Genetic basis of dormancy and differential response to sodium azide in Avena fatua seeds

Abstract

Seven crosses, involving either nondormant × dormant or dormant × dormant pure lines of wild oats (Avena fatua L.), were made. Selfing of the hybrid and further hybridization were carried out to produce the F2 and reciprocal backcross generations. The seed germination time-course curves of the parents, their F1, and segregating generations over a 20-week period were studied. Differences in time course of germination in these generations were interpreted in terms of a minimum of three interacting loci. Two pure lines, AN51 and MO73, differed in their response to sodium azide, a respiratory inhibitor, with the former being more responsive. In crosses between these lines, the F1 seeds were also more responsive when AN51 was used as the maternal parent. This differential response of two dormant pure lines and their reciprocal F1s suggests maternal influence in germination response to sodium azide.

Multiple Loci and Epistases Control Genetic Variation for Seed Dormancy in Weedy Rice (Oryza sativa)

“…environmental conditions after maturation and separation from the parent plant (Simpson 1990 1986;Jana et al 1988;Bhatt et al 1993; at 40 days after flowering and immature seeds were removed. Fennimore et al 1999;Gu et al 2003).…”

“…Bagged panicles were fixed to epistases for the control of dormancy have been postubamboo poles to prevent shattering during seed development lated for rice, wheat, and wild oat ( Johnson 1935; Seshu due to brushing or shaking the plant. Seeds were harvested and Sorrells 1986; Jana et al 1988;Bhatt et al 1993; at 40 days after flowering and immature seeds were removed. Fennimore et al 1999;Gu et al 2003).…”

“…Classical genetic analyses usually attribute experiment is similar to the within-line variation in the the variations in the pattern or estimate to the change greenhouse experiment and is likely due to microenviin number of effective dormancy genes with the time ronmental variation. The low heritability of 0-0.56 of after-ripening ( Jana et al 1988;Bhatt et al 1993;(Chang and Yen 1969;Jana and Naylor 1980;PaterFennimore et al 1999;Gu et al 2003). A majority of son and Sorrells 1990) implies that microenvironthe epistases, and especially those involving three or mental variation under field conditions is usually more QTL, were detected at 11 DAR, when heritability greater than that in the greenhouse (Table 3).…”

Dormancy Genes From Weedy Rice Respond Divergently to Seed Development Environments

“…Subsequent research using classical genetic approaches added nonallelic interaction to the model ( Jana et al 1979( Jana et al , 1988Fennimore et al 1999;Gu et al 2003) and emphasized environment and genotype-by-environment (G 3 E) interaction effects (Chang and Yen 1969;Upadhyay and Paulsen 1988;Paterson and Sorrells 1990). Recently, the Mendelian factors associated with seed dormancy were resolved as quantitative trait loci (QTL) in major cereal crops to seek dormancy genes that impart resistance to preharvest sprouting (PHS) in breeding (Anderson et al 1993;Ullrich et al 1993;Lin et al 1998;Lijavetzky et al 2000) and in wild and weedy species to determine evolutionary and genetic mechanisms underlying the adaptive trait and germination (Cai and Morishima 2000;Alonso-Blanco et al 2003;Gu et al 2004;Zhang et al 2005).…”

Genetic and physiological characterization of seed dormancy regulation in common waterhemp [Amaranthus tuberculatus (Moq) Sauer]

“…Quantitative trait loci (QTL) techniques have been used to detect loci that are related to dormancy in several species (Li and Foley 1997), including wild oat (Fennimore et al 1999;Jana et al 1988;Li and Foley 1997), rice (Oryza sativa L.) (Wan et al 1997); barley (Hordeum vulgare L.) (Han et al 1996(Han et al , 1999Larson et al 1996), wheat (Triticum aestivum L.) (Paterson and Sorrells 1990), and Arabidopsis ). In addition, many genes and proteins have been associated with post-germinative events.…”