Virus-induced gene silencing of PEAM4 affects floral morphology by altering the expression pattern of PsSOC1a and PsPVP in pea.

pea-MADS4 (PEAM4) regulates floral morphology in Pisum sativum L., however, its molecular mechanisms still remain unclear. Virus-induced gene silencing (VIGS) is a recently developed reverse genetic approach that facilities an easier and more rapid study of gene functions.

[Studies on the megasporogenesis and microsporegenesis and the development of the female gametophyte and male gametophyte in Camptotheca acuminate].

The ovarium is hypostasy in Camptotheca acuminate Decne.. It has a locule and an ovule.

[Morphological studies on direct regeneration of floral buds from in vitro cultures of sepal segments in Sinningia speciosa hiern].

The morphological changes in the cultures of sepal segments in Sinningia speciosa Hiern were observed with Zeiss Stemi 2000-C Stereomicroscope from 0 to 65 days after culture in vitro. The light yellow globular protuberances were observed on the cut edge and the surface of sepal segments after culture for 24 days. Then the globular protuberances grew bigger gradually.

[Studies on the megasporogenesis and microsporogenesis and the development of their female and male gametophyte in Magnolia biloba].

The anther of Magnolia biloba is tetrasporangiate with glandular tapetum, which consists of one or two layers of cells. Cytokinesis during meiosis of its microspore mother cell is modified simultaneous type, and the microspore tetrads are isobilateral. Mature pollen grains are two-celled.

[Studies on calcium sensitive period during floral differentiation of cucumber cotyledonary node cultures in vitro].

Cotyledonary nodes of cucumber cultured on calcium-free medium for 0, 1, 2, 3, 4, 5, 6d respectively, were transferred to medium with 6.0 mmol/L CaCl2 for 24h, then returned to calcium-free medium. Cotyledonary nodes cultured on calcium-free or 6.

[Relationship between floral differentiation and endogenous hormones and polyamines contents in cucumber cotyledonary nodes cultured in vitro].

Changes of endogenous hormones and polyamines(PAs) contents during floral differentiation (0-6 day) in cucumber cotyledonary nodes cultured in vitro were determined by using HPLC. The results showed that all four endogenous hormones decreased obviously within 0-2 day and increased slightly within 4-5 day after culture. This indicated that low levels of indole-3-acetic acid (IAA), gibberelline(GA3) and abscisin acid(ABA) during 0-2 day were favorable to floral primordia differentiation, while high level of zeatin(ZT) during 3-5 day was favorable to floral organ primordia differentiation.

[Floral homeotic variants of in vitro seedlings in Sinningia speciosa Hiern].

Six types of floral homeotic variants of in vitro seedlings were observed in doubleflower sinningia. Type I, red and green mosaic petals exist in the outermost whorl of petal-whorls, 2.38%.