Quantitative trait loci analysis for rice seed vigor during the germination stage

Abstract

Seed vigor is an important characteristic of seed quality, and rice cultivars with strong seed vigor are desirable in direct-sowing rice production for optimum stand establishment. In the present study, the quantitative trait loci (QTLs) of three traits for rice seed vigor during the germination stage, including germination rate, final germination percentage, and germination index, were investigated using one recombinant inbred line (RIL) population derived from a cross between japonica Daguandao and indica IR28, and using the multiple interval mapping (MIM) approach. The results show that indica rice presented stronger seed vigor during the germination stage than japonica rice. A total of ten QTLs, and at least five novel alleles, were detected to control rice seed vigor, and the amount of variation (R(2)) explained by an individual QTL ranged from 7.5% to 68.5%, with three major QTLs with R(2)>20%. Most of the QTLs detected here are likely to coincide with QTLs for seed weight, seed size, or seed dormancy, suggesting that the rice seed vigor might be correlated with seed weight, seed size, and seed dormancy. At least five QTLs are novel alleles with no previous reports of seed vigor genes in rice, and those major or minor QTLs could be used to significantly improve the seed vigor by marker-assisted selection (MAS) in rice.

Promotive Effect of Priming with 5-Aminolevulinic Acid on Seed Germination Capacity, Seedling Growth and Antioxidant EnzymeActivity in Rice Subjected to Accelerated Ageing Treatment

“…The slow metabolic repair at non-optimum temperatures may have resulted in an increase in the delay in the mean germination time of most deteriorated seeds because of a greater need for repair. However, there were no significant differences in the seed germination capacity between aged and non-aged seeds or priming treatments which might have been due to the high seedling vigor inherited from the genetic background of the rice variety (Wang et al, 2010). Our results suggested that rice seed priming with ALA at 0.5 μg mL -1 could ameliorate the germination capacity even after exposure to the accelerated ageing treatment.…”

Effects of pre-harvest chemical application on rice desiccation and seed quality

“…Bennett and Shaw (2000) showed that reductions in germination, emergence, and seedling growth occurred in soybean when desiccant was applied in the beginning seed (R5) or full seed (R6) growth stages. GP is an estimate of the viability of a population of seeds, and GI is an estimate of the speed and uniformity of germination (Wang et al, 2010;2011). In this study, the chemicals did not significantly reduce GP or GI when applied in 2013 to rice with an MC of about 20%.…”

“…The number of germinated seed was counted every day. Then, the GP and GI after 10 d of germination were calculated using the method described by Wang et al (2010). GI=∑(G t /t), where G t is the number of the germinated seed on Day t. The percentage of normal seedlings (SP) after 10 d of germination was determined.…”

“…Due to the emphasis placed on early planting and rapid and uniform emergence, the quality of seed production is an important issue in rice (Wang et al, 2010;Cheng et al, 2013). Seed development, maturity, and harvest management are critical considerations for maintaining high seed quality (Bewley et al, 2013).…”

The Effect of Gamma Irradiation and Sodium Azide on Germination of Some Rice Cultivars

“…According to Wang et al (2010), the traits of germination, as measured in the laboratory, are able to reflect the ability of plants to live under field conditions. This study aims to analyze the best cultivar response on germination traits, the best mutagen to build cultivars for the germination traits, the best combination between cultivar and mutagen for germination traits.…”