Rice is one of the most important cereal crops in Kenya coming third after maize and wheat. It forms a very important diet for a majority of families in Kenya and is the source of livelihood in the Greater Mwea region. The demand for rice in Kenya has increased dramatically over the last few years while production has remained low.
To produce healthy seedlings, the following should be done:-
Seed selection. Select plump and healthy seeds.
Seed pretreatment. This is practiced to ensure better germination of seeds and better growth of
seedlings. It involves:
- Seed disinfection. Hot water treatment is effective in destroying the nematodes, which cause the white tip disease.
- Seed soaking. In order to supply the required moisture for germination, shorten germination period and reduce seed rotting.
- Pre-sprouting. The seeds are drained and covered with grass for 24 to 48 hours. This ensures uniform seed germination, avoids over sprouting and allows air circulation for germination.
Under irrigation: Land preparation is carried out by flooding the fields to a depth of 10 cm and then cultivating by use of tractor. The land should be tilled and immediately flooded at least 15 days before transplanting or direct sowing. Under rain-fed situation: Land should be ploughed twice and harrowed once.
Planting should be before the onset of long rains for rain fed rice. It is important to transplant from the nursery as soon as the seedlings are big enough. Seedlings are said to be ready for transplanting after a period of between 3 to 4 weeks depending on daylight, temperatures and the variety.
Seedlings are spaced according to the tillering ability of a variety. Two to three seedlings for low tillering varieties. One to two seedlings per hill are more suitable for good rooting and tillering. Higher seedling rates increase competition for the available nutrients, hence should be discouraged
For rain fed rice carry out weeding three times, first weeding done 2-3 weeks after germination, second prior to topdressing and third one before panicle set. Use herbicides such as Satonil or Karachi.
White rice borer: Practice good field hygiene, plant resistant varieties, use systemic insecticides such as confidor.
Birds: Quelea quelea bird, use bird scaring devices, monitor regularly for breeding sites, report to agricultural office for assistance.
Rice stem borer:Plant resistant varieties, practice good field hygiene, use systemic insecticides eg confidor.
Stalk eyed fly: Use systemic insecticides eg confidor.
Rice leaf hoppers: Use insecticides such as endosulfan.
NB: Chemical control measure should be adopted when pest damage is severe!
Blast: Plant resistant varieties, proper plant spacing, avoid excessive nitrogen application in the field, practice good field hygiene.
Sheath blight: Plant resistant varieties, use suitable broad-based fungicide eg ridomil.
Rice yellow mottle virus: Plant resistant varieties, practice good field hygiene, control insect vectors.
Sheath rot: Plant resistant varieties, use fungicides eg ridomil.
Rice production is set to increase, with the use of a new method of growing paddy that is already boosting yields, reducing water usage and bolstering profits at the Mwea Tebere Irrigation Scheme in Kirinyaga County, the main rice farming region.
The Water Saving Rice Culture (WSRC) consists of five technologies that include the use of healthy seedlings, hand leveling, line planting, improved weeding and intermittent irrigation. Water shortage is one of the biggest challenges in Mwea.
Manual leveling after rotavation or animal traction in the field is critical at the land preparation stage. It ensures uniform water distribution to all seedlings.
It also results in successful transplanting and easy water management.
The WSRC also recommends use of healthy seedlings. The seeds are pre-germinated by soaking in water for 24 hours followed by incubation for another 48 hours to attain higher even germination.“Pre-germinated seeds are then sown at 100g per square metre.
In the conventional method, seeds are sown at a high rate of up to 300g per square metre, which leads to elongated and weaker seedlings, with a higher incidence of disease. Transplanting the seedlings should be done at three weeks, as this leads to higher yields.
Another departure from conventional rice growing is line planting. With a spacing of 30cm by 15cm, an appropriate plant population is obtained unlike in random planting.
Gapping should be done to maintain optimum population to maximize yields.
Push-weeders should be used in weed control between the rows, according to experts. Two people can work on an acre of land using the weeder.
This is the revolutionary part of WSRC. The ‘Alternate Wetting and Drying (AWD)’ involves three days of flooding up to 2cm in depth, followed by four days of draining or drying. The practice starts 10 days after transplanting and repeated for the next month. Leveling is a key factor of intermittent irrigation because the method requires the water to spread evenly.
Drained fields under this watering regime enable oxygen to get into the soil and saves water usage by more than 20 per cent.