Lilies are globally cultivated ornamental flowers and an economic crop, whose flower bud initiation is regulated by a complex interplay of intrinsic factors and external environmental conditions; however, this mechanism remains largely unknown. In the present study, RNA sequencing (RNA-seq) coupled with histological and gene functional data were employed to reveal the differences in flower bud initiation between various lily cultivars. The results exhibited that the floral buds of the O-series 'Brasilia' and 'Hachi' differentiated quickly, the LA -series 'Purple Marble' and the OA-series 'Hotel California' were slower some differentially expressed genes (DEGS) involved in pathways such as photoperiod, gibberellin, age, vernalization, autonomous, and temperature were identified. A flowering transition-related gene, FCA, was identified, and the effectiveness of the virus-induced gene silencing (VIGS) system was validated. The results showed the expression of LtFCA was successfully knocked down using the VIGS system, leading to compromised flower bud initiation in silenced lily plants. This observation underscores a potential correlation between the expression patterns of flowering regulatory genes and the distinct species within the lily series. In conclusion, this research provides a basis for understanding the regulatory mechanisms of flower bud transition in lilies.

The emerging technology of inhibiting polyphenol oxidase (PPO) is crucial for preventing enzymatic browning in food. This study aimed to investigate the effects of 4.5 kJ/m2 ultraviolet (UV)-C radiation and 0.02 mg/mL L-cysteine (L-cys) treatment on the enzyme activity, physico-chemical properties, thermal properties, structure, and molecular microstructure of PPO. UV-C/L-cys decreased PPO activity and had the highest aggregation index and turbidity of PPO. UV-C/L-cys further reduced the denaturation temperature point and increased the denaturation enthalpy of PPO. UV-C/L-cys turned the α-helix to random coil of PPO and destroyed the tertiary structure. This combined treatment aggregated the microstructure of PPO, which led to covering the active center of the enzyme, leading to its inactivation. Molecular docking simulation confirmed that L-cys bound to PPO through hydrogen bonding and ionic contact. This study established a foundation for the application of UV-C radiation and L-cys treatment to control food browning.

Lilium davidii var. willmottiae, known as Lanzhou lily, is a famous edible crop that is mostly distributed in the middle area of Gansu Province in China. In the winter of 2019, symptoms of bulb rot were observed on Lanzhou lilies harvested from Lanzhou, Gansu Province, during storage at the Institute of Grassland, Flowers and Ecology (39°57'55.984" N, 116°20'8.124" E), Beijing Academy of Agriculture and Forestry Sciences, at an incidence of nearly 50%. The decayed bulb (Fig.1a)was washed under tap water and surface disinfested with 75% ethanol for 1 min, followed by 2.5% sodium hypochlorite for 5 min, and washed with sterile distilled water three times. The 5 mm×5 mm tissue pieces from the junction of the diseased part and the healthy part were clipped, placed on potato dextrose agar (PDA) medium and subsequently incubated at 25 °C. Thirteen dominant pure fungal isolates with the same morphological characteristics were obtained by the hyphal-tip method. Three representative isolates LZ-8, LZ-9-2 and LZ-10 were chosen for phylogenetic analyses. The internal transcribed spacer (ITS), translation elongation factor 1-alpha (TEF-1a), and RNA polymerase II second largest subunit (RPB2) sequences were PCR amplified using the primer pairs ITS1/ITS4 (White et al. 1990), EF1-728F/EF1-986R (Carbone and Kohn 1999), and RPB2-5F2/RPB2-7cR (O'Donnell et al. 2022), respectively. BLAST analysis showed that the ITS,TEF-1a, and RPB2 sequences of the isolates LZ-8 (GenBank accession nos. PP422096, PP447248, and PP447251), LZ-9-2 (GenBank accession nos. PP422098, PP447249, and PP447252) and LZ-10 (GenBank accession nos. PP422099, PP447250, and PP447253) had 99.27 to 99.71% identity with multiple GenBank sequences of Trichoderma hamatum, and the three DNA fragments of the three isolates showed 100% sequence identity. A phylogenetic tree based on concatenated sequences of the three genes using maximum -likelihood analyses revealed that the three isolates LZ-8, LZ-9-2 and LZ-10 were in the same clade with T. hamatum strains (Fig.2). One representative isolate, LZ-10, was chosen for morphological studies and test of the pathogenicity. The colony of LZ-10 on PDA appeared white with cotton-shaped aerial hyphae early, which later turned light green to green and formed concentric rings (Fig.1d-1f). At the end of conidiophores, three to six pear-shaped branches were irregularly gathered(Fig.1h). Conidia were ellipsoid with the size of 3.1 to 4.4 × 2.2 to 3.1 µm (n =20) (Fig.1g). These morphological characteristics were consistent with the description of Trichoderma hamatum. (Kamala et al. 2015, Han et al. 2017).To test pathogenicity, healthy bulbs were punctured with disposable sterilized needles and soaked in equal amounts of sterile water and conidial suspension (1×107 conidia/mL) for 30 min respectively. The pathogenicity experiment was repeated three times. After 6 days of inoculation at 25 °C and 80% relative humidity, the surface of the inoculated bulbs produced water-stained spots and mycelium layers(Fig.1b-1c) consistent with the symptoms exhibited by Lilium davidii var. willmottiae bulbs during storage, meanwhile the uninoculated lily bulbs remained symptomless. Trichoderma hamatum was reisolated from the infected bulbs and identified based on morphological and molecular characteristics, fulfilling Koch's postulates. To our knowledge, this is the first report of bulb rot on Lilium davidii var. willmottiae caused by Trichoderma hamatum in China. This study will contribute to a better understanding and controlling of this postharvest disease in Lilium davidii var. willmottiae.

Lanzhou lily bulbs (Lilium davidii var. unicolor) are Chinese traditional edible fruits; however, industrial benefits are limited owing to ineffective post-harvest preservation technology. This study investigated the effect of 4.5 kJ/m2 ultraviolet (UV)-C radiation and 2.0 g/L L-cysteine (L-cys) treatment on storage quality and reactive oxygen species (ROS) metabolism in lily bulbs. The combined UV-C/L-cys treatment inhibited the increase in decay rate, weight loss, ∆E⁎ and reducing sugar content; delayed the decrease of firmness and starch content; retained aromatic volatile compounds; and reduced pungent compounds. UV-C/L-cys treatment reduced H2O2 content, O2 ·- production rate, lipoxygenase activity and malondialdehyde content by maintaining high ROS-scavenging enzymes (superoxide dismutase and catalase) activities and substances (total phenolic and ascorbic acid) levels, thereby protecting mitochondrial structure. Mantel test indicated that post-harvest quality and volatile compounds were closely related to ROS metabolism. Hence, UV-C/L-cys treatment can efficiently delay lily bulb senescence by reducing ROS accumulation during storage.

In June 2021, a disease of stem and leaf rot was observed on lily cultivar 'Tresor' with approximately 20% disease incidence in fields at Huaiyin District (119°04'N, 33°63'E) of Huaian County, Jiangsu Province. The roots and bulbs of symptomatic plants were brown and rotten, with sunken lesions. Symptomatic plants showed short, discolored leaves, and eventually lead to stem wilt and death of the whole plants (Fig. 1A and Fig. 3C). To isolate the pathogen, necrotized plant tissues were surface sterilized with 2% sodium hypochlorite for 2 min followed by 70% ethanol for 30 s and rinsed with sterile water. About 4 mm × 4 mm of diseased tissues were placed on potato dextrose agar (PDA) followed by incubation at 25°C in the dark for 5 days. The pure cultures were obtained by the hyphal-tip method. A total of four fungal isolates with similar colony characteristics were recovered. To determine the identity of the four isolated fungal isolates, genomic DNA was extracted using the method previously described (Khan et al. 2021), the sequences of the internal transcribed spacer (ITS), the translation elongation factor 1α (TEF1) and the RNA polymerase II beta subunit (RPB2) genes were analyzed with primers ITS1/ITS4 (White et al. 1990), EF1/ EF2 (O'Donnell et al. 1998), and 5F2/7cR (Reeb et al. 2004), respectively. The three gene sequences of four isolates showed 99.9 %-100% identities. The531 bp (ITS), 699 bp (TEF1), and 900 bp (RPB2) sequences of a representative isolate (JH-37) were deposited in GenBank with acce. nos. OR195729, OR195041 and OR195040, respectively. A phylogenetic tree was constructed using the concatenated three gene sequences of JH-37 and that of the related Fusarium species based on Maximum Likelihood (Fig.2). JH-37 was grouped together with the F. armeniacum strain CBS 485.94 (AB587001, GQ915501, GQ915485), and shared 99.9 % concatenated sequence identity. The three gene sequences of the strain JH-37 shared 100%, 99.85%, 99.89% identity to F. armeniacum strain CBS 485.94 using MEGA 7 software (Kuma et al. 2016) analysis, and with 94%, 95% and 100% coverage by BLAST analysis. The colony of JH-37 on PDA at 25°C for 5 days was white with yellow-brown pigmentation in the center (Fig. 1B-C). From 10-day-old cultures grown on Spezieller Nahrstoffarmer agar (SNA), macroconidia (n = 50) were falcate, slender, curved dorsiventrally, tapering towards both ends, 3 to 4 septate, and measured 24.2 to 50.0 × 2.6 to 4.2 μm. The microconidia (n = 50) were straight or slightly curved, septate 0 to 2, and measured 6.8 to 20.0× 2.1 to 3.7 μm (Fig.1D-F). These morphological characteristics were consistent with Fusarium spp. (Leslie and Summerell 2006). A pathogenicity test of JH-37 was performed on potted lily ('Tresor') under greenhouse conditions. Healthy lily bulbs were selected and one bulb was sown in soil of each pot. Inoculation was performed 60 days after sowing. Bulbs of the lily plants were wounded with needles and inoculated with 5 mL of conidia suspension (1×107 conidia/mL) in the soil around bulb or an equal amount of sterilized water as a control. This experiment had three replicates. After 15 days of inoculation, typical symptoms of bulb rotten, and leaf wilt, similar to the original field symptoms, appeared on the inoculated plants but not on the controls (Fig.3). The same fungus was reisolated from the diseased plants, as identified based on morphology and molecular evidence, which confirmed the Koch's postulate. To our knowledge, this is the first report that F. armeniacum caused Fusarium wilt on Lilium spp. in China. Further, our result could help to develop effective disease management strategies against lily wilt disease.

Grain development is a crucial determinant of yield and quality in bread wheat (Triticum aestivum L.). However, the regulatory mechanisms underlying wheat grain development remain elusive. Here we report how TaMADS29 interacts with TaNF-YB1 to synergistically regulate early grain development in bread wheat. The tamads29 mutants generated by CRISPR/Cas9 exhibited severe grain filling deficiency, coupled with excessive accumulation of reactive oxygen species (ROS) and abnormal programmed cell death that occurred in early developing grains, while overexpression of TaMADS29 increased grain width and 1,000-kernel weight. Further analysis revealed that TaMADS29 interacted directly with TaNF-YB1; null mutation in TaNF-YB1 caused grain developmental deficiency similar to tamads29 mutants. The regulatory complex composed of TaMADS29 and TaNF-YB1 exercises its possible function that inhibits the excessive accumulation of ROS by regulating the genes involved in chloroplast development and photosynthesis in early developing wheat grains and prevents nucellar projection degradation and endosperm cell death, facilitating transportation of nutrients into the endosperm and wholly filling of developing grains. Collectively, our work not only discloses the molecular mechanism of MADS-box and NF-Y TFs in facilitating bread wheat grain development, but also indicates that caryopsis chloroplast might be a central regulator of grain development rather than merely a photosynthesis organelle. More importantly, our work offers an innovative way to breed high-yield wheat cultivars by controlling the ROS level in developing grains.

Lily (Lilium spp.) is a popular ornamental plant. Traditional genetic transformation methods have low efficiency in lily, thus development of a high-efficiency genetic transformation system is important. In this study, a novel transient transformation method involving pollen magnetofection was established and optimized pollen viability, and exogenous gene expression in magnetofected pollen and that of different germplasm were assessed. The highest germination percentage of Lilium regale pollen was 85.73% in medium containing 100 g/L sucrose, 61.5 mg/L H3BO3, and 91.5 mg/L CaCl2. A 1:4 ratio of nanomagnetic beads to DNA plasmid and transformation time of 0.5 h realized the highest transformation efficiency (88.32%). The GFP activity in transformed pollen averaged 69.66%, while that of the control pollen was 0.00%. In contrast to the control, transgenic seedlings obtained by pollination with magnetofected pollen showed strong positive GUS activity with 56.34% transformation efficiency. Among the lily germplasm tested, 'Sweet Surrender' and L. leucanthum had the highest transformation efficiency (85.80% and 54.47%), whereas L. davidii var. willmottiae was not successfully transformed. Transformation efficiency was positively correlated with pollen equatorial diameter and negatively correlated with polar axis/equatorial diameter ratio. The results suggest that pollen magnetofection-mediated transformation can be applied in Lilium but might have species or cultivar specificity.

研究不同浓度的化学诱变剂 EMS处理对百合干种子及经过沙藏种子萌发的影响,筛选适宜的诱变浓度和诱变时间.利用化学诱变剂 EMS对岷江百合的自交种子进行诱变处理,设置 3 个处理时间(2h,4h,8 h)和 4 个 EMS浓度(0,0.4％,0.8％,1.2％)对岷江百合自交种子进行诱变处理.结果表明,干种子在 0.4％,4 h时相对成活率达 65.38％,接近半致死剂量,而沙藏处理的种子在 0.4％,2 h时相对成活率达 62.3％,接近半致死剂量.因此,0.4％浓度的EMS,处理4h为 EMS处理百合干种子的较适宜方式,0.4％浓度的 EMS,处理 2h为 EMS处理沙藏种子较适宜方式.

WRINKLED1 (WRI1), an APETALA2 (AP2) transcription factor (TF), critically regulates the processes related to fatty acid synthesis, storage oil accumulation, and seed development in plants. However, the WRI1 genes remain unknown in allohexaploid bread wheat (Triticum aestivum L.). In this study, based on the sequence of Arabidopsis AtWRI1, two TaWRI1Ls genes of bread wheat, TaWRI1L1 and TaWRI1L2, were cloned. TaWRI1L2 was closely related to monocotyledons and clustered in one subgroup with AtWRI1, while TaWRI1L1 was clustered in another subgroup with AtWRI3 and AtWRI4. Both were expressed highly in the developmental grain, subcellular localized in the nucleus, and showed transcriptional activation activity. TaWRI1L2, rather than TaWRI1L1, promoted oil body accumulation and significantly increased triglyceride (TAG) content in tobacco leaves. Overexpression of TaWRI1L2 compensated for the functional loss of AtWRI1 in an Arabidopsis mutant and restored the wild-type phenotypes of seed shape, generation, and fatty acid synthesis and accumulation. Knockout of TaWRI1L2 reduced grain size, 1000 grain weight, and grain fatty acid synthesis in bread wheat. Conclusively, TaWRI1L2, rather than TaWRI1L1, was the key transcriptional factor in the regulation of grain fatty acid synthesis in bread wheat. This study lays a foundation for gene regulation and genetic manipulation of fatty acid synthesis in wheat genetic breeding programs.

A number of potential genes and pathways involved in tepal trichome development were identified in a natural lily mutant by transcriptome analysis and were confirmed with trichome and trichomeless species. Trichome is a specialized structure found on the surface of the plant with an important function in survival against abiotic and biotic stress. It is also an important economic trait in crop breeding. Extensive research has investigated the foliar trichome in model plants (Arabidopsis and tomato). However, the developmental mechanism of tepal trichome remains elusive. Lilium pumilum is an edible ornamental bulb and a good breeding parent possessing cold and salt-alkali resistance. Here, we found a natural mutant of Lilium pumilum grown on a highland whose tepals are covered by trichomes. Our data indicate that trichomes of the mutant are multicellular and branchless. Notably, stomata are also developed on the tepal of the mutant as well, suggesting there may be a correlation between trichome and stomata regulation. Furthermore, we isolated 27 differentially expressed genes (DEGs) by comparing the transcriptome profiling between the natural mutant and the wild type. These 27 genes belong to 4 groups: epidermal cell cycle and division, trichome morphogenesis, stress response, and transcription factors. Quantitative real-time PCR in Lilium pumilum (natural mutant and the wild type) and other lily species (Lilium leichtlinii var. maximowiczii/trichome; Lilium davidii var. willmottiae/, trichomeless) confirmed the validation of RNA-seq data and identified several trichome-related genes.

Paenibacillus polymyxa is a plant growth-promoting rhizobacterium that has immense potential to be used as an environmentally friendly replacement of chemical fertilizers and pesticides. In the present study, Paenibacillus polymyxa SK1 was isolated from bulbs of Lilium lancifolium . The isolated endophytic strain showed antifungal activities against important plant pathogens like Botryosphaeria dothidea , Fusarium oxysporum , Botrytis cinerea , and Fusarium fujikuroi . The highest percentage of growth inhibition, i.e., 66.67 ± 2.23%, was observed for SK1 against Botryosphaeria dothidea followed by 61.19 ± 3.12%, 60.71 ± 3.53%, and 55.54 ± 2.89% against Botrytis cinerea , Fusarium fujikuroi , and Fusarium oxysporum , respectively. The metabolite profiling of ethyl acetate fraction was assessed through the UHPLC-LTQ-IT-MS/MS analysis, and putative identification was done with the aid of the GNPS molecular networking workflow. A total of 29 compounds were putatively identified which included dipeptides, tripeptides, cyclopeptides (cyclo-(Leu-Leu), cyclo(Pro-Phe)), 2-heptyl-3-hydroxy 4-quinolone, 6-oxocativic acid, anhydrobrazilic acid, 1-(5-methoxy-1H-indol-3-yl)-2-piperidin-1-ylethane-1,2-dione, octadecenoic acid, pyochelin, 15-hydroxy-5Z,8Z,11Z, 13E-eicosatetraenoic acid, (Z)-7-[(2R,3S)-3-[(2Z,5E)-Undeca-2,5-dienyl]oxiran-2-yl]hept-5-enoic acid, arginylasparagine, cholic acid, sphinganine, elaidic acid, gossypin, L-carnosine, tetrodotoxin, and ursodiol. The high antifungal activity of SK1 might be attributed to the presence of these bioactive compounds. The isolated strain SK1 showed plant growth-promoting traits such as the production of organic acids, ACC deaminase, indole-3-acetic acid (IAA), siderophores, nitrogen fixation, and phosphate solubilization. IAA production was strongly correlated with the application of exogenous tryptophan concentrations in the medium. Furthermore, inoculation of SK1 enhanced plant growth of two Lilium varieties, Tresor and White Heaven, under greenhouse condition. In the light of these findings, the P. polymyxa SK1 may be utilized as a source of plant growth promotion and disease control in sustainable agriculture.

百合是多年生草本植物,花色丰富,花型优美,在切花、盆栽观赏和城市美化等方面都有着很大用途。本研究以两个百合品种Lilium ‘Tiger Babies’和Lilium ‘Whistler’为试验材料,在种球从萌发出约5 cm新芽到生长至开花期喷施一定浓度的GA及PAC,观察其对植株生长的影响。结果表明GA处理后‘Tiger Babies’的株高、节间长较对照明显增加,而‘Whistler’的株高与节间长与对照相比没有明显变化。PAC处理对两个百合品种植株的生长发育都具有明显的抑制作用,对‘Tiger Babies’的抑制效果更为明显。经过GA和PAC处理,两个百合品种的种球鲜重和种球大小均有所轻微的影响。以两个百合品种不同生长时期的叶片的cDNA为模板,对赤霉素合成关键基因GA20OX、GA3OX和GA2OX基因进行了qRT-PCR分析。结果表明GA处理后,不同生长时期,两个百合品种中这3个关键基因表达量均小于CK,但‘Tiger Babies’中其表达量与CK相比差异较大,明显低于对照;而‘Whistler’中其表达量与CK相比差异不显著。PAC处理后,3种基因的表达量均显著高于CK,与GA处理后的结果相反。以上结果表明两个百合品种对外源喷施GA的响应有所不同外,存在一定差异。本研究为进一步研究植物生长调节剂在百合株型上的应用提供理论依据。

In the present study, a new strain of Bacillus stratosphericus LW-03 was isolated from the bulbs of Lilium wardii. The isolated endophytic strain LW-03 exhibited excellent antifungal activity against common plant pathogens, such as Fusarium oxysporum, Botryosphaeria dothidea, Botrytis cinerea, and Fusarium fujikuroi. The growth inhibition percentage of Botryosphaeria dothidea was 74.56 ± 2.35%, which was the highest, followed by Botrytis cinerea, Fusarium fujikuroi, and Fusarium oxysporum were 71.91 ± 2.87%, 69.54 ± 2.73%, and 65.13 ± 1.91%, respectively. The ethyl acetate fraction revealed a number of bioactive compounds and several of which were putatively identified as antimicrobial agents, such as 4-hydroxy-2-nonenylquinoline N-oxide, sphingosine ceramides like cer(d18:0/16:0(2OH)), cer(d18:0/16:0), and cer(d18:1/0:0), di-peptides, tri-peptide, cyclopeptides [cyclo(D-Trp-L-Pro)], [cyclo (Pro-Phe)], dehydroabietylamine, oxazepam, 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine like compound (PC(0:0/20:4), phosphatidylethanolamine (PE(18:1/0:0)), 3-Hydroxyoctadecanoic acid, 7.alpha.,27-Dihydroxycholesterol, N-Acetyl-d-mannosamine, p-Hydroxyphenyllactic acid, Phytomonic acid, and 2-undecenyl-quinoloin-4 (1H). The LW-03 strain exhibits multiple plant growth-promoting traits, including the production of organic acids, ACC deaminase, indole-3-acetic acid (IAA), siderophores, and nitrogen fixation activity. The beneficial effects of the endophytic strain LW-03 on the growth of two lily varieties were further evaluated under greenhouse conditions. Our results revealed plant growth-promoting activity in inoculated plants relative to non-inoculated control plants. The broad-spectrum antifungal activity and multiple plant growth-promoting properties of Bacillus stratosphericus LW-03 make it an important player in the development of biological fertilizers and sustainable agricultural biological control strategies.

In the present study, a new strain ofBacillus stratosphericusLW-03 was isolated from the bulbs ofLilium wardii.The isolated endophytic strain LW-03 exhibited excellent antifungal activity against common plant pathogens, such asFusarium oxysporum, Botryosphaeria dothidea,Botrytis cinerea,andFusarium fujikuroi. The growth inhibition percentage ofBotryosphaeria dothideawas 74.56 +/- 2.35%, which was the highest, followed byBotrytis cinerea,Fusarium fujikuroi, andFusarium oxysporumwere 71.91 +/- 2.87%, 69.54 +/- 2.73%, and 65.13 +/- 1.91%, respectively. The ethyl acetate fraction revealed a number of bioactive compounds and several of which were putatively identified as antimicrobial agents, such as 4-hydroxy-2-nonenylquinolineN-oxide, sphingosine ceramides like cer(d18:0/16:0(2OH)), cer(d18:0/16:0), and cer(d18:1/0:0), di-peptides, tri-peptide, cyclopeptides [cyclo(D-Trp-L-Pro)], [cyclo (Pro-Phe)], dehydroabietylamine, oxazepam, 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine like compound (PC(0:0/20:4), phosphatidylethanolamine (PE(18:1/0:0)), 3-Hydroxyoctadecanoic acid, 7.alpha.,27-Dihydroxycholesterol,N-Acetyl-d-mannosamine, p-Hydroxyphenyllactic acid, Phytomonic acid, and 2-undecenyl-quinoloin-4 (1H). The LW-03 strain exhibits multiple plant growth-promoting traits, including the production of organic acids, ACC deaminase, indole-3-acetic acid (IAA), siderophores, and nitrogen fixation activity. The beneficial effects of the endophytic strain LW-03 on the growth of two lily varieties were further evaluated under greenhouse conditions. Our results revealed plant growth-promoting activity in inoculated plants relative to non-inoculated control plants. The broad-spectrum antifungal activity and multiple plant growth-promoting properties ofBacillus stratosphericusLW-03 make it an important player in the development of biological fertilizers and sustainable agricultural biological control strategies.

Bacillus velezensis is an important plant growth-promoting rhizobacterium with immense potential in agriculture development. In the present study, Bacillus velezensis Lle-9 was isolated from the bulbs of Lilium leucanthum. The isolated strain showed antifungal activities against plant pathogens like Botryosphaeria dothidea, Fusarium oxysporum, Botrytis cinerea and Fusarium fujikuroi. The highest percentage of growth inhibition i.e., 68.56 +/- 2.35% was observed against Fusarium oxysporum followed by 63.12 +/- 2.83%, 61.67 +/- 3.39% and 55.82 +/- 2.76% against Botrytis cinerea, Botryosphaeria dothidea, and Fusarium fujikuroi, respectively. The ethyl acetate fraction revealed a number of bioactive compounds and several were identified as antimicrobial agents such as diketopiperazines, cyclo-peptides, linear peptides, latrunculin A, 5a-hydroxy-6-ketocholesterol, (R)-S- lactoylglutathione, triamterene, rubiadin, moxifloxacin, 9- hydroxy-5Z,7E,11Z, 14Z-eicosatetraenoic acid, D-erythro-C18-Sphingosine, citrinin, and 2-arachidonoyllysophosphatidylcholine. The presence of these antimicrobial compounds in the bacterial culture might have contributed to the antifungal activities of the isolated B. velezensis Lle-9. The strain showed plant growth-promoting traits such as production of organic acids, ACC deaminase, indole-3-acetic acid (IAA), siderophores, and nitrogen fixation and phosphate solubilization. IAA production was accelerated with application of exogenous tryptophan concentrations in the medium. Further, the lily plants upon inoculation with Lle-9 exhibited improved vegetative growth, more flowering shoots and longer roots than control plants under greenhouse condition. The isolated B. velezensis strain Lle-9 possessed broad-spectrum antifungal activities and multiple plant growth-promoting traits and thus may play an important role in promoting sustainable agriculture. This strain could be developed and applied in field experiments in order to promote plant growth and control disease pathogens.

Notholirion bulbuliferum a precious endangered species in China, it has a long history of growth and high ornamental and edible value. In this study, we reported a complete chloroplast genome of N. bulbuliferum, in which the whole genome is 153,019 bp in length, and includes one large single copy region of 70,585 bp, one small single copy region of 17,527 bp, and a pair of inverted repeat region of 26,530 bp. It contains 130 genes, comprising 84 protein-coding genes, 36 transfer RNA, and eight rRNA genes. The overall AT content of the chloroplast genome is 62.9%. In the maximum-likelihood and phylogenetic analysis with the reported chloroplast genomes of Notholirion, it showed that N. bulbuliferum and Notholirion macrophyllum get a high support rate (ML (BS) =100%) and become sister groups. It indicates that the study on the complete chloroplast genome of N. bulbuliferum is more closely related to Cardiocrinum than related to Lilium.

在赤霉素(GA)信号传导过程中,有一类起着负调控作用的蛋白——DELLA蛋白,是GRAS家族的亚家族,因其N端含有DELLA结构域而命名.该蛋白对种子萌发、茎的伸长、下胚轴伸长以及花发育等起着重要的调控作用.本研究主要讲述了DELLA蛋白如何参与多种信号传导,分析了模式植物拟南芥中5种DELLA蛋白对植物生长发育的作用,分别介绍了DELLA蛋白的保守结构域及其作用,总结了目前已知DELLA蛋白的克隆及表达情况,最后对今后DELLA蛋白的研究进行展望,以期更好地揭示DELLA蛋白的调控机制.

园林古树组织培养过程中,外植体接种的真菌污染问题非常严重.为能够找到有效的灭菌方式和抑菌剂,我们分离、纯化了组培过程中污染的菌种,并对这些真菌的rDNA-ITS基因序列进行扩增、序列比对,结合形态学方法快速鉴定出污染菌种8个,并使用制霉菌素对鉴定出的8个真菌进行了抑菌实验,结果显示35 mg/L的制霉菌素可以对4个真菌起到抑制作用,浓度升高到70 mg/L可以有效地抑制6个霉菌,但对其余2个菌株没有效果.本研究结果为组织培养中出现的真菌污染防治提供了理论参考依据.

The amount of unsaturated fatty acids in corn oil is up to 80％,but the level of linoleic acid is only about 0.4％～1.2％.To increase the content of linolenic acid in corn oil,a bifunctional △12,△15-Desaturase (AcD12) from A canthamoeba castellanii was used in this research.According to the maize preference codon,we optimized and synthesized A cD12 gene and constructed an efficient expression vector pBAC 106 which contain EPSP gene and anthocyanin synthesis transcription regulation factors gene as visual selection marker gene,and then transformed maize immature embryos via agrobacterium mediated transformation.PCR identification of T0 generation convinced that T-DNA containing EPSP and AcD12 genes had been integrated into the maize genome,and positive activity of EPSP protein tested by strip verified the expression of foreign EPSP gene after the screening by anthocyanin visual selection and herbicide resistance experiment of T1 generation.The analysis of fatty acid composition of transgenic plants showed that,compared with the inbred line Jing501,linolenic acid content in leaves increased in 20％～50％,and inversely,oleic acid and linoleic acid were decreased in 10％～20％.By contrast,in seeds,three types of unsaturated fatty acid are greatly improved.Among them,the content oflinoleic acid increased mostly,was 50％ ～200％,followed by oleic acid and linolenic acid,rose in 50％～ 120％ and 40％～100％,respectively.This study therefore demonstrates that the bifunctional desaturase A cD12 gene was significantly effective in improving the components of corn fatty acids and increasing the amount of linoleic acid in corn oil.