金花茶花药愈伤组织的体细胞减数分裂

金花茶（Ｃａｍｅｌｌｉａｐｅｔｅｌｏｔｉｉ）的小孢子单核期花药，经培养和继代培养６个月后的愈伤组织中，发现有少量体细胞进行减数分裂。在成效第一和第二次分裂中，同源染色体的配对和分离基本正常，最后形成四分体。该愈伤组织经石蜡切片和压片观察，发现其主要由大量的液化细胞和贮藏细胞所组成，此外，还有少部分分生细胞。没有发现进一步的分化。其染色体数目，２ｎ＝３０者占７１．７％，其余则为非整倍体。

Sugarcane Callus Culture and Cytological Characteristics

In order to obtain sugarcane embryogenic calli for transgenosis, the effects of different soaking time of explants, medium, culture conditions and sampling time on sugarcane callus culture were investigated. The results showed that soaking ex- plants with MS liquid medium for 20 min could significantly reduce the browning rate; MS＋3.0 mg/L 2.4-D was appropriate for induction and proliferation of embryo- genic calli; dark condition was suitable for the culture of sugarcane calli; calli differ- entiated from materials collected in August exhibited low browning rate, high callus induction rate and high embryogenic callus induction rate. Calli with different pheno- types were stained, prepared into slides and observed under a microscope to ana- lyze the cytological characteristics. The resultsshowed that milky-white granular em- bryogenic calli had closely arranged cells with large nucleus and exhibited strong differentiation capacity, which were appropriate receptor materials for genetic trans- formation of sugarcane.

Callus Induction and Cell Suspension Culture of Eggplant(Solanum melongena L.)

[Objective] The aim of this article is to establish a cell suspension culture system for eggplant. [Method] Using orthogonal design, appropriate media were screened for callus induction, subculture and cell suspension culture. [Result] The appropriate medium for callus induction was MS supplemented with 0.2 mg/L 6-BA and 0.2 mg/L NAA; the appropriate subculture medium was MS supplemented with0.2 mg/L 6-BA, 0.2 mg/L NAA, and 0.1 mg/L KT; the suitable medium for cell suspension culture was liquid MS medium supplemented with 0.4 mg/L NAA and 0.2mg/L. Cell growth curve was similar to ＂S＂ shape in the above suspension medium.The cell growth included four phases, the initial phase（1-3 d）, the logarithmic phase（3-7 d）, the steady phase（7-8 d）, and the decline phase（8-11 d）. With the increasing culture time, the number of suspension cells increased, and it reached the maximum value at the 7thd, about 3.8 ×105cells/ml. Then the number of cells began to decline rapidly. The cell vigor was the highest at the initial phase. Suspension cells grew best in the liquid MS medium supplemented with NAA（0.4 mg/L）and 6-BA（0.2 mg/L）. The mitotic index reached the maximum, about 4.1% in the above medium, which suggested that this medium was suitable for cell suspension culture of eggplant. [Conclusion] Cell suspension culture system of eggplant provides a significant method for eggplant biotechnology. Genetic transformation and mutants screening can be carried out with this system.

Study on the Browning in Cell Suspension Culture of Taxus cuspidata

[Objective] This study aimed to investigate the browning of T. cuspidata cells in suspension culture and provide the guidance for the cell suspension culture of T. cuspidata. [Method] T. cuspidata callus was used as experimental materials, to explore the effect of different medium, N/P ratio, pH, shaking speed, illumination time and light intensity and other factors on browning of T. cuspidata cells in suspension culture. [Result] Non-browning callus was transferred to 2MB5 medium （pH 7.0） for illumination culture at 22℃ under light intensity of 1 500 lx with shaking speed of 90 r/min for 24 h. Results showed that the cell browning was significantly inhibited. [Conclusion] This study laid the foundation for cell suspension culture of T. cuspidata and had important significance to the large-scale industrial production of paclitaxel.

Somatic embryogenesis in wild relatives of cotton (Gossypium Spp.)

Wild cotton species can contribute a valuable gene pool for agronomically desirable cultivated tetraploid cultivars. In order to exploit diploid cotton a regeneration system is required to achieve transformation based goals. The present studies aimed at optimizing the conditions for regeneration of local varieties as well as wild species of cotton. Different callus induction media were tested with varying concentrations of hormones in which sucrose was used as nutritional source. Different explants (hypo-cotyls, cotyledon, root) were used to check the regeneration of both local cotton plants and wild relatives using T & G medium, BAP medium, CIM medium, EMMS medium, and cell suspension medium. Different stages of embryogenicity such as early torpedo stage, late torpedo stage, heart stage, globular stage and cotyledonary stage were observed in wild relatives of cotton. The results of this study pave the way for establishing future transformation methods.

Optimization of Cell Line Building for Taxus chinensis var. mairei

[Objective] The paper aims to optimize the abduction and domestication conditions of Taxus chinensis var.Mairei callus.[Method] We compared the efficiencies of callus between different explants and investigated the multiplication conditions of callus and suspended cell culture conditions with the buds,young stems and young leaves from T.chinensis var as the explants.[Results] The effect was the best with the bud as the explants; the best way for sterilizing the explants of T.chinensis var mairei was：streptomycin detergent for 2 h ＋ suds for 3 h ＋ 75% alcohol disinfection for 30 s ＋ 10% sodium hypochlorite solution for 25 min ＋ 1‰ mercury chloride for 10 min; the optimum formula of callus subculture was：B5 ＋ 4.0 mg/L NAA ＋ 0.5 mg/L 2,4-D ＋ 0.2 mg/L GA ＋ 0.5 mg/L 6-BA ＋ 2 g/L AC.[Conclusion] This research built the high efficient regeneration system of T.chinensis var.

Cell Viability of Byrsonima intermedia A Juss Calli

Byrsonima intermedia A Juss. is a species with pharmacological properties from the Brazilian Cerrado that shows difficulties related to sexual propagation. Research on cell viability may provide useful information for the selection of cells with embryogenic potential during the callus culture, Within this context, our research is aimed at establishing the cell viability of calli from Byrsonima intermedia leaf segments. The calli went through three subculture phases, of 60 days each, in MS medium with 0.09 M sucrose, 0.6% agar, pH 5.8 and 4.52 laM 2,4-D. The calli were stored in dark conditions and samples were collected every 10 days from each subculture for viability tests with fluorescein 3,6-diacetate （FDA） and 2,3,5-triphenyltetrazolium chloride （TTC）. The staining methods allowed quantifying cell viability in each subculture. The best results from the FDA tests were obtained at 21, 25 and 29 days for the first, second and third subcultures respectively, with 53,86%, 61.88% and 53.73% viable cells. Regarding the TTC test, the largest absorbance values were obtained at 21, 27 and 28 days for the first, second and third subcultures respectively. Fluorescence and spectrophotometry analyses were efficient for determination of cell viability during callus cultivation period.

Development of an Efficient Plant Regeneration System for Pelargonium×Citrosum Vanleenii

[Objective]As a mosquito-repelling ornamental plant,Pelargonium×Citrosum Vanleenii(P.× Citrosum Vanleenii)is hard to be acquired because of its hybrid background,the paper was to a new regeneration system of(P.× Citrosum Vanleenii).[Method] By studying the influence of plant growth regulators(PGRs)on explant type(leaves and petioles),the optimal combinations of PGRs to maximize SELSs(somatic embryo-like structure)and buds were established.[Result]0.2 mg/L NAA+1.0 mg/L BA was best for LS(leaves segments)and 0.2 mg/L NAA + 1.5 mg/L BAs was best for PS(petioles segments).Cultured plantlets were successfully acclimatized in soil where they grew normally without any morphological variation.Although both LS and PS were usable,the leaf was a better explant for induction of embryogenic calli,somatic embryo-like structures and buds.[Conclusion]This work offered a rapid and efficient system for plant regeneration of P.×Citrosum Vanleenii.

Exuberant callus formation misdiagnosed as osteosarcoma:a case report

Reactive lesions of bone and soft tissue can appear alarming on histologic examination because they are often cellular and have atypical cytologic features,such as distinct nucleoli,mild hyperchromasia,and mitotic activity.Reactive lesions of bone and periosteum also produce bone and cartilage matrix,resulting in confusion with osteosarcoma or chondrosarcoma.Careful attention to key cytomorphological features such as the pattern of bone formation,uniform appearance of cells,and absence of atypical mitoses should help identify the reactive nature of a lesion.Correlation with clinical and radiological findings is also imperative to avoid misclassification of the tumor because reactive lesions often arise at sites where osteosarcoma and chondrosarcoma are rare(eg,the hand)and lack aggressive radiological features.Here we present a case of exuberant callus formation after avulsion fracture of tibia in a three year-old Iranian girl which misdiagnosed as osteosarcoma.

Characterization of Pro-embryogenic Calli and Somatic Embryogenesis of Byrsonima intermedia A. Juss.

Byrsonima intermedia A. Juss. is a species from the Brazilian Cerrado that produces edible fruits and, in common with other species from the Byrsonima genus, has pharmacological potential. Previous attempts to propagate the species through conventional methods showed difficulties. Thus, the purpose of this work was to characterize pro-embryogenic masses of Byrsonima intermedia callus, aiming for their in vitro propagation through somatic embryogenesis. Leaf segments from in vitro germinated seedlings were employed as explants for callus production. The calli were then subcultured and exposed to dyes to fulfill their embryogenic potential. Digitalizations of the cytological preparations were made in order to measure the area that was stained by both Aceto-Carmine and Evans-Blue, using image tool software. Somatic embryos were induced after treatments with l-naphthaleneacetic acid （NAA）. The percentages of double-colored areas （by Aceto-Carmine and Evans-Blue） were calculated and the data were analyzed by using the Skott-Knott test （P ≤ 0.05） and, the embryogenic callus, as well as the formation of somatic embryos were analyzed by using the Krsuskal-Wallis rank test （P ≤0.05）. The results show that double coloration is effective at identifying cells showing embryogenic potential. Early callus subculture phases show a larger percentage ofembryogenic area （83%） Somatic embryos were induced by using high auxin level.

In Vitro Regeneration of Commercial Sugarcane （Saccharum spp.） Cultivars in Nigeria

The effect of different concentrations of 6-benzylaminopurine （BA） with or without 0.2 mg/L NAA on in vitro regeneration of sugarcane （Saccharum spp.） cultivars SP726180, B47419, M1176/77 and M2119/88 were evaluated. Leaf base explants were cultured on Murashige and Skoog （MS） basal medium supplemented with 3.0 mg/L 2,4-dichlorophenoxyacetic acid （2,4-D） for 4 weeks. Thereafter, induction of somatic embryogenesis was observed following the transfer of resulting calli to 2,4-D-free medium for another 4 weeks. Regeneration was achieved by transfer of the embryogenic calli to regeneration media fortified with different concentrations of BA ＋ tt-naphthylacetic acid （NAA）. The number, length and vigor of shoots produced in all the genotypes were highest on media supplemented with 1.0 and 1.5 mg/L BA with and without 0.2 mg/L NAA. Among the genotypes tested, B47419 and M1176/77 recorded highest number of shoots, while maximum shoot length and crop vigor was obtained with M1176/77. Induction of callus with 3.0 mg/L 2,4-D and its subsequent incubation on 2,4-D-free media, followed by regeneration on media supplemented with 1.0 or 1.5 mg/L BA with 0.2 mg/L NAA was found to be efficient for in vitro regeneration of the sugarcane genotypes used in this study. This protocol could be applied for micropropagation of other elite genotypes.