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WonderPlant genetics biography

The Indian botanist Janaki Ammal studied plant chromosomes and used that knowledge to help breed sweeter sugarcane suited to India's climate. In 1945 she co-wrote the Chromosome Atlas of Cultivated Plants, a reference to the chromosome counts of crops and garden plants.

Janaki Ammal

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The story behind the card

Chromosomes are the thread-like structures in a cell that carry its genes, and their number helps explain which plants can be crossed. Janaki Ammal earned her PhD at the University of Michigan in 1931, rare for an Indian woman at the time. India then imported its sweetest sugarcane from Southeast Asia; at the Sugarcane Breeding Station in Coimbatore she crossed cane with related grasses to produce sweet varieties that grew well in India. In England she worked with the geneticist C. D. Darlington at the John Innes Institute, her co-author on the atlas, and then at the Royal Horticultural Society's garden at Wisley, where she treated magnolias with the chemical colchicine. A white-flowered magnolia there is named 'Janaki Ammal'. The Indian government later invited her home to reorganise the Botanical Survey of India, and she received the Padma Shri in 1977.

Türkçe oku
Hintli botanikçi Janaki Ammal bitki kromozomlarını inceledi ve bu bilgiyle Hindistan'ın iklimine uygun, daha tatlı şeker kamışı çeşitlerinin geliştirilmesine katkıda bulundu. 1945'te, tarım ve bahçe bitkilerinin kromozom sayılarını derleyen Chromosome Atlas of Cultivated Plants adlı başvuru kitabının yazarlarından biri oldu.

Kromozomlar, hücrede genleri taşıyan iplik biçimli yapılardır; sayıları, hangi bitkilerin birbiriyle melezlenebileceğini anlamaya yardım eder. Janaki Ammal 1931'de Michigan Üniversitesi'nde doktorasını tamamladı; bu, o dönemde bir Hintli kadın için çok ender görülen bir başarıydı. Hindistan en tatlı şeker kamışını o yıllarda Güneydoğu Asya'dan getiriyordu. Ammal, Coimbatore'daki Şeker Kamışı Islah İstasyonu'nda kamışı akraba otlarla melezleyerek Hindistan'da iyi yetişen tatlı çeşitler elde etti. İngiltere'de önce John Innes Enstitüsü'nde, atlası birlikte yazdığı genetikçi C. D. Darlington'la çalıştı; ardından Kraliyet Bahçecilik Derneği'nin Wisley'deki bahçesinde manolyalara kolşisin adlı kimyasalı uyguladı. Oradaki beyaz çiçekli bir manolya çeşidi bugün “Janaki Ammal” adını taşır. Hindistan hükümeti daha sonra onu Hindistan Botanik Araştırmaları Kurumu'nu yeniden düzenlemesi için ülkeye çağırdı. 1977'de Padma Shri nişanını aldı.

Sources and further reading

Background reading: Janaki Ammal
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