This report is made based upon the investigations of the castor cultivation in Thailand and the analytical experiments of materials taken during 20 th, September, 1961 and Junuary, 1962 and their summaries are as follows;
1. It is desirable to make the plan of increasing production because the demand of the castor seed oil in the world seems to increase in days to come.
2. It is desirable to take up the castor cultivation for the economy of farmers because it seems to have no disadvantage compared with the other crops which are cultivated in the same period.
3. It can be developed advantageously in the international market because the cost of the castor seed produced in Thailand is cheaper than the other countries and conditions of the productions are not bad
4. It is desirable to form the main production area in the following where the increased plan can be made. As the main production area, Nakornrajsima area as the center of the Northeastern part, and areas of Sarabusi, Supanburi, Lopburi and Chainat, and Sukhothai and Kanchanaburi districts of the Central plain are the areas for forming the main production areas.
5. By different period of production, there is much difference in moisture content, oil content and acid value in the castor seed produced in Thailand and there are many cases of the qualitative change during exporting. So it is desirable to improve positively to correct above by adopting non-dehiscence varieties, moving the cultivation period, adopting of the topping method, excluding the immatured seed, etc.
6. At present, the adoptation of Kao Dam species is desirable but it seems much desirable to breed a several varieties considering ecological character and also it is desirable to find out the most adequate variety of each district by a comparative study.
7. Adoptation of F₁ castor hybrids at present seems to be difficult but if the experiment equipment and the original seed farm are completely established, the increase porduction by F₁ castor hybrids can be expected in the future.
8. It is not desirable to adopt the American varieties when many conditions of Thaliand are considered. It is desirable to adopt the excellent varieties which are breeded from the indigenous varieties.
9. It is necessary to guide the topping method positively for decreasing the cost of harveslrng by increasing production and making the harvest easy.
10. It is desirable to encourage the cultivation of the intercropping for distributing the danger because of exporting crop and making the increase profit per hectare.
11. It is desirable to cultivate as the annual crop because the second year culture up decreases the yield, intercropping becomes difficulty and much harvesting expenses are required because of higher plant height.
12. The chemical fertilizer can be considered to supplement the insufficient supply of organic matters by intercropping of the leguminous crop.
13. It must be avoided to harvest the immatured capsule.
14. For control of the injurious insects, the insecticide such as Denapon can be used, but at the other hand, it is desirable to study the effective use of the natural enemy.
15. Collecting and inspecting agencies by the nation should be established and it is desirable to have an institution whick carry out to buy with an adequate price.
16. It is desirable to substantiate the experimental research institute and to promote to train technicians for the future development. For the time being, it is also desirable to consolidate Banmaisamrong Agricultural Experiment Station.
17. It is desirable to carry out to increase the production to 120, 000 tons by 5 year plan in estimating the increasing demand of the world and advantage of the castor seed prrduced in Thailand in the international market, but, on the other hand, the increasing production cannot be developed advantageously unless improvement of the quality is accompanied,

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