DEGENERATED LEMMA (DEL) Is a New Allele of OsRDR6 That Regulates Lemma Development and Affects Rice Grain Yield

Abstract The lemma and palea are floral organ structures unique to grasses, and their development affects grain size. However, information on the molecular mechanism of lemma development is limited. In this study, we investigated a rice spikelet mutant, degenerated lemma (del), which developed florets with a slightly degenerated or rod-like lemma. The results indicate that the mutation of the DEL gene interfered with lemma development. In addition, del also showed a significant reduction in grain length and width, seed setting rate, and 1000-grain weight, which led to a reduction in yield. The results indicate that the mutation of the DEL gene further affects rice grain yield. Map-based cloning shows a single-nucleotide substitution from T to A within Os01g0527600/DEL, causing an amino acid mutation of Leu-34 to His-34 in the del mutant. DEL is an allele of OsRDR6, encoding the RNA-dependent RNA polymerase 6, and is highly expressed in the spikelet. RT-qPCR results show that the expression of some floral organ identity genes was changed, which indicates that the DEL gene regulates lemma development by modulating the expression of these genes. The present results suggest that DEL plays an important role in lemma development and rice grain yield.

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SLL1-ZH Regulates Spikelets Architecture and Grain Yield in Rice

Agriculture ◽

10.3390/agriculture11111162 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1162

Author(s):

Lianping Sun ◽

Jingxin Wang ◽

Xiaoxia Wen ◽

Zequn Peng ◽

Daibo Chen ◽

...

Keyword(s):

Grain Yield ◽

Morphological Analysis ◽

Floral Organ ◽

Rice Grain ◽

Related Factors ◽

Single Nucleotide ◽

Floral Organs ◽

Rice Mutant ◽

Organ Identity ◽

Yield Formation

The spikelet developmental processes that control structure and floral organ identity play critical roles in rice grain yield formation. In this study, we characterized a novel rice mutant, SLL1-ZH, which exhibits a variety of defective agronomic characters, including semi-dwarf, rolling leaf, deformed panicles, and reduced grains production. Morphological analysis also revealed that the SLL1-ZH mutant shows numerous defects of floral organs, such as cracked glumes, hooked and thin lemmas, shrunken but thickened paleas, an indeterminate number of stamens and stigmas, and heterotopic ovaries. Map-based cloning identified a single nucleotide substitution (C to G) in the first exon of LOC_Os09g23200 that is responsible for the SLL1-ZH phenotype. In addition, qPCR analysis showed a significant change in the relative expression of SLL1-ZH in the mutant during inflorescence differentiation and in the different floral organs. Transcription of rice floral organ development-related factors also changed significantly in the mutant. Therefore, our results suggested that SLL1-ZH plays a great role in plant growth, spikelet development, and grain yield in rice.

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Contrasting Evolutionary Forces in theArabidopsis thalianaFloral Developmental Pathway

Genetics ◽

10.1093/genetics/160.4.1641 ◽

2002 ◽

Vol 160 (4) ◽

pp. 1641-1650 ◽

Cited By ~ 10

Author(s):

Kenneth M Olsen ◽

Andrew Womack ◽

Ashley R Garrett ◽

Jane I Suddith ◽

Michael D Purugganan

Keyword(s):

Floral Organ ◽

Regulatory Genes ◽

Coding Region ◽

Developmental Pathway ◽

Evolutionary Forces ◽

Coding Regions ◽

Organ Identity ◽

Meristem Identity ◽

Floral Organ Identity Genes ◽

Population Genetic Analyses

AbstractThe floral developmental pathway in Arabidopsis thaliana is composed of several interacting regulatory genes, including the inflorescence architecture gene TERMINAL FLOWER1 (TFL1), the floral meristem identity genes LEAFY (LFY), APETALA1 (AP1), and CAULIFLOWER (CAL), and the floral organ identity genes APETALA3 (AP3) and PISTILLATA (PI). Molecular population genetic analyses of these different genes indicate that the coding regions of AP3 and PI, as well as AP1 and CAL, share similar levels and patterns of nucleotide diversity. In contrast, the coding regions of TFL1 and LFY display a significant reduction in nucleotide variation, suggesting that these sequences have been subjected to a recent adaptive sweep. Moreover, the promoter of TFL1, unlike its coding region, displays high levels of diversity organized into two distinct haplogroups that appear to be maintained by selection. These results suggest that patterns of molecular evoution differ among regulatory genes in this developmental pathway, with the earlier acting genes exhibiting evidence of adaptive evolution.

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Temporal Relationship between the Transcription of Two Arabidopsis MADS Box Genes and the Floral Organ Identity Genes

The Plant Cell ◽

10.2307/3870174 ◽

1995 ◽

Vol 7 (6) ◽

pp. 721 ◽

Cited By ~ 2

Author(s):

Beth Savidge ◽

Steven D. Rounsley ◽

Martin F. Yanofsky

Keyword(s):

Temporal Relationship ◽

Floral Organ ◽

Mads Box ◽

Mads Box Genes ◽

Floral Organ Identity ◽

Organ Identity ◽

Floral Organ Identity Genes

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Phytoplasma-Induced Floral Abnormalities in Catharanthus roseus Are Associated with Phytoplasma Accumulation and Transcript Repression of Floral Organ Identity Genes

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-06-11-0176 ◽

2011 ◽

Vol 24 (12) ◽

pp. 1502-1512 ◽

Cited By ~ 20

Author(s):

Yi-Ting Su ◽

Jen-Chih Chen ◽

Chan-Pin Lin

Keyword(s):

Plant Pathogens ◽

Chalcone Synthase ◽

Floral Development ◽

Transcript Abundance ◽

Floral Organ ◽

Organ Identity ◽

Leaf Yellowing ◽

Or Gene ◽

Highly Correlated ◽

Floral Organ Identity Genes

Floral symptoms caused by phytoplasma largely resemble floral reversion in other plants. Periwinkle leaf yellowing (PLY) phytoplasma and peanut witches'-broom (PnWB) phytoplasma caused different degrees of floral abnormalities on infected periwinkle plants. The PLY phytoplasma-infected plants exhibited floral discoloration, virescence, small flowers, and only occasionally full floral reversion. In contrast, PnWB phytoplasma frequently induced complete floral reversion and resulted in a witches'-broom symptom from the floral reversion. Although different degrees of floral symptoms were induced by these two phytoplasmas, the morphological disorders were similar to those of other plants carrying SEPALLATA mutations or gene silencing. Here, we compared expression levels of organ-identity-related genes and pigmentation genes during floral symptom development. Accumulation of phytoplasmas in malformed flowers and their closely surrounding leaves was also compared. In infected plants, transcript abundance of all examined organ identity genes and pigmentation genes was suppressed. Indeed, CrSEP3, a SEPALLALA3 ortholog, showed the greatest suppression among genes examined. Of the pigmentation genes, transcript reduction of chalcone synthase was most highly correlated with the loss in floral pigmentation. Floral symptom severities were associated with the accumulation of either phytoplasmas. Interestingly, both phytoplasmas accumulated to higher levels in malformed flowers than in their surrounding leaves. Many plant pathogens manipulate host plant development to their advantage. It is intriguing to see whether phytoplasmas alter floral development to increase their population.

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APETALA2 negatively regulates multiple floral organ identity genes in Arabidopsis by recruiting the co-repressor TOPLESS and the histone deacetylase HDA19

Development ◽

10.1242/dev.085407 ◽

2012 ◽

Vol 139 (22) ◽

pp. 4180-4190 ◽

Cited By ~ 155

Author(s):

N. T. Krogan ◽

K. Hogan ◽

J. A. Long

Keyword(s):

Histone Deacetylase ◽

Floral Organ ◽

Floral Organ Identity ◽

Organ Identity ◽

Floral Organ Identity Genes

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Biofortification of Rice Grain as Affected by Different Doses of Zinc Fertilization

Asian Soil Research Journal ◽

10.9734/asrj/2020/v3i130062 ◽

2020 ◽

pp. 1-6

Author(s):

Kamrun Nahar ◽

M. Jahiruddin ◽

M. Rafiqul Islam ◽

Soyema Khatun ◽

M. Roknuzzaman ◽

...

Keyword(s):

Grain Yield ◽

Grain Protein Content ◽

Control Treatment ◽

Rice Grain ◽

Rice Varieties ◽

Crop Varieties ◽

Zinc Fertilization ◽

Zn Concentration ◽

1000 Grain Weight ◽

Different Doses

The experiment was conducted in the research farm at Bangladesh Agricultural University (BAU) to investigate the zinc biofortification ability of rice grain at different doses of zinc fertilization. In this experiment two rice varieties (BRRI dhan28 and Binadhan-16) and five doses (0, 1.5, 3.0, 4.5 and 6.0 kg ha-1) of zinc fertilization were used following split-plot design with three replications. Except 1000-grain weight and plant height, all other plant characters viz., tillers hill-1, panicle length and grains panicle-1 were significantly influenced by zinc fertilization. The treatment receiving Zn at 4.5 kg ha-1 (Zn 4.5) produced the highest grain yield (7.70 t ha-1) in BRRI dhan28 which was statistically similar with the yield obtained with Zn 3.0 treatments. The zinc control treatment (Zn 0) produced the lowest grain yield in both varieties. The concentrations of N, Zn and Fe were significantly and positively influenced by the Zn treatments. The crop varieties did not differ significantly in respect of N and Fe concentrations, but the grain Zn concentration was considerably higher in BINA dhan16 than in BRRI dhan28. The grain N content as well as grain protein content linearly increased with the rates of Zn application. Thus, application of Zn at the rate of 6.0 kg ha-1 demonstrated the highest Zn fortification in both varieties but maximum zinc fortification was observed in Binadhan-16 (24.1 µg g-1) in rice grain which was 12.2% higher over control treatment.

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Mutations in the PERIANTHIA gene of Arabidopsis specifically alter floral organ number and initiation pattern

Development ◽

10.1242/dev.122.4.1261 ◽

1996 ◽

Vol 122 (4) ◽

pp. 1261-1269 ◽

Cited By ~ 10

Author(s):

M.P. Running ◽

E.M. Meyerowitz

Keyword(s):

Floral Organ ◽

Floral Meristem ◽

Wild Type ◽

Organ Identity ◽

The Family ◽

Dividing Cells ◽

Meristem Identity ◽

Plant Families ◽

Open Question ◽

Floral Organ Identity Genes

An open question in developmental biology is how groups of dividing cells can generate specific numbers of segments or organs. We describe the phenotypic effects of mutations in PERIANTHIA, a gene specifically required for floral organ patterning in Arabidopsis thaliana. Most wild-type Arabidopsis flowers have 4 sepals, 4 petals, 6 stamens, and 2 carpels. Flowers of perianthia mutant plants most commonly show a pentamerous pattern of 5 sepals, 5 petals 5 stamens, and 2 carpels. This pattern is characteristic of flowers in a number of plant families, but not in the family Brassicaceae, which includes Arabidopsis. Unlike previously described mutations affecting floral organ number, perianthia does not appear to affect apical or floral meristem sizes, nor is any other aspect of vegetative or floral development severely affected. Floral organs in perianthia arise in a regular, stereotypical pattern similar to that in distantly related species with pentamerous flowers. Genetic analysis shows that PERIANTHIA acts downstream of the floral meristem identity genes and independently of the floral meristem size and floral organ identity genes in establishing floral organ initiation patterns. Thus PERIANTHIA acts in a previously unidentified process required for organ patterning in Arabidopsis flowers.

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