Taher Yehia

A field trial was conducted to determine the effect of nitrogen fertilizer rates and dates of added on the yield, fruit quality and oil of “Manzanillo” olive trees in a private orchard at Cairo-Alexandria desert road (about 50 Km from Cairo), Egypt. The application of ammonium sulphate at the rate of 1 kg /tree in each of February, May, June and August increased significantly yield, fruit quality (weight, size, diameter and pulp/seed ratio) and oil content in fruit.

2 Abstract: Flower bud explants from Le Conte pear were cultured individually on MS medium supplemented with 0.1 mg/L 6-benzylaminopurine (BAP), 30 g/L sucrose and 7.0 g/L Difico Bacto agar. Different root pruning treatments (0.0, 30, 60 and 90 cm) from the trunk of mother plants during bud break and full bloom stages and Medium strength (Full, one- half and one-fourth) were tested. Data indicated that bud break stage surpassed full bloom stage in all parameters under study (shoot length, number of node, number of branch, explants development, fresh weight, number of leaves and greening). Moreover, using root pruning treatments (30 cm) was better than (0.0, 60 and 90 cm). Also, one- half treatment enhanced the proliferation percentage and shoot number compared with the other treatments.

Abstract: Suckers of jujube grown at Maryout Experiment Station, Desert Research Center (north western coast of Egypt) were studied under irrigation at different levels of available soil moisture (100%, 75%, 50% and 25%) during two successive seasons 2008 and 2009 ...

2 Abstract: The present study aimed to evaluate the effect of root pruning on vegetative growth and leaf mineral content of "Le Conte" pear trees grown in Agricultural and Experiments Researches Station of the Faculty of Agriculture, Cairo University at Giza Governorate, Egypt. This study was conducted on 11-year old "Le Conte'' pear trees grown in loamy soil at 5X5 m during three successive seasons. Root pruning treatments involved 30, 60 and 90 cm at a depth of 50 cm from both sides of trunk at bud break and full blood stage during seasons 2008, 2009 and 2010. Results indicated that the direct and residual effect of all treatments significantly decreased shoot length, diameter and leaves number per shoots. However, the direct and residual effect of the 30 cm root pruning treatments produced the highest significant leaf area. Meanwhile, the residual effects of all treatments produced the highest significant of leaf N, P, K in all seasons. On the other hand, l...

The present investigation was carried out at the experimental orchard of Kassaseen Research Station (Ismailia Governorate) , to study the effect of some treatments on improving pomegranate fruit quality of pomegranate trees Manfalouty cvduring 2003 and 2004 seasonsThe applied treatments were hand thinning (after two or four weeks of full bloom) , girdling of the main branches (3 mm or 5 mm in diameter) after two weeks of full bloom , spraying paclobutrazol at 250 and 500 ppm , gibberellic acid at 30 and 60 ppm , glutathione at 15 and 25 ppm , calcium chloride at 2 and 3 , boric acid at 02 and 03 , zinc sulphate at 02 and 03 , copper sulphate at 02 and 03 and manganese sulphate at 02 and 03All treatments were added as spraying twice / year (two and eight weeks after full bloom) The obtained results showed that all treatments improved pomegranate fruit quality in terms of significant reduction of fruit cracking percentageMeanwhile the applied treatments significantly increased of frui...

This study was conducted during two successive seasons 2009 and 2010 on ten years old “Manzanillo” olive trees, planted at 5 × 5 m grown in sandy soil in a private orchard at Cairo-Alexandria desert road (about 50 km from Cairo), Egypt. The investigation aimed to study the effect of dates of ammonium sulphate 20.6%N applications as nitrogen fertilization source and minimize the rate of added annually amounts by 20% on vegetative growth and photosynthetic pigments of “Manzanillo” olive trees. The obtained results indicated that the application with ammonium sulphate at 1 kg/tree in each of February, May, June and August increased significantly vegetative growth; leaf area, leaf dry weight and specific leaf weight and photosynthetic pigments.