|Growing radish plants|
Radish is an edible root vegetable known by the scientific name Raphanus sativus. Although they are mainly cultivated as a food crop mainly for their large root which is often eaten as a crunchy salad addition, some other varieties are grown as a cover crop or for oil production.
The accumulated storage in radish taproots form pronounced fleshy bulbs. As biennials, humans harvest radishes at the end of the first season after the greatest amount of nutrients have been translocated to the roots, which swell as parenchyma tissue in the xylem proliferates, or grow by multiplication of parts. Radishes possessing red color were mutations that were developed in the eighteenth century as a result of human selection, and have been continued on since then. They are approximately 95% water, and have eighteen diploid chromosomes.
The rosette leaves are lyrate, divided transversely into several lobes, pinnatifid and vary in size from 10cm to 15cm in small rooted cultivars to 45 cm in large rooted cultivars. The seeds are yellowish when mature and turn reddish brown with age.  The tap root, which is a large central root utilized primarily for storage, is characteristic of dicotyledons. It stores the starches that are produced in photosynthetic sources and transported by phloem vessels. 
Radish is an annual or biennial depending on the ecotype or cultivar. It reproduces by round or oval seeds produced from seed pods of a mature plant. In 22 to 70 days after planting, the seeds produce roots that are fit for cultivating. Winter radishes require a longer growing period than spring radishes. When the radish is left in the ground long enough or grows in weather that is too hot, the plant enters a bolting stage. As the stalk reaches 3 feet tall or taller, it produces white or pink cross-shaped flowers. The roots become woody and inedible at this point.
Flowers pollinate through the help of pollinators such as butterflies or bees. The pollinated flowers eventually grow into fleshy seed pods that harden over time. Cultivated radishes possess five seeds, a distinct difference from wild radishes which have ten seeds in their seed pods. 
Radish originated from Europe and Asia. It is believed to have originated from Raphanus raphanistrum, a widely distributed weed crop in Europe. It requires friable soil, loose with small particles, and grows best during winter in plains and spring-summer in hills of North India.
Radishes have had a long relationship with man.  They are fast-growing plants that are very easily cultivated. Since plants are susceptible to drought, irrigation is required. Through centuries of cultivation, numerous varieties varying in shape, size and skin colour of roots and duration of crop have emerged: Raphanus sativus, R. sativus caudatus, R. sativus niger, R. sativus oleiformis, and etc. 
Radish is commonly grown to cultivate the tender tuberous roots which are eaten raw as salad or as cooked vegetable. Radish has a cooling effect which prevents constipation and increases appetite. Young leaves are also cooked as vegetable since it is more nutritious when cooked with leaves. Patients suffering from piles, liver troubles, jaundice etc. are recommended the consumption of radish. 
Oilseed radish (Raphanus sativus var. Oleiferus) is a type of mustard originally developed for oil production. It is widely used in Canada and is being adapted throughout Michigan as a cover crop. It has a thick, deep root that can help break up compacted soil layers and scavenge nitrate that has leached beyond the rooting zone of other crops. It also grows fast in spring or fall providing quick ground cover to protect against soil erosion and smother weeds.
Corn and soybeans serve as great crops for use in ethanol and biodiesel production. However, these crops are consumed by livestocks and people. Engineers of University of Georgia sought oilseed radish as a non-food crop that can be used to make alternative fuels.Although radish is widely grown in Canada as a cover crop which is meant to improve soil quality preventing field erosions, it is not typically grown for food.  Saving land for both food production and fuel production, oilseed radish seems to be a fitting plant for biodiesel production.
Top 5 Benefits of Radish
- Classification.USDA. Web. accessed on 7 May 2016,unknown author
- Caitlin and David. The Role Soils Play in Determining the Flavor of a Plant. "Amador Valley High". Web. accessed on 16 May 2016.
- Gopalakrishnan, T.P. (2007). Vegetable Crops. New India Publishing. pp. 244–247. ISBN 978-81-89422-41-7.
- Hessong, Athena. Radish Plant Growing Cycle. "Home Guides". Web. accessed on 16 May 2016.
- Raphanus sativus."Missouri Botanical Garden". Web. accessed on 15 May 2016. auther unknown
- Raphanus sativus."Practical Plants". Web. accessed on 22 May 2016. unknown author
- Cavigelli, Michel A. Todd E. Martin and Dale R. Mutch Oilseed Radish."W.K. Kellogg Biological Station Extension, Michigan State University". Web. accessed on 15 May 2016.
- Dowdy, Sharon Georgia looking at radish oil for biofuel market."Southeast Farm Press".4 June 2009. Web. accessed on 15 May 2016.