Plastome-genome incompatibility (PGI) is prevalent in several plants including the Zantedeschia species, a worldwide commercial flower crop native to South Africa. Generally, hybrids suffering from PGI appear less vigorous and more susceptible than normal plants. Previous reports revealed that the PGI level in interspecific hybrids is correlated with the relatedness of the parental species in the genus Zantedeschia. To provide a basis for utilizing and improving resources in breeding programs, a total of 117 accessions of colored calla lily (Zantedeschia hybrid), collected from New Zealand, the Netherlands and the United States, were genotyped using 31 transferable expressed sequence tags-simple sequence repeats (EST-SSR) markers from the white calla lily (Zantedeschia aethiopica). A moderately high level of genetic diversity was observed, with 111 alleles in total, an observed/expected heterozygosity (Ho/He) of 0.453/0.478, and polymorphism information content (PIC) of 0.26. Genetic distance and STRUCTURE-based analysis further clustered all accessions into four subgroups (G-Ia, G-Ib, G-IIa and G-IIb), which mostly consisted of Zantedeschia pentlandii, Zantedeschia elliotiana, Zantedeschia albomaculata and Zantedeschia rehmannii, respectively. Significant genetic differentiation was observed between all inferred subgroup pairs, with the Fst ranging from 0.142 to 0.281. Finally, the accessions assigned into G-IIb (Z. rehmannii) were recommended as top priority parents in efficient Zantedeschia breeding program designs.

Seven interspecific crosses of Tagetes erecta × T. patula were conducted in this study. The cross compatibility index, seed setting rate, germination rate, phenotype, ploidy level, heterosis over male parent and field performance were tested. The results showed that different cross compatibility indices of Tagetes vary greatly, from 10.44~114.41, which is far less than that of the intraspecific hybridization S-121 × I-506 index. The seed setting rate of each cross ranged from 15.67% to 49.0%, and the cross S-121 × TP-512 scored the highest seed setting rate, which was higher than that of the intraspecific cross S-121 × I-506 (35.85%). Compared with the male parent, F1 has higher plant height, wider crown width, larger flower diameter and more ray florets and earlier bloom with two exceptions. The S-121 of T. erecta was diploid. All of the male parents of T. patula were tetraploids, and the combinations were triploids. The traits of plant height, plant width, flower size and number of ray florets showed positive heterosis over the male parents, and the days leading to flowering showed both positive and negative ones. Finally, S-121 × TP-379 and S-121 × TP-512 were selected as the two best combinations. This study confirmed that the two species of marigold could be crossed for better F1 varieties with improved performance. ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 3, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********

Naturally occurring yellow leaf mutants are an important resource for studying pigment content and biosynthesis, as well as related gene expression. In our ongoing cultivation of Rehmannia chingii H. L. Li, we found an off-ty... | Find, read and cite all the research you need on Tech Science Press