Can we readily expect homozygous knockouts in the T0 plants in CRISPR knockout event of tomato plants? Or should we wait until the T1 plants after the selfing event?
Yes it is possible. I have found many homozygous knockouts in the T0 generation in rice crop. But is always better to go for T1 generation to have more robust results.
Yes. Quite a few genome-editing plant species have shown that homozygous knockouts can be obtained at T0 generation, especially for diploid (2N) plant species. For polyploidy, it is still possible but the number of plants will be less. For example, 4 alleles of gene(s) of 4N potato has been knocked out.