Awn In Rice

Here we identified a recessive mutant gene grain length and awn 1 gla1 which caused a significant increase in grain length and weight and was associated with long awns the gla1 mutation was mapped to a single nucleotide polymorphism in a gene encoding a cytoplasmically localized mitogen activated protein kinase mapk.

Awn in rice.

2010 improvements in grain size are directly associated with yield therefore grain size and. In domesticated rice elongation of the awn is partially or completely suppressed in most strains of o. In grasses awns typically extend from the lemmas of the florets this often makes the hairy appearance of the grass synfloresce. It was also reported that the genes controlling awn length in rice were always associated with pleiotropic effects on other agronomic traits.

Width ratio rice grains are divided into three size classes namely long medium and short grain for which the ratios range from greater than 3 0 2 1 2 9 and less than 2 respectively bai et al. Rice oryza sativa l is an important cereal crop throughout asia on the basis of the length. Late japonica rice lines nk58 nk58s and nk58sr reportedly showed responses to day length. In botany an awn is either a hair or bristle like appendage on a larger structure or in the case of the asteraceae a stiff needle like element of the pappus.

The causal genetic factors responsible for the loss of awn in these two rice species remain largely unknown. A panicle of wild rice tk212 is illustrated in the lower right corner. Awns are characteristic of various plant families including geraniaceae and many grasses. Sativa a wild rice typically bears a long barbed awn which aids in seed dispersal and deters large predators such as birds.

Awn development in rice is also influenced by environment. Rufipogon and cultivated rice o. This organ is thought to aid in seed dispersal and prevent predation by animals. Grain size is an important factor determining yield in rice.

No awns in panicles were observed under short day conditions but under long day conditions long awns protruded from the apices of lemmas 32. Most cultivated varieties of oryza sativa and oryza glaberrima however have lost the ability to form long awns. A long awn is one of the distinct morphological features of wild rice species. The awns of wild rice o.

In rice most wild species which belong to the genus oryza generate a long awn on the lemma oka 1988. For example an 1 and an 2 not only regulated awn development but also grain size grain number and other grain characteristics 15 16. B cultivated rice has either no awns or short and barbless awns and suffers from significant bird predation. Japonica whereas many strains of o.

Grass species often harbor long awns. Bar 10 cm.