Isolation of LiLFY1 and Its Expression in Lily (Lilium longiflorum Thunb.)

LFY family genes play a conserved role in regulating flowering. In this study, the cDNA of LiLFY1 was isolated with the strategy of RT-PCR in combination with RACE from lily （Lilium longiflorum Thunb.）. LiLFY1 encodes a LFY transcriptional factor. The alignment analysis of the deduced LiLFY1 protein with other known LFY family proteins indicates that LiLFY1 is highly homologous with rice RFL and maize FLL. The result of Southern hybridization showed that there are two copies of LFY family genes in lily. LiLFY1 is expressed in young flower buds and shoot apical meristem （SAM） but not in roots, shoots, mature leaves, and mature floral organs. The cloned LiLFY1 gene may be applied to genetic engineering aiming for regulating the flowering time in lily.

SIMULTANEOUS DETERMINATION OF VITAMIN B COMPLEX (THIAMINE, RIBOFLAVIN, NIACIN, PYRIDOXINE AND FOLIC ACID) IN FOODS BY HPLC

A high performance liquid chromatographic assay has been developed for the simultaneous determination of five water soluble vitamins:thimine, riboflavin, niacin, pyridoxine and folic acid in cereal products and fresh vegetables. Food samples were hydrolyzed in 0.4 mol/L HCl, autoclaved at 120℃ 15 psi for 20 minutes, using a μ-Bondapak column (3.9×300mm, Waters Co.), a mobile phase of methanol-water (30:70) (0.005 mol/L heptanesulfonic acid) and a flow rate of 1.0 ml/min gave the most satisfactory separation of the five water soluble vitamins. A double channel deteetion was used: four vitamins (B_5, folic acid, B_2, B_1) were detected hy UV spectrophotometry (254 nm) first, pyridoxine (B_6) was detected by fluoromelry (EX 290nm, EM 395 nm) afterwards. Detection limits were 2, 5, 5, 2and 5ng, linear ranges were 5-10ng, 5-50ng, 5-40ng, 5-50ng and 10-50ng for B_1, B_2, B_5, B_6 and folic acid respectively. Recoveries were 92-100%(B_5), 51-52% (folio acid), 103—105% (B_2), 99—100% (B_6) and 91.3—102% (B_1) respectively. In comparison with a reference method and checking with food composition tables, very satisfactory results were obtained by this method.

RANDOM RESPONSES OF A TWO-DEGREE-OF-FREEDOM STRUCTURE WITH STRONGLY NONLINEAR COUPLING AND PARAMETRIC INTERACTION

This paper investigates the random responses of a TDOF structure with strongly nonlinear coupling and parametric vibration. With the nonlinear cou- pling of inertia in the equations of motion of the system being removed by successive elimination, the non-Gaussian moment equation method (NGM) is applied and 69 moment equations are integrated with central cumulative truncation technique. The stochastic central difference-cum-statistical linearization method(SCD-SL) and the digital simulation method(DSM) are also used. A comparison of results by different methods are given and the SCD-SL method is the most efficient method.

SIMULTANEOUS DETERMINATION OF FAT SOLUBLE VITAMINS A, D_3, E AND K_1 IN FORTIFIED MILK POWDERS BY HPLC

A high performance liquid chromatographic method for the simultaneous determination of four fat soluble vitamins: retinol (vitamin A), cholecalciferol(vitamin D), tocopherol(vitamin E) and phylloquinone(vitamin K_1) in fortified milk powders and egg yolk has been developed. The method requires enzymatic hydrolysis of lipid component of the sample as a pretreatment. Several factors which influence the enzymatic hydrolysis were studied-Separation was achieved using μ-Bondapak C-18 column(3.9×300mm), 98% methanol as mobile phase, a double channel detection was selected; vitamins D_3 E_1 K_1 were detected by UV spectrophotometry (265 nm) first, then vitamin A by fluorometry (EX 325nm, EM 480mm). The retention times of vitamin A_1 D_3, E and K_1 4.87, 9.00, 10.58 and 15.45 min respectively. Detection limit were 0.64, 0.25, 0.50 and 0.07 ng; and the recoveries were 90.5%～103.6% 90.0%～95.6%, 91.7%～98.8%, 91.5%～98.6%, respectively. The vitamins A, D_0, E, K_1 contents in foods were determined satisfactorily.

Determination of Physiological and Biochemical Indicators of Brown-Egg Dwarf Layers at Different Ages

[ Objective] To observe biological characteristics of brown-egg dwarf layers. [ Method ] Physiological and biochemical indicators of brown-egg dwarf layers were determined at the age of 20, 40 and 60 weeks, respectively. Fifty-four chickens were detected, nine roosters and nine hens at each age. [Result] As analyzed by ttest and multiple comparisons, during 20 -60 weeks old, the RBC, HGB, MPV, PDW, LYMPH%, TP and CHO showed an increasing trend. However, during this period, the HCT, MCV, RDW, WBC and LYMPH first decreased and then de- clined, while the MCH, MCHC, PLT, PCT, MID, MID%, GRAN, GRAN%, AST, ALB, TG, ALT and GLU changed contrarily. The chickens at different ages had significantly different physiological and biochemical indicators （P 〈 0.05）. The RBC, HCT, HGB, WBC, LYMPH and AST were significantly different between the roosters and hens during 20 -60 weeks old. [ Conclusion] In the brown-egg dwarf layers, the physiological and bi- ochemical indicators vary with aging, and their difference levels also change with aging.

Manufacture and Properties of SiC(p)/AI Composites Made by Squeeze Casting

SiC(p)/Al composites(volume fraction of SiC V_f=30～40％)were manufactured successfully by squeeze casting,and its properties were investigated.The reinforcements distributed homogeneously and bonded tightly with the matrix in the material.Compared with the matrix alloy Grade 6061,the elastic modulus of SiC(p)/6061 composite is increased by 1.17 times,the tensile strength increased by 27％,while the coefficient of thermal expansion is decreased by 51％.

Construction of a Pea Tendril cDNA Library and Sequence Analysis of a Pea Actin cDNA, PEAcl

Actins are ubiquitous to all of the known eukaryotic organisms. Since the firstdiscovery of actins in higher plants by Yen et al. in 1960s, the actin research ofhigher plants has been extensively carried out. It has been shown that the actin is animportant part of cytoskeleton, being involved in many important biological processes,

Transfer of Bt-toxin protein gene into maize by high-velocity microprojectile bombardments and regeneration of transgenic plants

Bt-toxin protein gene was successfully transferred into maize by the microprojectile bombard-ments of cell suspension,embryogenic calli and immature embryos with a Chinese-made particle gun(JQ-700).Although the bombarded embryogenic calli and immature embryos produced less mean transformants per dishthan the cell suspensions,they were the suitable materials for maize transformation because their culture andregeneration have been achieved in most maize cultivars.The evaluation on the resistance of transgenic plantsto corn borer shows the significant difference between them,from highly resistant to susceptible.

Electrochemical wave transmission and rapid coiling movement in tendril of luffa

The tendril of luffa (Luffa officinale),in response to various non-injurious and injuriousstimulations,will first give rise to electrochemical transmission including the action wave,variation wave,andwave complex.It is then followed by rapid coiling movement which appears within 25—30 s after stimulation.The coiling process continues for 10 min or more.When it is over,the tendril begins to uncoil itself.Tendrils pretreated with the narcotic drug,ethyl ether fail to response to stimulation entirely.Specific inhibitorsof microfilament,cytochalasins B and D,and of myosin,N-ethylmaleimide and iodoacetic acid,are both able toprevent the coiling of tendril,without any effect on the electrical wave transmission.Colchicine,known toinhibit microtubule action,is ineffective in preventing coiling.Acetylcholine is able to provoke the tendril coilingdirectly.The effects of drug pretreatments support the proposal that the electrochemical wave transmission elicitedby stimulation is the forerunner for arousing the rapid movement of the sensitive tendril that the actin and myosinare taking part in.Turgor changes in tendril cells are intimately connected with the transmitted and the motoraction of the compact tissues lining along the more sensitive ventral side of the tendril.As the ventral cellsundergo the abrupt contraction and slightly shrink,the dorsal cells become expanded in coiling.Eventually,turgotresumes normal on both sides when uncoiling occurs.

Introducing Bt Gene Into Maize With Ovary Injection

It is reported here that Bt toxin gene has been successfully transferred into maize inbred line by ovary injection for the first time both at home and abroad. One transgenic plant (To) has been confirmed by Southern blotting and PCR test, and 71 progenies (T1) from T0 have been obtained through self-pollination. Of these 71 progenies, seven plants demonstrated positive results in the PCR test; four were used to feed Asian corn borer, and certain effect of insect-resistance was observed. The experiments on the ovary injection in Hainan Province have also been repeated, thus providing new chance to the application of genetic engineering to the maize improvement.

IMPROVEMENT OF THE PURIFICATION OF CHLOROPLAST DNA FROM HIGHER PLANTS

For the study of molecular biology of photosynthesis in higher plants, the isolation and purification of chloroplast DNA (ctDNA)is very important. Among the present methods for isolation of ctDNA from higher plants, the first step is to isolate pure chloroplasts in order to avoid the contamination of nuclear and mitochondrial DNA. Afterwards, the chloroplasts are cleaved to release the ctDNA. For isolation and purification of ctDNA, the methods frequently used are DNaseI method, sucrose density gradient

ISOLATION OF ZEARALENONE FROM SHOOT APICES OF OVERWINTERING WINTER WHEAT

A substance identified to be zearalenone was found in shoot apices of winter wheat seed-lings. The identity of the compound was verified by TLC, HPLC, UV spectrum, MS (EI)and MS/MS (CI) analysis.

Transformation of maize embryogenic calli mediated by ultrasonication and regeneration of fertile transgenic plants

An insecticidal protein gene isolated from Bacillus thuringiensis was transferred into maize by using ultrasonication. The fertile transgenic plants and their progeny were obtained. The Southern hybridization results indi-cated that the foreign gene had integrated into the maize genome. It has been found that the acoustic intensity and the duration of treatment are the important parameters influencing transformation efficiency by ultrasonication. The maxi-mum relative transformation frequency of 34. 1 % was achieved after 30 min of sonication at 0. 5 W/cm2 acoustic inten-sity. With appropriate parameters the ultrasonication ran make a number of micropores formed on the cell surface and minimize the treatment damage to the foreign DNA molecules, thus facilitating the DNA molecules to enter the cells.

A CORRECTION OF SCHRDTER'S TEMPERATURE EQUIVALENCE EQUATION FOR FUNGUS GROWTH

Based on the experimental data of Cohen and Yarwood on growth curves of some hundred fungi, Schr(?)dter worked out a mathematical model, a function named temperature equivalence equation for fungus growth, to describe the growth curves in relation to temperature. Schr(?)dter’s model is valid in theoretical background and

THE MEMBRANE PROTEINS OF LEAF CELL MEMBRANE OF Vicia faba

The membranes of animal cells, especially those of human red cells, have been intensively studied. It has been demonstrated that there is a membrane skeleton on the inside of the red cell membrane. The membrane skeleton is composed of membrane proteins such as spectrin, ankyrin and actin. The presence of a similar membrane skeleton in other animal cells was reported also.

Cloning of 5' regulatory element of bovine β-lactoglobulin gene and its utilization in generation of mammary bioreactors

To obtain a regulatory element for generating mammary bioreactors. a DNA fragment derived from bovine β-lactoglobulin (BLG) gene was cloned, which consisted of a 650-bp 5' flanking sequence, exon Ⅰ, intron Ⅰ and exon Ⅱ. A 661-bp region of the cloned fragment, consisting of the 650-bp 5' flanking sequence and a non-coding sequence of 11 bp downstream of the transcription initiation site, was used as a regulatory element to combine with human growth hormone (hGH) gene to generate a bovine BLG/hGH fusion construct, which was then introduced into cultured primary mammary epithelial cells of goat for transient expression of hGH gene. It was demonstrated that the hGH gene was able to express following hormone induction and the expressed product was able to be secreted into the medium. The bovine BLG/hGH fusion construct was also used to generate transgenic mice by microinjection. Subsequently, five transgenic mice were generated. The hGH in milk by one transgenic female mouse was 420μg/mL, while the content of hGH in serum was 0.051 μg/mL only. This indicated that the cloned regulatory element in this experiment could make the expression of target gene occur almost specifically in mammary gland and the expressed product could be secreted with milk.

CLUSTER ANALYSIS OF THE SPECIES OF Ustilago IN CHINA

The smut fungi are destructive parasites of plants, especially of some important cereal crops. Mycologists have no consensus about the basic criteria for the classification of smut fungi. The genus Ustilago (Pers.) Roussel (1806)is a large genus of around 300 species, which are rather cosmopolitan. However, mycologists have different points of view about the classification of the species under this genus.

A SELECTIVE MEDIUM FOR ISOLATION OF ERWINIA STEWARTII(E. F. SMITH) DYE FROM IMPORTED CORN

A selective medium, designated as nigrosine medium (NM) was devised for the isolation of Erwinia stewartii (E. F. Smith) Dye, the causal agent of Stewart’s wilt, from imported corn seed. The constituents are shown in Table 1.

In vitro GROWTH AND PRODUCTION OF "VEGETATIVE SPORES" OF VA MYCORRHIZAL FUNGUS——Glomus sinensis

The growth of vesicular-arbuscular mycorrhizal(VAM) fungi in pure culture in the absence of host tissue is an important problem which greatly limits the deeper studies on taxonomy, genetics and physiology of this group of fungi and their application in crop produc-