# US 8,772,582 B2 · Methods for plant seed production > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,772,582 B2 - Document ID: US8772582B2 - Status: Granted - Kind: B2 - Application number: 12/549,259 - Filed: 2009-08-27 - Published: 2010-03-04 - Granted: 2014-07-08 - Earliest claimed: 2008-08-29 - Assignees: Seminis Vegetable Seeds, Inc. - Applicants: Benito Juarez; Terry Walker; Fred McCuistion; Greg Tolla - Inventors: Benito Juarez; Terry Walker; Fred McCuistion; Greg Tolla - Web page: https://patentgrep.com/patent/US8772582B2 ## CPC - A01H 1/021: {Methods of breeding using interspecific crosses, i.e. interspecies crosses} - A01G 2/30: Grafting (grafting-wax A01N3/04) - A01G 22/05: Fruit crops, e.g. strawberries, tomatoes or cucumbers - A01H 1/04: Processes of selection {involving genotypic or phenotypic markers; Methods of using phenotypic markers for selection} - A01H 1/08: Methods for producing changes in chromosome number - A01H 5/08: Fruits - A01H 6/342: {Citrullus lanatus [watermelon]} - Y02A 40/10: in agriculture - A01H: NEW PLANTS OR {NON-TRANSGENIC} PROCESSES FOR OBTAINING THEM; PLANT REPRODUCTION BY TISSUE CULTURE TECHNIQUES - A01G: HORTICULTURE; CULTIVATION OF VEGETABLES, FLOWERS, RICE, FRUIT, VINES, HOPS OR SEAWEED; FORESTRY; WATERING (picking of fruits, vegetables, hops or the like A01D46/00; propagating unicellular algae C12N1/12) - Y02A: TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE ## Abstract The invention provides methods for producing seeds in watermelon. In one embodiment methods are provided comprising grafting of a seed parent onto a stress tolerant rootstock, pollinating the seed parent with pollen from a pollen donor, and cultivating the seed parent until seed is formed. In specific embodiments, triploid seeds produced by a method of the invention are rendered conspicuously distinguishable from tetraploid seeds, and thus readily selected manually or by an automated machine. Methods for increasing seed yield and/or quality are also provided. ## Claims ### Claim 1 A method of producing triploid watermelon seed comprising: (a) obtaining a tetraploid watermelon plant, wherein the plant has been grafted onto a rootstock that exhibits stress tolerance when under stress conditions; (b) allowing the tetraploid watermelon plant to be pollinated by a diploid watermelon plant; and (c) allowing triploid seed to form on the tetraploid watermelon plant. ### Claim 2 (depends on 1) The method of claim 1, wherein the stress tolerance comprises an abiotic stress tolerance selected from the group consisting of cold tolerance, high temperature tolerance, drought tolerance, and salt tolerance. ### Claim 3 (depends on 1) The method of claim 1, wherein the stress tolerance comprises a biotic stress tolerance selected from the group consisting of a disease resistance, an insect resistance, and a nematode resistance. ### Claim 4 (depends on 1) The method of claim 1, wherein the rootstock is from a plant selected from the group consisting of watermelon, squash, pumpkin, wax gourd, and bottle gourd. ### Claim 5 (depends on 1) The method of claim 1, wherein the diploid watermelon plant is grafted onto a rootstock that exhibits stress tolerance when under stress conditions. ### Claim 6 (depends on 1) The method of claim 1, wherein the diploid watermelon plant has not been grafted. ### Claim 7 (depends on 1) The method of claim 1, further comprising the step of: (d) selecting the triploid seed from a population of seed resulting from step (c) based on the thickness and/or weight of the triploid seed. ### Claim 8 (depends on 1) The method of claim 1, wherein the tetraploid watermelon plant is grown in the absence of said stress conditions. ### Claim 9 (depends on 1) The method of claim 1, wherein the tetraploid watermelon plant is grown in the presence of said stress conditions. ### Claim 10 (depends on 1) The method of claim 1, wherein the stress tolerance comprises a biotic stress tolerance selected from the group consisting of viral disease resistance, bacterial disease resistance, and fungal disease resistance. ### Claim 11 (depends on 7) The method of claim 7, wherein the step of selecting is performed manually. ### Claim 12 (depends on 7) The method of claim 7, wherein the step of selecting is automated. ### Claim 13 (depends on 1) The method of claim 1, wherein the tetraploid watermelon plant is pollinated by an insect. ### Claim 14 (depends on 1) The method of claim 1, wherein the tetraploid watermelon plant is hand-pollinated. ### Claim 15 (depends on 1) The method of claim 1, wherein the grafting is performed by a method selected from the group consisting of splice grafting, bud grafting, cleft grafting, side grafting, approach grafting, and hole insertion grafting. ### Claim 16 (depends on 1) The method of claim 1, wherein the triploid watermelon seed formed in step (c) exhibits a morphology that is distinguishable from tetraploid seed produced by the seed parent. ### Claim 17 (depends on 1) The method of claim 1, wherein the tetraploid watermelon plant produces a greater number of seed per fruit and/or with a higher degree of hybridity relative to a watermelon plant of the same genotype as said tetraploid watermelon plant that has not been grafted and is grown under the same conditions as the tetraploid watermelon plant. ### Claim 18 (depends on 1) The method of claim 1, wherein the tetraploid watermelon plant is exposed to at least a first biotic and/or abiotic stress prior to triploid seed forming. ### Claim 19 A population of watermelon plants planted in pollinating proximity in a field comprising: (a) tetraploid watermelon seed parent plants, wherein the plants have been grafted onto a rootstock that exhibits stress tolerance when under stress conditions; and (b) diploid watermelon pollen donor plants. ### Claim 20 (depends on 19) The population of claim 19, wherein the tetraploid watermelon seed parent plants and diploid watermelon pollen donor plants are planted in alternating rows. ### Claim 21 (depends on 20) The population of claim 20, wherein the rows are planted in a ratio of rows comprising tetraploid watermelon seed parent plants to diploid watermelon pollen donor plants of 1:1, 2:1, 3:1, 4:1 or 5:1.