为提高紫薇(Lagerstroemia indica L.)嫩枝扦插生根率,调控扦插苗当年开花时间,采用四因素混合正交试验设计L8(4×24),研究扦插基质、穗条长度、插穗留叶方式对红薇、二红紫薇2种紫薇嫩枝扦插生根的影响,并通过施肥调控扦插苗当年开花.结果表明,栽培种、基质配比是影响扦插生根的重要因素,其次是穗条长度和留叶方式,移栽后施用高磷钾肥有助于紫薇当年开花.红薇嫩枝扦插1次成花技术集成:穗条长度13～15 cm+留2片叶+泥炭土:蛭石=1:1组合的25 d生根率达100％,17 d扦插无纺布容器苗移栽后10 d,每7 d施0.1％花多多2号肥料1次,移栽22 d后初花,盛花期从9月25日持续到10月17日,开花率达72.5％.二红紫薇当年生穗条长度13～15 cm+剪叶1/2+泥炭土:蛭石=1:1组合的生根率52.4％,平均根数4.5条,移栽后当年未开花.

林学专业部分学生对林业地位的认识不足、专业认同感不强,"森林培育学"是林学专业的核心课程,具有实施课程思政教育的优势.在"森林培育学"课程教学中通过提升教师思政教学能力、建设思政案例、改革教学方法、创造思政育人环境、改进思政考核方法等途径开展了课程思政教育的建设和实践.将思政元素润物无声地贯穿于"森林培育学"课程教学过程,实现学生在家国情怀、时代使命、专业认同、科学精神、个人素养等方面提升的思政育人效果,实现价值塑造、能力培养和知识传授"三位一体"的育人目标.

以多年生独杆紫薇地栽苗为试材,采用修剪强度和修剪时间双因素随机区组试验设计,随后进行轮次修剪,研究其对紫薇多轮开花的影响,以期为轮次修剪技术调控紫薇花期提供参考依据.结果 表明:修剪强度和修剪时间对紫薇修剪后萌芽和开花均具有极显著性影响,二者组合间具有显著性差异;修剪时间对紫薇修剪后的萌芽期、现蕾期、初花期、盛花期等主要物候期的影响较大;对紫薇进行轮次修剪可让紫薇不间断地有4轮盛花期,花期可持续81 d,与不修剪的紫薇相比可延长51 d,其中以7月19日中度剪梢+8月2日中度剪梢+8月23日对7月19日中度剪梢萌发花枝花后剪花序这种轮次修剪处理组合能获得最佳的4轮开花状态.研究证明,在紫薇生长期采用轮次修剪的方法能有效延长花期,增加紫薇的园林观赏价值.

针对当前高校栽培学课程教学改革中存在的问题,探索了园林树木栽培学系列教材建设与教学改革的有效途径,具体作法包括把"纸质教材+传统PPT教学模式"改进为"新形态教材+MOOC"教学资源形式、设计"三级三提升"混合式教学模式和搭建"三位一体"全方位实践创新平台.对该成果的推广应用取得了很好的成效.

Phyllanthus hainanensis is a shrub that has been used in traditional herbal medicine. It has great pharmaceutical potential for treating diseases such as cancer and diabetes. As a prerequisite for propagation of this species on a large scale, hairy roots in P. hainanensis were induced using Rhizobium rhizogenes and various factors affecting hairy root induction and growth evaluated. Seven factors were tested: (1) type of explant, (2) type of culture medium, (3) duration of pre-culture, (4) R. rhizogenes inoculum cell density, (5) duration of infection, (6) acetosyringone concentration in the culture medium, and (7) duration of incubation. The optimal protocol for hairy root induction and growth was: young shoots, pre-cultured in Y1 for 2 d, inoculated with R. rhizogenes broth with an OD600 of 0.6 for 20 min, and incubated for 3 d. Putative transgenic hairy roots were initially identified by morphology and then confirmed by polymerase chain reaction. Successful and optimal production of hairy roots is a critical prerequisite for industrial scale clonal propagation of P. hainanensis. Being able to cultivate the plant on a large scale will provide rapid and ready supply of the plant materials that can be used in herbal medicine and in scientific and industrial exploitation.

以日本复色矮紫薇(Lagerstroemia indica L.)5年生盆栽苗为试验材料,采用双因素完全随机区组试验设计,研究修剪强度和留芽数量对紫薇二次开花的影响.结果表明,修剪强度对紫薇修剪后萌芽长有极显著影响,轻度和中度剪梢萌芽情况较佳;修剪强度和留芽数量及其组合间对紫薇修剪后花枝长、花序长、整株花序数量均具有极显著影响,轻度剪梢、中度剪梢分别留4芽处理的花序长、小花枝数、整株花序数量指标较高;修剪强度对紫薇修剪后初花期、盛花期、末花期等主要物候期的影响较大,通过修剪能让紫薇二次开花,花期延长55 d.不同的修剪强度和留芽数量均能有效影响紫薇修剪后再次开花的情况.

High planting density of Masson pine (Pinus massoniana) is perceived to have a major impact on timber production as well as understory biodiversity through changed leaf area index (LAI) and reduced understory photosynthetically active radiation (PAR). However, the quantitative relationship between planting density and LAI and understory PAR for Masson pine is unknown. To study the effects of planting density on LAI and understory PAR, we measured LAI and percentage of PAR (PPAR) transmitted through the crown of 15-year-old Masson pine at three planting densities. Total tree LAI varied between different planting densities, ranged from 2.43 to 3.85 m(2)/m(2) at the crown level and from 1.28 to 1.67 m(2)/m(2) at the stand level. Comparing to low planting density, high planting density reduced LAI at the crown level by 37% and PPAR by 49%. As a result, planting density had considerable effects on tree growth. High planting density reduced crown diameters (0.27m and 0.47m smaller than that of trees in medium and low density, respectively) and diameter at breast height (0.55 cm and 1.15 cm smaller than that of trees in medium and low density, respectively), but had no effect on tree height. Thus planting density may be used as a management technique for production of different sized timber for Masson pine. (c) 2019 The Authors. Published by Elsevier B.V.

创新型人才培养对研究生课程教学提出了更高的要求.案例教学是适应这一要求的重要教学方式.以林学与林业专业的主干专业课程“林木遗传改良与良种工程”为对象,探讨了案例教学的必要性,阐述了案例课程建设设计、案例课程建设措施及课程教学的组织实施,案例教学的效果,激发了学生的学习主动性,提升了研究生的科研素质;案例教学的体会:顶层设计总前提,教学团队是保证,案例设计是基础,教学过程是关键,考核手段是补充.

Male sterility of Zinnia elegans is widely used in F1 generation. In order to establish the EST-SSR molecular markers of Zinnia elegans male fertility, provide the scientific foundation for the molecular marker assisted breeding of Zinnia elegans,the EST sequences of Zinnia from NCBI were analyzed,20667 unigenes were obtained to develop new EST-derived SSR markers.Then with 20μL red enzyme PCR reaction, taking the male sterile two-type lines MJ16AB of Zinnia elegans as templates, primers were screened 622 SSRs,whose repeated motifs were not less than 5 times and repeated length greater than 12 bp,were obtained. Among them,the dominant types of the dinucleotide and trinucleotide repeats were AT/TA and CTA/GAT,accounting for 9.5% and 10.6% repectively.5 among 136 pairs of primers could produce stable and expected polymorphism PCR products between fertile pool and sterile pool of Zinnia elegans,they were primers 28,30, 33,69 and ZeM63 respectively.The results indicated that it is a feasible way to develop EST-SSR markers from Zinnia elegans EST,5 polymorphic primers could be used for the establishment of molecular markers of Zinnia elegans male fertility.

以二倍体红薇(H,2n)、三倍体紫薇(Z,3n)、四倍体紫薇(Z,4n)及四倍体银薇(Y,4n)为试材,进行杂交试验,检测紫薇异倍体杂交的亲和性,并采用细胞学倍性鉴定法对杂交子代的倍性进行鉴定和比较.结果显示:不同杂交组合子代的结实特性以及种子的出苗率均存在差异,其中Z(4n)×H(2n)的单果重(0.22 g)、单果种子数(40.1)、千粒重(1.79 g)及出苗率(36.4％)均高于H(2n) ×Y(4n),且差异达到显著水平,表明在二倍体与四倍体的杂交中,四倍体作为母本的亲和性更高;H(2n)×Z(3n)后代倍性主要为非整倍体,占80％以上,其次是2n,占11.8％;Y(4n)×H(2n)后代倍性主要为3n,占50％,其次是非整倍体,占40％;H(2n)×Z(3n)后代中,1株为3n,2株为非整倍体;Y(4n)×H(2n)后代中,6株为3n,3株为非整倍体;H(2n)×Y(4n)后代幼苗中,1株为2n,1株为3n;Z(4n)×Z(4n)后代中,1株为4n;在杂交组合H(2n)×Z(3n)、Y(4n)×H(2n)及H(2n)×Y(4n)后代中还出现三子叶变异的幼苗.

This study used stem segments as explants,and investigated the factors that affected tissue culture and rapid propagation of crape myrtle,including disinfection time,explant harvesting time,and recipe for the primary,secondary and rooting medium.The results suggested that the stems with buds from summer branches were the best among those from spring-,summer-,and autumn-branches.The apical and axillary bud of the current-year summer branch performed well when disinfection in 0.1% HgCl 2 for 4 and 6 min,respectively.The optimized induction and amplification medium for crape myrtle stem was MS + 6-BA 1.0 mg / L + NAA 0.1 mg / L,and the germination rate was 97.6%.After four rounds of culture,the number of adventive buds reached 61.The rooting medium of 1 /2MS + IBA 0.5 mg / L was optimal for plantlet.

To provide theoretical basis for artificial pollination in Lagerstroemia indica L., pollen viability and stigma receptivity were tested and the morphological change of stigma was observed. Pollen viability tested by in vitro culture, stigma receptivity examined by benzidine-H2O2 testing and fruit set estimated by field artificial pollination were analyzed in this study. The maximum pollen viability was observed at 10:00 am one day of anthesis (DA), of which ‘Hong Wei’ (46.2%) was significantly lower than that of ‘Yin Wei’ (56.8%) and ‘Zi Wei’ (62.5%). The stigma receptivity of the three crape myrtle cultivars was sustained for eight days, which was 95.7 to 96.9% at 1 DA to two days after anthesis (DAA), then declined to 75.5 to 79.9% at 3 to 4 DAA and 50.6 to 59.7% at 5 to 6 DAA, and only 29.5% at 7 DAA. Higher stigma receptivity was associated with columnar style, upward stigma, green and wet papillae and copious exudates at stage 1 (1 DA to 2 DAA). Frequencies of fruit set at stage 1 (74.4%) and stage 2 (3 to 4 DAA) (78.9%) were significantly higher than that at stage 3 (5 to 6 DAA) (21.9%). So, selecting pollen at 10:00 am 1 DA and stigma of 1 DA to 4 DAA was a strategy to enhance fruit set in the future artificial hybridizations for crape myrtle. Key words : Lagerstroemia indica L., dimorphic pollen, pollen viability, stigma receptivity, fruit set.

In order to isolate genes related to anther development and understand molecular basis of male sterility, cDNA library of Zinnia elegans was constructed using suppression subtractive hybridization (SSH) approach. 672 different expressed clones were selected from the fertile disk floret buds. PCR results showed that cDNA inserts were ranged from 100 to 750 bp. 303 positive clones screened by dot-blot hybridization were sequenced. 273 out of 303 sequenced clones produced readable sequences; these sequences represent 87 non-repetitive sequences. The homology alignment showed that 76 expressed sequence tags (ESTs) had functional annotations in GenBank, the other 11 ESTs without any homology to the known gene. In addition, 87 ESTs were divided into 17 groups according to MIPS of Arabidopsis thaliana database. Sequence data from the cDNA library have been deposited with the GenBank under the accession numbers GT067016-GT067085. As an important result in this study, 7 genes related to anther development were isolated. Results from semi-quantitative RT-PCR showed 6 genes were expressed only in disk florets of fertile plants compared with that of male sterile plants. These ESTs obtained provide important clues for further isolation and identification of fertility-related genes in Z. elegans.

Plant regeneration of Tagetes patula was achieved from anther explants via adventitious shoot differentiation from callus. The effects of genotype, temperature pretreatment, plant growth regulators, light regimes and sucrose concentration were studied. Eight of ten genotypes tested were successfully regenerated. The highest callus induction rate and regeneration frequency of line 21605 was obtained when inflorescence buds were stored at 4°C for 4 days, and anthers with microspores at the mid to late uninucleate stage were cultured on MS basal medium containing BA (2.2 µM) and NAA (1.82 or 2.7 µM). Frequencies of callus induction and shoot regeneration were 100 and 70.5%, respectively with the whole regeneration procedure completed in 40 days under light. This highly efficient, rapid regeneration system can be applied for both genetic transformation and doubled haploid plant induction.

Nineteen parental lines including five male sterile A-lines (AH002A, AH003A, AH209A, S5001A, J16A) and fourteen restorers (A1-GH, A3, S5, J6, J7N, J7J, J8, J9, J10, J11, J12, J13, J14, J17) were crossed using the North Carolina II statistical method. Studies of combining ability and heritability were conducted on selected parents along with their seventy F1 hybrids for main ornamental traits. Plant height, crown size and length of node had obvious additive genetic effects, high (>0.50) broad sense heritability and high narrow sense heritability (length of node was medium). Pedicel length showed approximately equivalent maternal and paternal additive genetic effects, high broad sense heritability and medium (0.30–0.50) narrow sense heritability. Number of whorls of ray florets across capitulum and number of branches were able to take advantage of heterosis. The relationship between general combining ability and specific combining ability in Zinnia elegans depended on materials and traits. Male sterile two-type line was pivotal in the hybridization breeding of Z. elegans. S5001A, AH002A and A1-GH, A3, J14 which performed high negative GCA effects in PH, PL, LN and type I in PH, PL, NW, LN were ideal female and male parents of potted flowering plants; AH209A, J16A and S5, J10, J17 which displayed positive GCA effects and almost type I in PH, PL, LN were ideal female and male parents of cut flowers, respectively. For potted flowering plants, AH002A×J17, AH209A×A1-GH and S5001A×J6 with high negative SCA effects in PH, PL and LN were the most promising combinations, AH002A×S5, AH003A×A3 and J16A×J6 were the subprime combinations; for cut flowers, AH209A×S5, AH209A×J17 and J16A×J17 with high positive SCA effects in PH, PL and LN were the primary combinations, AH209A×J9 and S5001A×J10 were the secondary combinations.

Eight cross combinations of Zinnia elegans were made using two recessive nuclear male sterile lines crossed with four restorers using the North Carolina Design II statistical method. Heterosis, combining ability and heritability was analysed using 12 horticultural traits and these demonstrated the advantage of heterosis in hybrid breeding of Zinnia elegans. Heterosis served to increase the number of whorls of ray florets across capitulum and the number of branches, and also decreased plant height, crown size, pedicel length and length of node. Thus, six horticultural traits were improved over mid parent and best parent status to fulfill major breeding goals of this herbaceous flower. The traits of plant height, number of whorls of ray florets across capitulum and pedicel length were primarily controlled by paternal additive effects, whereas crown size was mainly controlled by non-additive effects. Number of branches and length of node were affected both by paternal additive effects and non-additive effects. The ratio of general combining ability to specific combining ability indicated the importance of additive genes in the expression of these traits. Among the parental lines, AH003A and restorer A3 were chosen as primary female and male combiners, respectively. AH001A and restorer S5 were chosen as secondary combiners. The cross AH003A × A3 was determined as the most promising combination for producing potted plant characteristics, and AH001A × S5 was the best hybrid obtained in this study for cut flower traits. The analysis of combining ability for the parental lines showed that there was no causal relationship between general combining ability and specific combining ability effects.

The tips of cotyledon-stage seedlings of three crape myrtle cultivars (“Zi Wei”, “Hong Wei” and “Yin Wei”) were treated with colchicine. Various concentrations of colchicine and different treatment durations were tested. Seedlings of “Zi Wei” treated with 0.5% colchicine for 72h and seedlings of “Yin Wei” treated with colchicine (0.2% for 96h, 0.5% for 48h and 0.8% for 72h) demonstrated high rates of mutation; “Hong Wei” showed a slightly lower rate. The highest rate of morphological variation was 54.17% and this was achieved when tips were treated with 0.5% colchicine for 72h. Putative tetraploid plants were identified with morphological and cytological variations, such as larger and thicker leaves, darker green coloration, larger stomata, lower density of stomata across the lower leaf epidermis and increased numbers of chloroplasts per stomata guard cell. Flow cytometric analysis demonstrated that the nuclear DNA content of 15 of these putative tetraploids (of which 7 were “Zi Wei”, 5 were “Yin Wei”, and 3 were “Hong Wei”) was indeed doubled relative to that of control diploid plants. The chromosome number of the tetraploid plants was 2n=4x=96, while that of the control diploid plants was 2n=2x=48. Ornamental characteristics were also enhanced in the tetraploid plants, with increased diameter of the individual flowers and greater basal length of the petals and claws. Pollen diameter and the size of capsules and seeds were also significantly greater than those of diploid plants.

A high frequency shoot regeneration system for ornamental kale [Brassica oleracea L. var. acephala (D.C.) Alef.] was firstly established from seedling cotyledon and hypocotyl explants. The ability of cotyledon and hypocotyl to produce adventitious shoots varied depending upon genotype, seedling age and culture medium. The maximum shoot regeneration frequency was obtained when the explants from cv. Nagoya 4-d-old seedlings were cultured on Murashige and Skoog (MS) medium supplemented with 3 mg dm−3 6-benzylaminopurine (BA) and 0.1 mg dm−3 naphthaleneacetic acid (NAA). The frequency of shoot regeneration was 65.0 % for cotyledons, 76.1 % for hypocotyls; and the number of shoots per explant was 4.3 for cotyledons, 8.2 for hypocotyls. Hypocotyl explants were found to be more responsive for regeneration when compared with cotyledons. Among the 4 cultivars tested, Nagoya showed the best shoot regeneration response. The addition of 3.0 mg dm−3 AgNO3 was beneficial to shoot regeneration. Roots were formed on the base of the shoots when cultured on half-strength MS medium.

The effects of colchicine concentration and treatment time duration on the apical meristems of the seedlings in three species of Lagerstroemia indica have been conducted in this study,and the ploidy level was identified by morphological trait,chromosome number and flow cytometry techniques.The results showed that treated L.indica or L.indica var.alba with 0.5%-0.8% colchicine for 48-96 h lead to a high mutation rate,and the highest mutation rate(up to 54.17%)was achieved in the L.indica by treatment of 0.5% colchicine for 72 h.All the three tested species of L.indica have obtained a number of tetraploidy plants.The choromosome number of mutated plants was 2n=4x=96,while that of the control plants was 2n=2x=48.The tetraploid plants exibited some morphological and cytological variations,including larger and thicker leaves,darker leaf color,larger stomata,fewer stomata per unit area,more chloroplasts in stomata guard cell and longer pollen diameter.The ornamental value of single flower had also been greatly improved by increasing of flower diameter,petals and basal claw length.