Abstract:Vascular bundles of pedicel in flower of Orchidantha chinensis are scattered withinthe vascular region, but those just beneath the locule are arranged into an outer ringconsisted of large bundles and a central region with dispersed small bundles. The bundlesfrom the outer ring enter to the ovary wall and those from the central region extend to theaxis and become placental bundles which fade away gradually in prolongation. Thecarpellary dorsal bundles (cdbs), the accompanying bundles of the dorsals (abds) and theparietal bundles of the ovary wall could be easily distinguished. Three carpellary dorsalbundles finally enter the style and the stigma via prolongation. The abds, which are largebundles and each of which is adjacent to one carpel1ary dorsal bundle, separately extendinto the three stamens of the outer whorl of androecium. Two abaxial parietal bundles runupwards into the two stamens of inner whorl, while the adaxial one, accompanying theloss of the sixth stamen, enters the median of the labellum. The rest of bundles in ovarywa1l extend into prolongation and branch outwards in swelling part of the prolongation toform the outer ring of bundles, which finally run into three sepals and the remains incentral part arrange in a heart6haped ring. Abaxial bundles in convex end of heart6hapedring separate into two parts and enter to two lateral petals respectively, and the adaxialbundles in concave end of the ring firstly arrange in two rows with the large bundles inouter row and the small ones in inner row but finally become one row and along with theadaxial parietal bundle enter into labellum. It is worth to point out that this kind oflabellum, which is not only a member of corolla but also contains the bundle of the sixthlost stamen, is distinctly different from the cucullatum of Marantaceae and the labeIla inCannaceae, Zingiberaceae and Costaceae, which are only derived fr0m stadrinodes. Basingon the comparison of the origin and structure of the vascular system in androecium ofZingiberales, except Strelitziaceae- because no information could be found in this family,the authors make a prelidrinary suggestion that among the seven fadrilies of Zingiberales,Lowiaceae dright be more close to Musaceae.

Abstract:Microspore development and pollen gendnation in vivo in predeveloped embryorice (PDER) were observed using light and scanning electron microscope. The results showedthat the procedure of ndcrospore development in PDER was the same as that inconventional rice strains, in which mature pollen grains were filled with starch grains. Whenflowering, only part of mature pollen could gerndnate well and get into stigmatic tissue byshort tube, and most of them behaved abnormally: (1) Pollen did not gendnate, butexpel1ed mass of pollen content from the gerndnal aperture. (2) Pollen tube was very small.(3) Pollen tube swelled or broken outside or inside the stigma. (4) Pollen tube entered thestigma and then got out of it. (5) Pollen tube crawled (twisted) at the stigmatic surface. (6)Pollen tube was coated with pollen content. (7) Pollen tube growth direction was reverseinside the stigma. These abnormal phenomena were discussed.

Abstract:The female gametophyte development and process of embryogenesis in DoritisPulcherrima Lindl. were observed. The results indicate that the ovule is of anatropous formWith 2 integuments and one layered nucellus epidetris around the megaspore mother cell,the mature embryo sac consists of 8 cuclei and its formation is conformed to the Alliumtype. The interval between pollination and fertilization is about 50 days, and the normaldouble fertilization has been observed. During the development of the embryo, thesuspensor is composed of 5-6 cells. However, the endosperm nuclei and suspensor are alldegenerated in mature seeds. The embryo in mature seeds is just an undifferentiatedglobular mass with 100-120 cells and the seed coat having only one4ayer cells.

Abstract:This paper is the first part of the study on the system and evolution ofgenus Themeda Forsskal. The nomenclature of Themeda Forsskal, Anthistiria Linn. f. andrelatives were reviewed. The legitimate name Themeda published by Peter Forsskal andseveral synonyrns were listed. Genera Themeda and Anthistiria being exadrined and correctedwere transferred into 10 genera, viz. Themeda Forssk. (70 binom. & 33 spp.), ExothecaAnderss. (1 binom. & 1 sp.), HyParrhenia Anderss, ex Fourn. (13 binom. & 7 spp.),ISeilema Anderss. (7 binom & 3 spp), Hyperthelia W. D. Clayton(1 binom. & 1 sp),Germainia Ba1ans. & Poitr. (2 binom. & 1 sp.), Pseudanthistiria (Hack.) Hook. f (1 binom.& 1 sp.), Tristachya Nees (1 binom. & 1 sp.), CymbOPogon Spreng (1 binom. & 1 sp.),Elymandra Stapf (1 binom. & 1 sp.). Four dubious specific names are presented. Historicalstudy on the systematics of Themeda and allied studies were briefly reviewed. The problemsof evolutionary trend and systernatic treatment have been proposed.

Abstract:Based on the study of natural thinning process in plant populations beingdescribed by predecessors, the authors induced a theoretical model describing the wholedensity change process combined with self-adaptive and general model (SGM), ie.1nN=a1n2S+b1nS+c, where N and S represent population density and mean basal areaper plant, and a, b and c are parameters. It was found that the groWth process ofplants shown in the model is a kind of the Gompertz Curve. Meantime, the authorsproposed a tree density effect model in the stand that can be used in different siteconditions and growth stages. The model is described as N=exp (0.0462994H0.00299305 In2S-1.221487H0.01501599lnS+ 6.253176H0.189734), which is very well proved by observed data fromCastanopsis kawakamii population density, and which is very useful in practice and willprovide a scientific basis for forest management.

Abstract:According to the wide-ranging data on geographical distribution of Gordoniaacuminata, several indexes widely used for the study of vegetationedimate interaction wereapplied. These indexes induded Kira's warndh index and coldness index, Xu's humidityindex, Penman's formula, Thornthwaite's potential evapotranspiration and moisture index,Holdridge's life zone classification system index, and other single climate indexes. Therelationship between the distribution of G. acuminata and dimatic hydrothermal conditionhad been analysed, and the Kira's water-temperature indexes for the upper, lower andnorth lindts of the vertical distribution of G acuminata were discussed. The principalcomponent analysis showed that relative effects of climatic hydrothermal indexes on thedistribution of G acuminata were in the order thermal factor>precipitation factor>accumulated suhshine time>re1ative hunddity. The potential changes of G. acominatadistribution area under elevated CO2 concentration were predicted by .using Holdridge'sindex of life zone classification system and gas circulati0n model's conclusion.

Abstract:The characteristics of phototropism in maize coleoptiles were studied by insertinga ndca piece into coleoptile and using HPLC analysis. The results showed that ndca piececould not stop phototropic movement of maize coleoptiles, though it could prevent thetranslocation of auxin. The coleoptile could bend to grow sindlarly to phototropism whenits one side was injured by a razor blade. Bending growth of the coleoptiles was alsofound when a piece of agar containing injurant which was extracted from injuredcoleoptile, was placed on unilateral side of coleoptile with tip excised HPLC analysisindicated that the inhibiting substance produced during the induction by blue light or bymechanical iaiury was 6methoxy-2-benzoxazolinone (MB).

Abstract:Diatom assemblages on the diatometers were collected from 9 sampling sites ofthe Pearl River at Guangzhou section. Twentydriur genera with 170 diatom taxa wereidentified. Amng them, there were 8 eusaprobic, 84 eurysaprobic and 78 casually saprobictaxa. Conunnity sindlarity cluster analysis showed that the connnnity composition wasmost similar among sites at Yuancun (st3), Xinzao (st8) and shalu0cun (st10) situated atthe middle of Guangzhou section, the commnity sindlarity being reduced gradually at theupper or lower reaches of the river. The diatom assemblage index (DAIpo) values indicatedthat Lianhuashan (st5) and Dasheng (st12) were least polluted which belonged tothe goligosaprobic type, while Huangsha (st2) was most seriously pol1uted and was ofacoosaprobic type- As a site for comparision, Yagang (st1) was also slightly affectedwith pollution, indicating the axiligosaprogic character. The polution of the remaining siteswere between axiligosaprobic and gasesosaprobic. DAIpo had a good negative correlationWith bio1ogical oxygen demand (BOD5) (r=O.86). River pollution index raPId) values ofthe front raPId=56.42) and rear channels (RPId=56.26) of the Guangzhou sectionindicated that the water in these two channels were polluted at a ndddle level.

Abstract:Catalase activity in cucumber leaves increased by 49.65% after the seedlings weresprayed with 100 mg L-1 deltamethrin for 2 days. Deltamethrin of 150 mg L-1 increased thecontents of protein, DNA and RNA by 33.25%, 15.39% and 11.49%, respectively.However, high deltamethrin concentration(500 mg L-1) decreased the catalase aCtivity by6.94%, and decreased the contents of protein, DNA and RNA by 10.22%, 9.85% and16.20%, respectively. No effect of deltamethrin on in vitro catalase activity was found. Theeffects of deltamethrin on protein content and catalase activity in cucumber leaves could bepartially inhibited by cycloheximide. The possible mechanism of the effect of deltamethrinon catalase activity was discussed.

Abstract:Changes of leaf relative water content(RWC), stomatal conductance and levels ofendogenous hormones were investigated in seedling leaves of Wheat cultivars with differentdroughtecsistance under different drought stress conditions. The results showed that therewas a stronger positive linear correlation between the stomatal conductance and the ratioof cytokinins to ABA (CTKs/ABA), while a weaker correlation was observed betweenstomatal conductance and leaf RWC, indicating the stomatal conductance was controlled byCTKs/ABA, not by the leaf RWC. The changes of CTKs/ABA in leaves ndght be used asan indicator to estimate the droughtecsistant ability among wheat cultivars underthe different drought stress conditions. It can be done as follows' the averageCTKs/ABA value in leaves of the more resistant cultivar was higher than the less resistantone or sensitive one, indicating that the former had a higher ratio of promotive hormones,so that it could keep stronger vitality during drought stress, @ the more resistant cultivarshowed a negative quadratic correlation between its leaf CTKs/ABA and drought treatmentdays, while the less resistant one showed a negative linear correlation, indicating the formerhad a higher buffer ability for stress resistance; the decline of CTKs/ABA value inmature leaf (the second leaf) of the more resistant cultivar was faster than that inyoung leaf (the third leaf), while the opposed trend was found in sensitive one, thisimplied that a mechanism of material transport from mature leaves to young leaves ndghtoperate obviously in drought resistant cultivars for self Trotective regulations.

Abstract:Genetic analyses were conducted fot fat content of indicajmpnica hybrid rice byusing genetic medels with genotype x environment interaCtions for seed traits. The resultsindicated that the fat content in rice was mainly controlied simultaneously by seed directadditive and matemal additive effects, with the former predominating. Genotype x environmentinteractions expressed mainly as dommancex environment (including direct dondnance xenvironment and maternal dondnance x environment) and cytoplasm x environmentinteractions- Direct and matemal heritabilities were highly significant. The potential valuesof parehtal lines for the improvement of fat content were discussed in respeet to predictedvalues of genetic effects.

Abstract:Crossing between a white seed coat cultivar White Coat No.1 and three red seedcoat cultivars, Yueyou 116, Shanyou 71 and Quanhua 10, which were main cultivars usedin Fujian Province, were made in order to breed high yield cultivar with white seed coatand to understand the genetics of white seed coat. The seed coat in F, was all red. In F2the segregating ratio of red to white coat in plants conformed with the segregation lawof 15: 1. Among the F3 strains derived from the F2 plantS with red seed coat, 4 to 15strains showed that the ratio of red to white was 3:1, therefore, it was inferred thatthe white seed colour was directed by two recessive genes. The white character did notlinked with yielding traits. Genetic ability of main econodric traits was in order' podnumber per plant>mature pod weight and biological yield>mature pod number.Several stable combination varieties with excellent comprehensive traitS were selected fromFa, F' and F5 strains. Two high yielding varieties were taken part in regional testing fornew peanut variaties in Fujian Province.

Abstract:A new sweet constituent named strogin was isolated from water extract ofStaurogyne mergunsis leaves. On the basis of spectroscopic analysis (UV, IR, GLC, HANR,13C-NMR, 2D-NMR and MS) and investigations of the derivatives, the structure waselucidated as 3-OOocylopyranosyl-(1→2)-gOglucuronopyranosy1-3g, 21g, 22g, 23, 29pentahydroxyolean-12edne-21v`2, 3, 4O4riacetyl)4whanmoside.

Abstract:In this paper, the fatty acid components of the seed oil of PolygaIa fallax wasanalysed and identified by means of GC and GC/MS. These fatty acids (%) were found tobe capric 0.3, lauric 0.3, myristic 0.1, palndtic 1.9, stearic 2.3, arachidic 2.6, oleic 3.8,llreicosenoic 88.5, and an unidentified comP0nent 0.2. It is reported for the first time inplant of Polygalaceae family with a high content of 11-reicosenoic acid.