A field experiment was carried out during 2017, 2018 and 2019 seasons on ten year old "Dolce" olive trees grown at private orchard, at Siwa oasis, Marsa Matrouh governorate, Egypt. The aim of this study is evaluating the effect of methionine, ethephon and thiourea as assistant treatments to hand vibration harvest and their effects on leaf (drop and total chlorophyll content) and fruit quality as well as their effect on the next flowering of "Dolce" olive trees. Trees were sprayed, two weeks prior to harvest date with one of the following solutions: (1) control (tap water), (2) methionine at 1000 or 2000 ppm, (3) ethephon at 2000 or 3000 ppm, (4) thiourea at 1000 or 2000 ppm. Control trees recorded the highest fruit detachment force, the highest percentage of hand-picked fruits and the least shed leaves per tree. Ethephon, thiourea and methionine treatments reduced fruit detachment force and supported hand vibration harvest, but increased leaf drop over control trees. All tested treatments gave the highest positive effect on fruit anthocyanin and carotene content as compared with the control. Moreover, perfect flowers and fruit set percentages in the following year responded positively to all treatments, meanwhile, ethephon treatment at 3000 ppm proved to be the most efficient treatments in this concern. Methionine succeeded in enhancing harvesting efficiency percentage and improved fruit color, while it resulted in the lowest effect on fruit removal force, hand-picked fruits percentage and total leaf drop compared to ethephon and thiourea.

The trial was conducted through 2017, 2018 and 2019 seasons on 9 years old "Kalamata" olives cultivated at 5×5 m apart in sandy soil. Trees were irrigated from a well using a drip irrigation system. To investigate the effects of calcium chloride and ascorbic acid as foliar spray Firstly: on yield and fruit quality, Secondly: on the next flowering, fruit set of "Kalamata" olive trees.Sprayed "Kalamata" olive trees with calcium chloride at (1.0 and 1.5%), ascorbic acid at (1500 and 2000 ppm) and calcium chloride at 1.5% combined with ascorbic acid at 2000 ppm were carried out at three times, in mid-May (end of fruit set), in mid-June (during pit hardening) and in performed second week of October.The results revealed that calcium chloride and ascorbic acid foliar spray induced a positive effect on leaf chlorophyll and calcium content, yield, biennial bearing index, fruit quality i.e. pulp thickness and pulp oil content as compared with control treatment of "Kalamata" olive. They also improved the next flowering; number of panicle/shoot, number of total flowers/ panicle, fruit set compared to untreated trees.Briefly, foliar spray "Kalamata" olive trees with calcium chloride at 1.5% plus ascorbic acid at 2000 ppm at three times during fruit development was able to improve yield and fruit quality also, it enhanced the next flowering and fruit set.

field experiment was conducted during 2018 and 2019 seasons on El-shamia cactus pear plants orchard about eight years old, grown in sandy soil under drip irrigation system from a well located in Abu Ghaleb area, "Cairo-Alexandria desert road" about 50 km from Cairo, Egypt. The aim of study was the evaluation of the effect of cattle manure soil application rates; i.e. 20, 30 and 40 kg/plant and humic acid at 3 rates; i.e. 0, 10 and 20 g/plant as well as their interactions on growth, cladodes nutrients content, yield and fruit quality and investment ratio of cactus pear plants. Resulted showed that increasing cattle manure rates induced a progressive enhancement of the growth, cladodes nutrients content, yield and fruit quality. Moreover, humic acid at 20 g/plant surpassed the other two tested rates in enhancing the previously mentioned studied traits. Furthermore, cattle manure and humic acid as well as their combinations had positive effects on net profit and investment ratio. Finally, it is preferable to apply cattle manure at 40 kg/plant combined with humic acid at 20 g/plant to enhance growth, yield and fruit quality as well as cladodes nutrients content of El-shamia cactus pear. Besides, cattle manure at 30 kg/plant combined with humic acid at 20 g/plant attained the highest value of total revenue per feddan, net profit per feddan and investment ratio. The effects of cattle manure and humic acid as well as their combinations were cumulative and the second season was better than the first season in productivity and net profit as well as investment ratio.

This trial was carried out on olive trees grown in the private orchard, Siwa oasis, Matrouh governorate, Egypt, during 2017, 2018 seasons. Trees were planted at 5x5 meters apart in sandy soil and irrigated by a flood system from agricultural drainage canal. This study aimed at studying the effect of olive-wheat in intercropping system and the application of humic acid on tree growth, yield and fruit quality of "Manzanillo" olive. The experiment was designed as a randomized complete block design with five replicates for each treatment and each replicate was represented by one tree. The results showed that vegetative growth i.e. tree dimensions, shoot growth, leaf characteristics, blooming and yield recorded the highest values in intercropping olive fertilized (30g) humic acid with wheat crop fertilized (4kg) humic acid/fed treatment. Furthermore intercropped olive with wheat produced less vegetative growth, blooming and yields of Manzanillo olive trees as compared with monoculture. Moreover, high level treatment of humic acid increased vegetative growth, blooming and yield of Manzanillo olive trees as compared with non-humic acid treatment in both seasons. The intercropping Manzanillo of olive trees treated with humic acid with wheat plants fertilized with humic acid system could be valuable for sustainable farming a source of income to the farmers in this region.