Patent Description:
Plant breeders are continuously looking for more efficient ways to cultivate plants. One way to increase the efficiency is by high-wire cultivation. In the high-wire cultivation, higher planting densities are used to obtain higher yields per m<NUM>. In addition, high-wire cultivation allows a longer cultivation period during which the plant produces fruits. Cucumber and tomato are crops that are suitable for high-wire cultivation. However, not all varieties are fit for this type of cultivation.

More efficient cultivation can also be achieved in other crops if the plants have a compact growth phenotype. Such a compact growth phenotype may be characterized by the plants showing shorter internodes and/or a smaller leave area. Because of this compact growth phenotype, the plants can be planted in higher densities, thereby saving a lot of space.

It is one goal of the present invention to provide a plant type that enables efficient cultivation. This goal has been achieved by providing a plant type showing a compact growth phenotype.

In the research leading to the present invention, it was found that a mutation in the Cullin1 gene leads to a modification in plant type that may be expressed as a compact growth phenotype. A plant that has the mutant gene is in particular suitable for efficient cultivation. Such a plant shows a shorter internode length and/or a smaller leaf area and may also display other characteristics that lead to a compact growth phenotype.

Cullin proteins are a family of proteins present in all eukaryotes, not only plants. The Cullin proteins combine with RING proteins to form so-called Cullin-RING ubiquitine ligases (CRLs). In general, Cullin proteins play an important role in protein ubiquitination and protein degradation.

Ubiquitination (also known as ubiquitylation) is an enzymatic, post-translational modification process in which an ubiquitin protein is ligated to substrate protein.

Ubiquitine is a highly conserved, small polypeptide, ubiquitously distributed among eukaryotes. An ATP-dependent reaction cascade (involving the sequential action of ubiquitine-activating (E1s), ubiquitine-conjugating (E2s) and ubiquitine-protein ligase (E3s) enzymes) performs the ligation of ubiquitine to other proteins. Proteins that are ligated with ubiquitine are subsequently degraded and broken down, or relocated.

The Cullin1 protein, which is a member of the Cullin protein family, is one out of the four subunits that make up the SCF complex. The abbreviation SCF stands for SKP1-CUL1-F-box protein E3 ubiquitin ligase complex, which mediates the ubiquitination of proteins involved in cell cycle progression, signal transduction and transcription. In the SCF complex, Cullin1 serves as a rigid scaffold that organizes the SKP1-F-box protein and RBX1 subunits. It may contribute to catalysis through positioning of the substrate and the ubiquitin-conjugating enzyme.

As mentioned before, Cullin proteins are present in all eukaryotes. Through its involvement in ubiquitination and subsequent processes it is engaged in a wide range of cellular processes. Surprisingly, the mutation of the invention causes shorter internode length and/or smaller leaf area without causing a deleterious effect on the plant, which would be expected based on the state of the art knowledge available on the conserved status of Cullin1 protein and its functionality.

The characterisation of the modified Cullin1 gene in the present research was performed in cucumber (Cucumis sativus). This enabled the identification of further crops having a Cullin1 gene, which when modified leads to plants with a compact growth phenotype, i.e. showing shorter internode length and/or a smaller leaf area, or a reduction in other plant parts when compared to plants not having the modified Cullin1 gene. These crops include those belonging to the family of Cucurbitacea, such as for instance melon (Cucumis melo), watermelon (Citrullus lanatus), and squash (Cucurbita pepo); fruit crops, such as pepper (Capsicum annuum), tomato (Solanum lycopersicum), and eggplant (Solanum melongena); leafy vegetables, such as lettuce (Lactuca sativa), spinach (Spinacia oleracea), chicory (Cichorium intybus), and cabbage (Brassica oleracea); root vegetables, such as for instance carrot (Daucus carota), radish (Raphanus sativus), and beetroot (Beta vulgaris); and other crops, such as celery (Apium graveolens) and leek (Allium ampeloprasum).

It is another goal of the present invention to provide a plant type that is suitable for situations that require smaller portions, or reduces the labour, time and expenses involved with storing, handling and transporting of redundant plant leaves.

The invention thus relates to a modified Cullin1 gene comprising a modification in the wild type Cullinl nucleotide sequence of SEQ ID No: <NUM>:, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM> which leads to a substitution in the wild type Cullin1 amino acid sequence of SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO:<NUM>, SEQ ID NO. <NUM>, SEQ ID NO: <NUM> respectively, wherein the substitution in the amino acid sequence is found in the part of the Cullin1 protein between the amino acids on positions <NUM>-<NUM> of the cucumber amino acid sequence of SEQ ID No: <NUM>, or, on a position corresponding thereto, for other crops, wherein the modification in the amino acid sequence is found in the part of the Cullin1 protein that binds SKP1 and/or ETA-<NUM>, and wherein the modified Cullin1 gene is capable of causing a compact growth phenotype in a plant comprising said modified Cullin1 gene.

The invention further relates to the modified Cullin1 gene, wherein the substitution in the amino acid sequence is found in the part of the Cullin1 protein between the amino acids on positions <NUM>-<NUM> of the cucumber amino acid sequence of SEQ ID No: <NUM>, or, on a position corresponding thereto, for other crops.

The Cullin1 gene can be modified by different means known in the art, including mutagenesis. Mutagenesis comprises the random introduction of at least one modification to DNA by means of one or more chemical compounds, such as ethyl methanesulphonate (EMS), nitrosomethylurea, hydroxylamine, proflavine, N-methyl-N-nitrosoguanidine, N-ethyl-N-nitrosourea, N-methyl-N-nitro-nitrosoguanidine, diethyl sulphate, ethylene imine, sodium azide, formaline, urethane, phenol and ethylene oxide, and/or by physical means, such as UV-irradiation, fast-neutron exposure, X-rays, gamma irradiation, and/or by insertion of genetic elements, such as transposons, T-DNA, retroviral elements. Mutagenesis also comprises the more specific, targeted introduction of at least one modification by means of homologous recombination, oligonucleotide-based mutation induction, zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs) or Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR) systems.

The modified Cullin1 gene may be an exogenous Cullin1 gene introduced into a plant by a transgenic method or a cisgenic method. Use of a modified Cullin1 gene of the invention for developing a plant that shows a compact growth phenotype, i.e. comprises shorter internodes and/or smaller leaf area, consists of the introduction of a modified exogenous Cullin1 gene by a transgenic or a cisgenic method.

The modified Cullin1 gene may be part of a gene construct, which gene construct comprises a selectable marker, a promoter sequence, a Cullin1 gene sequence, and a terminator sequence.

The present invention is widely applicable to all plant species that have a functional orthologue of the Cullin1 gene in their genome, i.e. an orthologue that performs the same or a similar biological function. Identification of Cullin1 orthologues, i.e. Cullin1 genes in other species, can be performed in many crops, methods of which are known in the art. The present invention can for instance be applied to a plant belonging to a species selected from the group consisting of, Cucumis melo, Cucurbita pepo, Citrullus lanatus, Solanum melongena, Solanum lycopersicum, Capsicum annuum, Brassica oleracea, Daucus carota, Apium graveolens, Cichorium intybus, Cichorium endivia, Allium ampeloprasum, Lactuca sativa, Raphanus sativus, Spinacia oleracea, and Beta vulgaris.

Disclosed herein is a modified Cullin1 gene comprising a modification in the wild type Cullin1 nucleotide sequence of SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM> which leads to a modification in the wild type Cullin1 amino acid sequence of SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO:<NUM>, SEQ ID NO. <NUM>, SEQ ID NO: <NUM> respectively.

<FIG> show the wild type Cullin1 nucleotide sequences SEQ ID NO. <NUM>-<NUM> of Cucumis sativus, Cucumis melo, Cucurbita pepo, Citrullus lanatus, Solanum melongena, Solanum lycopersicum, Capsicum annuum, Brassica oleracea, Daucus carota, Apium graveolens, Cichorium intybus, Cichorium endivia, Allium ampeloprasum, Lactuca sativa, Raphanus sativus, Spinacia oleracea, and Beta vulgaris, respectively. <FIG> show the wild type Cullin1 amino acid sequences SEQ ID NO. <NUM>-<NUM> of Cucumis sativus, Cucumis melo, Cucurbita pepo, Citrullus lanatus, Solanum melongena, Solanum lycopersicum, Capsicum annuum, Brassica oleracea, Daucus carota, Apium graveolens, Cichorium intybus, Cichorium endivia, Allium ampeloprasum, Lactuca sativa, Raphanus sativus, Spinacia oleracea, and Beta vulgaris, respectively.

The term "wild type" as used herein refers in general to the form of an organism, gene, protein, or trait as it would occur in nature, as opposed to a mutated or modified form. In this application wild type refers specifically to the naturally occurring form of the Cullin1 gene, the naturally occurring form of the nucleotide sequence of Cullin1 and the naturally occurring form of the Cullin1 amino acid sequence. The naturally occurring forms of the Cullin1 gene and Cullin1 protein of several crops are shown in <FIG> and <FIG> respectively.

The terms "mutant", "mutation", "modification" ,"modified", "mutated Cullin1 gene" and "modified Cullin1 gene" as used herein refer to nucleotide changes and amino acid changes to the wild type Cullin1 gene thereof that lead to a modified version of the wild type gene. The modification can be any modification, including but not limited to a SNP.

The modified Cullin1 gene is also referred to herein as "the gene of the invention", "the modified Cullin1 gene", or "the modified Cullin1 gene of the invention". These terms are used interchangeably herein. As used herein the phrase "the modified Cullin1 gene" is intended to encompass the Cullin1 gene with any modification that leads to the compact growth phenotype.

The terms "compact gene phenotype", "compact phenotype" or "compact growth phenotype" are used interchangeably herein and refer to a phenotype of a shorter internode length and/or a smaller leaf area. Crops comprising the modified Cullin1 gene and which have internodes, such as for instance cucumber, may show shorter internodes or a smaller leaf area. They may also show shorter internodes and a smaller leaf area. Crops comprising the modified Cullin1 gene but which do not have internodes, such as for instance lettuce, may show a smaller leaf area. The term "smaller leaf area" as used herein is the leaf area that displays a reduction in individual leaf area of, in order of increased preference, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>% as a result of the homozygous or heterozygous presence of the modified gene of the invention. To investigate the influence of the gene of the invention on the smaller leaf area, a skilled person would have to compare plants having the gene of the invention homozygously or heterozygously with plants that are isogenic to first mentioned plants but do not have the gene of the invention.

With the term "leaf" is meant the part of the plant consisting of the petiole and leaf blade. With the term "leaf area" is meant the surface of the part of the plant consisting of the leaf blade.

The term "shorter internodes" or "shorter internode length" as used herein is internode length that has a reduction in individual length of, in order of increased preference, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>% as a result of the homozygous or heterozygous presence of the gene of the invention. To investigate the influence of the gene of the invention on the shorter internode length, a skilled person would have to compare plants having the gene of the invention homozygously or heterozygously with plants that are isogenic to first mentioned plants but without the gene of the invention.

The modification leading to the modified Cullin1 gene may be selected from a modification that changes the mRNA level of the Cullin1 gene, a modification that changes the Cullin1 protein structure and/or levels, and/or a modification that changes the Cullin1 protein activity.

Disclosed herein is a modified Cullin1 gene, comprising a mutation as compared to its wild type genomic sequence, which mutation leads to a change in the Cullin1 protein and/or protein activity, wherein the modified Cullin1 gene is capable of causing a compact growth phenotype.

The mutation as disclosed herein may be a Single Nucleotide Polymorphism (SNP).

The physical location of the amino acid substitution in the Cullin1 protein lies in the region of the protein where the Cullin1 protein binds to SKP1 and/or ETA2. The Cullin1 protein forms a so-called SCF complex, together with SKP1, RBX1 and a F-box protein, which has important functionalities such as a role in leaf development. ETA2 is according to some theories, required to sustain the SCF complex activity, most probably by facilitating cycles of assembly and disassembly of the SCF complex.

The modified Cullin1 gene may include, a Cullin1 gene comprising a SNP on position <NUM> of SEQ ID NO. <NUM> of cucumber, or on a position corresponding thereto in the Cullinl gene of other crops, wherein the modification comprises a change in the nucleotide on that position and wherein the modification leads to an amino acid substitution in the Cullin1 protein on position <NUM> of the wildtype protein sequence SEQ ID NO: <NUM>. of cucumber, or on a position corresponding thereto, in other crops. In cucumber the change is from A to G and from Isoleucine to Methionine. In other crops the change in nucleotide and amino acid may be different.

The modification of the nucleotide sequence may comprise a change from Adenine, Cytosine or Thymine to Guanine.

The definition "coding sequence" as used herein is the portion of the gene's DNA composed of exons that code for the protein.

The modification in the amino acid sequence may be a substitution on position <NUM> of the cucumber amino acid sequence of SEQ ID No: <NUM>, or, in case of a crop other than cucumber, on a position corresponding to position <NUM> of the cucumber amino acid sequence of SEQ ID No: <NUM>.

Disclosed herein is that an amino acid substitution caused by a mutation of the current invention was found to be present on position <NUM> of the cucumber amino acid sequence of SEQ ID No: <NUM>, or, in case of a crop other than cucumber, on a position corresponding to position <NUM> of the wild type amino acid sequence SEQ ID NO. <NUM> of cucumber. This nucleotide mutation is considered to be non-conservative, and the amino acid change can be considered non-conservative.

Amino acid changes in a protein occur when the mutation of one or more base pairs in the coding DNA sequence result in an altered codon triplet that encodes a different amino acid. Not all point mutations in the coding DNA sequence lead to amino acid changes, due to the redundancy of the genetic code. Mutations in the coding sequence that do not lead to amino acid changes are called "silent mutations". Other mutations are called "conservative", they lead to the replacement of one amino acid by another amino acid with comparable properties, such that the mutations are unlikely to change the folding of the mature protein, or influence its function. As used herein a "non-conservative amino acid change" refers to an amino acid that is replaced by another amino acid that has different chemical properties that may lead to decreased stability, changed functionality and/or structural effects of the encoded protein.

Further disclosed herein is that the modification in the amino acid sequence is a substitution and may consist of a change from Isoleucine to Methionine.

The invention further relates to a plant comprising the modified Cullin1 gene, wherein the plant does not belong to the species Cucumis sativus.

A Cucumis sativus plant comprising the modified Cullin1 gene with the nucleotide sequence of SEQ ID No: <NUM> is not part of this invention and is therefore disclaimed herewith.

A plant comprising the modified Cullin1 gene shows a compact growth phenotype, i.e. comprises a shorter internode length and/or a smaller leaf area, compared to an isogenic plant of the same species not comprising the modified Cullin1 gene. For example, a Cucumis sativus plant a Cucumis melo plant, a Cucurbita pepo plant, a Citrullus lanatus plant, a Solanum melongena plant, a, Solanum lycopersicum plant, and a Capsicum annuum plant comprising the modified Cullin1 gene show a shorter internode length and/or a smaller leaf area. These plants are therefore particularly suitable for efficient cultivation. A Cichorium intybus plant, a Cichorium endivia plant, a Lactuca sativa plant, a Brassica oleracea plant and a Spinacia oleracea plant comprising the modified Cullin1 gene show for example a smaller leaf area. As such, the parts of these plants harvested for consumption are smaller in size. These plants are therefore particularly suitable for a situation in which smaller portions are required. A Daucus carota plant comprising the modified Cullin1 gene shows a shorter internode length and/or a smaller leaf area. As such, the plant comprises less foliage that needs to be removed before the product is sold and/or consumed. An Apium graveolens plant comprising the modified Cullin1 gene shows a shorter internode length and/or a smaller leaf area. As such, the plant is of a more compact size suitable for a situation in which smaller portions are required and/or comprises less foliage that needs to be removed before the product is sold and/or consumed. An Allium ampeloprasum plant comprising the modified Cullin1 gene shows a smaller leaf area. As such, the leaves that are not consumed do not need to be removed before the product is sold and/or consumed. A Raphanus sativus plant and a Beta vulgaris plant comprising the modified Cullin1 gene show a smaller leaf area. As such, less foliage needs to be removed before the product is sold and/or consumed.

The plant as disclosed herein comprising the modified Cullin1 gene either homozygously or heterozygously may be a plant of an inbred line, a hybrid, a doubled haploid, or a plant of a segregating population.

The disclosed plant may have the modified Cullin1 gene in heterozygous state since such a plant shows the trait in an intermediate level. Furthermore such plant may be a potential source of the gene and when crossed with another plant that optionally also has the modified gene either homozygously or heterozygously can result in progeny plants that have the modified gene homozygously or heterozygously and show the trait of having a compact growth phenotype.

Also disclosed herein is a method for the production of a plant having the modified Cullin1 gene that leads to a compact growth phenotype by using a seed that comprises the modified Cullin1 gene for growing the said plant.

A further disclosure relates to a method for the production of a plant having the modified Cullin1 gene by using tissue culture of plant material that carries the modified Cullin1 gene in its genome.

Also disclosed herein is a method for the production of a plant having the modified Cullin1 gene which leads to a compact growth phenotype, by using vegetative reproduction of plant material that carries the modified Cullin1 gene in its genome.

Also disclosed herein is a method for the production of a plant having the modified Cullin1 gene by using a doubled haploid generation technique to generate a doubled haploid line from a cucumber plant comprising the modified Cullin1 gene.

The invention further relates to a plant seed comprising the modified Cullin1 gene of the invention, wherein the plant seed does not belong to the species Cucumis sativus, and wherein the plant that can be grown from the seed shows a compact growth phenotype.

Also disclosed herein is a method for seed production comprising growing plants from seeds of the invention, allowing the plants to produce seeds by allowing pollination to occur, and harvesting those seeds. Such production of seeds is suitably done by crossing or selfing. Seeds produced in that manner result in a compact growth phenotype of the plants grown thereof.

Further disclosed herein is hybrid seed and a method for producing such hybrid seed comprising crossing a first parent plant with a second parent plant and harvesting the resultant hybrid seed, wherein said first parent plant and/or said second parent plant has the modified Cullin1 gene of the invention. A hybrid plant resulting from growing the resulting seed that comprises the modified Cullin1 gene of the invention, showing the compact growth phenotype of the invention is also disclosed herein.

Another aspect of the invention relates to propagation material capable of developing into and/or being derived from a plant comprising a modified Cullin1 gene, wherein the plant shows a compact growth phenotype, compared to an isogenic plant of the same species not comprising the modified Cullin1 gene, wherein the propagation material comprises the modified Cullin1 gene of the invention and wherein the propagation material is selected from the group consisting of microspores, pollen, ovaries, ovules, embryos, embryo sacs, egg cells, cuttings, roots, hypocotyls, cotyledons, stems, leaves, flowers, anthers, seeds, meristematic cells, protoplasts and cells, or tissue culture thereof.

Also disclosed herein are parts of a claimed plant that are suitable for sexual reproduction. Such parts are for example selected from the group consisting of microspores, pollen, ovaries, ovules, embryo sacs, and egg cells. In addition, disclosed herein are parts of a claimed plant that are suitable for vegetative reproduction, which are in particular cuttings, roots, stems, cells, protoplasts. The parts of the plants as mentioned above are considered propagation material. The plant that is produced from the propagation material comprises the modified Cullin1 gene that leads to a compact growth phenotype and thus enables efficient cultivation and/or is suitable for the production for market segments that require a smaller product.

Furthermore, disclosed herein is a tissue culture of a plant carrying the modified Cullin1 gene of the invention, which is also propagation material. The tissue culture comprises regenerable cells. Such tissue culture can be selected or derived from any part of the plant, in particular from leaves, pollen, embryos, cotyledon, hypocotyls, meristematic cells, roots, root tips, anthers, flowers, seeds, and stems. The tissue culture can be regenerated into a plant carrying the modified Cullin1 gene of the invention, which regenerated plant expresses the trait of the invention.

The invention further relates to the use of the modified Cullin1 gene for the development of a plant showing a compact growth phenotype as compared to an isogenic plant not comprising the modified Cullin1 gene, consisting of the introduction of a modified exogenous Cullin1 gene by a transgenic or a cisgenic method.

The invention further relates to the use of the modified Cullin1 gene, or a part thereof comprising the modification, as a marker for identifying a plant showing a compact growth phenotype.

The 'use for identifying' or a 'method for identifying' as used in the current application comprises the use of the described (causal) SNP in the Cullin1 gene as a marker. The invention also relates to other markers that can be developed based on a modification, including the causal SNP, in the Cullin1 gene, as well as to other markers that can be developed based on the wildtype sequence of the Cullin1 gene.

The invention further relates to the use of any of the sequences of SEQ ID NOs. <NUM>-<NUM>, or a part thereof, as a marker for identifying a plant showing a compact growth phenotype, i.e. comprising a shorter internode length and/or a smaller leaf area. If a part of any of these sequences is used, the part must comprise the modification. For example, SEQ ID No. <NUM> or a part thereof may be used to identify a Cucumis sativus plant showing a shorter internode length and/or a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Cucumis melo plant showing a shorter internode length and/or a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Cucurbita pepo plant showing a shorter internode length and/or a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Citrullus lanatus plant showing a shorter internode length and/or a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Solanum melongena plant showing a shorter internode length and/or a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Solanum lycopersicum plant showing a shorter internode length and/or a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Capsicum annuum plant showing a shorter internode length and/or a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Brassica oleracea plant showing a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Daucus carota plant showing a shorter internode length and/or a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Apium graveolens plant showing a shorter internode length and/or a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Cichorium intybus plant showing a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Cichorium endivia plant showing a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify an Allium ampeloprasum plant showing a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Lactuca sativa plant showing a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Raphanus sativus plant showing a shorter internode length and/or a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Spinacia oleracea plant showing a smaller leaf area; SEQ ID No. <NUM> or a part thereof may be used to identify a Beta vulgaris plant showing a shorter internode length and/or a smaller leaf area. Also disclosed herein is the use of any markers that are derived from SEQ ID Nos. <NUM>-<NUM> or SEQ ID NOs. <NUM>-<NUM> for identifying a plant showing a compact growth phenotype. Any such derived marker must comprise the modification that leads to the phenotype of the invention.

In general, to identify a plant showing a compact growth phenotype, it is thus determined in the Cullin1 gene whether there is an A, C, or T (SEQ ID Nos. <NUM>-<NUM>) or a G (SEQ ID Nos. <NUM>-<NUM>) on position <NUM>, or a position corresponding thereto.

Also disclosed herein is a method for obtaining a plant which shows a compact growth phenotype comprising;.

A further disclosure relates to a method for obtaining a plant which shows a compact growth phenotype comprising;.

Also disclosed herein is a marker for identifying a plant showing a compact growth phenotype, comprising the modified Cullin1, or a part thereof that comprises the modification. The modification may be a nucleotide substitution on or around position <NUM> of SEQ ID No: <NUM> of cucumber, or, in case of a crop other than cucumber, on or around a position corresponding to position <NUM> of SEQ ID No:<NUM> of cucumber, which modification leads to an amino acid substitution in the Cullin1 protein.

Also disclosed herein is a method for selecting a plant showing a compact growth phenotype from a population of plants, comprising detecting the presence or absence of a guanine on position <NUM> of the cucumber nucleotide sequence of SEQ ID NO:<NUM>, or, for a crop other than cucumber, on a position corresponding to position <NUM> of the cucumber nucleotide sequence of SEQ ID No: <NUM>, in the genome of a plant of a population of plants, and selecting a plant comprising a guanine on position <NUM> of SEQ ID NO: <NUM>, as shown in SEQ ID NO. <NUM>, or, for a crop other than cucumber, on a position corresponding to position <NUM> of the cucumber nucleotide sequence of SEQ ID No: <NUM>, as shown in any of SEQ ID Nos. <NUM>- <NUM>.

A F2 crossing population made from a commercially available "high wire" cucumber variety, "Hi Lisa", was used to create a new genetic map. In total, <NUM> markers and <NUM> F2 lines are used. A QTL analysis performed on these crossing populations revealed a major QTL on chromosome <NUM> that causes a smaller internode length and a smaller leaf surface. Sequencing of the peak marker of the QTL revealed a SNP present in the marker sequence. The particular sequence was polymorphic in the crossing population. The nucleotide sequence of the major QTL on chromosome <NUM> was identified by means of BLAST. The best BLAST hits for the sequence all resembled the sequence of the Cullin1 gene.

Different populations of Cucumis sativus plants, each made with different commercially available 'high wire' varieties, having the phenotype of shorter internodes, and smaller leaves, were phenotypically and genetically analysed. See Table <NUM> for the phenotypic and genetic data. Plants were measured <NUM> weeks after sowing. For estimating the leaf area, from the second leaf on (not the cotyledons) all leafs present were measured, and the width and the length of a leaf were measured and multiplied with each other to obtain a (roughly estimation) score for leaf area. In the third column of Table <NUM>, the different haplotypes for the Cullin1 gene SNP are given. The score A means that the SNP marker scored homozygous wildtype Cullin1 gene, B means homozygous modified Cullin1 gene.

In the first population, plants that are homozygous for the modified Cullin1 gene (B), show an internode length that is on average <NUM>% of the length of the plants that score homozygous for the wild type Cullin1 gene (A). The B plants (homozygous for the modified Cullin1 gene) show a leaf area that is on average <NUM>% of the length of the A plants (homozygous for the wild type Cullin1 gene).

In the second population, B plants show on average an internode length that is <NUM>% and a leaf area that is <NUM>% of the A plants of the same population.

In the third population, the B plants show on average an internode length of <NUM>% and a leaf area of <NUM>%, compared to the average of the A plants.

Melon seeds were treated with EMS by submergence of approximately <NUM> seeds into an aerated solution of <NUM>% (w/v) EMS during <NUM> hours at room temperature. The treated seeds were germinated on paper in a small plastic container and the resulting plants were grown and self-pollinated in a greenhouse to produce seeds. After maturation, these seeds were harvested and bulked in one pool. The resulting pool of seeds was used as starting material to identify the individual plants that show smaller internode length and/or smaller leaf area.

The Cullin1 mutants which were obtained were grown in a greenhouse in order to produce lines by self-fertilisation. Melon plant lines were analysed to confirm the smaller internode length and smaller leaf area. When a line was segregating for smaller internode length and/or smaller leaf area, plants were selected and after an additional cycle of inbreeding Cullin1 lines were selected. Cullin1 mutants were identified by their shorter internodes and/or smaller leaf area in comparison with control lines.

Claim 1:
Modified Cullin1 gene comprising a modification in the wild type Cullin1 nucleotide sequence of SEQ ID No: <NUM>:, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM> which leads to a substitution in the wild type Cullin1 amino acid sequence of SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID No: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO: <NUM>, SEQ ID NO:<NUM>, SEQ ID NO. <NUM>, SEQ ID NO: <NUM> respectively, wherein the substitution in the amino acid sequence is found in the part of the Cullin1 protein between the amino acids on positions <NUM>-<NUM> of the cucumber amino acid sequence of SEQ ID No: <NUM>, or, on a position corresponding thereto, for other crops, wherein the modification in the amino acid sequence is found in the part of the Cullin1 protein that binds SKP1 and/or ETA-<NUM>, and wherein the modified Cullin1 gene is capable of causing a compact growth phenotype in a plant comprising said modified Cullin1 gene.