A resurrection has started in haploid and double haploid research in the twenty-first century. The haploid and double haploid could be achieved through in vivo and in vitro anther and microspore culture techniques. Fixing the homozygosity is the most striking benefit of androgenesis. Various factors like genotypic dependency, growth condition, developmental stage of the microspore, pre-treatment, culture media, regeneration media, growth hormones, and various chemicals have a direct effect. Wheat, rice,
Citations
Doubled haploid (DH) technology enables the generation and evaluation of new plant genotypes in ≤ 2 years, which is in stark contrast to the 6-7 years required for conventional breeding. Recently, a few proteins including MATRILINEAL (MTL) were found to trigger haploid induction in monocot plants. However, MTL function in dicot plants remains unclear. Here, we investigate the effects of Arabidopsis PATATIN-RELATED PHOSPHOLIPASE 2A (pPLA-IIa), a maize MTL homolog, on the expression of genes that modulate pollen development and fertilization in Arabidopsis. Quantitative real-time PCR analysis showed that transcript levels of four pollen tube growth-related genes and six pollen guidance- or reception-related genes were increased in the
There is a growing preference for using doubled haploids (DHs) in maize breeding programs because they reduce the time required to generate and evaluate new lines to 2 years or less. However, there is an urgent need for efficient techniques that accurately discriminate between haploid and diploid maize kernels. Here, we investigate the effects of several hormones and chemicals on the germination of haploid and diploid maize kernels, including auxin, cytokinin, ethylene, abscisic acid (ABA) biosynthesis inhibitor (fluridone), ABA catabolism inhibitor (diniconazole), methyl jasmonate (MeJA), and NaCl. Ethylene effectively stimulated the germination of both haploid and diploid maize kernels. The ABA biosynthesis inhibitor fluridone, the ABA catabolism inhibitor diniconazole, and MeJA selectively stimulated the germination of haploid maize kernels. By contrast, gibberellin, 1-naphthaleneacetic acid (NAA), kinetin, and NaCl inhibited the germination of both haploid and diploid maize kernels. These results indicate that the germination of haploid maize kernels is selectively stimulated by fluridone and diniconazole, and suggest that ABA-mediated germination of haploid maize kernels differs from that of diploid maize kernels and other plant seeds.
Citations
We performed a molecular marker-based analysis of quantitative trait loci (QTLs) for the traits that determine appearance quality of the grains using 120 double haploid (DH) lines developed by anther culture from F1 hybrid of a cross between Cheongcheong (
Citations
Pre-harvest sprouting (PHS) of wheat reduces grain yield and has deleterious effects on wheat flour quality. PHS resistance is strongly associated with grain color and seed dormancy. Resistance to PHS is a priority of wheat breeding program. We have studied a population of 122 Doubled Haploid (DH) lines from the cross between two cultivars, ‘Keumkang’ and ‘Olgeuru’, in order to detect QTLs correlated with PHS resistance. PHS was evaluated using mist spray in the humid chamber (PHS-MS), and the germination index (GI) was determined for two years. The variety ‘Keumkang’ has white grains and higher percentage of PHS rate (30.2%), while ‘Olgeuru’ has red grains and lower PHS rate (2.8%). There was significant difference in grain color according to the GI. PHS-MS was positively correlated with GI (r = 0.732,
Citations
The purpose of this study was to produce doubled haploid red color heading type Chinese cabbage using isolated microspore culture. Genotypic differences in embryogenic response and regenerative ability of microspore-derived embryos to plants were observed. A high rate of plant regeneration from microspore-derived embryos was achieved by an improved protocol involving replacement of culture media and adjustment of heat shock temperature. More than 60% of regenerated plants were spontaneous doubled haploids. Haploids were characterized by short and malformed stamen and few viable pollen grains as compared to spontaneous doubled haploids and dihaploids. The seeds harvested from the 142 spontaneous doubled haploid plants were designated as H1; 25 seeds in each population was grown and characterized. The H1 generation has been shown to display considerable phenotypic variation and high purity. These spontaneous doubled haploids may be directly exploited as new varieties in a red colored Chinese cabbage breeding program.
Citations