Susceptibility of certain rice varieties to infestation, with the rice stem borer, Chilo agammemnon Bles [electronic resource].

Includes reference.

This study was conducted at the experimental farm of Rice Research & Training Center. Economic Entomology Dept., and Soil Science Dept .• Kafr EI-Sheikh Fac. of Agric .• Tanta University during two successive seasons; 2003 and 2004. Susceptibility to infestation with the rice stem borer Chilo agamemnon Bles. of the three hybrid rice genotypes and Salcha 101 rice variety indicated that Sakha 101 was the least susceptible (1.000.10 damage). On the other hand, the most susceptible rice hybrid was SK 2025H 11.1 S% damage. it received more eggs than Sakha 101 cultivator. Fertilized rice plants with high levels (80 unit) of nitrogen had higher infestation than that manured with the lower (40 or 60 wits) levels. However. to minimize insecticide applications in rice fields and meanwhile to obtain satisfactory rice yield, it is recommended to use 6 kg carbofuran I fed. The relationship between morphological characters and infestation was studied.. Significant positive correlations were found between rice stem borer infestation and each offlag leaflength, flag leaf width and plant height. By contrast, significant negative correlations were found between the infestation and heavy tillering. In the present work, the relationships between some chemical components and damage caused by Chilo agamemnon were studies. The high values of infestation were detected in rice varieties having low silica contents and By contrast, varieties suffering low infestation had the highest silica content. Zinc content of rice stem had also negative effects on rice stem borer damage. In the current study. iron negatively correlated with percentage of infested stems. By contrast. potassium, pH, phosphorus. manganese positively correlated with the infested stems.

Summary in Arabic.

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