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Growth stages and developmental patterns of guar
Author(s) -
Adams Curtis B.,
Boote Kenneth J.,
Shrestha Rajan,
MacMillan Jennifer,
Hinson Philip O.,
Trostle Calvin
Publication year - 2020
Publication title -
agronomy journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.752
H-Index - 131
eISSN - 1435-0645
pISSN - 0002-1962
DOI - 10.1002/agj2.20415
Subject(s) - guar , cyamopsis , biology , agronomy , crop , phenology , habit , psychology , psychotherapist
Guar [ Cyamopsis tetragonoloba (L.) Taub.], also known as clusterbean, is a crop plant grown in semi‐arid regions worldwide for the galactomannan gum of its seed, and as a forage, vegetable, and green manure. Despite the importance of guar and its products, uniform growth stage descriptions have not been established for the crop. Such descriptions allow for improved documentation and communication of the growth and phenological development of crops by researchers, producers, and others. Following models of other warm‐season, indeterminant‐growth legumes, such a system was developed for guar based on visually observable and sequential vegetative (V) and reproductive (R) plant events. The system was evaluated in two locations in dryland and irrigated conditions, using three morphologically contrasting guar varieties. The V stages begin with emergence (VE) and then are determined by counting the nodes on the main stem of the plant, with the cotyledonary node as zero [V0 to V(N)]. The R stages include R1 (First Flower), R2 (First Pod), R3 (First Seed or Full Pod), R4 (Full Seed), R5 (First Maturity), R6 (50% Maturity), and R7 (Harvest Maturity). The V and R stages may be reported alone or concurrently and applied at plant or crop scales. The stage descriptions apply to all growth morphologies of guar (i.e., branched and non‐branched) and accommodate the indeterminant growth habit of the plant. Season‐long data is reported from field studies on crop V and R stage progression, as well as data on crop growth, including biomass component partitioning, productivity, and canopy development.