الفهرس 
Chamomile plantOnly 14 pages are availabe for public view
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Abstract
The objective of this work was to apply natural sources of nutrition (Azolla and compost) and different methods of addition with a reduction of mineral nitrogen fertilizer in sandy soil and its effect on vegetative growth, the yield of flower heads, the macronutrients (NPK), nitrate and nitrite contents, total phenolic, antioxidant activity and the volatile oil content and composition of chamomile plant. Then, define the best fertilizer treatment which achieved the highest yield production with increment in active substances under sandy soil.
For this goal two pot experiments were conducted during 2010/2011 and 2011/2012 seasons in the experimental farm of Faculty of Agric., Ain Shams University. Fresh or dried materials of Azolla (and/or) ammonium nitrate or compost were applied as follow:
T1- Ammonium nitrate at recommended dose (control)
T2- Compost
T3- Dry Azolla (DA)
T4- 75% DA + 25% ammonium nitrate
T5- 50% DA + 50% T1
T6- Fresh Azolla (FA) as a green manure
T7- 75% FA + 25% T1
T8- 50% FA + 50% T1
T9- Spray Azolla (SA) as foliar
T10- 75% SA + 25% T1
T11- 50% SA + 50% T1
T12- 50% Compost + 50% FA
T13- 50% Compost + 50% T7
T14- 50% Compost + 50% T8
T15- 50% Compost + 50% SA
T16- 50% Compost + 50% T10
T17- 50% Compost + 50% T11 The response of Chamomile plants to these treatments was tasted to reach to the best treatments which achieved the highest yield production with increment in active substances under sandy soil.
Growth characters
1- seasonal changes of plant height, branches number, shoot fresh and dry weights of chamomile plants was recorded during the two successive sampling dates 60 and 100 days (after transplanting) generally tended to increase with advancement of the age in both seasons.
2- Significant increase was achieved with dry Azolla (DA) in plant height, number of branches/plant and fresh & dry weights above the rest treatments in both seasons.
3- Fresh Azolla (FA) or spray Azolla extract (SA) alone detected significant decrement in plant height against the control (T1) in both seasons.
4- No significant differences were achieved between FA treatments and the same treatments of SA with a reduction in plant height against the control in the 2nd season.
5- Apart from number of branches/plant in the 2nd season at the middle of flowering period, FA (T6) significantly diminished the number of branches/plant and fresh & dry weights below the control while there are no significant differences with the application of SA (T9) in the two growing seasons.
6- Addition 25% or 50% ammonium nitrate to both FA or SA as well SA alone gained significant increase in the number of branches/plant against the control (T1) at the middle of flowering period in the both seasons.
7- SA treatments stimulated chamomile fresh and dry weights more than FA treatments. On the other hand, raising mineral nitrogen level with FA or SA led to increase weight.
8- Positive response was achieved with compost + Azolla treatments in plant height; number of branches/plant and fresh & dry weights against the same treatments without compost and the highest values were recorded with compost + SA treatments in both seasons.Harvesting
1- Dry Azolla (T3) induced the highest number of flower heads/plant above the other treatments in both seasons.
2- Addition of 50% ammonium nitrate to 50% FA (T8) led to significant increase in inflorescences number/plant above the control (T1) in both seasons.
3- SA treatments achieved significant increments in chamomile flower heads number above the control in the two growing seasons.
4- Application of compost with FA or SA gained significant increase in flower heads number/ plant above the same treatments without compost as well compost alone (T2).
5- Addition of compost to 50% FA (T14) and 50% SA (T17) increased significantly flower heads number/plant against T12 and T15 respectively in both seasons to reach 112.5 & 134.3 against 93.7 & 113.5 respectively in the 1st season and 119.3 & 144.3 against 94.3 & 122.3 respectively in the 2nd season.
6- DA treatments have positive effect on inflorescences development, since the picking started earlier than the rest treatments for about 2-3 weeks.
7- Apart from FA treatments, number of inflorescences/picking increase gradually with picking dates and then decrease at the end of picking for about 1-2 weeks in both seasons.
8- DA treatments gained maximum yield production followed by SA + compost treatments in both seasons.
9- SA treatments achieved higher total number and fresh & dry weights of flower heads/treatment than FA treatments in the two growing seasons.
10- Application of compost either with FA or SA led to an increment in flower heads number and fresh & dry weights/treatment than the same treatments without compost or compost alone in both seasons.
11- DA treatments achieved the highest inflorescences fresh and dry weights/treatment in the two growing seasons. 12- The inflorescences fresh and dry weights/picking parallel to the number of inflorescences/picking.Chemical constituents
Shoot (vegetative organs)
1- The percentage of nitrogen, phosphorus and potassium of the different treatments decreased gradually in chamomile shoot with advancement of age in both seasons.
2- DA treatment (T3) stimulated NPK percentage against the control in the two growing seasons.
3- Foliar applications of Azolla extract (SA) initiated an increase of NPK content above the same treatments of FA in both seasons.
4- Applications of compost with SA had positive effect on NPK than, the same treatments of compost with FA and the highest increment was achieved with T17 during the two successive seasons.
The inflorescences
1- The highest nitrate and nitrite contents were achieved in case of inorganic fertilization (control) and the reverse was true in case of DA (T3) in both seasons.
2- Addition of 50% ammonium nitrate with 50% SA (T11) reduced nitrate and nitrite contents than the same treatment with FA (T8) in the two growing seasons.
3- Application of 50% compost either with 50% FA or 50% SA led to decrease nitrate and nitrite contents than the same treatments without compost and compost treatment singly (T2)
4- Reduction of nitrate and nitrite contents were recorded with compost treatment (T2) against the control (T1).
5- Generally, nitrate and nitrite levels in all treatments under investigation are within the legal limits, therefore, this type of German chamomile inflorescences extract is safe for human consumption.6- The antioxidant activity of chamomile inflorescences extracts during the harvesting stage run parallel that detected in total phenolic content in both seasons.
7- The highest total phenolic content and antioxidant activity were gained with DA while, the lowest contents were recorded with the control in the two successive seasons.
8- 50% SA either with compost (T17) or without compost (T11) increased total phenolic content and antioxidant activity as compared with the same treatments of 50% FA in both seasons.
9- Compost treatment (T2) stimulated total phenolic content and antioxidant activity against mineral fertilization (T1) in the two growing seasons.
10- The highest VO% was achieved with DA through six picking periods in every season. Meanwhile, the picking weeks eight and nine recorded the highest VO content in both seasons.
11- VO content increased according to apply different nitrogen sources in the following order: DA> 50% compost + 50% SA>50% compost + 50% FA > 50% SA > 50% FA > control > compost in both seasons.
12- The medicinal values of the plant material were evaluated by the content of volatile oil. The quality of blue VO is determined by its colour. AS the name indicates, bluer the oil better is the quality because blue colour serves as the chemical marker for the presence of terpenoids and flavonoids, chiefly chamazulene and α-bisabolol and its oxides.
13- All treatments recorded high percentage of chamazulene and α-bisabolol and its oxides. The values were 85.64- 97.69% in the 1st season and 88.90-98.09% in the 2nd one.
14- The highest percentage of chamazulene was achieved with DA (T3) followed by compost + 50% SA (T17) in both seasons. Meanwhile, the highest percentage of α-bisabolol and its oxides was detected with compost treatment (T2) in the 1st season and 50% FA (T8) in the 2nd season.15- The highest percentage of total chamazulene and α-bisabolol derivatives was obtained with compost (T2) and DA (T3) for both seasons respectively.
16- Generally, the quality of all treatments is better but regarding to the quantity and quality of chamomile VO, the best treatment was detected with dry Azolla.