Analysis of Protein and Isoenzyme of LiLum davidii var.unicolor,Lilium Asiatic Hybrids and Their Hybrid F_1

[Objective]The paper was to provide theoretical basis for selection of parental combination and early identification of hybrids.[Method]The soluble protein and peroxidase of LiLum davidii var.unicolor,Lilium Asiatic hybrids and their filial generations were analyzed using polyacrylamide gel electrophoresis technique.[Result]The protein spectrum of filial generation with L.davidii var.unicolor as parent not only appeared the homologous band as parent with darker coloring,but also had new bands compared with parent.Peroxidase zymogram of hybrid F1 mainly displayed incomplete complementary and hybrid type of parent.[Conclusion]Protein spectrum and peroxidase zymogram could be used as the biochemical markers for the identification of hybrids of lily,which could also detect the target traits of plant.

Polyploidy Induction and Morphological Characteristics in the Asiatic Hybrid Lily(Lilium spp.cultivar dazzling)

The Asiatic hybrid lily cultivar Lilium dazzling(family Liliaceae)is a perennial herbaceous bulbous plant with bright yellow flowers of ornamental values.It also shows resistance to diseases and abiotic stress,making it an ideal parent for breeding studies.This study established a sterile culture system using scales of dazzling lily as explants to induce polyploidy.Adventitious buds growing to 1 cm were treated with different concentrations of colchicine(125,250 and 500μmol·L-1),pendimethalin or trifluralin(100,200 and 300μmol·L-1,respectively)for 12,24 and 36 h.Flow cytometry and chromosome counting were used to identify ploidy,and the phenotype of the polyploids was examined by stomatal observation and leaf index determination.With increasing mutagen concentration and exposure time,the mortality and mutagenic rate increased.The optimal treatment group was:300μmol·L-1 trifluralin for 12 h,which resulted in 15.55%mortality rate and 42.22%induction rate.The polyploid plants showed a significant increase in stomata length,leaf length and leaf width,with a decrease in stomatal density compared with the control plants.This study provided a basis for polyploid breeding.

Cytological and Molecular Characteristics of Pollen Abortion in Lily with Dysplastic Tapetum

Lily was grown worldwide as a fresh cutting flower because of its colorful petals, but its anther contained a large number of pollen grains that cause serious pollen contamination, however, pollen abortion can effectively reduce the level of pollen pollution. Our analysis aims to use cytological observation to detect the critical stage when pollen abortion occurs and to provide comprehensive gene expression information at the transcriptional level. The result showed that pollen abortion in ‘Little Kiss’ began at the mononuclear stage and the callose that covers the microspores failed to degenerate when young pollens were released from the tetrads. In addition, compared with the normally developed one,the tapetum of ‘Little Kiss’ degraded in advance while the degradation of callose was delayed. Furthermore, 103 differentially expressed genes(DEGs) related to the advance degeneration of tapetum cells and callose were found in the expression levels, including 22 transcription factors(TFs). In particular, two β-glucanase genes(endo-1,3(4)-β-glucanase, exo-β-glucanase) responsible for callose degeneration were significantly down-regulated. These results suggested that pollen abortion may occur at mononuclear stage and that early degeneration of tapetum cells resulted in a significant down-regulation of β-glucanase genes. As a result, the callose to cover microspores impedes the formation of pollen walls, which may possibly lead to pollen abortion.