Pollen Tube Growth and Fertilization Efficiency in Salpiglossis sinuata: Implications for the Involvement of Chemotropic Factors

The possible involvement of chemotropic factors influencingpollen tube growth in the style and ovary of Salpiglossis wasstudied. Pollen deposited at the base of excised styles germinatedreadily, with pollen tubes penetrating the transmitting tissueand growing towards the stigma, implying that no chemotropicrequirement exists for pollen tube growth in the style. However,the position and high efficiency of seed set following limited-pollinationof intact pistils would support the involvement of localizedchemotropism operating within the ovary. Chemotropism, limited pollination, fertilization efficiency, Salpiglossis sinuata     

Development of a Superficial Meristem During Somatic Embryogenesis from Immature Cotyledons of Soybean (Glycine max L.)

Initial events were studied in the development of an embryogenicmeristem during somatic embryogenesis from in vitro culturedimmature cotyledons of soybean. The presence of 2,4-D in theculture medium led to the formation of a superficial embryogenictissue associated with the abaxial epidermis of 3 mm cotyledons.Additionally, 2,4-D initiated rapid non-morphogenic periclinaldivision in the parenchyma tissues of the cotyledon. Consequentinternal expansion disrupted and eventually ruptured the apparentlyquiescent adaxial epidermis. The profound difference in thein vitro response between abaxial and adaxial epidermes is discussedin relation to their relative roles in nutrient transport duringseed development in vivo. Somatic embryogenesis, transfer cells, Glycine max