转基因三倍体毛白杨抗盐试验研究

试验设计4～11g·kg^-18个NaCl浓度梯度，对转PLD／AtNHXI基因抗盐碱三倍体毛白杨进行组培苗抗盐分化试验，设计2～10g·kg^-19个NaCl浓度梯度进行组培苗抗盐生根试验，设计3～12g·kg^-110个NaCl浓度梯度对1年生盆栽苗进行抗盐试验，结果表明：在NaCl浓度达8g·kg^-1时，转基因三倍体毛白杨分化培养37d后，组培苗的叶色、分化芽数及新稍长度开始受到影响，随着NaCl浓度的增大将抑制组培苗分化生长，甚至枯萎死亡；在含NaCl7g·kg“的生根培养基中，培养20d后，虽然叶色没有受到盐太大的影响，但生根和新稍的生长都开始受到抑制，根系明显的减少；在含NaCl7g·kg^-1的土壤条件下，盆栽苗培养32d后，开始表现出盐害症状。

Rapid Propagation of Pteris vittata L.via Tissue Culture

[Objective] The study had developed a means of rapid propagation Pteris vittata L.by tissue culture. The species was a perennial fern belonging to the genus Pteris. [Metbed] The leaf bud of P. vittata collected in field conditions as explantsand the 1/2 MS ＋ 3% sucrose ＋ 0.7% agar as the basic medium were used to screen the medium formula of the phytohormone ratio for callus induction and subculture of P. vittata. [Result] The best medium formula for each step was list below： 1/2 MS ＋ 3% sucrose ＋ 0.7% agar ＋ 0.5 g/L PVP ＋ 0.1 mg/L KT ＋ 0.5 mg/L 2, 4-D for in- ducing the callus from explants; 1/2MS ＋ 3% sucrose ＋ 0.7% agar ＋ 0.5 g/L PVP ＋ 1.0 mg/L KT ＋ 0.01 mg/L 2,4-D for inducing the GGB from callus and the seedlings from GGB. In addition, 1/2 MS ＋ 3% sucrose ＋ 0.7% agar ＋ 0.5 g/L PVP ＋ 0.5 mg/L 2,4-D for the subculture could make the continued proliferation of callus. [Cen- clusioa] This study makes an applicable procedure by the direct use of field materi- als, for propagating P. vittata in a simplified and rapid mode.

Establishment of In Vitro Regeneration System of the Atrichum Mosses

In vitro regeneration systems of Atrichum mosses, Atrichurn undulatum (Hedw.) P. Beauv. and A. undulatum var. minus (Hedw.) Par. were established. After one month, soft, friable and green calli were induced successfully from inoculated protonema of Atrichum mosses on MS medium containing glucose (4%) and 6-BA (0.2-2.0 mg/L). The suitable culture medium for the callus induction and regular subculture was MS medium with 1.0-2.0 mg/L 6-BA and 4% glucose. The calli of Atrichum mosses developed into protonema, when it was transferred to phytohormone-free MS medium with 4% glucose. Meanwhile, the calli developed into erect gametophytes through protonema phase on carbohydrate-free Benecke medium.

Preliminary Study on Callus Differentiation of Hermaphrodite Papaya

With calluses of hermaphrodite papaya as the tested material and MS as the basic medium, the effects of different plant growth regulators and their combinations on adventitious bud induction of calluses and rooting induction of sterile buds were investigated. The results showed that 6-BA and TDZ all showed certain induction effect on callus differentiation of papaya; the induction effect of 6-BA was better than that of TDZ, and the optimum concentration of 6-BA was 0.05 mg/L. GA3 could promote the induction effect of 6-BA for on callus differentiation. The optimum medium combination for inducing the callus differentiation of papaya was MS ＋ 6- BA 0.5 mg/L ＋ GA3 1.0 mg/L. Compared to NAA, IBA was more suitable for inducing the rooting of adventitious buds. The optimum rooting-induction medium combination was MS ＋ IBA 0.3 mg/L.

Research Progress on the Biological Basis of Cereal Pollen Culture

This paper summarizes the physiological and metabolic mechanism of a series of processes in the cereal microspore culture from the angle of plant physiological metabolism, explores the physiological or cytology mechanism of several key processes, including microspore dedifferentiation and callus formation, differentiation and transformation, and sums up the current problems in this field and forecasts the direction of future development.

Effect of Different Hormone Combinations on Somatic Embryogenesis in Cotton Cultivar Xinluzao 33(Gossypium hirsutum L.)

[Objective] This study was conducted to evaluate the efficiency of somatic embryogenesis and plant regeneration for an upland cotton cultivar Xinluzao33 under the induction of different hormone combinations and thus to determine the optimal hormone combination. [Method] Calli of Xinluzao33(Gossypium hirsutum L.) were induced from seedling hypocotyl tissue by a range of DK and BK combinations. Embryogenic calli and embryos were induced on callus-inducing medium(CIM) without any hormones. Callus appearance and quality were compared to determine which medium was the optimal for callus induction. Embryogenesis ratio was calculated to determine which medium was the best for somatic embryogenesis and plant regeneration. [Result] Callus induction rate was 100% in all the 12 hormone combinations.The calli were yellow or kelly, and their texture was loose or soft under low concentrations of DK combinations, green or white, variably compact under high concentrations of DK combinations. The calli induced by BK combinations were kelly or green, covering creamy white substance. The best medium for callus induction was DK6(0.05 mg/L 2, 4-D and 0.10 mg/L KT). Embryogenic calli were successfully induced from all the combinations. The efficiency of embryogenic callus induction,embryogenesis, and plantlet regeneration were significantly different among the 12 combinations. The result showed that the embryogenesis ratio was the highest in BK3 combination(0.50 mg/L IBA and 0.50 mg/L KT), 72.86% of embryogenic calli differentiated into somatic embryos after being cultured on CIM for 80 d, and80.93% of the somatic embryos finally regenerated into plants on SEM(somatic embryo induction medium). [Conclusion] These results indicate that hormone combination BK3(0.50 mg/LIBA and 0.50 mg/L KT) was the best medium for somatic embryogenesis and plant regeneration from Xinluzao33.

香蕉束顶病毒实时荧光PCR检测方法的建立

根据香蕉束顶病毒(Banana bunchy top virus,BBTV)复制酶基因保守序列设计特异性探针及引物,建立了BBTV实时荧光PCR(Taq Man real-time PCR)检测方法。结果显示,所建立的检测方法在检测质粒DNA标准品和发病香蕉植株总DNA时,其灵敏度均比普通PCR高,且与黄瓜花叶病毒(Cucumber mosaic virus,CMV)和香蕉线条病毒(Banana streak virus,BSV)无交叉反应。同浓度样品进行7次重复性试验,各重复扩增结果所得Ct值的变异系数为0.93%,表明建立的荧光定量PCR检测方法重复性好,Ct值保持稳定。利用所建立的方法检测带毒香蕉吸芽繁殖的组培苗中的BBTV,发现BBTV含量随着继代数的增加而增加,并且组培苗顶部叶片中的含量高于其他部位的叶片。