Growth and Performance of Guar Genotypes Under Various Planting Dates in Desert Southwest.

Guar (Cyamopsis tetragonoloba L.) is a drought tolerant, summer annual legume that can be a potential drought tolerant alternative crop in the semi-arid regions of desert southwestern US. Growth and yield performance of various guar genotypes was evaluated from 2014-2015 under different planting dates in southern and eastern parts of New Mexico (NM). At Las Cruces in southern NM, eight genotypes were tested under four different planting dates (April 25, May 15, June 16 and July 1) while four genotypes were tested under three planting dates (June 18, July 7 and July 22) at Clovis in eastern NM. The mid-June planting of guar lines resulted in better stand establishment, higher plant height, higher seed yield and yield attributing characteristics including clusters per plant, pods per cluster, pods per plant, seeds per plant, seeds per pod, 1000-seed weight as compared to other plantings at Las Cruces in southern NM. Performance of guar genotypes varied with planting time. In late-April and mid-May plantings, NMSU-15-G1 produced maximum seed yield, while in the mid-June and early-July plantings, Matador and Lewis had highest seed yield, respectively. Comparing planting dates within genotypes, NMSU-15-G1 consistently had higher seed yield in first three plantings than in early-July planting; while Matador had higher seed yield in the mid-June planting compared to the other plantings. Lewis had consistent, but lower seed yield comparatively. When compared at Clovis in NM, the mid-June planting of guar consistently had taller plants, better stand establishment and higher above ground dry biomass than July plantings. Higher seed yield and yield attributing characteristics of guar were also observed under June planting than under July plantings. The genotypes did not show any significant variation in their performance at Clovis. Results indicated that mid-June was the most optimum time for planting guar in southern and eastern New Mexico.