IMPACT OF FOLIAR-APPLIED DORMANCY-BREAKING AGENTS ON FLOWERING BEHAVIOR, YIELD, FRUIT QUALITY, AND SOME CHEMICAL CONSTITUENTS OF “EIN SHAMER” APPLE TREES

Objective: This investigation was carried out during the two successive seasons of 2016 and 2017 to investigate the effect of Dormex, mineral oil, potassium nitrate, calcium nitrate, and thiourea on bud break, growth, yield, and some chemical constituents of “Ein Shamer” apple (Malus sylvestris, Mill) variety. Methods: The trees were grown in loamy sand soil, and sprayed with six treatments (Dormex (4%), mineral oil (5%), potassium nitrate (8%), calcium nitrate (8%), and thiourea (2%) and control. Results: In general, it was found that all studied growth parameters, date of flower bud break, percentage of bud break, fruit-setting, fruit weight, fruit size, fruit number/tree, yield/tree (kg), and some chemical constituents of leaves (total chlorophyll, total carbohydrates, total protein, nitrogen, phosphorous, and potassium contents) and some chemical constituents of fruits total soluble solids (T.S.S.), T.S.S./acid ratio, Vitamin C, water content %, total free amino acids, total carbohydrates, total sugars, and reducing sugars) were increased with the application of the different treatments. Conclusion: The best results were obtained from the treatment of Dormex at 4% and mineral oil (5%). On the contrary, the same treatment decreased total acidity and total phenols in fruits as compared to the control. It could be recommended to use Dormex at 4% and mineral oil (5%) for improving bud break, growth, yield, and chemical constituents of apple trees or fruits

THE CONTROL OF APRICOT SEED DORMANCY AND GERMINATION BY LOW TEMPERATURE TREATMENTS

Objective: Freshly harvested seeds of “Local” apricot variety were found to be dormant and did not germinate at all. A specific low-temperature stratification treatment was required to overcome seed dormancy. The most effective temperature for breaking seed dormancy, germination, and seedling growth was 5°C cold stratification (CS). Increased seed germination percentage was recorded when the period of stratification prolonged. Seedling developed from stratified seeds had better growth than those developed from non-stratified seeds. Methods: For stratification treatments, the seeds with removed endocarp were mixed with moistened sand. Afterward, they were subjected to a period of stratification at 5°C. Seeds were stratified in pots of 30 cm×40 cm. Stratified seeds were regularly irrigated once per week. To prevent the water loss during stratification upper surface of pots was covered by a sack. The following stratification was applied for apricot variety: CS for 0, 3, 6, 9, 12, and15 days in 1998 and 1999 years for “Local” variety. Results: Apricot seeds required a CS of about 15 days for “Local” variety to reach maximum germination and normal seedling growth. Moreover, when stratification period was prolonged, some of the chemical constituents of apricot seeds were increased and other was decreased. Therefore, it can be suggested that breaking of dormancy is coincided with several changes in different chemical constituents of seeds. Some of these materials increased (total, reducing and non-reducing sugars, total free amino acids, total indoles, and total and conjugated phenols) and other materials such as free phenols which decreased at seed germinations. Conclusion: The most effective temperature for breaking seed dormancy, germination, and seedling growth was 5°C CS. Increased seed germination percentage was recorded when the period of stratification prolonged. Seedling developed from stratified seeds had better growth than those developed from non-stratified seeds

PHYSIOLOGICAL AND BIOCHEMICAL RESPONSES OF WHEAT (TRITICUM AESTIVUM L.) PLANTS TO POLYAMINES UNDER LEAD STRESS

Objective: The distribution, growth, development and productivity of wheat plants are greatly affected by various abiotic stresses such as lead (Pb) stress which become one of the most abundant toxic metal in the earth crust. Under the three applied polyamine (PAs) applications, the efficiency of wheat plants to tolerate Pb2+ stress in terms of growth and yield characteristics was noticed to varying degrees. Methods: The current study focused on the impact of 2.0 mM lead (Pb2+) on growth and performance of wheat plants before and after PAs applications. The sterilized seeds were soaked for 8 h at room temperature, either in distilled water (as a control), 0.25 mM spermine (Spm), 0.50 mM spermidine (Spd), or in 1.0 mM putrescine (Put). Results: Point out that, better growth and yield characteristics, chlorophyll “a” (Chl-a), chlorophyll “b” (Chl-b), soluble sugars, indoles, and enzymatic antioxidants (i.e., peroxidase (POX), catalase, ascorbate peroxidase, ascorbate oxidase, polyphenol oxidase, and glutathione reductase) and the enzyme α-amylase contents were obtained with seed soaking in 0.25 mM Spm, 0.50 mM Spd, or 1.0 mM Put than those generated with seed soaking in water under 2.0 mM Pb2+ stress. In contrast, the concentration of endogenous Pb2+ was significantly reduced. Conclusion: Among all tested PAs, 1.0 mM Put showed the best results and thus is recommended, as seed soaking, for wheat to grow well under Pb2+ stress

Metabolic Changes in Chemical Constituents, Flowering Behavior, Yield And Fruit Quality of ‘Anna’ Apple (Malus sylvestris, Mill) Trees with Foliar Application Some Compounds

This investigation was carried out during the two successive seasons of 2006 and 2007 to investigate the effect of potassium nitrate, garlic extract and onion extract on bud break, growth, yield and some chemical constituents of “Anna” apple (Malus sylvestris, Mill) variety. The trees were grown in loamy sand soil, and sprayed with six treatments (potassium nitrate 10%), garlic extract (20%), onion extract (20%), potassium nitrate (5%) mixed with garlic extract (10%), potassium nitrate (5%) mixed with onion extract (10%) and control. Generally, it was found that all studied growth parameters, date of flower bud break, percentage of bud break, fruit-setting ,fruit weight, fruit size, fruit number/tree, yield/tree (kg) and some chemical constituents of leaves (total chlorophyll ,total carbohydrates, total protein, nitrogen, phosphorous and potassium contents) and some chemical constituents of fruits (Total Soluble Solids (T.S.S.), T.S.S/ acid ratio, vitamin C, water content %, total free amino acids, total carbohydrates, total sugars and reducing sugars) were increased with the application of the different treatments. The best results were obtained from the treatments of potassium nitrate at 5% mixed with onion extract at 10%, potassium nitrate at 5% mixed with garlic extract at 10% and potassium nitrate at 10%. On the contrary, the same treatments decreased total acidity and total phenols in fruits as compared to the control. It could be recommended to use potassium nitrate at 5% in combination with onion extract or garlic extract at 10% for improving bud break, growth, yield and chemical constituents of apple trees or fruits

Improved Salinity Tolerance by Potassium Humate Fertilizer in Common Bean (Phaseolus vulgaris L., Cv. “Bronco”) Plants

The objective of this study is to assess the ameliorative impact of potassium humate (KH; 0, 100, and 200 kg per feddan) as soil amendments on the growth traits, green and dry yields characteristics, leaf photosynthetic pigments, chlorophyll fluorescence, and leaf contents of nutrients of common bean (Phaseolus vulgaris L., cv. “Bronco”) plants grown under saline soil conditions. To perform the study aim, two field trials were conducted at the Experimental Farm of Faculty of Agriculture, Fayoum University during the 2016 and 2017 summer seasons. The obtained results showed that, Na+ content was significantly declined, while the all other tested parameters such as growth characteristics (i.e., shoot length, number of leaves per plant, area of leaves per plant, and shoot fresh and dry weights), yield characteristics of green pods and dry seeds (i.e., average pod weight, number of pods per plant, pods weight per plant, dry seed weight per plant and 100-seed weight), leaf photosynthetic pigments (i.e., total chlorophylls, total carotenoids) contents and leaf chlorophyll fluorescence (i.e., Fv/Fm and PI), leaf contents of N, P, K+, and Ca2+, and the ratios of K+/Na+, Ca2+/Na+ and K++Ca2+/Na+ were significantly increased by the all KH treatments compared to the controls (without KH). The two KH treatments conferred, approximately, the same results. Therefore, results of this study recommend using KH at 100 kg per feddan to optimize the common bean performance in saline soils