Emergence, Growth, and Reproduction of Horse Purslane (Trianthema portulacastrum) as Influenced by Environmental Conditions

The effect of environmental conditions on horse purslane (Trianthema portulacastrum L. # TRTPO) emergence, growth, and reproduction was studied by sowing seeds on June 10, June 30, July 20, August 10, and August 30, 1984. The first three seeding dates resulted in significantly higher seedling emergence than the August 30 date. Leaf number, leaf area, dry matter, and number of branches per plant at the peak growth stages of this weed were significantly higher for the July 20 sowing than for the other sowing dates, followed closely by the June 30 sowing. Similarly, number of nodes per plant, seeds per plant, and seed weight per plant were also significantly higher for the July 20 sowing, followed closely by the June 30 sowing. Phenological behavior of the plants indicate that: a) maximum seedling emergence takes place during June and July, b) rapid and vigorous growth occurs during July and August (rainy season) when conditions for growth are optimum, and c) production of flowers and seeds starts 20 to 30 days after sowing.