Fertilizer regulations

Given the wide variety of natural and synthetic materials that are beneficial to the growth of plants, a virtually unlimited number, of products could truthfully be labeled fertilizer and marketed as such. The main drawback to uncontrolled marketing of fertilizer materials is the problem of the relative effectiveness of the product, and this depends on its composition. Unless the farmer can be sure that each lot of fertilizer he buys will have the same effectiveness as the preceding lot, he cannot be sure that he is fertilizing his crops in a rational man-ner. regardless of his stock of pei nal experience or advice from experts. 

Another drawback to uncontrolled marketing of fertilizer is the lack of a ratimal basis for pricing. A tonne of low-analysis fertilizer is less valuable to fire farmer than a tonne of higher analysis fertilizer therefore, the farmer should have a simple method for determining the best buy from the existir market. 

Because of the foregoing factors, regulations (some of them in the form of laws) have been established in many parts of the world to govern the labelir and marketing of commercial fertilizers at the retail level. These regulations are intended for local conditions and thus may vary from place to place however, thdr primary purposes are to ensure uniformity and to provide a simple method whereby the farmer can select the most economical product available to him. 

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Advances in Methods of Fertility Regulation, Wodd Health Organization Technical Report Series No. 575, Geneva, 1975. 

V. C. Stevens, in G. Benagiano and E. Dic2falusy, Endocrine Mechanisms in Fertility Regulation, Raven Press, New York, 1983, p. 141. 

WHO/HRP Task Force on Postovulatory Methods of Fertility Regulation. Randomised controlled trial of lev-onorgestrel versus the Yuzpe regimen of combined oral contraceptives for emergency contraception. Lancet 1998 352 428-33. 

Hunte, P., M. Safi, A. Macey, and G. B. Kerr. Indigenous methods of voluntary fertility regulation in Afghanistan. Natl Demographic Family Guidance Survey of Settled Population Afghanistan 1975 4 1. 

LT035 Konno, C., A. M. Martin, B. X. Ma, et al. Search for fertility regulating agents from Larrea tridentata. Proc First Princess Chulabhorn Science Congress Bangkok 1989 1989 328-337. 

S. Kang, and H. J. Chi. A review of re- SI131 search on plants for fertility regulation... 

Antiprogestins, such as RU-486 (lift-hydroxy-11/3 (4 dimethylamino phenyl-1 )-17ry-(prop-l-ynyl)-estra-4.9-diene-3-one) (33) and ZK98299 1 l/J-(4-dimethylaminophenyl)-17a-hydroxy-17/j-(3-hydroxypropyl-13a-methyl-4,9-gonadien-3-one) represent a new class of drags for fertility regulation. Also, these drugs have potential applications in the treatment of uterine cancer. 

Briggs MH, Briggs M. Metabohc effects of hormonal contraceptives. In Chang CF, Griffin D, Woolman A, editors. Recent Advances in Fertility Regulation 81 1980 83-111 Beijing. 

Long-acting Agents for Fertility Regulation Bull World Health Organ 1986 64(4) 587-94. 

Croxatta, H.B., et al. 1982. Fertility regulation in nursing women. II. Comparative performance of progesterone implants versus placebo and copper T. Am J Obstet Gynecol 144 201. 

Our experiments, begun in 1968, have demonstrated the reality of such adsorption on the surfaces of intrauterine contraceptives qualitative analyses were made of the spontaneously deposited material. Although evidence for protein denaturation and antibody response was not sought in this study, we do speculate on the importance of such a mechanism in fertility regulation. 

Mechanism of Fertility Regulation. lUDs are successful means of contraception they are particularly suitable for large-scale use when motivation is minimum and continuous surveillance of the population is difficult. For most couples, the use of an lUD in family planning is... 

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