In biology, the BBCH-scale for cotton describes the

phenological Phenology is the study of periodic events in biological life cycles and how these are influenced by seasonal and interannual variations in climate, as well as habitat factors (such as elevation). Examples include the date of emergence of leaves ...

development of

cotton plant ''Gossypium'' () is a genus of flowering plants in the tribe Gossypieae of the mallow family, Malvaceae, from which cotton is harvested. It is native to tropical and subtropical regions of the Old and New Worlds. There are about 50 ''Gossypiu ...

s ''Gossypium hirsutum'' using the

BBCH-scale The BBCH-scale is used to identify the phenological development stages of plants. BBCH-scales have been developed for a range of crop species where similar growth stages of each plant are given the same code. Phenological development stages of plan ...

. The phenological growth stages and BBCH-identification keys of cotton are: 1 Leaves are counted from the cotyledon node (= node 0)
2 Side shoot development may occur earlier, if there is a vegetative side shoot continue with principal growth stage 2. If there is a reproductive side shoot (fruiting branch) continue with the principal growth stage 5
3 Vegetative side shoots are counted from the cotyledon node
4 "pin-head square" or "match-head square" is the first square which forms at the first fruiting position of the first fruiting branch

References

* {{cite journal , last = Munger , first = L. , author2=H. Bleiholder , author3=H. Hack , author4=M. Hess , author5=R. Stauss , author6=T. van den Boom , author7=E. Weber , title = Phenological Growth Stages of the Peanut plant (Arachis hypogaea L.) Codification and Description according to the BBCH Scale – with figures , journal = Journal of Agronomy and Crop Science , volume = 180 , pages = 101–107 , date = 1998 , doi = 10.1111/j.1439-037X.1998.tb00377.x , issue = 2 BBCH-scale