Premium
Modification of nitrogen remobilization, grain fill and leaf senescence in maize ( Zea mays ) by transposon insertional mutagenesis in a protease gene
Author(s) -
Donnison Iain S.,
Gay Alan P.,
Thomas Howard,
Edwards Keith J.,
Edwards David,
James Caron L.,
Thomas Ann M.,
Ougham Helen J.
Publication year - 2007
Publication title -
new phytologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.742
H-Index - 244
eISSN - 1469-8137
pISSN - 0028-646X
DOI - 10.1111/j.1469-8137.2006.01928.x
Subject(s) - biology , mutant , wild type , senescence , mutagenesis , insertional mutagenesis , transposable element , population , chlorophyll , oryza sativa , poaceae , botany , genetics , gene , demography , sociology
Summary• A maize ( Zea mays ) senescence‐associated legumain gene, See2β , was characterized at the physiological and molecular levels to determine its role in senescence and resource allocation. • A reverse‐genetics screen of a maize Mutator ( Mu ) population identified a Mu insertion in See2β . Maize plants homozygous for the insertion were produced. These See2 mutant and sibling wild‐type plants were grown under high or low quantities of nitrogen (N). • The early development of both genotypes was similar; however, tassel tip and collar emergence occurred earlier in the mutant. Senescence of the mutant leaves followed a similar pattern to that of wild‐type leaves, but at later sampling points mutant plants contained more chlorophyll than wild‐type plants and showed a small extension in photosynthetic activity. Total plant weight was higher in the wild‐type than in the mutant, and there was a genotype × N interaction. Mutant plants under low N maintained cob weight, in contrast to wild‐type plants under the same treatment. • It is concluded, on the basis of transposon mutagenesis, that See2β has an important role in N‐use and resource allocation under N‐limited conditions, and a minor but significant function in the later stages of senescence.