TY  - JA
AU  - Vasal,S.K.
AU  - Dhillon,B.S.
AU  - McLean,S.D.
AU  - Srinivasan,G.
AU  - Zhang,S.H.
AU  - Crossa,J.
TI  - Improvement in selfed and random-mated generations of four subtropical maize populations through S3 recurrent selection
SN  - 1573-5060
PY  - 1995///
KW  - Inbred lines
KW  - AGROVOC
KW  - Lowland
KW  - Random mating
KW  - Research projects
KW  - Selection
KW  - Selfing
KW  - Tropical zones
KW  - Zea mays
KW  - Hybrids
KW  - CIMMYT
N1  - Peer-review: Yes - Open Access: Yes|http://science.thomsonreuters.com/cgi-bin/jrnlst/jlresults.cgi?PC=MASTER&ISSN=0014-2336
N2  - In maize (Zea mays) source germplasm having tolerance of inbreeding is needed for the derivation of productive inbred lines. Germplasm with non-temperate adaptation generally suffers greatly from inbreeding depression (ID). The objective of the present study was to improve four white subtropical populations for tolerance to ID through S3 recurrent selection. Two cycles of selection were conducted and the effect of selection was evaluated in the first selfed (S1) and random-mated (Syn-2) generations. To complete each cycle, 200 to 250 S3 progenies were evaluated and 15 to 20 superior ones selected for recombination in each population. Selection was practised for high grain yield, vigour and other agronomic traits. The S1 and Syn-2 generations of the original (C0) and improved (C1, C2) populations were evaluated in a split-split plot design, with populations in main plots, generations in subplots and cycles in sub-subplots. In all populations, S1 and Syn-2 generations of C2 were significantly higher yielding than the C0 and the linear gain per cycle varied from 16.3 to 28.8% in the S1 generation and 5.5 to 10.7% in the Syn-2 generation. Selection reduced the anthesis-silking interval but slightly increased plant height, grain moisture and days to silk. An increase in plant height was expected because of emphasis on vigour during selection. For grain yield, ID decreased from 48.4% in C0 populations to 37.9% in C2, indicating an improved tolerance of inbreeding. Furthermore, the selection accumulated favourable alleles; and Pop. 42 seemed to be the best source population for deriving high yielding inbred lines. It may be concluded that S3 recurrent selection was effective in improving grain yield and the improved populations would provide better germplasm sources for the derivation of productive inbred lines
T2  - Euphytica
ER  -