Waxy mutation

A mutant tetraploid durum wheat that reduces amylose content has lead to the discovery of full and partial durum wheats. According to Vignaux et al. (2004), the waxy mutation did not affect grain yield, kernel size, or hardness. However, waxy cultivars contained more alpha amylase activity and lower semolina yield. The commercial growth of high yielding waxy durum wheats will bring new beneficial applications and probably new markets to the industry. 

The ratio of amylose to amylopectin produced by a plant is under genetic control. Waxy maize is a natural mutation of maize that happens to produce almost pure amylopectin. 

One of these spontaneous mutants gave rise to the precious sticky rice of Thailand. The sticky rice lacks the starch amylose, which constitutes up to 30% of the total starch in nonsticky rice endosperm. The lack of amylose is due to a mutation in a gene called Waxy, which encodes an enzyme required for amylose synthesis (Sano 1984). Sticky rice is an important culinary and cultural component throughout East Asia and is used in festival foods and desserts. In upland regions of Southeast Asia, it is a staple food in many homes. Ten percent of the rice traded each year is sticky rice. 

The main ingredient in Thai sticky rice is rice carrying a mutation in the Waxy gene. Ingredients... 

Five plant systems or types of study have been selected for coverage in this report plant cytogenetic analysis, chlorophyll mutations, the Tradescantia stamen hair test, the maize waxy locus system, and plant metabolic activation systems. Descriptions of other plant systems may be found in the proceedings of workshops on the use of higher plants as monitors for environmental mutagens94 and on the use of pollen systems to detect biologic activity of environmental pollutants.71... 

Chromosomal aberrations including the waxy locus are perceived as mutants before haplontic selection sets in, enhancing the sensitivity of the pollen method. Thus irradiation or treatment with EMS of barley seeds leads to sectors with waxy pollen in up to 50 percent of the spikes, whereas very few mutations are transmitted to the following generation cf, Eriksson, 1969 Amano and Smith, 1965). 

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