C4 rice: a challenge for plant phenomics

There is now strong evidence that yield potential in rice (Oryza sativa L.) is becoming limited by ‘source’ capacity, i.e. photosynthetic capacity or efficiency, and hence the ability to fill the large number of grain ‘sinks’ produced in modern varieties. One solution to this problem is to introduce a more efficient, higher capacity photosynthetic mechanism to rice, the C4 pathway. A major challenge is identifying and engineering the genes necessary to install C4 photosynthesis in rice. Recently, an international research consortium was established to achieve this aim. Central to the aims of this project is phenotyping large populations of rice and sorghum (Sorghum bicolor L.) mutants for ‘C4-ness’ to identify C3 plants that have acquired C4 characteristics or revertant C4 plants that have lost them. This paper describes a variety of plant phenomics approaches to identify these plants and the genes responsible, based on our detailed physiological knowledge of C4 photosynthesis. Strategies to asses the physiological effects of the installation of components of the C4 pathway in rice are also presented.

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LEAF ANATOMY CHARACTERIZATION OF FOUR Apochloa SPECIES: A C3 GENUS RELATED TO EVOLUTION OF C4 PATHWAY IN GRASSES

Acta Biológica Colombiana ◽

10.15446/abc.v26n1.83228 ◽

2020 ◽

Vol 26 (1) ◽

pp. 12-18

Author(s):

Ane Marcela das Chagas Mendonça ◽

Pedro Lage Viana ◽

João Paulo Rodrigues Alves Delfino Barbosa

Keyword(s):

Leaf Anatomy ◽

C4 Photosynthesis ◽

Water Status ◽

Bundle Sheath ◽

C3 Plants ◽

Plant Water ◽

Kranz Anatomy ◽

C4 Pathway ◽

Photosynthesis Pathway

Leaf anatomy characteristics provide important evidences about the transition between C3 and C4 pathways. The C4 photosynthesis pathway allowed to reduce the C3 photorespiratory rate, concentrating CO2 around the Rubisco site and using structures and machinery already presented in C3 plants. In monocots, it is observed a high number of C4 lineages, most of them phylogenetically related to C3 groups. The genus Apochloa (C3), subtribe Arthropogoninae, is related to two C4 genera Coleataenia and Cyphonanthus. The aim of this study was to evaluate four Apochloa species in order to establish anatomical characteristics related to the evolution of C4 pathway in this group. By means of transverse sections fully expanded leaves of A. euprepes, A. lorea, A. molinioides, and A. poliophylla were collected and the characteristics of the mesophyll (M) and bundle sheath (BS) cells were determined. These species showed a rustic Kranz anatomy with enlarged and radial arranged BS cells, which have few organelles organized in a centrifugal position. Although the modifications of BS cells are probably related to the maintenance of plant water status, we also discuss the evolution for the establishment of C4 photosynthesis in the related C4 genera.

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Modelling metabolic evolution on phenotypic fitness landscapes: a case study on C4 photosynthesis

Biochemical Society Transactions ◽

10.1042/bst20150148 ◽

2015 ◽

Vol 43 (6) ◽

pp. 1172-1176 ◽

Cited By ~ 4

Author(s):

David Heckmann

Keyword(s):

Structural Changes ◽

Crop Yields ◽

C4 Photosynthesis ◽

Fitness Landscape ◽

Fitness Landscapes ◽

C3 Plants ◽

Metabolic Systems ◽

C4 Pathway ◽

Evolutionary Trajectories ◽

Phenotypic Fitness

How did the complex metabolic systems we observe today evolve through adaptive evolution? The fitness landscape is the theoretical framework to answer this question. Since experimental data on natural fitness landscapes is scarce, computational models are a valuable tool to predict landscape topologies and evolutionary trajectories. Careful assumptions about the genetic and phenotypic features of the system under study can simplify the design of such models significantly. The analysis of C4 photosynthesis evolution provides an example for accurate predictions based on the phenotypic fitness landscape of a complex metabolic trait. The C4 pathway evolved multiple times from the ancestral C3 pathway and models predict a smooth ‘Mount Fuji’ landscape accordingly. The modelled phenotypic landscape implies evolutionary trajectories that agree with data on modern intermediate species, indicating that evolution can be predicted based on the phenotypic fitness landscape. Future directions will have to include structural changes of metabolic fitness landscape structure with changing environments. This will not only answer important evolutionary questions about reversibility of metabolic traits, but also suggest strategies to increase crop yields by engineering the C4 pathway into C3 plants.

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Evolutionary transition from C3 to C4 photosynthesis and the route to C4 rice

Biologia ◽

10.2478/s11756-013-0191-5 ◽

2013 ◽

Vol 68 (4) ◽

Cited By ~ 2

Author(s):

Zheng Liu ◽

Ning Sun ◽

Shangjun Yang ◽

Yanhong Zhao ◽

Xiaoqin Wang ◽

...

Keyword(s):

C4 Photosynthesis ◽

C3 Plants ◽

Hydraulic Systems ◽

Leaf Architecture ◽

Evolutionary Trajectory ◽

Bisphosphate Carboxylase ◽

Bundle Sheath Cells ◽

C4 Pathway ◽

C4 Evolution ◽

C4 Enzymes

AbstractCompared with C3 plants, C4 plants possess a mechanism to concentrate CO2 around the ribulose-1,5-bisphosphate carboxylase/oxygenase in chloroplasts of bundle sheath cells so that the carboxylation reaction work at a much more efficient rate, thereby substantially eliminate the oxygenation reaction and the resulting photorespiration. It is observed that C4 photosynthesis is more efficient than C3 photosynthesis under conditions of low atmospheric CO2, heat, drought and salinity, suggesting that these factors are the important drivers to promote C4 evolution. Although C4 evolution took over 66 times independently, it is hypothesized that it shared the following evolutionary trajectory: 1) gene duplication followed by neofunctionalization; 2) anatomical and ultrastructral changes of leaf architecture to improve the hydraulic systems; 3) establishment of two-celled photorespiratory pump; 4) addition of transport system; 5) co-option of the duplicated genes into C4 pathway and adaptive changes of C4 enzymes. Based on our current understanding on C4 evolution, several strategies for engineering C4 rice have been proposed to increase both photosynthetic efficiency and yield significantly in order to avoid international food crisis in the future, especially in the developing countries. Here we summarize the latest progresses on the studies of C4 evolution and discuss the strategies to introduce two-celled C4 pathway into rice.

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Physiological, anatomical and biochemical characterisation of photosynthetic types in genus Cleome (Cleomaceae)

Functional Plant Biology ◽

10.1071/fp06287 ◽

2007 ◽

Vol 34 (4) ◽

pp. 247 ◽

Cited By ~ 41

Author(s):

Elena V. Voznesenskaya ◽

Nuria K. Koteyeva ◽

Simon D. X. Chuong ◽

Alexandra N. Ivanova ◽

João Barroca ◽

...

Keyword(s):

Leaf Anatomy ◽

C4 Photosynthesis ◽

C3 Plants ◽

Intermediate Species ◽

Δ13c Values ◽

C4 Species ◽

Cleome Gynandra ◽

The Family ◽

C3 Species ◽

C4 Pathway

C4 photosynthesis has evolved many times in 18 different families of land plants with great variation in leaf anatomy, ranging from various forms of Kranz anatomy to C4 photosynthesis occurring within a single type of photosynthetic cell. There has been little research on photosynthetic typing in the family Cleomaceae, in which only one C4 species has been identified, Cleome gynandra L. There is recent interest in selecting and developing a C4 species from the family Cleomaceae as a model C4 system, since it is the most closely related to Arabidopsis, a C3 model system (Brown et al. 2005). From screening more than 230 samples of Cleomaceae species, based on a measure of the carbon isotope composition (δ13C) in leaves, we have identified two additional C4 species, C. angustifolia Forssk. (Africa) and C. oxalidea F.Muell. (Australia). Several other species have δ13C values around –17‰ to –19‰, suggesting they are C4-like or intermediate species. Eight species of Cleome were selected for physiological, anatomical and biochemical analyses. These included C. gynandra, a NAD–malic enzyme (NAD–ME) type C4 species, C. paradoxa R.Br., a C3–C4 intermediate species, and 6 others which were characterised as C3 species. Cleome gynandra has C4 features based on low CO2 compensation point (Γ), C4 type δ13C values, Kranz-type leaf anatomy and bundle sheath (BS) ultrastructure, presence of C4 pathway enzymes, and selective immunolocalisation of Rubisco and phosphoenolpyruvate carboxylase. Cleome paradoxa was identified as a C3–C4 intermediate based on its intermediate Γ (27.5 μmol mol–1), ultrastructural features and selective localisation of glycine decarboxylase of the photorespiratory pathway in mitochondria of BS cells. The other six species are C3 plants based on Γ, δ13C values, non-Kranz leaf anatomy, and levels of C4 pathway enzymes (very low or absent) typical of C3 plants. The results indicate that this is an interesting family for studying the genetic basis for C4 photosynthesis and its evolution from C3 species.

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Novel QTL Associated with Shoot Branching Identified in Doubled Haploid Rice (Oryza sativa L.) under Low Nitrogen Cultivation

Genes ◽

10.3390/genes12050745 ◽

2021 ◽

Vol 12 (5) ◽

pp. 745

Author(s):

Youngho Kwon ◽

Nkulu Rolly Kabange ◽

Ji-Yun Lee ◽

So-Myeong Lee ◽

Jin-Kyung Cha ◽

...

Keyword(s):

Doubled Haploid ◽

Phenotypic Variation ◽

Growth And Development ◽

Oryza Sativa L ◽

Tiller Number ◽

Yield Potential ◽

Doubled Haploid Population ◽

Shoot Branching ◽

Normal Nitrogen ◽

Low Nitrogen

Shoot branching is considered as an important trait for the architecture of plants and contributes to their growth and productivity. In cereal crops, such as rice, shoot branching is controlled by many factors, including phytohormones signaling networks, operating either in synergy or antagonizing each other. In rice, shoot branching indicates the ability to produce more tillers that are essential for achieving high productivity and yield potential. In the present study, we evaluated the growth and development, and yield components of a doubled haploid population derived from a cross between 93-11 (P1, indica) and Milyang352 (P2, japonica), grown under normal nitrogen and low nitrogen cultivation open field conditions. The results of the phenotypic evaluation indicated that parental lines 93-11 (P1, a high tillering indica cultivar) and Milyang352 (P2, a low tillering japonica cultivar) showed distinctive phenotypic responses, also reflected in their derived population. In addition, the linkage mapping and quantitative trait locus (QTL) analysis detected three QTLs associated with tiller number on chromosome 2 (qTNN2-1, 130 cM, logarithm of the odds (LOD) 4.14, PVE 14.5%; and qTNL2-1, 134 cM, LOD: 6.05, PVE: 20.5%) and chromosome 4 (qTN4-1, 134 cM, LOD 3.92, PVE 14.5%), with qTNL2-1 having the highest phenotypic variation explained, and the only QTL associated with tiller number under low nitrogen cultivation conditions, using Kompetitive Allele-Specific PCR (KASP) and Fluidigm markers. The additive effect (1.81) of qTNL2-1 indicates that the allele from 93-11 (P1) contributed to the observed phenotypic variation for tiller number under low nitrogen cultivation. The breakthrough is that the majority of the candidate genes harbored by the QTLs qTNL2-1 and qTNN4-1 (here associated with the control of shoot branching under low and normal nitrogen cultivation, respectively), were also proposed to be involved in plant stress signaling or response mechanisms, with regard to their annotations and previous reports. Therefore, put together, these results would suggest that a possible crosstalk exists between the control of plant growth and development and the stress response in rice.

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Genetic Diversity of Local Upland Rice (Oryza sativa L.) Genotypes Based on Agronomic Traits and Yield Potential in North Buton, Indonesia

Asian Journal of Crop Science ◽

10.3923/ajcs.2017.109.117 ◽

2017 ◽

Vol 9 (4) ◽

pp. 109-117 ◽

Cited By ~ 9

Author(s):

Budianti Kadidaa ◽

Gusti Ray Sadimantar ◽

Suaib . ◽

La Ode Safuan ◽

Muhidin .

Keyword(s):

Genetic Diversity ◽

Oryza Sativa ◽

Agronomic Traits ◽

Upland Rice ◽

Oryza Sativa L ◽

Yield Potential

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Genetic Diversity of Bacterial Blight Resistant Rice (Oryza sativa L.) Genotypes from INGER

Bangladesh Rice Journal ◽

10.3329/brj.v23i2.48248 ◽

2020 ◽

Vol 23 (2) ◽

pp. 59-64

Author(s):

F Akter ◽

MZ Islam ◽

A Akter ◽

SK Debsharma ◽

A Shama ◽

...

Keyword(s):

Genetic Diversity ◽

Bacterial Blight ◽

Oryza Sativa L ◽

Mean Value ◽

Grain Weight ◽

Yield Potential ◽

Growth Duration ◽

Panicle Number ◽

Cluster Distance ◽

1000 Grain Weight

Genetic diversity of 65 rice genotypes was studied from IRBBN (International Rice Bacterial Blight Nursery) of INGER (International Network for Genetic Evaluation of Rice) materials through Mahalanobis D2 statistic for grain yield and yield contributing characters. The genotypes were grouped into five clusters. The inter-cluster distances were higher than intra-cluster distances indicating wider genetic diversity among the genotypes of different clusters. The intra-cluster distances were lower in all the cases reflecting homogeneity of the genotypes within the clusters. The cluster III contained the highest number of genotypes (23) and the clusterv contained the lowest (8). The highest intra-cluster distance was noticed for the cluster I and lowest for cluster III. The highest inter-cluster distance was observed between cluster I and V, followed by cluster IV and V, cluster II andV and the lowest between cluster I and IV. Regarding inter-cluster distance, the genotypes of cluster V showed high genetic distance from all other clusters. The genotypes from cluster V could be hybridized with the genotypes of other clusters for producing transgressive segregants. Based on canonical vector analysis, panicle number per plant had maximum contribution towards genetic divergence. The highest cluster means for yield, grain/panicle and spikelet fertility were obtained from cluster V. The highest means for 1000 grain weight, second higher yield and the lowest growth duration were found in cluster II, while the lowest mean value for yield and 1000 grain weight and higher mean value for growth duration were found in cluster IV. The crosses between the genotypes/parents of cluster V and cluster II, cluster V and cluster I would exhibit high heterosis as well as higher level of yield potential. Therefore, more emphasis should be given for selection of the genotypes from clusters II and V for future breeding programme. Bangladesh Rice j. 2019, 23(2): 59-64

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C4 Photosynthesis in Sodium-Deficient Plants

Functional Plant Biology ◽

10.1071/pp9790431 ◽

1979 ◽

Vol 6 (4) ◽

pp. 431 ◽

Cited By ~ 6

Author(s):

TS Boag ◽

PF Brownell

Keyword(s):

C4 Photosynthesis ◽

Dicarboxylic Acids ◽

C4 Plants ◽

Compensation Point ◽

Short Term ◽

Sodium Deficiency ◽

Co2 Compensation Point ◽

Δ13c Value ◽

C4 Pathway ◽

Chloris Barbata

The C4 plants Kochia childsii Hort. and Chloris barbata Sw. showed symptoms characteristic of sodium deficiency. The δ13C value, CO2 compensation point and percentage of 14C label in C4 dicarboxylic acids in short-term photosynthesis were similar in sodium-deficient and normal plants. This is consistent with the operation of the C4 pathway.

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