Abstract:Chromosome number and chromosome morphology in Sphagneticola O. Hoffm. and Wollastonia DC. ex Decne., two small genera in Ecliptinae, Heliantheae, Asteraceae, were investigated. The results showed that the karyotype formula were followed as: Sphagneticola calendulacea (L.) Pruski, 2n=50=18m+30sm+2st, S. trilobata (L.) Pruski, 2n=56=24m+28sm+4st, Wollastonia biflora (L.) DC., 2n=30=24m+4sm+2st, and W. montana (Blume) DC., 2n=74=37m+31sm+6st. Based on the results, together with chromosomal data previously reported in Sphagneticola, we postulate the basic chromosome numbers of this genus as x=14 and x=25, rather than x=15. The three species native to the New World tropics in the genus, namely S. brachycarpa (Baker) Pruski, S. gracilis (Richard) Pruski and S. trilobata, may be based on x=14, with S. gracilis being diploid (2n=2x=28), and both S. brachycarpa and S. trilobata tetraploid (2n=4x=56); the only Asian species, S. calendulacea, may be diploid (2n=2x=50) based on x=25. The systematic implication of this chromosome number pattern is worthy of a further study. Chromosomal data do not support the placement of W. montana (x=37) in the genus Wollastonia (x=15).

Abstract:The large-seeded longan (Dimocarpus longan Lour.) cultivar ‘Jiuyuewu’and abortive-seeded cultivars, ‘Minjiao 64-1’,‘Minjiao 64-2’and ‘Baihe’were conducted to inbred or hybrid by artificial pollination, their growth of pollen tube was observed, and the female gametophyte and early zygotic embryo development of two cultivars were investigated by serial paraffin section technique. The results showed that ovule abortion of longan occurred before formation of the mono-nucleated embryo sac, and the abortive rate of ovule in abortive-seeded cultivars were obviously higher than that in large-seeded ones. Pollination rates had difference among different hybrid combinations. Nevertheless, a pollen tube could be observed entering the embryo sac in all combinations tested after pollination 36 to 48 hours. Embryo of abortive-seeded cultivars began to abort 10 days after flowering, which abortion rate was obviously higher than that of large-seeded cultivar. Ovaries did not develop until fertilization occurred. Pistils with abortive ovules did not enlarge 10 days after flowering, and did not develop to abortive-seeded fruits. Early embryo abortion occurring at 10 to 30 days after flowering could be the main factor to form abortive-seeded fruits. The endosperms in abortive-seeded cultivar ‘Baihe’could develop to embryo. The chalazal end cells, synergids and endosperms occurred abnormal development in about 24% ovules of ‘Minjiao 64-1’in ovule development process, which might relate to early embryo abortion.

Abstract:The meiotic process of pollen mother cells in Dianthus chinensis L. was observed by traditional squash method. The results showed that abnormal phenomena, such as bivalent separated in advance, chromosomes scattered outside equatorial plate, lagging chromosomes and chromosome uneven separation, occurred in the process of meiosis. The meiotic process of D. chinensis was generally normal due to abnormality rate at different development stages below 3%. The chromosome number of D. chinensis was 2n=2x=30.

Abstract:The morphology and distribution of calcium oxalate crystals in the vegetative organs of Colocasia esculenta (Araceae) were investigated by hand section under light microscope,and their chemical comstituents were identified by chemical methods. The results showed that the crystals were calcium oxalate crystals which could be divided into two types: needle and cluster crystals. There were three types of rhaphide idioblasts, such as biforines (exist in leaf, petiole and tuber), giant rhaphide bundles (exist in leaf, petiole, tuber and tuber bark), and tubular idioblast with abundant of rhaphides (only exist in adventitious root). The calcium oxalate rhaphides also scatter in tuber and adventitious root. Calcium oxalate druses crystals distribute in leaf, petiole, tuber, tuber bark and adventitious root, and the druses crystals in leaf, petiole and tuber bark were sharper than those in tuber and adventitious root. These calcium oxalate crystals in the vegetative organs of C. esculenta could be used as a defensive mechanism to prevent animal feeding.

Abstract:Zeuxinella Aver., originally described from northern Vietnam, was recently collected from southwestern Guangxi, China. The genus resembles Zeuxine, but differs in its epichile 3-lobed, with 4 close callosities on the disc, mesachie very short, and rostellum undivided.

Abstract:Based on EST sequences from an ethephon-induced latex SSH cDNA library of Hevea brasiliensis, a full-length cDNA encoding AP2/ERF type gene named as HbERFB4-1, was cloned from H. brasiliensis by RACE-PCR. The HbERFB4-1 cDNA has full length of 732 bp with an open reading frame (ORF) of 444 bp, and encodes 147 amino acid residues. No introns were detected in HbERFB4-1gene. The deduced HbERFB4-1 contains an AP2 domain and three NISs, which shows high identity to AP2/ERF in Populus trichocarpa,Ricinus communis,Arabidopsis thaliana and Glycine max, counting for 78%、71%、62% and 55%, respectively. Phyogenetic analysis showed that HbERFB4-1 belonged to the B4 subfamily of ERF family. Semi-quantitative RT-PCR analysis indicated that the transcription of HbERFB4-1 in latex was low, but it was rapidly induced by ethephon, suggesting that HbERFB4-1 is involved in the ethylene signal pathway in latex of H. brasiliensis.

Abstract:The pathogenesis-related protein encoding genes were cloned from sugarcane (Saccharum officenarum) leaves, named as SoSOD、SoCHIT、SoPOD and SoTPS6P. Their expression in S. officenarum leaves infected by Gibberella fujikuroi was studied by real-time quantitative RT-PCR. The results showed that the expression of SoSOD、SoCHIT、SoPOD and SoTPS6P genes could be induced in chewing cane leaves after and the expression levels in leaves of different chewing cane cultivars were different. The expression levels of these genes in cultivars ‘Fengchengzipi’, ‘Baishang’, ‘Fuan’and ‘adila’leaves were higher than those in cultivars ‘Wenlin’, ‘Ninde’and ‘Waigandan’. These indicated that the expression levels of SoSOD、SoCHIT、SoPOD and SoTPS6P associated with the resistance of different chewing cane cultivars to G. fujikuroi.

Abstract:The leaf structure, amaranthin and heat stable protein contents, as well as photosynthetic characteristics were studied in leaves of two cultivars of Amaranthus tricolor L., such as ‘Red flower’and ‘Green leaf’, under the artificial thermal stress of 40℃/35℃ (day/night) for 6 days. The results showed that the amaranthin accumulated greatly in leaves of ‘Red flower’, its content was 1.81 times of that in ‘Green leaf’under high temperature for 6 days. Under light microscope, amaranthin distributed in lower and upper epidermis, vascular bundle of ‘Red flower’, but did not appear in ‘Green leaf’. The palisade tissue structure remained normal in ‘Red flower’, but it partially discontinued and chloroplasts damaged seriously in ‘Green leaf’after 6 days under high temperature stress. Compared with ‘Green leaf’, the chlorophyll and carotenoids contents in ‘Red flower’decreased slightly, the content of heat stable proteins slightly rise, and its light compensation points and saturated light intensity obviously delay. After high temperature stress, the photosynthetic parameters, such as net photosynthesis rate (Pn), intercellular CO₂ concentration (Ci) and stomatal conductance (Gs) in 'Green leaf’were significantly lower than those in ‘Red flower’(P<0.01). It suggested that the accumulation of amaranthin was closely correlated with the thermostability of ‘Red flower’under high temperature, which was benefited to maintained a stable photosynthetic performance.

Abstract:The seeds of transgenic Bt cotton (Gossypium hirsutum L.) 99B were treated with osmotica and salt solution, such as CaCl₂, NaCl, Na₂SO₄ and PEG (6000), the effects of osmotic and salt stresses on the growth and ion allocation in cotton seedlings were studied. The results showed that the growth of transgenic Bt cotton seedlings were inhibited under stresses, in which PEG had the most significant effect, and the inhibition effects of three kinds of salt was in order as CaCl₂>NaCl>Na₂SO₄. Toxicity of Cl^- was greater than SO₄^2- under the same content of Na⁺. Under osmotic stress, the contents of Na⁺ and Cl^- in the roots, stems and leaves increased, but the contents of K⁺, Ca²⁺ and SO₄^2- and K⁺/Na⁺, Ca²⁺/Na⁺and SO₄^2-/Cl^- decreased, and the change range of ion contents in aerial part was greater than those in under-ground part. The effect of PEG on ion contents was the most significant, followed by CaCl₂, and Na₂SO₄ was the weakest. It suggested that the transgenic Bt cotton had low salt tolerance.

Abstract:The growth and physiology characteristics of Phoenix canariensis seedlings were studied cultured on different soil salinity ranged from 1.2 to 14.5. The results showed that the number of new leaves decreased and death leaves increased with soil salinity increment. The chlorophyll content increased under high soil salinity, while chlorophyll a/b increased under low salinity and declined under high salinity more than 5.1. MDA content maintained about 4.30 μmol g^-1 under salinity from 1.2 to 5.1, then increased with soil salinity. The SOD activity increased under low salinity, while decreased rapidly when salinity higher than 10.8. Under salt stress, Na⁺ and Cl^-contents in leaves increased, while K⁺, Ca²⁺ and Mg²⁺ contents and ratio of K⁺/Na⁺ declined. The main reasons of growth decline under salt stress were effective photosynthetic area decrease and destroy of ions balance. These indicated that Phoenix canariensis displayed high resistance to salt stress was suitable to plant widely in coastal districts, which could grow normally under soil salinity lower than 5.1 and only shown damage symptoms above salinity of 10.8.

Abstract:The community characteristics of Michelia chapensis forestthat is located in south subtropical hilly plains in Guangzhou, China were studied. The results showed that there were 70 species belonging 58 genera and 44 families within a transect area of 1600 m². The flora was dominated by tropical and subtropical element, which showed the transition characteristics from tropics to subtropics. The community structure was complex, and the shrub layer was dense with obvious dominant species. There were more individuals with large diameter class, so that the basal area at breast height was very large and up to 66.13 m² hm^-2. Community frequency analysis showed that this community did not agree with the frequency law of Raunkiaer, and the population proportion with the highest frequency was small. The statistical analysis on age structure of dominant species based on transect area showed that the constructive species in the community were declining. Analyses from the regional view in combination with biological characteristic of dominant species showed that the community was the climax type in the location with high stability.

Abstract:Based on the ecological niche space compartmentalization, the nutrition utilization status of the main arbor species of Castanopsis fabri community in different resource spaces in Daiyun Mountain Nature Reserve were studied by using their multidimensional niche breadth and their niche overlap rates. The results showed that the nutrition utilization of different species varied in different resource spaces, i.e. the niche breadths of the same species at different age class were different, and also did the niche breadths of different species at the same age class. There were 33 pairs of species with niche overlap rate ranged from 0.2 to 0.3, which acounted for 27.5% of the total species;and those of 51 pairs over 0.3 acounting for 42.5%. It revealed that the niche overlap rate of dominant populations was comparatively high with similar resources utilization ability, and the competition pattern among them was obvious. The niche overlap rate ranged from 0.042 to 0.424 between C. fabri and other species in tree layer, it indicated the competition to resource utilization between C. fabri and other species was low, and to some extent, it determined the population’s dominant place in the community. According to the classical layered frequency analysis, the C. fabri population belongs to the typical recession type of species, which is consistent with their actual community succession sequence.

Abstract:Based on 3S technology, relationships and muti-scale effects between environmental factors and landscape pattern in the Wuyishan Scenery District was studied by using CCA (Canonical Correspondence Analysis). The results showed that the total eigenvalue of ordination axes increased with upscaling by 9.626, 7.814, 5.708, 4.019, 3.386 and 2.310 in six scales (30 m×30 m、90 m×90 m、150 m×150 m、210 m×210 m、300 m×300 m、450 m×450 m), respectively. The cumulative variance of landscape-environment relationship ranged from 97.3% to 98.8% in the first four ordination axes, and that of the first two ordination axes had an average of 89.4%. Landscape-environment correlation coefficients decreased at first and then increased. The average correlation coefficients between environment factors and landscape pattern were in order as canopy density (0.7989^**) > humus thickness (0.7248^**) > elevation (0.6083^**) > slope (0.6132^**) > longitude (-0.4064^**) > soil thickness (0.3696^**) > latitude (0.0614) > aspect (0.0295). Landscape types in Wuyishan Scenery District could be classified into three types, such as elevation related landscape, including bare land, water body, construction land, and farmland, soil related landscape, including Cunninghamia lanceolata forest, Pinus massoniana forest, broad-leaved forest, and human managed landscape, including Camellia sinensis plantation, economic forest, bamboo forest, shrub and grassland. Therefore, muti-scale effect existed between landscape pattern and environment factors, and the response law of environment factors to ordination axes could be scaling within six scales.

Abstract:A fungal strain of Acremonium sp. SC0105 was obtained from tissue culture of humus collected at Dinghushan, Guangdong Province, China. The EtOH extract of this fungal strain showed antibacterial activity against Staphylococcus aureus. From the solid cultures of this fungus, five compounds were isolated by repeated column chromatography. On the basis of their spectral data, they were identified as gingerglycolipid B (1), gingerglycolipid C (2), D-Mannitol (3), flazine (4), and acremine F (5). Among them, flazine (4) was isolated from fungus of Acremonium genus for the first time.

Abstract:Six compounds were isolated from the EtOH extract of Manihot esculenta (cassava) stems. On the basis of spectral data, they were identified as furan (1), ceplignan (2), indole-3-carboxylic acid (3), 3,9,13-megastigmanetriol (4), amentoflavone (5) and yucalexin P-21 (6). Compounds 1-5 were obtained from cassava for the first time. Antibacterial activity was assayed by paper disk diffusion method, and compounds 1,3,4, and 6 showed inhibitory activity against methicillin-resistant Staphylococcus aureus (MRSA) and S. aureus.

Abstract:Nine known compounds have been isolated from the fruiting bodies of Thelephora terrestris. Their structures were established as (22E,24R)-ergosta-7,22-dien-3β -ol (1), cerevisterol (2), (22E,24R)-ergosta-4,6,8(14),22-tetraen-3-one (3), 24-methylenelanost-8-en-3 β -ol (4), ursolic acid (5), friedelin (6), cerebroside B (7), (2S,3S,4R,2'R)-2-(2'-hydroxydocosanoy-lamino) octadecane-1,3,4-triol (8), and (2S,3S,4R,2'R)-2-(2'-hydroxytricosanoylamino) octadecane-1,3,4-triol (9).

Abstract:Five glycosides were isolated from the seeds of Litchi chinensis Sonn. by means of solvent fractionation and multiple chromatography. On the basis of spectral data, they were identified as (-)-pinoresinol 4-O-β- D-glucopyranoside (1), phenylethyl β- D-glucopyranoside (2), ethyl β- D-glucopyranoside (3), ethyl α- D-glucopyranoside (4) and cytidine (5). They were all isolated from litchi seeds for the first time.

Abstract:The research progresses and prospects of cross breeding of Phalaenopsis were reviewed, including germplasm resources, cross combinations registering, the choice of hybridization parents, heredity characteristics. The problems in cross breeding of Phalaenopsis were discussed. Based on the cross breeding situation of Phalaenopsis in China, it was proposed how to speed up cross breeding and new varieties cultivation of Phalaenopsis.