פירוש על עוקצים 1:2

והקפלוטות (leeks with a head, torret) – leeks, a חציר /leek (Numbers 11:5) in the language of Scripture, KORAHT in Arabic, and the foreign language PORUSH.

Roots of garlic, onions or leeks that are still moist, or their top-parts, whether they are moist or dry, also the central stalk that is within the edible part, the roots of lettuce, the radish and the turnip, the words of Rabbi Meir.
Rabbi Judah says: only the large roots of the radish are included, but its fibrous roots are not included.
The roots of the mint, rue, wild herbs and garden herbs that have been uprooted in order to be planted elsewhere, and the spine of an ear of grain, and its husk.
Rabbi Elazar says: also the earth covering of roots;
All these things contract and convey impurity and are included.
Today's mishnah discusses what parts of certain types of produce are considered to be part of the plant.
Sections one through four: In these four sections, various tannaim determine what parts of certain types of produce, specifically the roots and the spines/stalks of root vegetables, count as being part of the produce. In general roots are part of the plant if they will either be eaten or if they will be used for replanting. Inedible roots are not part of the produce. So too other parts of the produce, and even the dirt accompanying the produce according to Rabbi Elazar, count with the produce if they are necessary to it. I think that most of these are fairly clear from the translation, so I won't explain each one on its own.
Section five: All of the parts of produce that are listed above do three things: they contract impurity if the rest of the piece of produce was defiled. If they are defiled they convey their impurity to the other part. Finally, they are reckoned with the remainder of the produce to constitute the requisite amount to become impure.

והפטמא שלהן (and their protuberance on the blossom-end of fruits – having the appearance of a pestle seated in a mortar – the upper portion of the fruit/top-piece) – like a kind of top-piece of a pomegranate that is at their top. And it is a protector and it combines.

והעמוד שהוא מכוון כנגד האוכל (the scape/central stalk as far as it is surrounded by the edible part, the scape within the bulb) – which is the heart that is in the onion, that the seed is born at its end.

שרשי החזרים – the root of lettuce, which is חסא in the language of the Gemara and also in Arabic, and LETUGA in the foreign language.

והנפוס (a kind of radish, resembling the carrot as to foliage, and the radish as to taste, or a turnip) – It is a kind of radish, but its leaves are similar to the leaves of the turnip.

והסיב שלו (and the fibrous root of the radish) – Maimonides explained that on the side of the top of the radish are born thin sinews like threads, and the sellers sever/cut them by hand at the time that they sell them, and what remains of them are called סיב/fibrous roots of the radish.

והמיתנא (and the mint) – such is its name in the foreign tongue MUNTA, and NANA in Arabic.

והפיגום (rue) – RUDA in the foreign tongue, and in Arabicv SARAV.

שעקרן (which were uprooted)- in order to plant them in another place.

והשדרה של שבולת (and the spine of an ear of corn) – the middle thread, that the threads are attached to it.

והלבוש שלה (the husk of the wheat grain) – and the skin/membrane that is upon the seed of the wheat, and all of these are protections for the fruit.

הסיג של רצפות (the cobweb-like covering of fruits) – dust that is attached on the heads of vegetables and joined closely on them like the spider’s web. ASnd it also is considered a protection to the fruit. But the Halakha is not according to Rabbi Eliezer.