However, the soil fertility status should determine the type and amount of
fertiliser to be used. You should consult an agricultural expert in your area for the
appropriate variety and fertiliser rate.

Activity 5.6

1. Through farm visits, internet searches, library, and market surveys:
(a) Identify different types of organic and inorganic fertilisers that are
recommended for round potato production;

(b) Estimate the amount and the right time of application for each fertiliser
to potato plants;
2. Under the guidance of your teacher, choose and apply the right fertiliser in
your plot accordingly; and,
3. Keep on observing and recording the development of the crop plants.

76 Student’s Book Form Two

04/10/2024 18:07
Agriculture form 2.indd 76 04/10/2024 18:07
Agriculture form 2.indd 76