Variety traits
Cold tolerance is a biological characteristic of a variety that determines its ability to develop and maintain productivity under prolonged exposure to low positive temperatures (from +1 to +10 °C).
Mentioned in descriptions 2 844 varieties reference book.
Cold tolerance represents the ability of an organism to maintain normal metabolism, protoplasm structure, and enzymatic activity under conditions where thermophilic crops begin to slow growth, yellow, and lose turgor. Unlike winter hardiness, this indicator does not imply the tolerance of sub-zero temperatures and freezing of tissues. In practice, a cold-tolerant variety allows for early sowing in unheated soil, reduces the risk of seedling death during spring cold snaps, contributes to the efficient use of winter moisture, and accelerates development, which often leads to earlier maturity.
Field and laboratory evaluation methods are used during variety testing. The field methodology includes phenological observations of growth rates during early sowing, visual assessment of survival after temperature stress, and structural analysis of the impact of conditions on yield components. In laboratory settings, a 'cold test' is used for seed germination in incubators at reduced temperatures followed by further growth, as well as biochemical analysis, such as determining the level of free proline in leaves.
Cold tolerance is expressed through a coefficient calculated as the ratio of performance in stress conditions to control conditions, or through percentage values of germination. Based on these data, varieties are divided into groups by resistance level. An important indicator is the temperature minimum at which crop growth ceases, which is about +4 °C for most plants and up to +10 °C for maize. Variety selection requires consideration of the biological characteristics of the crop, as this trait is critical for thermophilic plants at the early development stage.
Selection based on the description text, not official resistance ratings: such data is not available in registers. Mention indicates that the trait is discussed in the variety's sources; see the variety's profile for details on what is specifically stated.
Brassica oleracea L. (Savoy Cabbage Group) · Savoy cabbage
Willem van Haerke
Zea mays L. · Maize
Syngenta Participations,CH
Allium porrum L. · Leek
Hazera Seeds B.V.
Zea mays L. · Maize
Revol Benoit
Brassica napus var. napus · Rapeseed
KWS SAAT SE & CO.KGAA
Festuca rubra L. · Red fescue
W.W. Johnson & Son Ltd.
Glycine max (L.) Merr. · Soybean
LIMAGRAIN GENETICS
Daucus carota L. · Carrot
MORAVOSEED
Avena sativa L. · Oat
Mattsson Bengt
Lactuca sativa L. · Lettuce
Vilmorin, F
Brassica oleracea L. (Curly kale Group) · Curly kale
BEJO ZADEN
Spinacia oleracea L. · Spinach
Henk Driessen
Triticum aestivum L. · Bread wheat
Michael Winzeler
Rosa L. · Rose
Meilland International
Zea mays L. · Maize
Roland Debeuf
Zea mays L. · Maize
Dr. Frank K. Rober
Zea mays L. · Maize
Pierre CAROLO
Glycine max (L.) Merr. · Soybean
Thom Hoffman
Helianthus annuus L. · Sunflower
Remy ROUANET
Helianthus annuus L. · Sunflower
Remy ROUANET
Zea mays L. · Maize
TAUCHER ROBERT
Helianthus annuus L. · Sunflower
Zea mays L. · Maize
KWS| KWS SAAT AG
Brassica napus var. napus · Rapeseed
Werner Horn