THINNING OF FRUITS AND ITS EFFECT ON DATE PRODUCTION IN DEGLET NOOR AND GHARSCULTIVARS. SUMMARY OF RESEARCH WORK IN THE OUARGLA REGION

Abstract

Thinning is one of the important cultural operations, which the date palm farmer must carry out to improve the quality of the production. Despite this, many farmers do not give it importance in terms of methods, times of achievement, or the cultivars whose operation must be practiced. To popularize the practice of this operation, we have carried out numerous studies on the methods of thinning, degrees and times of chiselling and the effect of the operation on some biometric characters, the water content of the dates, the yields and earliness in the two most important cultivars in Algeria: Ghars and Deglet Noor. Studies have shown the positive effect of thinning, with all these methods, compared to the control (without thinning). Combined chiselling gave better results compared to simple one, with both cultivars. For the time of chiselling, studies have shown that the chiselling of the ends is practiced with pollination or at the latest, one week after pollination. Heart chiselling is performed in the sixth week, or even the eighth week after pollination. The best degree of chiselling is 30% in both cultivars. Heart chiselling seems to be more recommended for the cultivar Ghars ; whereas the chiselling of the ends is more recommended for the Deglet Noor cultivar. Combined chiselling gave better results, with 20% chiselling of the heart and 10% chiselling of the ends for the Ghars cultivar and 20% chiselling of the ends and 10% chiselling of the heart in the Deglet Noor cultivar. Pollen with low germination is also used as a means of thinning fruit. It improves the quality of the fruits of the two cultivar