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العنوان
Effect of forage barley grains pre-treatment on seedling growth and some anatomical traits under drought condition /
المؤلف
Mohamed, Hanan Khaleel Amrajaa.
هيئة الاعداد
باحث / حنان خليل إمراجع محمد
مشرف / محمود عبدالمنعم خفاجى
مشرف / زين العابدين عبدالحميد محمد
مشرف / سعد فاروق محمد حسين
الموضوع
Barley - Growth. Growth (Plants) Grain. Forage plants - Growth.
تاريخ النشر
2017.
عدد الصفحات
196 p. :
اللغة
الإنجليزية
الدرجة
ماجستير
التخصص
علوم النبات
تاريخ الإجازة
01/08/2017
مكان الإجازة
جامعة المنصورة - كلية الزراعة - Agricultural Botany Department
الفهرس
Only 14 pages are availabe for public view

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from 196

Abstract

This study was carried out in the Lab of Agric. Bot. Dept., Fac. of Agric., Mansoura Univ., during the growing season of 2015 and 2016 to investigate the effect of some priming treatments on grain germination, and seedling growth of barley under various levels of PEG-induced drought stress. The experiment was laid out in a CRD. The collected data were analyzed statistically at 5% level of probability. The most important results are summarized as follows : The First Experiment : All germination trails decreased with increasing PEG concentration up to30%. In most cases, all priming treatments significantly induced all mentioned characters except 15% PEG-6000 which significantly decreased germination percentage (G%), germination index (GI) and markedly decreased either germination energy (GE) or seedling vigor index. The grain priming in 1000 mg/l potassium nitrate gave the highest values of studied characters. Application of any priming agent counteracted the harmful effect of drought on germination trials studied, by increasing the germination characteristics as compared with non-primed under such drought stress levels. Seedling growth significantly decreased with with increasing drought stress up to 30%, meanwhile priming treatment in special 1000 mg/l potassium nitrate significantly increased it as compared with the control. Application of priming agent under drought stress counteracted the harmful effect of drought on germination and seedling growth as compared with un-priming treatment under such drought stress level. The Second Experiment : drought stress up to 20% significantly decreased emergence percentage, seedling growth, photosynthetic pigments, ion percentage in both shoot and root system, relative water content% as compared with control. all priming agent, in speciall, potassium nitrate at 1000 mg/l markedly increased emergence percentage, seedling growth, photosynthetic pigments, ion percentage in both shoot and root system, relative water content% as compared with un-priming treatment. All priming agents counteracted the harmful effect of PEG induced drought stress on emergence percentage, seedling growth, photosynthetic pigments, ion percentage in both shoot and root system, relative water content%, as compared with unpriming grain under such drought levels. The most effective in this regard was 1000 mg/l potassium. Proline concentration, total soluble carbohydrates, ascorbic acid, total soluble phenol markedly increased in both shoot and root system of barley with increasing drought stress level, or priming treatment as well as their interaction as compared with control. Membrane permeability significantly increased with increasing drought stress up to 20% PEG, meanwhile, priming treatment in special, 1000 mg/l potassium nitrate significantly decreased membrane permeability percentage. In most cases, all priming agents markedly decreased membrane permeability percentage as compared with non-primed control under such drought levels. Drought stress have a negatively impact on most leaf anatomical characters. The reduction values were obtained in thickness of leaf blade and dimension of main vascular bundle. Priming agents have a positively impact on the most of previous leaf anatomical characters and significantly increased them. Priming with any agents in special 1000 mg/l potassium nitrate in combination with drought stress level significantly increased most leaf anatomical features compared with untreated plants under the same drought stress level. Drought stress or priming treatment as well as their interaction increased the number of stomata on leaf adaxial surface and abaxial one as compared with control. Drought stress treated plants showed drastic changes and defoliation in chloroplasts, mitochondria and nucleus. Grain priming treatments under normal condition, showed a typical organelles ultrastructure with no or less significant changes. However, priming treatment under drought stress helped to alleviate the microorganelles damage. Conclusion : It could be recommended that for improving barley grain germination, seedling growth and vigor under normal or drought stress condition, we must prime barley grain before sowing in potassium nitrate at 1000 mg/l for 24 h.