1) The document summarizes a student's research on self-compatibility in tomatillos. The student tracked pollination methods and outcomes over multiple greenhouse visits. 2) An unexpected cold snap compromised early crosses and weakened pistils. This led to many failed pollinations and the loss of collected data. 3) In the final visit, the student's plant was accidentally destroyed before final pollinations could be completed, resulting in an incomplete study and lack of results. The student was only able to use limited data from a classmate's successful plant.

1. Self compatibility in Physalis peruvianum
(Tomatillo)
Matt Wildenauer
Hort 4401: Plant Genetics & Breeding

2. LAB NOTES
Tomatillo
Matthew Wildenauer
Introductory notes and observations: Assigned to group #1 with Marco Bosse and Jennifer LaValley.
Jennifer and I chose verde (green) tomatillo plants and Marco selected a purple tomatillo plant. I se-
lected my plant based on its early growth habit, I didn’t want a plant that was too wide or one that is
too tall or tree-like. I selected a strong, bushy tomatillo and began executing the study. Branches were
labeled and organized as so...
1) Self Pollination branch: This branch is dedicated to self pollination crosses
2) Cross Pollination branch: This branch is used for crossing with partners purple/verde plants
3) Pollen Source branch: This branch serves as a pollen source for group member’s crosses
4) Open Pollinated Control: Nothing is done to this branch
5) Select a branch and bag it with thin mesh, this ensures this branch will not be pollinated.
Details:
- Small white tags were created and labeled in order to monitor and keep track of pollinations
- Tags were labeled with pollination method, color, initials of cross participants and date.
- In order to keep better organization, tags were color coordinated on the back with marker
- In order to pollinate, flowers are first emasculated by first removing the sepals, then the petals
(carefully) and lastly the stamen. This leaves only the pistil (female organ) and allows the flower to be
pollinated for fruit production.
- To pollinate, anthers with high amounts of pollen were selected. These anthers were plucked from
the flower with tweezers and gently rubbed against the pistil. This ensures efficient and visible polli-
nation transfer.
Challenges: This research process faced some debilitating challenges throughout the study...
- Greenhouse malfunction allowing temperature in tomatillo room to drop to only 34 degrees
Fahrenheit. This had a direct impact on many of the plants and created issues that persisted.
- Strength of pistils seemed to be very low, many pistils were knocked off during even the
most gentle of emasculations. This caused not only disappointment but also frustration.
When you waste time and lose 5-6 crosses every visit, it definitely wears you down.
- All crosses before the cold snap were compromised. All crosses fell off the branches and were
no longer identifiable. Crosses performed after the cold snap did not have enough time to
produce fruit.
- A large amount of delayed pollinations/early emasculations fell off the plant in between wait
times (2-4 days)

3. LAB NOTES
Tomatillo
Matthew Wildenauer
February 12, 2015: first attempts and crosses
Self cross: 3 Attempted emasculations: 10
Verde x Verde (JL): 1 Successful emasculations: 5
Verde x Purple (MB): 1 Pistils lost: -5
Notes:
*No early emasculations/delayed pollination
*First attempts resulted in many failed emasculations, likely user error as I was still getting a hang of
the process and pistil sensitivity.
February 13, 2015: checking to see if potential flowers were ready for emasculation
Self cross: 2 Attempted emasculations: 6
Verde x Verde (JL): 1 Successful emasculations: 3
Verde x Purple (MB): none Pistils lost: -3
Notes:
*No early emasculations/delayed pollination
*Low number of crosses due to lack of available pollen sources from partner plants. Many flowers
were present but few were open yet. The three failed emasculations were due to impatience.
February 16, 2015: Beginning of early emasculation/ late pollination attempts
Self cross: 3 Attempted emasculations: 15
Verde x Verde (JL): 2 normal, 2 early Successful emasculations: 11
Verde x Purple (MB): 2 normal, 2 early Pistils lost: -4
Notes:
*Most succesful day thus far, flowers were prolific and easier than usual to emasculate
*Early emasculations were successfull and will be pollinated during the next greenhouse visit (2/19)
*Plant was staked in several areas as it continues to grow, leaves look very healthy and growth habit
has maintained original form preference.

4. LAB NOTES
Tomatillo
Matthew Wildenauer
February 19, 2015: Continued progress and first signs of negative health
Self cross: 2 Attempted emasculations: 11
Verde x Verde (JL): 2 normal, 2 early Successful emasculations: 9
Verde x Purple (MB): 2 normal, 1 early Pistils lost: -2
Notes:
*Early attempts from 2/16 were pollinated accordingly
*Highest success rate for emasculations so far, only lost 2 pistils. This despite the fact that the soil was
bone dry along with the majority of others. Leaves were soft and wilted, increased watering needed.
A temperature drop occurred on 2/17 and likely contributed to general lack of plant vigor.
February 23, 2015: Doomsday
Self cross: 1 Attempted emasculations: 10
Verde x Verde (JL): none Successful emasculations: 1
Verde x Purple (MB): none Pistils lost: -9
Notes:
* Almost no successful crosses, despite many attempts. Pistils became extremely sensitive and were
knocked off with only the slightest touch.
* Confirmation that greenhouse temperature dropped to 34 degrees Fahrenheit on 2/17/15
February 23, 2015: Additional notes
* While the effect of a greenhouse temperature malfunction wasn’t devastating in the early assess-
ments, after one week the plant has now shown severe consequences. All previous crosses have been
compromised. The pistil/flower remnants were missing from every cross tag and some crosses were
seen laying in the pot. The cold snap undoubtedly caused the plant to drop pollinated flowers, this
could be an effect of the plant reserving energy to recover from the temperature drop.
*I found it interesting that the plants health recovered quickly and only mild wilting occurred after
the initial exposure. The plants flowers and pistils were very weak (entire flowers were falling off
when bumped)but the plant itself looked healthy and vigorous. This may be some sort of natural
“reset” button, discarding early fruiting efforts and allowing the plant to survive and recover.

5. LAB NOTES
Tomatillo
Matthew Wildenauer
March 2, 2015: Final cross attempts, project moral quite low after losing crosses
Self cross: 1 Attempted emasculations: 9
Verde x Verde (JL): zero normal, 2 early Successful emasculations: 7
Verde x Purple (MB): 1 normal, 3 early Pistils lost: -2
Notes:
*This session of crosses was purely to fulfill the requirements of the procedure. No fruits are expected
this late in the process.
*Early emasculations will be pollinated on 3/5
March 5, 2015: Experiment failure
*When going in to complete the final pollinations, I found my plant crushed and broken. Another
large tomatillo plant that was bearing fruit, broke and landed on my plant. This cause my plant to fall
and all major branches were broken and useless. Therefore, I was unable to collect the necessary data
to complete this reproductive experiment.
*Plant was thrown into compost, tags were removed and the plastic pot was added to the pot recy-
cling . All tags were checked during removal to confirm there was no information being missed.
Support:
While a few individuals had fruit production, many classmates did not. Therefore, much of the infor-
mation that will be used for this report comes from the shared fruit information of a classmate. My
group only had a couple very small fruits so we used the information of Matt Ng. I personally dis-
sected and counted the fruit and seeds for his open-pollination branch. Matt’s plant ended up being
one of the best producers of fruit and seed in class.