The Role of Covering and Antitranspirant substances on Control of Date Bunch Fading in Mazafati Cultivar

The phenomenon of date-bunch fading is one of the most important problems of some Iranian date producers. This disorder causes fruit shrinkage at the stage of Khalal to Routab conversion. Since the disorder is accompanied with the sudden increase of temperature and decrease of air relative humidity, in this research it was assumed that severe leaf or fruit transpiration is the cause of disorder, so the effect of chitosan and kaolin as anti-transpiration agents were investigated in combination with matting during 2012 and 2013 in Jiroft Agricultural Research Center on ‘Mazafati’ date fruits.
In the first year, fruits were sprayed with chitosan (0 and 1%) plus matting (with or without matting) at 3 replications and in the second year, the leaves were sprayed with kaolin (0, 2, 4 %) plus matting (with or without matting) at 4 replications using CRBD as factorial.
The results of the first experiment showed that chitosan could not reduce the severity of disorder, although it improved fruit weight and length and pulp to seed ratio to some extent. In the second experiment, leaf covering with kaolin caused dramatic reduction of disorder and had positive effects on fruit qualitative traits. The use of matting was effective in reducing disorder in both experiments.
The results of the experiment revealed that leaf transpiration plays a more important role in date-bunch dryness occurrence than fruit transpiration.