In hybrid breeding programme based on cytoplasmic-genic
male sterility, the effect of sterility inducing cytoplasm
on agronomic traits is of considerable importance. In rice
(Oryza sativa L.) there are reports showing that sterile
cytoplasm reduced the productive capacity of hybrids
compared with normal cytoplasm of the maintainers. Forty
eight hybrid combinations including 24 AIR hybrids and
their reciprocals were evaluated and mean values for 15
different characters were compared. It was found that
there is significant difference between direct hybrids and
their reciprocals for almost all characters except days to
flowering, total dry matter production, panicle length and
100 seed weight. This difference in performance of these
two sets of hybrids can be attributed to cytoplasmic
effect. Even though these are the average performances
of the two groups of hybrids, when different cross
combinations are compared, it can be seen that these
are cross specific and each cross differs in their
performance. Evaluation of heterosis expressed by different
hybrids revealed that number of reciprocal hybrids
expressing positive and significant heterosis for grain
yield was high compared to direct hybrids. All these
explain the possible negative influence of sterile cytoplasm
on quantitative characters
Keywords: Rice, male sterile cytoplasm, direct hybrids, reciprocal hybrids, heterosis
Year: 2007
Volume: 67
Issue: 1
Article DOI: NA
Print ISSN: 0019-5200
Online ISSN: 0975-6906
C. A. Rosamma and N. K. Vijayakumar info_circle