بررسی اثرات نوع و زمان پوشش خوشه های خرما در جلوگیری یا کاهش احتمالی خسارت عارضه خشکیدگی خوشه خرما

Date bunch fading disorder has been the most important problem of date growers in Kermao , Hormozgan, Bushehr, Fars and Sistan & Belucbistan provinces in recent years. This usually take place during fruits are Changing from Khalal to Rotab stage. Weather fluctuation have significant effects on incidence and severity of disorder, also consideration of cultural practices have positive effects on decreasing of its damage. In this study, the effects of two factors including. time and kind of bunch covering were studied as factorial experiment in form of Randomized Complete design with 8 replication on cvs Mozafti in Jirofot , Mordaseng in Roodan and Kabkab in Bushebr during 2001-2002. The time of bunch covering were Kimri and Kba1al stage and the kind of covers were mat basket, plastic bag, hemp bag. cloth net bag and without cover (control) . Sampling for determining of damage rate of disorder within the treatments was done at the time of harvesting. The experimental data of the two years were combined anafyzcd and the means of the treatment were compared using Duncan test. The result of the tIuee areas were as fallow: The effect of cover factor on reducing disorder damage on cvs. Mordaseng in Roodan, Mozafti in Jiroft and Kabkab in Boushebr showed significant diffClCDce. The effect of covering time in Roodan and jiroft showed no significant dift"erence but in Bousber it showed significant difference. The means of damage pertent OD cv Mordaseng in plastic bag (class A), mat bag (class AB), cloth'nct bag (AB), hemp bag (class BC) and control (class C), were 23.8, 31.17, 34.57. 49.31 and 54.8 respectively. The mean of damage percent on cvs Mozafti in mat basket (class A), hemp bag (class B),; cloth net bag (class BC) , plastic bag (class CD) and control (class D) were 16.5, 23.5, 27.35, and 66 percent Respectively. The mean of damage percent on cvs Kabkab in mat bag (class A) hemp bag (class A), plastic .' bag (class A) , cloth net bag (class B) and control (class C) were 3.62,3.96 , 4 , 5.16 and 17.81 . respectively. Covering bunch at middle ofKimiri (class A) andKhalal (class B) stage showed 6.69 and 7.14 damage peItCIlt respectively. In conclusion, the mat basket is recommended as the best tIealment for covering of date bunches at Khala1 or Kimiri stage due to its desirable effect on decreasing the disorder damage. Cheapness, abundance, availability and long longevity