تقييم محاليل هوكلاند المحورة بدلالة استجابة تجذير عقل الماش (Phaseolus aureus Roxb.)

Evaluation of Modified Hoagland solutions in terms of rooting response of Mungbean cuttings (Phaseolus aureus Roxb.)

The evaluation of modified Hoagland solutions complete , lacking for Macro and micro elements, individually and substituted by Silicon (one of benefical elements) as alternative in terms of rooting response of fresh and aged mungbean cuttings has been studied . Stem cuttings (experimental system) were taken from 10 days – old light grown seedlings in growth chamber under controlled conditions [continuous light , light irradiance (1600-1800 lux) , temperature (25 + 1 ^oC) and relative humidity (60-70%) ] . The results revealed the followings :

1- A significant decline in rooting response (number and lengths of roots) of fresh and aged mungbean treated with modified Hoagland Solutions lacking for Macro – and Micro elements (HSLF) and also lacking for the addition  of silicon , except solutions lacking for Boron and Manganese substituted by silicon which developed a higher roots number by percent increase (10.03% , 22.29%) and (14.79% , 38.04%) respectively while a decline in number and lengths of roots in solution lacking for zinc and potassium substituted by silicon compared to the control , (complete Hoagland solution) .

2- A decline of free auxin (Free IAA) significantly in primary leaves of fresh and aged mungbean cuttings , except the increase in hypocotyl of fresh cuttings , whereas an increase of free gibbrellin and cytokinin content in leaves and hypocotyl fresh and aged cuttings treated with HSLF elements and olso lacking and addition of Silicon , with a significant decrease of free Abscisic acid content (ABA) , except an increase in hypocotyls of fresh cuttings compared to the control.

3- Increasing of Bound auxin content in fresh cutting leaves and hypocotyl of aged cuttings significantly at probability level (0.05) in terms of L.S.D , with a significant decline in primary leaves for aged cuttings and Hypocotyl of fresh cuttings of modified Hoagland solutions , whereas a decline of free gibbrellin and cytokinin was occurs in leaves and hypocotyl of freesh and aged mungbean cuttings , axcept the increase in hypocotyl of aged cuttings , in addition to a significant decline for Bound abscsic acid content of fresh cutting leaves and Hypocotyl of aged , except the increase in primary leaves for aged and Hypocotyl of fresh cuttings compared to the control.

4- A significant decline of total auxin content in leaves and hypocotyl of fresh and aged cuttings treated with HSLF elements , except the significant increase in fresh cutting leaves treated with SLF and substituted by silicon , in addition to a decline of total gibberellin and cytokinin in leaves and hypocotyl – fresh and aged cuttings , except hypocotyl of fresh cuttings and also a significant decline in a total abscsic acid content of leaves and hypocotyl fresh and aged cuttings , except the increase in hypocotyl fresh cuttings in all SLF elements and substituted with Silicon compared with the control.

5- Treatment of primary leaves of fresh cuttings SLF elements caused a significant decline in total chlorophyll , with an increase of chlorophyll content of aged cuttings treated by SLF elements substituted with Silicon.

6- A significant decline of transperation rate for fresh cutting leaves treated by SLF elements and addition of Silicon while increase in its rates of aged cuttings.

7- Treatment of leaves and hypocotyl fresh mungbean cuttings of modified Hoagland solution / lacking for elements and also lacking for and substituted by Silicon caused to a significant decline in total carbohydrates content , at the same time increased the content in leaves and hypocotyl of aged cuttings compared to the control.

8- A deline of protein content for fresh and aged mungbean cuttings , in addition to an increase content in hypocotyl of fresh and aged treated by SLF elements and also lacking for and substituted by silicon compared the control.

9- The application of modified Hoagland solution lacking for and substituted by Silicon caused a significant decline of non enzymatic anti – oxidants : proline and total ascorbate content in leaves and hypocotyl aged cuttings , at the same time increased the content in leaves and hypocotyl of fresh cuttings compared to the control.

10- The application of modified Hoagland solutions caused a decrease in the activity of enzyme catalase (CAT) (enzymatic anti – oxidants) in primary leaves and hypocotyl of fresh and aged mungbean cuttings , except the increase in hypocotyl aged cuttings , at the same time increased the activity of enzyme super oxide dismutase (SOD) in leaves and hypocotyl of fresh and aged cuttings , except fresh leaves treated by SLF elements , and also increasing the activity of Indole -3- acetic acid oxidase (IAAO) in leaves and hypocotyl of fresh and aged cuttings , except the decline of enzyme activity in aged cuttings of SLF elements and substituted by Silicon compared to control.