Lateral root occurs from some special cells in the pericycle of parent root. Lateral root initiation, lateral root primordium formation, and formation and activation of lateral meristem are some key stages for lateral root formation. Auxin action is involved in all the stages of lateral root formation, and jasmonic acid has some effects on the regulation of lateral root formation too.

Gene targeting is a molecular technique that has been exited since 1980’. It can be applied in researching the gene function, removing gene silence and gene therapy. Gene targeting is an important method in functional genetics. Now, it has been successfully used in yeast and mouse embryonic stem cells(ES). But in plants it has been limited because of lower recombination frequency. The recombination frequency in Physcomitrella patens is high, so it is expected to be a new molecular biological model plant.

Calcium is the second messenger involved in multiple signal transduction pathways. Distribution of ［Ca2+］cyt in guard cell and changes of ［Ca2+］cyt in duced by exogeneous stimuli can be showed by using Ca2+fluorescent imaging technique, and the mechanisms of Ca2+release from intracellular and extracell ular Ca2+pools are partially revealed. The Arabidopsis mutants in some given sites show that those components also involved in Ca2+signal transduction pathway and provide molecular evidences for Ca2+signaling in guard cell. Other essential processes are phosphorylation and dephosphorylation which are downstream of [Ca2+］cytelevation.

Resveratrol is a kind of important phytoalexin that has many functions for health and medical treatments, so its extensive application prospect has already caused attention in many ways. Resveratrol synthase is an exclusive necessary enzyme in the pathway of resveratrol biosynthesis, which catalyzes one molecule of 4-coumaroyl-CoA and three molecules of malonyl-CoA into resveratrol.The research about it has extensively developed. This article give some discuss ion in the fields of pharmacologic activity of resveratrol, and zymological char acter, pathway and mechanism of induction, molecular biology of resveratrol synthase.

CDPKs play important roles in the plant calcium signal transduction. Based on plant calcium signal transduction, and structure and biochemical properties of CDPKs, potential regulatory roles of CDPKs in gene expression, metabolism,traffic of ions and water across membranes,the dynamics of the cytoskeleton, stomatal movement, as well as growth and development were summarized. Recognitions and challenges in CDPK studies were also put forward.

For ornamental plants, flowering is an important development phase that directly influences the quality of flower. In recent years, researches on plant flowering in the field of molecular biology developed very fast and some break throughs have been obtained. As a second messenger, calcium plays a very important role in plant signal transduction. Many evidences show that calcium may be related to flowering control. The present review attempts to highlight the recent advances in research of calcium signaling and flower development, which contains the following aspects: the role of calcium in the induction of flowering (including photoperiodic induction and vernalization); dynamic distribution of calcium in leaf buds and flower buds during flower bud differentiation; the influence of different calcium concentrations on in vitro flower bud differentiation; the relation between calcium signal transduction and flower senescence.

In this article the follow aspects about chitin and its derivatives are discussed:1)the chemical and cellular characteristics of chitin and its derivatives; 2)the effect of chitin and its derivatives on growth, development and induced resistance of plants as well as relevant mechanism; 3) the prospect for application of chitin and its derivatives in agriculture.

Elicitors are used as important mean of regulating secondary metabolites biosynthesis in studing taxol production in Taxus cell cultures. The stimulation of biotic and abiotic elicitors in taxol biosynthesis are summarized in this paper. Besides, their probable reaction mechanisms are also discussed.

Photorespiration is an important metabolic process in C3 plant，which is one of the highlight of research on photosynthesis. In the article，we elucidate the photorespiratory normal metabolic pathways and alternative pathway of glyoxylate metabolism and function of alternative pathway. The biological characters of key enzymes are discussed. The biologic functions of photorespiration in alleviating stress damage，slowing the degradation of chlorophyll，driving the Calvin Cycle，participating in TCA、nitrogen metabolism、protein accumulation and state transition are summarized.

In the report, the gramineous expression vectors pGU4AGBar and pGBIU4AGBar were used, respectively. The sgna gene, a synthetical agglutinin gene of Galanthus navies, had been transferred into the winter wheat varieties Xinong 2208 and Xinong 132 by pollen-tube pathway. The PCR and Southern blotting analysis showed that 20 transgenic plants with sgna gene were obtained. Western blot ting analysis revealed that the target protein was expressed in the transgenic plants. The transformation frequency were 0.28%～0.84%.

Grown in BG11 liquid medium with 0.05 mol/L chloride, nitrate, sulphate and phosphate of K+, Na+ and ammonium ion for 2 days, the cells of Anabaena sp. 595 inflated, vacuolized and performed longitudinal or unequational division; the trichomes fragmented and the number of heterocysts increased. And special contracted granules appeared in the cells when they were treated by ammoniumions. In comparison, the cells were less affected by Ca2+ and Mg2+. While cultured in the medium containing 0.01mol/L NaCl for long-term, the cells exhibited cyclic diff erentiation. It inflated and vacuolized firstly, then the pigment expanded and vacuolization disappeared, finally, the cell divided to normal size. In fact, the inflation and vacuolization appeared again in the following days, so the cycle continued.

The changes in Ca2+ localization in the leaf cells of Garyota urens L. under chilling stress were investigated with calcium antimonate precipitate-electromicros copic-cytochemical methods. When Garyota urens L. grew on the normal temperature, it was shown that the deposits of calcium antimonate being the indicator for Ca2+ localization mainly concentrated within the vacuoles and intercellular spaces and there was also some Ca2+ deposits in cell walls. But when Gar yota urens L. was treated by the temperature of 2℃ for 48 h, the level of Ca2+ increased in cytoplasm and plasma membrane, but decreased in vacuoles and intercellular spaces considerably. At the same time, the ultrastructure of chloroplasts suffered from chilling: the membrane of chloroplasts had been damaged, the layer of thylakoids was exiguous and unclear, the photosynthetic rate decreased evidently. And when Garyota urens L. was treated by the temperature of 2℃ for 120 h , the deposits of Ca2+ mainly concentrated within the cytoplasm, nucleus and plasma membrane and there was also some Ca2+ deposits in vacuoles, and the ultrastructure of some cells was simultaneously damaged severely: Chloroplasts structure, vacuole membrane and nuclear membrane had been damaged fully, the structure within the cell had become unclear, and the cell only have respiration. Thus it can be seen that there are some relations between the changes in Ca2+distribution within the cell and plant cold-hardiness.

Extracellular matrix (ECM) plays a very important role in the course of interaction between pistil and pollen, especially in recognition and guidance of pollen tube. ECMs associated with pollen tube growth include arabinogalactan proteins, extensin-like glycoproteins, proline-rich proteins, calmodulin, S-glycoproteins, pectins and those that specifically located in the ovary. Here were reviewed the common classes of the ECMs and their physiological functions.

TDZ(N-phenyl-N’-1,2,3-thidiazol-5-yl-urea) is a substituted phenylurea compound and has emerged as a highly efficacious bioregulant of morphogenesis in the tissue culture of many plant species. Application of TDZ induces a diverse array of cultural responses ranging from induction of callus to formation of somatic embryos.TDZ exhibits the unique property of mimicking both auxin and cytokinin effects on growth and differentiation of cultured explants. The recent app roaches applied to study the morphogenic events initiated by TDZ are clearly beginning to reveal the details of a variety of underlying mechanisms. Various reports indicate that TDZ may act through modulation of the endogenous plant growth substances, or as a result of induced stress. The other possibilities include the modification in cell membranes, energy levels, nutrient uptake, or nutrient assimilation. In this review, several of these possibilities are presented and summarized in light of recently published studies on characterization of TDZ-induce dmorphogenic effects.

Germination or dormancy of seeds depends on the content of Pfr and Pfr/(Pr+Pfr) ratio established in photosensitive seeds. The level of Pfr in seeds is affected by multiple factors. The non-photoblastic seeds contain appropriate Pfr level when ripen and the light-favored seed does after being irradiated with white light or red light to some degrees, but light-inhibited seeds can germinate only when they contain low Pfr after long duration in darkness. The seed photosensitivity is not absolute and influenced by the environmental conditions of mother plant, maturation degrees, storing status of seed itself, spectral composition, fluence rate, photoperiod, germination temperature, O2 supplying state and treatments with chemicals.

Material of genetic male sterility is a valuable species resources.This paper summarizes the progress in discovery, studying and application of genetic male sterility in maize. It briefly describes the location, cytological study and marker character of male sterility gene.Some problems and future reseach directions are pointed out in this review.