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Banana production is severely hindered by plant-parasitic nematodes (PPNs) worldwide. Chemical nematicide, oxamyl is a systematic compound widely applied for the control of PPNs. Because of increase pests' problems, harmful effects on human and environment caused by chemical pesticides and also increased consumer requirements for safe crops have encouraged research on bio-pesticides production. So, the effect of different stress of the yeast, Saccharomyces cerevisiae and blue green algae (cyanobacteria), Spirulina platensis were examined on banana plants infected with root-knot nematodes, Meloidogyne incognita. All tested treatments were effective methods to manage M. incognita in soil samples and banana roots. Notably, the usage of S. cerevisiae and S. platensis in combination treatment revealed the greater antagonistic action on M. incognita in potted banana. In addition it has an avail advantage over artificial nematicides by having several means to attack the RKN and mainly enhanced plant growth compared to any other treatments. Yet, the previous treatment had increased catalase (CAT) enzyme activity and reduced pectin methyl esterase (PME) activity in banana plant that leads to inhibit the count of the RKN. Generally, our results supply a novel knowledge to understand of PPNs management as a new approach for applying bio-fertilizer and bio-control of the parasitic nematodes.

Cyanobacteria are one of the richest sources of biomedical relevant compounds with extensive therapeutic pharmaceutical applications and are also known as producer of intracellular and extracellular metabolites with diverse biological activities. The genus Anabaena sp. is known to produce antimicrobial compounds, like phycocyanin and others. The goal of this study was to optimize the production of these bioactive compounds. The Plackett-Burman experimental design was used to screen and evaluate the important medium components that influence the production of bioactive compounds. In this present study, eight independent factors including NaNO 3 , K 2 HPO 4 , MgSO 4 Á7H 2 O, CaCl 2 , citric acid, ammonium ferric citrate, ethylene diamine tetraacetic acid disodium magnesium salt (EDTA-Na 2 Mg) and Na 2 CO 3 were surveyed and the effective variables for algal components production of Anabaena oryzae were determined using two-levels Plackett-Burman design. Results analysis showed that the best medium components were NaNO 3 (2.25 g l À1 ); K 2 HPO 4 (0.02 g l À1 ); MgSO 4 (0.0375 g l À1 ); CaCl 2 (0.018 g l À1 ); citric acid (0.009 g l À1 ); ammonium ferric citrate (0.009 g l À1 ) and EDTA-Na 2 (0.0015 g l À1 ) respectively. The total chlorophyll-a, carotenoids, phenol, tannic acid and flavonoid contents in crude extract of Anabaena oryzae were determined. They were 47.7, 4.11, 0.256, 1.046 and 1.83 lg/ml, respectively. The antioxidant capacity was 62.81%.

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