SOME INTERNAL CHANGES IN DATE PALM TREES AS A RESULT OF INFESTATION WITH RED PALM WEEVIL, Rhynchophorus ferrugineus OLIVE. (CURCULIONDAE: COLEOPTERA)

Abstract

Internal changes of temperature, moisture content and PH values of infested date palm trees with red palm weevil, Rhynchophorus ferrugineus were studied. The results indicated that internal Palm tree temperature at 6 am, Palm tree temperature at 12 pm and mean temperatures were increased in infested areas in infested trees during the different months. . Palm tree temperature at 6 am inside infested trees ranged between 12.8º C ( in January) and 34.8º C ( in August). The differences of Palm tree temperature at 6 am. between infested and healthy trees ranged between 0.1º C in January and 6.1º C in April. Palm tree temperature at 12pm in infested trees ranged from 11.9 ºC in January to 30 ºC in December and 7.8 ºC in October. Mean temp. in infested trees ranged between 12.4ºC in January and 32.4º C in August, while, the differences ranged between 2.2º C in January and 6.9 ºC in October.The moisture contents decreased in infested trees (ranged between 59.5 % in March and 78.3 % in November, while the differences ranged between 0.2 % in May and 9.6 % in March.PH values were lower inside infested areas than in healthy trees, where the range in infested trees fluctuated between 4.23 in May and 5.28 in March. The differences in PH ranged between 0.45 in March and 1.60 in June.