Influences of temperature and water stress on germination and establishment of Prosopis caldenia Burk

Research was conducted to determine the effect of the temperature and the water stress on germination of Prosopis caldenia seeds, emergence and seedling survival, and early seedling growth. Water availability was most influential on germination of P. caldenia seeds when temperatures are either below (20 degreesC) or above (35 degreesC) optimum temperature. Radicle and hypocotyl lengths of P. caldenia seedlings were reduced by water stress in all temperature regimes. After 45 days, the effect of gradual dehydration of soil reduced emergence and seedling survival, and the growth (above- and underground) of surviving seedlings. The results suggest that P. caldenia seeds can apparently germinate and initiate early growth under conditions of water stress. However, water stress may reduce the probability of seedling establishment because of the effect of low soil water emergence, content on seedling survival, and growth of surviving seedlings. (C) 2001 Academic Press.