What is radish
- Adapted from the wikipedia definition of radish.
The radish is a root vegetable of the Brassicaceae family. The most popular part for eating is the napiform taproot, although the entire plant is edible and the tops can be used as a leaf vegetable. The skin comes in a variety of colours. Most commonly known is the round, red-skinned variety. Other varieties may have a pink, white or grey-black skin. A large, round yellow-skinned variety has a subtle taste of lemon.
The East Asian giant white radish is called "Chinese radish" or "daikon". It is mild-flavored and is usually called daikon radish in US supermarkets. The most common variety is carrot-shaped, and approximately 8 to 14 inches (20 to 35 cm) long and 2 to 4 inches (5 to 10 cm) in diameter.
The bulb of the radish is usually eaten raw, but tougher specimens can be steamed. The raw flesh has a crisp texture and a pungent, peppery flavour, caused by the concentration of allyl isothiocyanate, also present in mustard, horseradish and wasabi.
Radishes range in sizes, in some instances growing to proportions of over 1 kg (2 lb). They are a popular choice for personal cultivation, as they are fairly easy to grow. It is a rapidly-maturing crop, with many varieties able to reach maturity within 30 days.
Radishes grow best in acidic to neutral soil and require sun and moist, fertile soil. They are best sown from early till late spring and best harvested from late summer till early autumn. The seeds should be planted around 1 cm deep. Ammonium sulfate is an effective fertilizer. However the soil pH level should be checked before planting radishes as they can be sensitive to this.
Why sequence radish
- Radish (Raphanus) is an important crop, a major agricultural pest weed on six continents, and an invasive species of natural areas, especially in California.
- Radish is a model system for studies of ecology and evolution, with major past and ongoing work on population and molecular genetics, plant-insect interactions (both pollination and herbivory), quantitative genetics of floral and life history traits, natural selection through both male and female fitness, adaptation to global change, and the possible role of transgene escape and natural hybridization in the creation of more weedy and invasive genotypes. Thus, we have very broad and deep knowledge of how radish interacts with its abiotic and biotic environment from basic ecology and evolutionary genetics to issues of fundamental applied importance.
- The taxonomic position of radish, as a close relative of Brassica and a more distant member of the same family as Arabidopsis, makes it an ideal candidate for comparative genomics of closely related plant species.
- The wealth of ecological and evolutionary background in this species makes it an excellent candidate to understand adaptation at the molecular genetic level as well as address the applied issues; however, rapid progress in this area is currently hampered by the lack of radish sequence information.
- Sequence eight cDNA libraries, 3 from the crop and 4 from wild radish, from both the 5’ and 3’ ends, to produce abundant EST and full-length cDNA sequence data.
- We will identify orthologs in Brassica and Arabidopsis, and initiate comparative genomic studies in several key areas including evolution in polyploids, gene retention and loss after duplication, and rates of adaptive evolution in an outcrossing plant.
- We will mine these data for codominant markers that will enable a number of research groups to understand adaptation of native, weedy, and invasive radish to its environment through fine scale genetic mapping.
Jeff Conner, PI
Ian Dworkin, co-PI
Shin-Han Shiu, co-PI
Yongli Xiao, co-PI
Cindi Mills, Research Assistant