الفهرس 
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Abstract
Trianthema portulacastrum L. (Aizoaceae) was originally known from Egypt as a very rare plant recorded in the Gebel Elba. Recently, it had been reported to be widely distributed, in crop fields of Egypt. The present study aims to determine the
distribution of this species in Nile Delta, to assess the factors that affect its invasion to
the study area, and determine the associated species and plant communities. It aims
also at assessing its germination capacity and morphological plasticity through
studying several morphological traits. One hundred and thirty stands were sampled
during summer 2009 – 2010 to represent the variation in the natural population of
Trianthema portulacastrum in Nile Delta. These stands represent the distribution of
Trianthema in four Governorates (10 stands in Kafr El-Shiekh, 8 in Minufya, 23 in
Gharbia and 89 in Qaliubiya) and five fields (corn, cabbage, sweet potato, banana and
orange), in addition to the waste land and irrigation canals.
Soil of orchards (orange and banana) have the lowest clay (35.1g), sand
(39.1g) and silt (25.7) ; but have the highest nitrogen (0.2 mg100g-1). Summer crops
have the highest EC (4.4 mSCm-1), nitrogen (0.2 mg100g-1), CaCO3 (7.8 mg100g-1),
and the lowest organic matter (0.69), and the highest phosphorous (6.9 mg100g-1).
Waste lands have the highest organic matter (0.9 mg100g-1) and potassium (40.3
mg100g-1); and the lowest pH (7.6). Irrigation canals have the highest pH (8.1), clay
(58.6 g), and silt (28.3 g) and the lowest organic matter (0.69mg100g-1), nitrogen
(0.22mg100g-1), CaCO3 (7.83mg100g-1), potassium (23.33 mg100g-1), phosphorous
(6.3 mg100g-1) and sand (12.94 g).
The total number of plant species recorded associated with Trianthema
portulacastrum in Nile Delta was 67 species which belongs to 22 families and 56
genera. Twelve species were distributed in four habitats: Trianthema portulacastrum,
Portulaca oleracea, Amaranthus caudatus, Amaranthus hybridus subsp. hybridus,
Oxalis corniculata, Hibiscus trionum, Xanthium spinosum, Bracharia eruciformis,
Setaria pumila, Echinochla colona, Digitaria sanguinalis, and Cyperus rotundus var.
rotundus. In addition, 10 species were found in three habitats: Amaranthus viridis,
Amaranthus spinosus, Amaranthus lividus, Euphorbia heterophylla, Euphorbia
prostrata, Corchorus olitorius, Malva parviflora, Plantago major, Conyza
bonariensis, and Bidens pilosa. Eight species were restricted to 2 habitats Rumex
dentatus, Chenopodium album, Euphorbia retusa, Euphorbia peplus, Ricinus