Effect of High Temperature and Shading during the Developmental Stages of Inflorescence on Flower Bud Abortion in Gymnaster savatieri Kitamura.

The lotus produces flower buds at each node, yet most of them are aborted because of unfavorable environmental changes and the mechanism remains unclear. In this work, we proposed a potential novel pathway for ABA-mediated flower timing control in the lotus, which was explored by combining molecular, genetic, transcriptomic, biochemical, and pharmacologic approaches. We found that the aborting flower buds experienced extensive programmed cell death (PCD). The hormonal changes between the normal and aborting flower buds were dominated by abscisic acid (ABA). Seedlings treated with increasing concentrations of ABA exhibited a differential alleviating effect on flower bud abortion, with a maximal response at 80 μM. Transcriptome analysis further confirmed the changes of ABA content and the occurrence of PCD, and indicated the importance of PCD-related SNF1-related protein kinase 1 (NnSnRK1). The NnSnRK1-silenced lotus seedlings showed stronger flowering ability, with their flower:leaf ratio increased by 40%. When seedlings were treated with ABA, the expression level and protein kinase activity of NnSnRK1 significantly decreased. The phenotype of NnSnRK1-silenced seedlings could also be enhanced by ABA treatment and reversed by tungstate treatment. These results suggested that the decline of ABA content in lotus flower buds released its repression of NnSnRK1, which then initiated flower bud abortion.

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Transcriptomic Analysis of the Anthocyanin Biosynthetic Pathway Reveals the Molecular Mechanism Associated with Purple Color Formation in Dendrobium Nestor

Life ◽

10.3390/life11020113 ◽

2021 ◽

Vol 11 (2) ◽

pp. 113

Author(s):

Xueqiang Cui ◽

Jieling Deng ◽

Changyan Huang ◽

Xuan Tang ◽

Xianmin Li ◽

...

Keyword(s):

Molecular Mechanism ◽

Developmental Stages ◽

Anthocyanin Biosynthesis ◽

Transcriptome Profiling ◽

Flower Color ◽

Flower Bud ◽

Color Formation ◽

Color Development ◽

Purple Coloration ◽

Purple Color

Dendrobium nestor is a famous orchid species in the Orchidaceae family. There is a diversity of flower colorations in the Dendrobium species, but knowledge of the genes involved and molecular mechanism underlying the flower color formation in D. nestor is less studied. Therefore, we performed transcriptome profiling using Illumina sequencing to facilitate thorough studies of the purple color formation in petal samples collected at three developmental stages, namely—flower bud stage (F), half bloom stage (H), and full bloom stage (B) in D. nestor. In addition, we identified key genes and their biosynthetic pathways as well as the transcription factors (TFs) associated with purple flower color formation. We found that the phenylpropanoid–flavonoid–anthocyanin biosynthesis genes such as phenylalanine ammonia lyase, chalcone synthase, anthocyanidin synthase, and UDP-flavonoid glucosyl transferase, were largely up-regulated in the H and B samples as compared to the F samples. This upregulation might partly account for the accumulation of anthocyanins, which confer the purple coloration in these samples. We further identified several differentially expressed genes related to phytohormones such as auxin, ethylene, cytokinins, salicylic acid, brassinosteroid, and abscisic acid, as well as TFs such as MYB and bHLH, which might play important roles in color formation in D. nestor flower. Sturdy upregulation of anthocyanin biosynthetic structural genes might be a potential regulatory mechanism in purple color formation in D. nestor flowers. Several TFs were predicted to regulate the anthocyanin genes through a K-mean clustering analysis. Our study provides valuable resource for future studies to expand our understanding of flower color development mechanisms in D. nestor.

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Floral Scent Emission from Nectaries in the Adaxial Side of the Innermost and Middle Petals in Chimonanthus praecox

International Journal of Molecular Sciences ◽

10.3390/ijms19103278 ◽

2018 ◽

Vol 19 (10) ◽

pp. 3278 ◽

Cited By ~ 6

Author(s):

Zhineng Li ◽

Yingjie Jiang ◽

Daofeng Liu ◽

Jing Ma ◽

Jing Li ◽

...

Keyword(s):

Developmental Stages ◽

Floral Scent ◽

Flower Bud ◽

Adaxial Side ◽

Open Flower ◽

Qrt Pcr ◽

Relative Expression Level ◽

Flower Stage ◽

Chimonanthus Praecox ◽

Deciduous Shrub

Wintersweet (Chimonanthus praecox) is a well-known traditional fragrant plant and a winter-flowering deciduous shrub that originated in China. The five different developmental stages of wintersweet, namely, flower-bud period (FB), displayed petal stage (DP), open flower stage (OF), later blooming period (LB), and wilting period (WP) were studied using a scanning electron microscope (SEM) to determine the distribution characteristics of aroma-emitting nectaries. Results showed that the floral scent was probably emitted from nectaries distributed on the adaxial side of the innermost and middle petals, but almost none on the abaxial side. The nectaries in different developmental periods on the petals differ in numbers, sizes, and characteristics. Although the distribution of nectaries on different rounds of petals showed a diverse pattern at the same developmental periods, that of the nectaries on the same round of petals showed some of regularity. The nectary is concentrated on the adaxial side of the petals, especially in the region near the axis of the lower part of the petals. Based on transcriptional sequence and phylogenetic analysis, we report one nectary development related gene CpCRC (CRABS CLAW), and the other four YABBY family genes, CpFIL (FILAMENTOUS FLOWER), CpYABBY2, CpYABBY5-1, and CpYABBY5-2 in C. praecox (accession no. MH718960-MH718964). Quantitative RT-PCR (qRT-PCR) results showed that the expression characteristics of these YABBY family genes were similar to those of 11 floral scent genes, namely, CpSAMT, CpDMAPP, CpIPP, CpGPPS1, CpGPPS2, CpGPP, CpLIS, CpMYR1, CpFPPS, CpTER3, and CpTER5. The expression levels of these genes were generally higher in the lower part of the petals than in the upper halves in different rounds of petals, the highest being in the innermost petals, but the lowest in the outer petals. Relative expression level of CpFIL, CpCRC, CpYABBY5-1, and CpLIS in the innermost and middle petals in OF stages is significant higher than that of in outer petals, respectively. SEM and qRT-PCR results in C. praecox showed that floral scent emission is related to the distribution of nectaries.

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Heat unit accumulation and inflorescence and fruit development in ‘Ubá’ mango trees grown in Visconde do Rio Branco-MG

Revista Brasileira de Fruticultura ◽

10.1590/0100-29452018491 ◽

2018 ◽

Vol 40 (2) ◽

Author(s):

Lorena Moreira Carvalho Lemos ◽

Luiz Carlos Chamhum Salomão ◽

Dalmo Lopes de Siqueira ◽

Olinto Liparini Pereira ◽

Paulo Roberto Cecon

Keyword(s):

Fruit Development ◽

Fruit Set ◽

Developmental Stages ◽

Mangifera Indica ◽

Developmental Cycle ◽

Flower Bud ◽

Ambient Temperatures ◽

Heat Units ◽

Mango Tree ◽

Apical Bud

Abstract There are little information in the scientific literature on flowering and fruiting of ‘Ubá’ mango trees. These information enables to know the proportion of hermaphrodite flowers in inflorescence, fruit set percentage and developmental stages of the fruit. In this study evaluations on inflorescence and fruit development of the ‘Ubá’ mango tree (Mangifera indica L.) were carried out, as well as the determination of the required number of heat units for full fruit development. Thirty branches whose terminal buds were swollen were selected from five mango trees. With the aid of a camera and a caliper, the panicle and fruit development were evaluated weekly until full fruit development. A digital thermometer was used to record ambient temperatures during fruit development in order to estimate the number of heat units required for complete development of the fruits. Male and hermaphrodite flowers of the panicles were also identified and counted. The developmental cycle of ‘Ubá’ mango from the beginning of apical bud swelling to commercial harvest of the fruit lasted 168 days in 2011 and 154 days in 2012. The number of hermaphrodite flowers and the percentage of fruit set in the inflorescence in 2011 were 32.3 and 0.066%, respectively; and 122.1 and 0.099% in 2012, respectively. There was accumulation of 3,173 heat units from flower bud swelling to full development of the ‘Ubá’ mangoes.

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PEAR FLOWER BUD ABORTION IN SOUTHERN BRAZIL

Acta Horticulturae ◽

10.17660/actahortic.1995.395.20 ◽

1995 ◽

pp. 185-192 ◽

Cited By ~ 6

Author(s):

B.H. Nakasu ◽

F.G. Herter ◽

D.L. Leite ◽

M.C.B. Raseira

Keyword(s):

Southern Brazil ◽

Flower Bud ◽

Flower Bud Abortion

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Hybrid tea-roses under controlled light conditions. I. The effect of the level of irradiance on the growth and development of seedlings.

Netherlands Journal of Agricultural Science ◽

10.18174/njas.v26i1.17117 ◽

1978 ◽

Vol 26 (1) ◽

pp. 119-127

Author(s):

D.P. de Vries ◽

L. Smeets

Keyword(s):

Light Intensity ◽

Leaf Area ◽

Growth And Development ◽

Day Length ◽

Light Conditions ◽

Flower Bud ◽

Juvenile Period ◽

Low Light ◽

Bud Formation ◽

Flower Bud Abortion

As a basis for breeding cvs adapted to flowering in winter light conditions, the growth of hybrid tea rose seedlings under controlled conditions was studied. Irradiance varied from 4-24 W/m2, day length was 8 h, temperature 21 deg C. Like cvs, the seedlings sometimes aborted the flower bud at low light intensity. With increasing irradiances, the following phenomena were observed: the juvenile period of the seedlings shortened; plants were longer at bud formation, at first flowering and at flower bud abortion; leaf area and the number of petals increased. Leaf number was constant at all irradiances. Flowering seedlings were smaller at bud formation, but taller at actual flowering than blind ones. Blind seedlings had fewer leaves with a smaller area. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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Molecular characterization and expression patterns of PsSVP genes reveal distinct roles in flower bud abortion and flowering in tree peony (Paeonia suffruticosa)

Canadian Journal of Plant Science ◽

10.4141/cjps2013-360 ◽

2014 ◽

Vol 94 (7) ◽

pp. 1181-1193 ◽

Cited By ~ 9

Author(s):

Shunli Wang ◽

Jingqi Xue ◽

Noorollah Ahmadi ◽

Patricia Holloway ◽

Fuyong Zhu ◽

...

Keyword(s):

Molecular Characterization ◽

Vegetative Growth ◽

Expression Patterns ◽

Formation Rate ◽

Stage Iii ◽

Flower Formation ◽

Paeonia Suffruticosa ◽

Tree Peony ◽

Flower Bud ◽

Flower Bud Abortion

Wang, S., Xue, J., Ahmadi, N., Holloway, P., Zhu, F., Ren, X. and Zhang, X. 2014. Molecular characterization and expression patterns of PsSVP genes reveal distinct roles in flower bud abortion and flowering in tree peony (Paeonia suffruticosa). Can. J. Plant Sci. 94: 1181–1193. Container culture and flower forcing are used for off-season production of tree peony for the Chinese Spring Festival. Storage of potted tree peony for 10 d at 12°C in a refrigerator before 4°C chilling treatment can help new root growth and promote leaf development. Development from bud swelling to anthesis was divided into nine stages. Some aborted flower buds usually emerge in Stage III. Removal of two to four leaflets in an alternating pattern and applying gibberellic acid 3 (GA3) around the flower bud at Stage III can decrease the flower bud abortion rate and promote flower formation rate. Two MADS-box genes with homology to Arabidopsis SVP, designated PsSVP1 and PsSVP2, which probably caused flower-bud abortion, were isolated by reverse transcription-PCR. Sequence comparison analysis showed that PsSVP was most similar to SVP-like gene in apple. Phylogenetic analysis indicates that PsSVP was evolutionarily close to SVP-like genes from Malus domestica, SVP genes from Cruciferae and SVP-like genes from Vitis vinifera. The qRT-PCR results suggested that expression of PsSVP was high in vegetative growth phase, especially in the leaves of tree peony, and its expression was regulated by GA3. Further analysis showed that more PsSVP transcripted in the aborted flower bud, especially in the buds where leaflets grew well. It was deduced that PsSVP can promote vegetative growth and suppress flowering in tree peony. Thus, it is very important to further investigate PsSVP and decipher the mechanisms of flower-bud abortion to improve forcing culture of tree peony.

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