Effect of foliar application of some nutrients on maize ears rot disease, synthase of anti-defense compounds, quality of maize grains and bread

الملخص EN

This study was performed to investigate the effect of foliar spray by each of urea, boron, zinc, potassium alone and/or mixed of each with urea on maize ears and grains rot disease development, observe the chemical composition, phenolic compounds, antioxidant activity (DPPH), trypsin and α- amylase inhibitors activity of different treatments of maize grains.

As well as, evaluate the sensory properties of balady bread prepared using different levels of corn flour and Gum Arabic as substitution of wheat flour.

Moreover, the quality characteristic of dough.

In vitro treatment of urea alone and/or its mixture with each of boron, zinc and potasium significantly reduced radial growth and sporulation of Fusarium moniliforme fungus on PDA medium followed by each of boron and zinc alone.

While potassium was not effective in this respect compared to control.

The effect of foliar nutrients applied on maize ears and grains rot disease was quantified and possible modes of action during field conditions.

Twice applications at 50 and 65 days from planting by mixture of urea and boron; urea and zinc; urea and potassium were more effective than the treatment with each of urea, boron, zinc and potassium alone, provided the least disease and consistently better of yield and 100 grain weight.

The effect of nutrients were really extended to reduce associated maize grains fungi infection, especially the main causal pathogen for ears and grains rot caused by F.

moniliforme compared to control.

Significantly difference between nutrients and application dates were found.

Quality of maize grains treated with different nutrients were investigated.

Results showed that, twice application of boron alone and mixture of urea and zinc produced maize grains contained the highest contents of crud protein (10.60 and 10.40%, respectively) while the lowest value of crud protein was 9.35% for treatment with urea and boron mixture applied twice.

On the other hand, maize grains treatment with mixture of urea and zinc applied twice contain the highest content of total polyphenols extracted which was (320 mg GAE/100g) followed by mixture of urea and boron applied twice which recorded (305 mg GAE/100g), while the lowest value of total polyphenols extracted was (215 mg GAE /100g) for control maize grains.

Furthermore, maize grains treated with mixture of urea and zinc applied twice contain the highest content of antioxidant activity (DPPH) (89.10%); trypsin inhibitor activity (T1A), (0.51 IU/mg) and α-amylase inhibitors (12.75 AIU/g) compared with control maize grains.

Furthermore, the farinograph results indicated that, arrival time (min), developing time (min), dough stability (min) and weakening value (B.U) increased, while water absorption (%) decreased with increasing the level of adding corn flours and Gum Arabic when compared with wheat flour control.