The morphological characteristics of inflorescences are preserved in the bunches that develop from them. The lower part of the central axis of the bunch (from the point of attachment to the shoot to the origin of the first lateral branch) is called the "peduncle" of the bunch, while the entire system of lateral branchings of the 1st, 2nd, and 3rd orders is called the "rachis." The pedicels of the berries are attached to the ultimate branchings of the rachis.
The peduncle of the bunch is initially green and herbaceous, but by the time the berries ripen, its tissues begin to lignify to a greater or lesser extent, after which it acquires extraordinary strength and breaks with great difficulty. The only point on the peduncle of the bunch that retains its fragility until the end is the node from which the tendril originates (Fig. 40). In some bunches, this tendril dries up and sheds shortly after flowering; in others, it persists even after the berries ripen; finally, in a third group, it transforms into a small secondary bunch, resulting in the formation of so-called "shouldered" (winged) bunches. There are grapevine cultivars in which the bunches appear almost double, as the "shoulder" formed from the tendril is nearly equal to the main bunch in terms of development and the number of berries (e.g., in Rkatsiteli, Korinka Belaya, etc.). The degree of peduncle lignification also varies greatly among different grapevine cultivars.
The bunch type, i.e., its general shape and density, ultimately depends on the relative development of all the branchings of the rachis. If these branchings are poorly developed, the bunch will be more or less cylindrical and compact (Fig. 40); if the primary branchings of the rachis are more strongly developed, while the subsequent ones develop weaker and weaker toward the tip of the bunch, the latter acquires a conical shape; finally, if the lateral branchings of the rachis are of considerable length, the bunch becomes branched and very loose. In conical and branched bunches, the distinct secondary branches are referred to as "shoulders" (lobes) (Fig. 40).
The density of the bunches also varies greatly: in some cases, the berries are packed so tightly that they press against one another and deform (i.e., acquire an irregular, polygonal shape); in other cases, they sit more loosely on the branchings of the rachis. In cultivars with functionally female flowers under difficult cross-pollination conditions, it is not uncommon for only solitary berries to develop on long branchings of the rachis, situated at a considerable distance from one another.
All these bunch characteristics define specific grapevine cultivars quite well (for instance, small, cylindrical, compact bunches are typical for the Pinot Franc cultivar; huge, branched, loose bunches are characteristic of the Nimrang cultivar, etc.), although one must not overlook the fact that the bunch "type" changes significantly depending on environmental conditions, as well as on the conditions under which flowering and pollination occurred in a given growing season.
