Premium
Growth and Development in an Oat Mutant Expressing Giantism
Author(s) -
Taylor John S.,
Yeung Edward C.,
Kibite Solomon,
Pharis Richard P.
Publication year - 1995
Publication title -
crop science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.76
H-Index - 147
eISSN - 1435-0653
pISSN - 0011-183X
DOI - 10.2135/cropsci1995.0011183x003500030006x
Subject(s) - biology , panicle , avena , mutant , primordium , inflorescence , apex (geometry) , germplasm , photoperiodism , cultivar , forage , horticulture , botany , raceme , agronomy , zoology , genetics , gene
Sources of germplasm for a forage oat ( Avena sativa L.) program are limited. A recently isolated mutant oat, PI546363, exhibits characteristics (late maturity, tallness, leafiness, and low grain/straw ratio) that are desirable in a forage oat cultivar. As part of an investigation into the genetic/physiological basis for the mutant characteristics, a morphological and anatomical comparison was made between the mutant and its parents (two standard oat cultivars Tibor and OT745) during growth and development. The mutant and its parents were grown in a controlled‐environment chamber (21/17°C, day/night temperature; 16‐h photoperiod; approximately 400 mol m − 2 s − 2 photosynthetic photon flux at canopy height). Measurements of height, tillering, and leaf stage were made, and tissue samples were collected at weekly intervals until panicle emergence. Panicle emergence occurred after 16 wk (1568 heat units) for the mutant, and 6 wk (588 heat units) the parents. At panicle emergence, the mutant averaged 17 leaves compared with eight leaves for the parents; the height of the mutant was approximately 195 cm compared with 96 cm for the parents; and the number of live tillers was similar for both. The shift of the apex from vegetative to reproductive growth occurred at approximately 8 wk in the mutant and at 2 to 3 wk in the parents. The apex of the mutant was longer and larger (i.e., it had increased amounts of parenchymatous tissue), and produced more leaf primordia than its parents. Because of the delay in flowering and the increased vegetative growth, the mutant may be a useful source of germplasm in the development of superior forage oat cultivars.