Rootstock deriving from the cross of Vitis vinifera cv, Chasselas B and Vitis berlandieri. Today there are 15 different clones of this rootstock: 80, 86, 87, 88, 153, 172, 193, 194, 195, 210, 212, 231, 232, 233, 238.

41 MGT B tolerance the root form of phylloxera is moderate to high. It is also a rootstock susceptible to the nematodes Meloidogyne incognita, Meloidogyne arenaria and Meloidogyne hapla and appears susceptible to Agrobacterium Vitis.

41B is known by its adaptation to limestone soils and its tolerance to chlorosis. Up to 60% tolerant to total calcium and 40% to active calcium and CCI * (see R 110) up to 60. It also absorbs magnesium from the soil quite well. 41 MGT B is sensitive to extreme weather conditions, such as excessive humidity in spring. Its resistance to drought is moderate. It does not adapt well to cohesive and compact soils.

The robustness transmitted by MGT 41 B in grafts is moderate to high. It generally shows a good affinity with varieties, although problems with Merlot or Pinot Noir varieties have been reported from time to time. The initial plant growth is quite slow. 41 MGT B helps to create solid grapes. It also tends to delay the germinal cycle of grafts compared to other rootstock, and products are usually contains less sugar and is slightly more acid.

The length and diameter of the internodes are medium and large-sized, and the wood production (15,000-50,000 m / ha) is low to moderate, and sometimes a certain percentage of wood is dry. In graft plants 41 B MGT is quite sensitive to both excessive soil moisture and intense water stress. Instances of sudden plant apoplexy and necrosis may also occur. 41 MGT B can be easily lignificated. The possibility of taking root is very small, and sometimes necrotic spots appear on the so-called "talon" of the rootstocks. However, grafting capacity is quite good. Particular care should be taken both during stratification in the special chambers and in how the rooting hormone is administered, in order to avoid large swellings at the grafting site.

41 B MGt is highly tolerant to the foliar form of phylloxera but is susceptible to downy mildew.