Methods and compositions for watermelon sex expression

Abstract

The present disclosure provides for unique watermelon plants with a desired sex expression phenotype and their progeny. Such plants may comprise an introgressed QTL associated with a desired sex expression phenotype. In certain aspects, compositions, including distinct polymorphic molecular markers, and methods for producing, breeding, identifying, selecting, and the like of plants or germplasm with a desired sex expression phenotype are provided.

What is claimed is: 
     
         1 . A watermelon plant comprising in its genome at least one introgressed allele locus associated with a desired sex expression phenotype, wherein the locus is in or genetically linked to a genomic region defined by:
 loci NW0248967 (SEQ ID NO:1) and NW0248118 (SEQ ID NO:3) on linkage group 2 (LG2), or within 15 cM thereof;   loci NW0252278 (SEQ ID NO:4) and NW0248560 (SEQ ID NO:5) on linkage group 7 (LG7), or within 15 cM thereof;   loci NW0248392 (SEQ ID NO:6) and NW0248711 (SEQ ID NO:7) on linkage group 10 (LG10), or within 15 cM thereof;   loci NW0249365 (SEQ ID NO:8) and NW0250112 (SEQ ID NO:9) on linkage group 11A (LG11A), or within 15 cM thereof; or   loci NW0249365 (SEQ ID NO:8) and NW0250956 (SEQ ID NO:10) on linkage group 11A (LG11A), or within 15 cM thereof;   loci NW0250956 (SEQ ID NO:10) and NW0250112 (SEQ ID NO:9) on linkage group 11A (LG11A), or within 15 cM thereof;   or a progeny plant therefrom.   
     
     
         2 . The watermelon plant of  claim 1  wherein the plant is dioecious. 
     
     
         3 . The watermelon plant of  claim 1  wherein the plant is a tetraploid or a diploid. 
     
     
         4 . The watermelon plant of  claim 1  wherein the desired sex expression phenotype is selected from the group consisting of percent male flowers, percent female flowers, percent hermaphroditic flowers, and percent female of total pistillate flowers. 
     
     
         5 . The watermelon plant of  claim 4 , wherein said percent male flowers or percent hermaphroditic flowers is at least about 90%. 
     
     
         6 . The watermelon plant of  claim 4 , wherein said percent female flowers is at least about 90%. 
     
     
         7 . The watermelon plant of  claim 1 , wherein the locus is in or genetically linked to a genomic region defined by:
 loci NW0248967 (SEQ ID NO:1) and NW0251455 (SEQ ID NO:11) on LG2;   loci NW0248118 (SEQ ID NO:3) and NW0251455 (SEQ ID NO:11) on LG2;   loci NW0252278 (SEQ ID NO:4) and NW0249392 (SEQ ID NO:12 on LG7;   loci NW0248560 (SEQ ID NO:5) and NW0249392 (SEQ ID NO:12 on LG7;   loci NW0248392 (SEQ ID NO:6) and NW0248268 (SEQ ID NO:13) on LG10; or   loci NW0248711 (SEQ ID NO:7) and NW0248268 (SEQ ID NO:13) on LG10;   or within 15 cM thereof.   
     
     
         8 . A part of the watermelon plant of  claim 1 , further defined as pollen, an ovule, a leaf, an embryo, a root, a root tip, an anther, a flower, a fruit, a stem, a shoot, a seed, a protoplast, a cell, and a callus. 
     
     
         9 . The part of the watermelon plant of  claim 8 , wherein the part is a seed. 
     
     
         10 . A method of detecting in at least one watermelon plant a genotype associated with a desired sex expression phenotype, the method comprising the step of: (i) detecting in at least one watermelon plant an allele of at least one polymorphic nucleic acid that is associated with a desired sex expression phenotype, wherein the polymorphic nucleic acid is in or genetically linked to a genomic region defined by:
 loci NW0248967 (SEQ ID NO:1) and NW0248118 (SEQ ID NO:3) on linkage group 2 (LG2), or within 15 cM thereof;   loci NW0252278 (SEQ ID NO:4) and NW0248560 (SEQ ID NO:5) on linkage group 7 (LG7), or within 15 cM thereof   loci NW0248392 (SEQ ID NO:6) and NW0248711 (SEQ ID NO:7) on linkage group 10 (LG10), or within 15 cM thereof; or   loci NW0249365 (SEQ ID NO:8) and NW0250112 (SEQ ID NO:9) on linkage group 11A (LG11A), or within 15 cM thereof.   
     
     
         11 . The method of  claim 10 , further comprising the step of: (ii) selecting at least one watermelon plant in which a genotype associated with a desired sex expression phenotype has been detected. 
     
     
         12 . The method of  claim 10 , wherein the polymorphic nucleic acid is located in a genomic region flanked by:
 loci NW0248967 (SEQ ID NO:1) and NW0251455 (SEQ ID NO:11) on LG2;   loci NW0248118 (SEQ ID NO:3) and NW0251455 (SEQ ID NO:11) on LG2;   loci NW0252278 (SEQ ID NO:4) and NW0249392 (SEQ ID NO:12 on LG7;   loci NW0248560 (SEQ ID NO:5) and NW0249392 (SEQ ID NO:12 on LG7;   loci NW0248392 (SEQ ID NO:6) and NW0248268 (SEQ ID NO:13) on LG10; or   loci NW0248711 (SEQ ID NO:7) and NW0248268 (SEQ ID NO:13) on LG10;   or within 15 cM thereof.   
     
     
         13 . A method for producing a watermelon plant that comprises in its genome at least one locus associated with a desired sex expression phenotype, the method comprising:
 (i) crossing a first watermelon plant lacking a locus associated with a desired sex expression phenotype with a second watermelon plant comprising a locus associated with a desired sex expression phenotype defined by:   loci NW0248967 (SEQ ID NO:1) and NW0248118 (SEQ ID NO:3) on linkage group 2 (LG2), or within 15 cM thereof;   loci NW0252278 (SEQ ID NO:4) and NW0248560 (SEQ ID NO:5) on linkage group 7 (LG7), or within 15 cM thereof;   loci NW0248392 (SEQ ID NO:6) and NW0248711 (SEQ ID NO:7) on linkage group 10 (LG10), or within 15 cM thereof; or   loci NW0249365 (SEQ ID NO:8) and NW0250112 (SEQ ID NO:9) on linkage group 11A (LG11A), or within 15 cM thereof;   (ii) detecting in progeny resulting from said crossing at least a first polymorphic locus in or genetically linked to said locus associated with a desired sex expression phenotype; and   (iii) selecting a watermelon plant comprising said polymorphism and said locus associated with a desired sex expression phenotype.   
     
     
         14 . The method of  claim 13 , further comprising the step of:
 (iv) crossing the watermelon plant of step (iii) with itself or another watermelon plant to produce a further generation.   
     
     
         15 . The method of  claim 14 , wherein steps (iii) and (iv) are repeated from about 3 times to about 10 times. 
     
     
         16 . The method of  claim 13 , wherein the desired sex expression phenotype is selected from the group consisting of percent male flowers, percent female flowers, percent hermaphroditic flowers, and percent female of total pistillate flowers. 
     
     
         17 . The method of  claim 13 , wherein the polymorphic nucleic acid is located in or genetically linked to a genomic region defined by:
 loci NW0248967 (SEQ ID NO:1) and NW0251455 (SEQ ID NO:11) on LG2;   loci NW0248118 (SEQ ID NO:3) and NW0251455 (SEQ ID NO:11) on LG2;   loci NW0252278 (SEQ ID NO:4) and NW0249392 (SEQ ID NO:12 on LG7;   loci NW0248560 (SEQ ID NO:5) and NW0249392 (SEQ ID NO:12 on LG7;   loci NW0248392 (SEQ ID NO:6) and NW0248268 (SEQ ID NO:13) on LG10; or   loci NW0248711 (SEQ ID NO:7) and NW0248268 (SEQ ID NO:13) on LG10;   or within 15 cM thereof.   
     
     
         18 . A method of watermelon plant breeding, the method comprising the steps of:
 (i) selecting at least a first watermelon plant comprising at least one allele of a polymorphic nucleic acid that is in or genetically linked to a QTL associated with a desired sex expression phenotype, wherein the QTL maps to a position between   loci NW0248967 (SEQ ID NO:1) and NW0248118 (SEQ ID NO:3) on LG2;   loci NW0252278 (SEQ ID NO:4) and NW0248560 (SEQ ID NO:5) on LG7;   loci NW0248392 (SEQ ID NO:6) and NW0248711 (SEQ ID NO:7) on LG10; or   loci NW0249365 (SEQ ID NO:8) and NW0250112 (SEQ ID NO:9) on LG11A; and   (ii) crossing the first watermelon plant with itself or a second watermelon plant to produce progeny watermelon plants comprising the QTL associated with a desired sex expression phenotype.   
     
     
         19 . The method of  claim 18 , wherein the desired sex expression phenotype comprises one or more traits selected from the group consisting of percent male flowers, percent female flowers, percent hermaphroditic flowers, and percent female of total pistillate flowers. 
     
     
         20 . The method of  claim 18 , wherein the QTL maps to a position between:
 loci NW0248967 (SEQ ID NO:1) and NW0251455 (SEQ ID NO:11) on LG2;   loci NW0248118 (SEQ ID NO:3) and NW0251455 (SEQ ID NO:11) on LG2;   loci NW0252278 (SEQ ID NO:4) and NW0249392 (SEQ ID NO:12 on LG7;   loci NW0248560 (SEQ ID NO:5) and NW0249392 (SEQ ID NO:12 on LG7;   loci NW0248392 (SEQ ID NO:6) and NW0248268 (SEQ ID NO:13) on LG10; or   loci NW0248711 (SEQ ID NO:7) and NW0248268 (SEQ ID NO:13) on LG10;   or within 15 cM thereof.   
     
     
         21 . The method of  claim 18 , wherein at least one polymorphic nucleic acid that is genetically linked to a QTL associated with a desired sex expression phenotype maps within 40 cM, 20 cM, 15 cM, 10 cM, 5 cM, or 1 cM of the QTL associated with a desired sex expression phenotype. 
     
     
         22 . A method of introgressing an allele into a watermelon plant, the method comprising:
 (i) genotyping at least one watermelon plant in a population with respect to at least one polymorphic nucleic acid located in or genetically linked to a genomic region defined by
 loci NW0248967 (SEQ ID NO:1) and NW0248118 (SEQ ID NO:3) on linkage group 2 (LG2), or within 15 cM thereof; 
 loci NW0252278 (SEQ ID NO:4) and NW0248560 (SEQ ID NO:5) on linkage group 7 (LG7), or within 15 cM thereof; 
 loci NW0248392 (SEQ ID NO:6) and NW0248711 (SEQ ID NO:7) on linkage group 10 (LG10), or within 15 cM thereof; or 
 loci NW0249365 (SEQ ID NO:8) and NW0250112 (SEQ ID NO:9) on linkage group 11A (LG11A), or within 15 cM thereof; 
   (ii) selecting from the population at least one watermelon plant comprising at least one allele associated with a desired sex expression phenotype.   
     
     
         23 . The method of  claim 22 , wherein the desired sex expression phenotype comprises one or more traits selected from the group consisting of percent male flowers, percent female flowers, percent hermaphroditic flowers, and percent female of total pistillate flowers. 
     
     
         24 . The method of  claim 22 , wherein the polymorphic nucleic acid is located in a genomic region flanked by:
 loci NW0248967 (SEQ ID NO:1) and NW0251455 (SEQ ID NO:11) on LG2;   loci NW0248118 (SEQ ID NO:3) and NW0251455 (SEQ ID NO:11) on LG2;   loci NW0252278 (SEQ ID NO:4) and NW0249392 (SEQ ID NO:12 on LG7;   loci NW0248560 (SEQ ID NO:5) and NW0249392 (SEQ ID NO:12 on LG7;   loci NW0248392 (SEQ ID NO:6) and NW0248268 (SEQ ID NO:13) on LG10; or   loci NW0248711 (SEQ ID NO:7) and NW0248268 (SEQ ID NO:13) on LG10;   or within 15 cM thereof.   
     
     
         25 . A watermelon plant obtained by the method of  claim 22 .