Tamarind

Common Name: Tamarind
Genus Species: Tamarindus indica
Family: Fabaceae
Origin: East Africa
Cultivated: India, Southeast Asian, West Indies

In India, Thailand, Cambodia, Southern Europe and Latin America, tamarind is a popular cooking and condiment flavor. The tree originated in Africa, but now it is cultivated mainly in South India and in the Caribbean.

A flavouring agent made from the leaf and fruit of the tamarind tree. The fruit is shaped like a long bean, inside which is a sour pulp. The pulp can be pressed to form a 'cake' or processed to make a paste. Small pieces of tamarind cake can be broken off and infused to create an acidic liquid flavouring used in Asian and Caribbean cooking. The sour fruit pulp contains tartaric acid; its taste goes well with meat and vegetable dishes, and it is used in marinades, vindaloos, curries, chutneys and Worcestershire sauce.

Tamarind is also used in drinks and in refreshing confectionary preparations. Tamarind juice is also available and some Asian supermarkets may sell tamarind pods, which can be eaten raw.

An improved Agrobacterium -mediated transformation protocol for recalcitrant elite indica rice cultivars

We report here a high-efficiency transformation protocol for recalcitrant indica rice cultivars IR64 and IR72 with the selectable marker genehph and thegusA reporter gene. Factors that favor high-efficiency transformation were found to be use of 2-month-old mature seed-derived embryogenic calli, maltose as a source of carbon, a higher concentration of 2,4-dichlorophenoxyacetic acid, and both phytagel and agar as gelling agents. The putative transgenic (T0) plants were analyzed for integration of the transgene through polymerase chain reaction and Southern blotting analyses. Various factors thought to be responsible for increased transformation efficiency are discussed.

Source: Plant Molecular Biology Reporter (2005) vol. 23, p. 67-73

Agrobacterium -mediated transformation of the genome-sequenced poplar clone, nisqually-1 ( Populus trichocarpa )

The US Department of Energy recently released a 6.8X draft of the genome sequence for Nisqually-1, a genotype of black cottonwood (Populus trichocarpa). To improve its utility for functional genomics research, having an efficient means for transformation and regeneration is necessary. To examine several parameters known to affect the transformation rate, we cocultivated leaf disc and stem explants with a strain ofAgrobacterium tumefaciens harboring a binary plasmid vector containing genes for both neomycin phosphotransferase (NPTII) and β-glucuronidase (GUS). Shoot regeneration from stem explants was observed in the presence of kanamycin when thidiazuron was incorporated in the selection medium. Transformation efficiency was influenced by the level of thidiazuron to which explants were exposed during the early stages of shoot induction. Histochemical assays revealed expression of theGUS gene in leaf, stem, and root tissues of transgenic plants. Polymerase chain reaction confirmed the presence of both selectable marker and reporter genes in all lines that stained positive for β-glucuronidase activity. By use of our modified protocol, transgenic plants were recovered within 6 mo at an efficiency of 6%, adequate to produce a large number of transgenic events with modest effort.

Source: Plant Molecular Biology Reporter (2004) vol. 22, p. 1-9.