Study of the effect of using rock phosphate with organic and sulphur fertilizers on fennel grown in sandy soil

Proper management of fertilizer consumption requires an understanding of the interaction between rock phosphate and other fertilizers. This can be achieved thru improving the effectiveness of various rock phosphate fertilizers while considering the cost and economic return of adding them to crops. The current study aimed to improve the yield, quality, and chemical properties of fennel oil by using rock phosphate, organic, and sulfur fertilizers. during the 2020 and 2021 seasons at the Faculty of Agriculture's farm at Ain Shams University in Shubra El-Khaimah, El-Qalyubia, Egypt. The randomized complete block design was carried out with three replications. The results show that adding rock phosphate fertilizer and other fertilizers improved the morphological and chemical characteristics of fennel plants compared to the control treatment in both seasons. The highest seed and straw yields were obtained from fennel enriched with rock phosphate rate (360 kg/ha+240 kg/ha sulphur). The best results for pectin, anethole, and essential oil were also obtained from the seeds. These results were followed by the rock phosphate rate (360 kg/ha+12 t/ha compost). The lowest recorded parameters were super phosphate at 360 kg/ha compared to the control treatment. From this study, it can be concluded that to achieve the highest yield and quality of fennel crops, rock phosphate should be added with sulfur at a rate of 720 kg/ha+480 kg/ha sulphur.