- Organic Gardening
How to Grow Organic Rice in SRI Method.
Rice is one of our staple foods that feeds the world. Many of us prefer to consume rice harvested from natural cultivation with no use of chemical substances like fertilizers or pesticides. Pesticides and fertilizers, besides burdening farmer due to their high costly prices, those chemical are suspected to be carcinogenics.
Rice grown, raised and treated using biological fertilizer, natural pest controls, and environmentally friendly management also give many benefits for the environment and other micro and macro organisms.
There are some methods in organic rice farmings. One method which has been widely implemented in some countries is SRI (System of Rice Intensification). SRI method was developed firstly in Madagascar island when agriculture suffered unfavorable conditions due to decreasing land productivity, soaring fertilizer prices, and water supply got more limited from time to time.
Since 1999 SRI method was introduced and gained success in its implementation. Many countries in the world have practiced this rice cultivation method including Indonesia, Thailand,The Philippine, India, China, Cambodia, Srilanka, Peru, Cuba, Brazil, Vietnam.
The Advantages of SRI Organic Rice Farming.
SRI method offers some advantages :
- There is no more dependence on chemical pesticides nor fertilizers since organic rice farming only uses organic materials in its treatment and as compost like hays, husk, sawdust, banana leaves, and manure. It creates environmental friendly method in rice cultivation.
- Needs shorter time for seeding, only 7 days instead of 20 days as in conventional farming.
- Need less seedlings, only 7 kg/ha instead of 20 kg/ha as in conventional farming
- One seedling one planting hole, instead of 5 seedlings, and the growing distance is only 30-35 cm which means more rice can be grown at every hectare of field.
- Needs less water. Water can be saved up to 50% compared to the conventional method.
- Integrated naturally pest control with no use of any chemical pesticides.
- Shorter growing time, shorter harvest interval which take 100 days, 15 days shorter than the conventional rice farming.
- Harvest yield rises significantly 10 tons/ha from normally 4.5 tons/ha.
The SRI Procedures.
The following procedures must be followed in order to gain maximum results in organic rice farming using SRI method.
1. Seeding and sowing process.
2. Field treatment process
3. Planting process.
4. Maintenance and care.
5. Composting and Fertilizing process.
6. Pest control.
7. Package, storage, and transportation.
Seeding and Sowing Process.
Seeding process is begun with seed selection. To select good seeds for seeding you can do the following preparation :
a. Prepare a bucket and place some water in it, then put an egg in the water. Slowly add salt into the water and stir carefully. The salted water is ready to be used for rice seed selection when the egg starts to float.
b. Put rice seeds into the salted water and let them there for some seconds. Seeds that sink are selected and considered good to be used in seedling. Separate the good seeds from the float (bad) ones by sieving them.
Wash them with clean water several times then soak them in water for 2 days. Lift them from the water after 2 day-soaking and spread them in flat wooden or bamboo container for incubation step. Incubate the seeds by covering them with damp cloth for 1-2 days until they show small white bud about to grow from endosperms. You need around 5 kgs of good seeds to make seedlings for 1 hectare of rice field.
c. Make a mixture of soil and manure in 1:1 ratio and mix them thoroughly. Prepare somes bamboo or wooden container in 30 cm(l) x 20 cm (W) x 4 cm (H) size, give a plastic or some leave as a layer at the bottom of the container, giving old rice husk to the mixture is recommended as it will help the seedings be lifted easily when they're going to be planted.
d. Spray the media (soil-manure-rice husk mixture) in the bamboo/wooden container with water to make it damp. Spread 200-250 seeds onto the media, cover them with a thin layer of media again with fragments of hays are put as the top cover, then spray with water again so that the surface is also damp.
e. Two leaves will normally grow when the seedings get 7-10 days old and they must be transferred to the rice field.
f. It is recommended to give the seeding light during the night from a 75 w bulb lamp located at 1-2 m away from the seeding. It's also important to keep the seeding areas from animal disturbance/pests. Humidity must be maintained by adding water mixed with compost tea in 30 water :1 compost tea comparison . Commercial compost tea can be bought at agricultural stores or you can prepare it by yourself.
- Compost Tea - Make your own compost tea.
<Garden and domestic refuse can be used to make excellent compost. The compost bin used is important, both to tidiness and to holding the heat, making the difference between a compost heap and a rubbish heap.
2. Field Preparation.
a.Fields that have suffered nutrient drains and have a lot of fertilizer and pesticide residues due to conventional farming the farmers used before, need to be enriched by adding organic substances. To give enrichment to the organic rice fields, they need 7-10 tons of compost per hectare. The compost is made of hays and rice husks.
To make the compost, the hays and rice husks need to be fermented and fermentation can be accelerated with the addition of manure, green leaves, and liquid activator/accelerator in between every layer of hays and rice husks which is around 20 cm in thickness. On top of every layer, accelerator is poured, damp it with water then put another layer of hays and rice husks on the next level and give the same treatment as the first one. Make it 2 to 3 layers and blanket it with a plastic so that the compost pile won't be too wet of rain water nor too dry of sun heat. The fermentation takes place for around 4 weeks until it changes into basic compost.
After the compost is done, we use fifty percent (50%) of it to be spread out evenly on the rice field prior to the plowing step and another 50% will be spread at field-leveling time later.
Having been poured with compost, the rice field area needs to be watered and let it wet for some days before plowing activity. Make sure the water doesn't flow away out of the planting area by choking every outlet and give dykes that can retain the water and also normally function as sidewalks.
Plow the soil up to 60 cm deep to let the healthy roots reach the earth and be able to stand its stem and grains when the rice plants get mature.
b. Make some small water canals along the inside walls of the dykes and one across the field. The canals will serve water supply so that the field can be maintained to have sufficient amount of water. The canals should be around 20 cm in width and at least 30 cm deep. With the canals, water supplies the field be always well aerated and favorable for aerobic microbes to work. Rice is not aquatic plant, so make sure that the water does not excessively flood the rice stems, just make the field moderately wet.
c. Now you have a leveled, wet field and ready to be planted. To be able to plant seedings in good orders, we need to grow them in arrangements that they have the same distance (30 or 35cm) one another. To help us arrange them in such orders we can draw rows of 35cm x 35 cm-squares on the plain field with the help of long canes.
a. Two things that must be fulfilled during planting:
- Water mustn't excessively flood the field during planting. Moderate wet with muddy condition is preferred.
- The seedlings transfer from seedling container to the rice planting field must be done as quickly as possible, mustn't be more than 15 minutes. Too long delay (more than 15 minutes) will lower their growth potential.
b. Plant only one seedling-one planting hole at every corner of the checkers. Dip the seedling stem shallowly, just 0.5-1 cm deep into the mud with the root position is parallel with the field surface so that stem and roots make an "L" like position. We avoid "J" like position caused by deeping the seedling stem not too deep. This dipping technique also distinguishes SRI method from the conventional one.
c. Another planting technique is using Seeding Direct Planting. This technique applies the same seed selections as explained above. The selected seeds are kept for around 2 days until their sprouts grow. The seedings are then planted with planting distance minimum 35 cm. Reserve 2% of the whole seedings for standby seedings and place them near the planting site. Those reserve seedings are to be used to replace the other seedings which do not survive/die.
d. To push the weed growth after planting, more water is given to the field so that it is 1-2 cm above the stem base for 10 days. After 10 days, the water is drained and the field is let to be moderately wet (muddy) again. Compost is spread again in between every 2 rows, and a trench ditch is also made in between every 2 rows of rice.
Care and Treatment.
a. After being planted, the field soil must be kept in moderately wet again. This condition is maintained until 2 weeks before harvest time comes, when we make it completely dry. This is one of advantages SRI method offers that it can save water use up to 50 % than the ordinary method.
b. Replacement must be done in the first 10 days after planting for young rices which do not show perfect growth, damage, or die with new ones taken from reserved seedlings near the field. Replacement should be done carefully to avoid damage on other healthy rice stems and like the planting method has been explained above, one hole-one seedling and only need to be dipped shallowly.
c. Weeding is very important in maintaining production to be optimal. Production may go down significantly if weeding is not properly done. Weeding must be executed regularly in every two weeks and the first weeding has to be conducted at the first 10 day after planting. Besides picking off the weeds, soil aeration also becomes the objective of weedings through soil inversion. The picked weeds can be submerged in the soil to make it as compost.
To do the weeding plus soil inversion you can use tools called weeder and harrow. These tool are used to weed as well as inverting surface soil.
Long uses of chemical fertilizer and pesticides uncontrollably have ruined soil structure and soil microorganisms which play important roles in creating fertile soil. This deteriorating condition is shown with decreasing field productivity, repeated attacks of of rice pests and parasites intensively and extensively in short time period. Rice fields suffering such condition, therefore need rehabilitation to heal it. The land rehabilitation needs pretty amount of 8-10 tons/ha of organic materials and around 3 tons/ha of organic compost fertilizer. Farmers can prepare their own organic materials from previous planting seasons like hays. Liquid organic compost can be added to rehabilitation to make it more effective.
Pest and Desease Control.
SRI is implemented to give farmers knowledge about environmental friendly rice farming. This technique is meant to increase rice production through the uses of organic materials in its implementation while the life of useful microorganisms are not disrupted.
Farmers in West Java have admitted the benefits of SRI which give them much better rice harvests compared to the method they used before. Besides rice grains yielded by every rice stem has increased, natural method also suppresses the losses caused by parasites and diseases because their growths are always simultaneously followed by the presence or their natural predators.
Irrigation technique in SRI with the minimum use of water also brings positive effect that Channeled Apple Snail (Pomacea canaliculata) attack as one of rice pests can effectively be hindered.
Common Rice Pests and Their Biological Treatments.
Mouse is the most alarming pest for rice farmers because of its fast attacks and causes extensive damage. Fortunately that rice planted with SRI method has bigger and harder stems so that it's not favorable as mouse food.
Mouse hates strong smells produced by certain plants and fruits like jengkol (Archidendron pauciflorum) and the extra bitter taste of Brotowali (Tinospora tuberculata). Based on this fact, farmers make extracts of those plants' fruit (jengkol), and stems and leaves (brotowali). They spray their rice fields with those natural pesticides to repel mouse. A wise effort in expelling mouse without hurting environment.
In Cambodia farmers use bitter bush (Chromolaena odorata) over the field surface after planting. This practice makes some benefits like giving more moisture to rice field, become compost and help inhibit weed growth and repel insect pest. While in India farmers use Ceylon satinwood (Chloroxylon sp) for pest control in organic rice cultivation.
Birds and dragon flies also cause pain in the neck to farmers. Besides the tempting rice grains (for birds), birds and dragon flies also love locations with twinning or upright objects to perch. Based on this behavior, farmers put series of bamboo stands in and around the rice field to give those pests perching places.
Pest control can also be done using biological insecticide like Bacillus thuringiensis and also pyrethrum, natural insecticide made from dried flower of Chrysanthemum cinerariifolium and Chrysanthemum coccineum.
Other biologgical insecticides can be made from extracts of tobacco leaves, Mindi (Melia azedarach), Garlic (Allium sativum) while for fungicide we can use the extract of turmeric (Curcuma domestica).
Harvest the rice grains must be done mechanically and manually. Should the rice grains be washed, they must be dried at open air before being package. Wet, dirty grains mustn't be put in plastic package to avoid putrefaction.
Application of chemical fungicide for any parasites and fungal prevention is strictly forbidden.
Storage and transportation.
Organic rice must kept away from chemical substances and other materials, including non organic rice, that may contaminate it during its storage and transportation. The transport must be closed and air conditioned, clean, free from chemical materials and other non organic food stuffs. The rice should be delivered shortly after harvest if possible to minimize quality degradation and storage cost.