In search of.... Better disease resistance

Fusion_power · July 18, 2020

My tomato plants have been wiped out by septoria, gray mold, early blight, and sometimes late blight every time I've grown tomatoes for the last 35 years. So what did I do? I searched for better disease resistance by growing countless hybrids, tons of open pollinated disease resistant tomatoes, and eventually delving into germplasm from TGRC. In 2011, I grew a range of TGRC lines with the intent of finding something that could combat the intense disease pressure in my garden. I found 3 plants with better than normal leaf disease tolerance. LA2175 and LA2869 are both S. Habrochaites which means a LOT of work required to move the disease resistance into a domestic tomato background. I'm still working with these, but it is definitely a long term project. LA0417 (S. Pimpinellifolium) was unusual in that one single plant out of about a dozen showed significantly better resistance.

I saved seed from that single plant (pollen) and crossed it to Piennolo (female stigma). This was a relatively easy cross as Piennolo is potato leaf while LA0417 is regular leaf. The next year I grew out the regular leaf offspring and started selecting. I'm up to 4 generations now and have some decent results. There are 4 hybrid plants in my garden. All are potato leaf, all are resistant to foliage disease, all are the size of large cherries in the 1 inch diameter range. 3 of the 4 plants have slight nipples inherited from Piennolo. All 4 plants carry the genes for long shelf life. One of the plants shows susceptibility to early tissue necrosis in the fruit, probably a result of insect damage. One plant has not yet matured fruit though it should within the next week. All of the fruit taste good to very good though they are admittedly not as good as the best heirlooms such as Brandywine or Cherokee Purple.

Now the $64,000 question. If I make seed available from the best plant(s), would you be interested in growing a good flavored large cherry size tomato that has outstanding disease resistance to southern heat and humidity?

July 18, 2020	#1
Fusion_power Tomatovillian™ Join Date: Feb 2006 Location: Alabama Posts: 2,250	In search of.... Better disease resistance My tomato plants have been wiped out by septoria, gray mold, early blight, and sometimes late blight every time I've grown tomatoes for the last 35 years. So what did I do? I searched for better disease resistance by growing countless hybrids, tons of open pollinated disease resistant tomatoes, and eventually delving into germplasm from TGRC. In 2011, I grew a range of TGRC lines with the intent of finding something that could combat the intense disease pressure in my garden. I found 3 plants with better than normal leaf disease tolerance. LA2175 and LA2869 are both S. Habrochaites which means a LOT of work required to move the disease resistance into a domestic tomato background. I'm still working with these, but it is definitely a long term project. LA0417 (S. Pimpinellifolium) was unusual in that one single plant out of about a dozen showed significantly better resistance. I saved seed from that single plant (pollen) and crossed it to Piennolo (female stigma). This was a relatively easy cross as Piennolo is potato leaf while LA0417 is regular leaf. The next year I grew out the regular leaf offspring and started selecting. I'm up to 4 generations now and have some decent results. There are 4 hybrid plants in my garden. All are potato leaf, all are resistant to foliage disease, all are the size of large cherries in the 1 inch diameter range. 3 of the 4 plants have slight nipples inherited from Piennolo. All 4 plants carry the genes for long shelf life. One of the plants shows susceptibility to early tissue necrosis in the fruit, probably a result of insect damage. One plant has not yet matured fruit though it should within the next week. All of the fruit taste good to very good though they are admittedly not as good as the best heirlooms such as Brandywine or Cherokee Purple. Now the $64,000 question. If I make seed available from the best plant(s), would you be interested in growing a good flavored large cherry size tomato that has outstanding disease resistance to southern heat and humidity? Last edited by Fusion_power; July 18, 2020 at 12:15 PM.