الفهرس 
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Abstract
The present study aimed to identify the common communities associated with Malva parviflora (common mallow), their distribution, diversity and environmental factors affected them. It aimed also at investigating the population dynamics, phytochemical, molecular and biological characteristics of the study species. Twelve habitats (fallow land, reclaimed land, desert roadside, salt marsh, railway, drain bank, agricultural roadside, orchards, canal bank, cultivated plants, cultivated crops, and desert land) were selected for collecting plant data, sampling and analysis of the study plant. The flora and vegetation of the associated species were studies and analyzed through a number of sample plots in the different habitats. In addition, quadrats (0.5 x 0.5 m) were selected for studying the population dynamics of common mallow and collecting plants for estimating some growth measurements (density, height, leaf area, biomass, etc.), nutrients and heavy metals analysis, molecular properties, possible allelopathic effect, and the phytochemical constituents (primary and secondary metabolites) and their biological activity against pathogenic microorganisms.
One hundred and forty-one species (88 annuals and 53 perennials) belong to 48 genera and 35 families were recorded associated with M. parviflora. The dominant families were Poaceae, followed by Asteraceae, Chenopodiaceae, Fabaceae, Brassicaceae, and Euphorbiaceae. Therophytes were the dominant life form, followed by geophytes-helophtes, chamaephytes, phanerophytes and hemicryptophytes. Pluri-regional elements were the dominant chorological elements, followed by mono-regional, bi-regional taxa and cosmopolitans. Thirteen species had a wide geographical distribution all over Egypt (i.e. occur in all the 12 geographical regions), 10 species were distributed in 11 regions, and one species was restricted to each of the Nile delta region, Red Sea, eastern Mediterranean coast and Marmarica region. According to the abundance categories of the recorded species associated with M. parviflora, it was found that 42.9% of the total species were common, while 31.6% were very common, 18.0% were rare and 7.5% were very rare.
A total of 101 species, representing 71.6% of the total species have either environmental services or economic goods. The environmental services of the recorded species could be arranged descendingly as follows: segetals, ruderals, sand controllers, poisonous plants, shaders and weed controllers. While, the economic goods were arranged descendingly as follows: medicinal, grazing, human food, fuel and timber. Moreover, fallow lands had the highest number of species (65 species), while reclaimed land had 23 species, desert roadsides: 45 species, salt marsh: 21 species, and railway and drain bank: 11 species. The statistical analysis (ANOVA1) detected significant variation in soil K and P, while non significant variation in N among the different habitats of M. parviflora. The soils of M. parviflora ranged from slightly alkaline (pH = 7.36) to alkaline (pH = 8.21). The soil of drain bank habitat had the highest values of Co2+, Cd2+, Zn2+ and Fe2+, while canal bank soil had the highest Ni2+ and the agricultural roadsides had the highest Pb2+.
The application of TWINSPAN on the cover estimates of 141 associated species recorded in the 151 sampled stands of Malva parviflora, led to the recognition of 14 vegetation groups: 4 vegetation groups are common in desert land habitat: A) Mesembryanthemum forsskaolii-Bassia indica, B) Bassia indica-Atriplex farinose, C) Plantago ovata-M. forsskaolii and D) A. halimus-Rumex dentatus; while D) A. halimus-Rumex dentatus was common in desert roadsides; G) Alhagi graecorum- Chenopodium murale in railways; J) Tamarix nilotica-Juncus rigidus in Salt marshes; and N) in fallow lands. Moreover, 6 vegetation groups are mixed and were represented in more than one habitat: F) Senecio glaucus subsp. coronopifolius-C. murale, H) C. Murale-Cynodon dactylon, I) C. murale-B. indica, K) Euphorbia peplus-E. helioscopia, L) Poa annua-Coronopus niloticus and M) C. dactylon-C. murale. VG (H) had the highest values of species turnover and Shannon index, while VG (B) had the highest species richness.
Cultivated mallow had the highest plant density followed by drain banks and fallow lands, while the reclaimed lands had the lowest. Common mallow plants from the desert roadsides had the longest root, while drain bank plants had the highest shoot, and agricultural roadside plants had the longest petiole. The highest value of leaf area was recorded for the plant leaves from the drain banks, while the lowest was recorded in cultivated mallow with the highest specific leaf area. The highest root and shoot production was recorded for cultivated mallow, while the highest root and shoot biomass were recorded for M. parviflora grown in canal banks. The highest chlorophyll a and total chlorophyll were recorded in agricultural roadsides, while the highest chlorophyll b was in cultivated plants, and the highest carotenoids were recorded in Malva leaves from the desert land habitat.
The highest contents of root N, P and K were recorded in cultivated mallow, agricultural roadsides and canal banks, respectively. On the other side, the highest shoot N, P and K were recorded in cultivated mallow, agricultural roadsides and cultivated crop. The highest concentration of Fe+2 was recorded in orchards plants, while the highest Cr3+ and Mn+2 were recorded in salt marshes, Cu+2 in the desert land, and Co+2 and Ni+2 in canal bank plants. On the other side, the highest concentrations of shoot Fe+2 was recorded in orchards, while Mn+2 was in railway, Cu+2 in desert land, Cr+3 in salt marshes, Co+2 in canal bank, and Pb+2 in orchards. The BF of heavy metals in M. parviflora fell in the order: Zn2+ > Mn2+ > Fe+2 > Ni2+ > Pb2+ > Cr3+ > Co2+ > Cd2+ , while the TF was in the order: Fe2+ > Mn2+ > Pb2+ > Co2+ > Cd2+ > Ni2+ > Cr3+ > Zn2+. The health risk index (HRI) for most investigated heavy metals, except Cd had values less than 1 for both adult and children.
The phytochemical screening of the ethanolic and chloroform extract of M. parviflora in the different habitats showed the presence of cardiac glycosides, flavonoids, amino acids, phenolic compounds, cellulose and hemicelluloses. The highest cardiac glycosides content was recorded in drain bank, while the highest flavonoids and phenolic contents were recorded in the drain bank and cultivated maallow, respectively. The separation and estimation of phenolic compounds in the leaves of M. parviflora identified ellagic acid, catechol, resorcinol, gallic acid and phloroglucinol, while the identified falvonoides were apigenin, luteolin, chrysoeriol, rutin, quercetin, kaempferol and avicularin. Eight free amino acids were recorded in the ethanol and chloroform extracts of M. parviflora: theronine, lysine, aspartic acid, serine, glutamin, leucine, norvaline and glutamic acid. The GC/MS analysis revealed the presence of two main active compounds: Physangulidine A and L-proline.
The germination of wheat grains was significantly affected, while that of clover seeds was not affected by applying Malva water extract. The results of allelopathy showed great variation in the root length and shoot height of wheat with the different concentrations of Malva water extract. The root length was greatly affected by Malva extract, while the shoot height was less affected. On the other hand, the root length of clover was markedly reduced with the increase of Malva extract concentration till 7.5%, and then increased again at 10.0%. In addition, 2.5% Malva extract enhanced the root length and shoot height of clover, while increasing the concentration reduced the root length and height.
The electrophoretic analysis of total protein extracts showed that the 12 accessions produced 11 bands; 4 of them (36.36%) are polymorphic and seven (63.63%) were monomorphic. Based on SDS-PAGE protein banding, Jaccard similarity coefficient among the 12 accessions of M. parviflora ranged from 0.73 to 1.00 with a mean of 0.87. The highest similarity (1.00) was recorded between accessinns of desert roadsides and salt marshes; railway and drain banks, agriculture roadsides, orchards and canal banks; and cultivated mallow and cultivated crop and desert lands. Generally the 6 primers produced 47 bands, 35 of them (73.6%) were polymorphic and 12 (26.4%) were monomorphic. Based on ISSR banding, the similarity coefficient between the 12 accessions of M. parviflora ranged from 0.53 to 0.84 with a mean of 0.66.
Sensitivity of pathogenic fungal and bacterial isolates to the M. parviflora extracts were investigated by measuring the microbial inhibitory growth. It was found that the most active extract against the test bacterial and fungal species was the ethanol extract, followed by chloroform, methanol and benzene, while diethyl ether extract had no effect on all tested organisms. The results of the microbiological activity of the benzene extract of M. parviflora reported moderate sensitivity on 3 microbial strains: B. subtilis, P. chrysogenum and A. niger. The ethanol extract (70%) from the agricultural roadside of M. parviflora had strong antimicrobial activity on the growth of the microbial isolates. The methanol extract of M. parviflora collected from the different habitats had no effect on B. subtilis and all tested fungi. Fractions potency was examined as antimicrobial agent. The results showed that fraction no. 7 and 8 of ethanol extract had activity against K. pneumonia and fraction no. 10 showed inhibition of growth of A. niger, while faction no. 20 had potency to inhibit growth of both K. pneumonia and A. niger.