This tutorial describes how to design an F2 nursery with checks.
- Start a New Nursery
- Collect Trait Data & Make Selections
- Advance by Single Plant Selection to F3
Start a New Nursery
- From Manage Studies tool, select Start a New Study.
- Name and describe the F2 Nursery.
- Add the name of the investigator using the Add function in the STUDY SETTINGS.
Nursery details can also be configured by choosing a previously saved nursery template if necessary.
Add Selection Unit & Traits
The F2 Nursery will be advanced by selection of entries based on disease resistance ratings. Unit of selection should be added to the nursery settings.
- Add the units of selection (number of ears selected) using the Add function associated with SELECTION. Several Selection criteria are available.
- Selection: Identify Number of ears Selected (nEarSel)
- Save the Nursery.
Germplasm & Checks
The F2 nursery will have check entries in addition to the entries of F2 germplasm. We will prepare a new germplasm list combining the F2 entry list and the nursery check entry list.
- From Manage Germplasm, browse for the F2 germplasm list.
- Select the F2 Germplasm list.
- Browse for the Nursery checks list and select.
Both F2 Germplasm list and Nursery checks list appear in two different tabs.
- Select the Show List Builder icon.
A blank Entry list is generated by the List Builder tool.
- Select all 25 F2 Germplasm entries and drag and drop them to the new list.
- From the Nursery Checks tab, select the three check entries and drag and drop to the new list.
Notice that the new list now has a total of 28 entries.
- Describe the list details and save the new germplasm list that contains F2 germplasm entries and check entries in the 2018 folder.
- From the Manage Studies tool, Browse for the saved F2 nursery and Open
- From the Germplasm and Checks tab, browse for the newly created F2 germplasm and checks list and Select.
- Scroll to the last three entries that were selected from the nursery check list
- In the Entry Type column, click on the Test Entry and change each of the three entries from Test entry to Check entry.
Confirm that the three check entries are listed as Check entries in the F2 nursery list.
- From the Environment tab, select the location name as Default breeding location.
- From the Experimental Design tab, select Entry list order as the design type.
- Specify the Design Parameters for Checks.
- Starting position of checks 1
- Spacing - 9 entries between checks
- Manner of insertion - Select Insert each check in turn.
- Select Generate Design and Save.
The Measurement tab is now populated. The Entry Type column identifies the Check and Test entries and the the selection parameter identified (nEarsSel) is present as a column heading.
The F2 Nursery entries would be evaluated for resistance to Downy mildew. Notice that TRAITS selection tool is available to select Downy mildew severity.
- Select Add associated with TRAITS and type downy to select Downy mildew severity (DMSev_E_1to5) from the drop down.
Downy Mildew severity will be measured on a 1 to 5 scale.
The Measurement tab now has an added column for data collection with the heading DMSev_E_1to5 for downy mildew severity.
- Save the nursery.
The F2 nursery is now available for the following activities. (For brevity this tutorial skips activities 1-3, which were covered in previous tutorials).
- Make labels for nursery plots
- Make labels for seed withdrawal
- Field mapping
- Export of nursery book for data collection
Collect Trait Data & Make Selections
Export Nursery Book
- Export Study book from the Data collection options of the Actions menu.
- Choose Excel (.xls) as the export format with data collected in plot order. Export the .xls file to your computer.
- Open the Excel file and review. The observation sheet has two empty columns for data collection for Downy mildew severity and the number of ears selected for each entry. The Checks are identified as C and the Test entries as T in the Entry type colum.
The file below has hypothetical data collected for Downy mildew severity and the number of ears selected from entries preferred by the breeder after making observations during the season.
- Copy the data present in the last two columns in the file below into the Excel file that was saved on your computer and save.
- Select Import Measurements from the Data collection options of the Actions menu.
- Browse for the saved Excel file with data and import.
- Review the imported data and Save.
Advance by Single Plant Selection to F3
These Selections that were made on individual F2 populations will be advanced to F3s.
- Select Advance Study from the Advance study option from the Actions menu.
- Select Continue
- Ears selected correspond to individual F2 plants. Choose the single plant selection breeding method. Since different numbers of lines are selected from each F2 population plots, deselect the box specifying Same number of lines selected for each plot and choose the selection unit, nEarSel. Identify the Harvest Location.
- Select Finish and review the pending F3 lines.
- Select Finish after review and name, describe, and save the F3 Germplasm list.
Harvest F3 Seed
- Select Generate Stock List from Advanced List Actions to record the amount of seed harvested.
- Select the check box at the top of the table to highlight all entries. Select Update Inventory from the Stock List Actions.
- Specify storage location, g -weighed, and amount of 150 for all entries. Save the nursery.
Review Germplasm Details
150 grams of seed has now been applied to all 267 F3 germplasm entries.
Harvesting the exact same amount of seed from each cross may not be realistic. To record individual amounts, you have the option to exporting the stock list (.xls), enter individual values per entry and import the stock list.
- Select 1B1-RB-1 to review germplasm details.
- Notice that the correct breeding method, Single plant selection, was applied in the creation of this germplasm.
- Select the box next to 'Include derivative and maintenance lines' and select View Pedigree Graph from Pedigree Tree.
Pedigree graph of generative methods connects the F3 germplasm to the original crosses.
- Select the box - Include derivative and maintenance lines and select Display.
Pedigree graph of derivative and maintenance lines connects the F3 germplasm to the F2 and F1 lines.
The Integrated Breeding Platform (IBP) is jointly funded by: the Bill and Melinda Gates Foundation, the European Commission, United Kingdom’s Department for International Development, CGIAR, the Swiss Agency for Development and Cooperation, and the CGIAR Fund Council. Coordinated by the Generation Challenge Program the Integrated Breeding Platform represents a diverse group of partners; including CGIAR Centers, national agricultural research institutes, and universities.
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