The ultra_morphology and chemical composition of waxes secreted by the scale insect Physokermes shanxiensis (Homoptera: Coccidae) was researched with the techniques of scanning electron microscope (SEM), infrared abso...The ultra_morphology and chemical composition of waxes secreted by the scale insect Physokermes shanxiensis (Homoptera: Coccidae) was researched with the techniques of scanning electron microscope (SEM), infrared absorption spectra (IR) and gas chromatography/mass spectrometry (GC/MS). The result indicated that the scale insect secreted wet wax in its nymph stage. The wet wax coagulated into translucent wax covering on the body surface. However, the female adult secreted its wax secretion with white color and long thread form. According to the infrared absorption spectra characteristic of the waxes, it can be known that the both waxes either from male nymph or female adult were composed by a series of saturated and unsaturated long carbon chain compounds. But the two waxes have different in the chemical functional groups kind and numbers that composed the compounds, because of the differences in absorption peaks numbers and forms which appeared in the two infrared spectra from the wave number 1 800 cm -1 to 1 000 cm -1 . Through detected with GC/MS, 14 compounds with carbon atom number form C 13 to C 32 were obtained form the wax of the male scale insect. These compounds included 5 saturated higher fatty acids, 1 unsaturated higher fatty acid, 1 saturated higher fatty alcohol, 1 unsaturated higher fatty alcohol, 1 unsaturated ester, 1 saturated aldehyde, and 4 saturated alkane compounds.展开更多
Maturing seeds were collected from fifty-year-old trees of Fraxinus mandshurica. The cotyledon and hypocotyl zygotic embryos were excised and cultured on 1/2MS media to induce somatic embryos. In cytological study of ...Maturing seeds were collected from fifty-year-old trees of Fraxinus mandshurica. The cotyledon and hypocotyl zygotic embryos were excised and cultured on 1/2MS media to induce somatic embryos. In cytological study of embryo development, by the way of paraffin, somatic and zygotic embryogenesis was observed and compared under light microscope. The results showed that somatic embryos from zygotic cotyledons originated directly from single epidermis cell. The somatic embryos that indirectly occurred on the embryogenic callus came from its singular surface cell or internal multi_cells. There was an obvious cytological difference between embryogenic and non-embryogenic callus. Somatic and zygotic embryogenesis underwent the similar course, passing through proembryo, heart, torpedo and cotyledonary stages. The important differences in morphogenetic process exited as following: volume of somatic embryos was smaller than its partner at the same development stage; somatic embryos had no obvious suspensors; somatic embryos showed morphologic variations.展开更多
文摘The ultra_morphology and chemical composition of waxes secreted by the scale insect Physokermes shanxiensis (Homoptera: Coccidae) was researched with the techniques of scanning electron microscope (SEM), infrared absorption spectra (IR) and gas chromatography/mass spectrometry (GC/MS). The result indicated that the scale insect secreted wet wax in its nymph stage. The wet wax coagulated into translucent wax covering on the body surface. However, the female adult secreted its wax secretion with white color and long thread form. According to the infrared absorption spectra characteristic of the waxes, it can be known that the both waxes either from male nymph or female adult were composed by a series of saturated and unsaturated long carbon chain compounds. But the two waxes have different in the chemical functional groups kind and numbers that composed the compounds, because of the differences in absorption peaks numbers and forms which appeared in the two infrared spectra from the wave number 1 800 cm -1 to 1 000 cm -1 . Through detected with GC/MS, 14 compounds with carbon atom number form C 13 to C 32 were obtained form the wax of the male scale insect. These compounds included 5 saturated higher fatty acids, 1 unsaturated higher fatty acid, 1 saturated higher fatty alcohol, 1 unsaturated higher fatty alcohol, 1 unsaturated ester, 1 saturated aldehyde, and 4 saturated alkane compounds.
文摘Maturing seeds were collected from fifty-year-old trees of Fraxinus mandshurica. The cotyledon and hypocotyl zygotic embryos were excised and cultured on 1/2MS media to induce somatic embryos. In cytological study of embryo development, by the way of paraffin, somatic and zygotic embryogenesis was observed and compared under light microscope. The results showed that somatic embryos from zygotic cotyledons originated directly from single epidermis cell. The somatic embryos that indirectly occurred on the embryogenic callus came from its singular surface cell or internal multi_cells. There was an obvious cytological difference between embryogenic and non-embryogenic callus. Somatic and zygotic embryogenesis underwent the similar course, passing through proembryo, heart, torpedo and cotyledonary stages. The important differences in morphogenetic process exited as following: volume of somatic embryos was smaller than its partner at the same development stage; somatic embryos had no obvious suspensors; somatic embryos showed morphologic variations.
基金supported by the Grant fromthe National Nature Science Foundation of China(No.30471398)the Grant from the National Nature Science Foundation of Shanxi Province(20051066)
