الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 105 |  |  |
| | | from | 105 | | |
Abstract
A laboratory experiment was performed at Agronomy Department Laboratory of Seed Testing, Faculty of Agriculture, Mansoura University, Egypt, during October month, 2022. The objective of this laboratory experiment was to study the effect of some natural substances at various levels to improve germination and seedlings vigor of sugar beet Hossam cultivar under salinity stress conditions. The laboratory experiment was conducted in factorial experiment in completely randomized design (CRD). The first factor included seven salinity levels as sodium chloride (NaCl) as follows: 1. Without salinity (control treatment) 0 mM of NaCl. 2. 20 mM of NaCl. 3. 40 mM of NaCl. 4. 60 mM of NaCl. 5. 80 mM of NaCl. 6. 100 mM of NaCl. 7. 120 mM of NaCl. The second factor included eleven soaking seed treatments in some natural substances at various levels for 18 hours as follows: 1. Without soaking (untreated ””control treatment””). 2. Soaking in distilled water. 3. Soaking in moringa leaf extract (MLE) at the level of 100 ml/L. 4. Soaking in moringa leaf extract (MLE) at the level of 200 ml/L. 5. Soaking in moringa leaf extract (MLE) at the level of 300 ml/L. 6. Soaking in algas extract (AE) at the level of 75 ml/L. 7. Soaking in algas extract (AE) at the level of 150 ml/L. 8. Soaking in algas extract (AE) at the level of 225 ml/L. 9. Soaking in yeast extract (YE) at the level of 100 ml/L. 10. Soaking in yeast extract (YE) at the level of 150 ml/L. 11. Soaking in yeast extract (YE) at the level of 200 ml/L. Random sample of 400 seeds per each treatment were sown on top filter paper in sterilized Foam-dishes (20 × 30 cm). Each Foam-dish contain 25 seeds, and four Foam-dishes kept close together and assessed as though they were one 100 – seeds replication under the environmental conditions of Laboratory for Seed Testing in Agronomy Department, Faculty of Agriculture, Mansoura University, Egypt at the first week of October, 2022 as the rules of International Seed Testing Association (ISTA, 1996). A- Germination parameters: 1- Germination percentage (%). 2- Speed germination index (SGI). 3- Germination index (GI). 4- Co-efficient of germination (CG). 5- Mean germination time (MGT). 6- Energy of germination (EG). 7- Abnormal seedlings percentage (%). 8- Rotten seeds percentage (%). B- Seedling parameters: 1- Root length (cm). 2- Shoot length (cm). 3- Seedling length (cm). 4- Seedling vigor index (SVI). • The most important results obtained from this investigation can be summarized as follows: 1- Effect of salinity levels: from obtained results of this study it could be noticed that significant differences were detected in germination parameters i.e. germination percentage, speed germination index (SGI), germination index (GI), co-efficient of germination (CG), mean germination time (MGT), energy of germination (EG), abnormal and rotten seeds percentages as well as seedling parameters i.e. root length, shoot length, seedling length and seedling vigor index (SVI) among studied salinity levels (0, 20, 40, 60, 80 and 120 mM of NaCl). Overall, increasing salinity levels from 0 to 20, 40, 60, 80 and 120 mM of NaCl significantly reduced germination percentage, speed germination index (SGI), germination index (GI), co-efficient of germination (CG), mean germination time (MGT), energy of germination (EG), root length, shoot length, seedling length and seedling vigor index (SVI) and increased abnormal and rotten seeds percentages of sugar beet. The highest values of germination percentage, speed germination index (SGI), germination index (GI), co-efficient of germination (CG), mean germination time (MGT), energy of germination (EG), root length, shoot length, seedling length and seedling vigor index (SVI) and lowest values of abnormal and rotten seeds percentages of sugar beet were obtained from the control treatment (without salinity stress), followed by salinity stress at the level of 20 mM of NaCl, and then salinity stress at the level of 40, 60, 80 and 100 mM of NaCl. While, the lowest values of germination percentage, speed germination index (SGI), germination index (GI), co-efficient of germination (CG), mean germination time (MGT), energy of germination (EG), root length, shoot length, seedling length and seedling vigor index (SVI) and highest values of abnormal and rotten seeds percentages of sugar beet were produced from the highest salinity level of 120 mM of NaCl. 2. Effect of soaking seed treatments in some natural substances: Averages of germination parameters i.e. germination percentage, speed germination index (SGI), germination index (GI), co-efficient of germination (CG), mean germination time (MGT), energy of germination (EG), abnormal and rotten seeds percentages as well as seedling parameters i.e. root length, shoot length, seedling length and seedling vigor index (SVI) of sugar beet significantly affected by soaking seed treatments in some natural substances at various levels for 18 hours i.e. without soaking (untreated ””control treatment””), soaking in distilled water, moringa leaf extract (MLE) at the levels of 100, 200 and 300 ml/L, algas extract (AE) at the levels of 75, 150 and 225 ml/L and yeast extract (YE) at the levels of 100, 150 and 200 ml/L. The obtained results clearly indicated that soaking sugar beet seeds in moringa leaf extract (MLE) at the level of 300 ml/L surpassed the other studied seed treatments in some natural substances in germination and seedlings parameters and resulted in the highest values of germination percentage, speed germination index (SGI), germination index (GI), co-efficient of germination (CG), mean germination time (MGT), energy of germination (EG), root length, shoot length, seedling length and seedling vigor index (SVI) and lowest values of abnormal and rotten seeds percentages of sugar beet. It was followed by soaking sugar beet seeds in yeast extract (YE) at the level of 200 ml/L. The arrangement of other studied soaking seed treatments in some natural substances was as follows; soaking in algas extract (AE) at the level of 225 ml/L, moringa leaf extract (MLE) at the level of 200 ml/L, yeast extract (YE) at the level of 150 ml/L, moringa leaf extract (MLE) at the level of 100 ml/L, yeast extract (YE) at the level of 100 ml/L, algas extract (AE) at the level of 150 ml/L, algas extract (AE) at the level of 75 ml/L and distilled water. Whereas, the lowest values of germination percentage, speed germination index (SGI), germination index (GI), co-efficient of germination (CG), mean germination time (MGT), energy of germination (EG), root length, shoot length, seedling length and seedling vigor index (SVI) and highest values of abnormal and rotten seeds percentages of sugar beet were produced from without soaking (untreated ””control treatment””). 3. Effect of interaction: With respect to the interaction between salinity levels and soaking seed treatments in some natural substances at various levels, the obtained results clearly showed that germination parameters i.e. germination percentage, speed germination index (SGI), germination index (GI), co-efficient of germination (CG), mean germination time (MGT), energy of germination (EG), abnormal and rotten seeds percentages as well as seedling parameters i.e. root length, shoot length, seedling length and seedling vigor index (SVI) of sugar beet were significantly affected by the interaction between salinity levels and soaking seed treatments in some natural substances at various levels. from obtained results, the highest values of germination percentage, speed germination index (SGI), germination index (GI), co-efficient of germination (CG), mean germination time (MGT), energy of germination (EG), root length, shoot length, seedling length and seedling vigor index (SVI) and lowest values of abnormal and rotten seeds percentages of sugar beet were recorded when soaking sugar beet seeds in moringa leaf extract (MLE) at the level of 300 ml/L under without salinity stress (control treatment). However, soaking sugar beet seeds in yeast extract (YE) at the level of 200 ml/L under without salinity stress ranked after previously mention interaction treatment, and followed by soaking sugar beet seeds in algas extract (AE) at the level of 225 ml/L, moringa leaf extract (MLE) at the level of 200 ml/L, yeast extract (YE) at the level of 150 and algas extract (AE) at the level of 150 ml/L under salinity stress of 20 mM of NaCl. On the other hand, the lowest values of germination percentage, speed germination index (SGI), germination index (GI), co-efficient of germination (CG), mean germination time (MGT), energy of germination (EG), root length, shoot length, seedling length and seedling vigor index (SVI) and highest values of abnormal and rotten seeds percentages of sugar beet were recorded from control treatment (without soaking seeds in natural substances) under salinity stress of 120 mM of NaCl. CONCLUSION : Purposeful to improve germination and seedlings vigor of sugar beet Hossam cultivar under salinity stress conditions, it could be recommended that soaking seeds for 18 hours in moringa leaf extract (MLE) at the level of 300 ml/L or yeast extract (YE) at the level of 200 ml/L or algas extract (AE) at the level of 225 ml/L.