Hilchos Maaser Sheini and Neta Revai 11:14

If someone only has second tithe, he still recites the tithe confession. This is because the main concern of the confession is second tithe. Similarly, if one only has first fruits, he recites the tithe confession because the aforementioned verse (Deut. 26:13) says: “I removed the holy things” and the first holy thing is the first fruits. However, if someone only has terumah, he doesn’t recite the confession. This is because terumah doesn’t require the confession except in the context of the other agricultural gifts.

Hilchos Maaser Sheini and Neta Revai 11:15

The verse continues: “I did not transgress your commandments.” This means that he didn’t separate tithes from one type of produce for another, nor from harvested produce for produce that is still connected to the ground, nor vice versa, nor from this year’s produce for last year’s, nor vice versa. “I did not forget” means that he didn’t neglect to bless Hashem and to recount His name when taking these gifts. “I didn’t eat of it in a state of bereavement” teaches us that one who eats of it in a state of bereavement doesn’t recite the declaration. “I didn’t remove it in a state of ritual impurity” teaches us that one who separated it in a state of ritual uncleanliness doesn’t recite the declaration. “I didn’t give from it to the dead” teaches us that he didn’t use the money from redeeming tithes to purchase a casket or shrouds, nor did he give it to other mourners. “I listened to the voice of Hashem my God,” means that he brought it to the Temple. “I acted according to all that You commanded me” means that he and others rejoiced in it as per Deuteronomy 26:11: “You share rejoice in all the good.”