Phenology of German Chamomile and its Changes under Different Irrigation Regimes and Plant Densities

In order to definite growth stages of Matricaria chamomilla L., 40 plants were planted with 200 × 200 cm distance from each other. To determine the phenology under different water stress condition and plant densities, an experiment was conducted in factorial based on randomized complete block design with two factors including irrigation at 4 levels (25, 50, 75, and 100 mm evaporation from pan class A), and plant density at 5 levels (cultivation in 30 cm rows with 5, 10, 15, 20 and 25 cm intra-row spaces) with three replications. Definition of growth stages including the maximum number of nodes, sub stems and tillers were 21, 20 and 14 that were occurred at 970, 1088 and 1088 oC growth degree-days, respectively. The numbers of nodes were 28.6, 30.0, 30.2 and 27.8, of sub stem were 19.2, 18.4, 19.8 and 18.4; and of tillers were 14.8, 14.0, 15.0 and 14.4 that were obtained from irrigation at 25, 50, 75, and 100 mm evaporation from pan, respectively. In the other hand, the number of nodes as follow 28.25, 29.00, 29.75, 29.75 and 29.00; sub stem as 17.50, 20.00, 20.75, 19.00 and 17.50; and tillers were 15.00, 13.50, 14.75, 14.00 and 15.50 that were obtained from 5, 10, 15, 20 and 25 cm intra-row spacing, respectively. Differences by irrigation on GDDs values were observed at the second harvest. However the earliest observation of flower and seed receiving at the first harvest occurred on 5 cm intra-row spacing. These changes were identical by GDDs for second harvest of flower, but with mild slope of reduction. There were no differences in number of leaves and tillers among irrigation levels and plant densities.


Introduction
Prior to any serious consideration of the chemical composition of chamomile, the botanical and taxonomical identity needs to be understand (Mann and Staba, 1992).Chamomile (Matricaria chamomilla L.), family Asteraceae, there so called German, Hungarian or small chamomilla is a native of Europe and is cultivated extensively in Hungary, Germany, Russia and Yugoslavia.In India M. chamomilla (Persian chamomilla, locally called 'Baboonaj') has been reported to grow in the plains.Matricaria has a wide domestic use, especially among the Germans (Singh, 1982).Chamomile is an annual with an erect or spreading height and usually attains a height of 50 to 65 cm and in some cases about 85 cm.The stem is glabrous, branched; leaves very green and smooth, 2-3 perinatiseet with segments short and very linear, giving the leaf finely dissected appearance.Head solitary, long peduncled, with white ray and yellow disc florets.Receptacle conic, elongated during fruiting (Singh, 1982;Salamon, 1992).The world market currently has German chamomile drug of various origin and therapeutically values.In the 1970s, plant material was evaluated by the content of essential oil and the content of chamazulene (Salamon, 1998).
The changes in the soil moisture regime can alter the root morphology and anatomy, the pore size distribution, and the angle of roots penetration, which affect root proliferation.The major types of stresses which potentially affect plant growth on a global basis are water (flooding and drought) stress (Pessarakli, 1999).In waterlogged soils, slowing down of shoot and root growth was more closely related to the declining O 2 concentration in the soil solution than to the concentration of dissolved inorganic nitrogen (Trought and Drew, 1980).Flooding is the saturation of the soil root zone with water.Flooding (water logging) occurs when inundation persists as a result of inadequate surface and/or subsurface drainage and the aeration status of the soil system decreases below critical ogy of German chamomile, 40 plants were planted with 200 cm distance from each other in 2003 and 2004.Statistical evaluation was performed using MSTATC software (Michigan State University, 1988).The effects of Irrigation regimes (I) and Plant density (D) as well as the interactions of these two factors were analyzed with the analysis of variance.The results of statistical analysis are expressed by F-values; asterisks indicate p-values: p*<0.05 and p**<0.01.The comparison of means carried out with SNK (Student-Neuman Keul's test).

Results and discussion
Definition of growth stages of Matricaria chamomilla L. at the experiment site in 2003 and2004, showed in Tab. 2. In this study, the maximum number of nodes (V n ), sub stems (S n ) and tillers (T n ) were 21, 20 and 14 at the GDDs of 970, 1088 and 1088 o C, respectively (Tab.1).
Means of vegetative and generative growth stages of German chamomile under irrigation regimes and plant distances on constant rows (plant density) showed on Tab. 2 and 3. Vegetative stages: V e , V c , V 1 , V 2 and V 3 were same in all treatments, after that and carrying out of irrigation and plant density treatments differences were showed.The numbers of node were 28.6, 30.0, 30.2 and 27.8 at the irrigation at 25, 50, 75 and 100 mm evaporation from class A pan, respectively.It seems excess water on I 1 and water deficit on I 4 lead to reduce number of nodes.Means of the number of sub stem were 19.2, 18.4, 19.8 and 18.4; and the number of tillers were 14.8, 14.0, 15.0 and 14.4 obtained from I 1 , I 2 , I 3 and I 4 , respectively.R 1 stage was 73 days after planting at I 1 and I 2 , but 66 days after planting at I 3 and I 4 .However, R 2 stage was 87 days after planting in I 1 and I 2 and 80days after planting in I 3 and I 4 .R 3a were occurred 87 days after planting in all irrigation regimes, but R 3 b were 113 days after planting for I 3 and I 4 and 111 days after planting for I 1 and I 2 .R 4a were occurred 105 days after planting in all irrigation regimes, but R 4b were 122 days after planting for I 1 , I 2 and I 3 that were 7 days later than I 4 .These results, any differences at the first harvest and differences at the second harvest, are due to ending a growth stage at the second stage while at the first one we cut the growth and harvest its flowers and seeds.Rs, flowering of sub stems occurred 80 days after planting at the I 4 , while it occurred 87 days after planting at the I 1 , I 2 and I 3 (Tab.2).It seems the strength stresses led to early observation on generative stages.
The number of nodes 28.25, 29.00, 29.75, 29.75 and 29.00; sub stem 17.50, 20.00, 20.75, 19.00 and 17.50; and tillers were 15.00, 13.50, 14.75, 14.00 and 15.50 obtained from D 1 , D 2 , D 3 , D 4 and D 5 , respectively.Initial of generative stage, R 1 was occurred 66 days after planting at the D 1 and D 5 that were 7 days earlier than D 2 , D 3 and D 4 .However occurrence of R 2 was 73 days after planting at the D 1 and D 5 like R 1 in comparison with D 2 , D 3 and D 4 .R 3a were occurred 84, 86, 87, 88 and 89 days after planting and R 4a limits.Water stress (drought) is also an important limitation to crop production.Reduction in photosynthetic activity and increases in leaf senescence are symptomatic of water stress and adversely affect crop growth.Water stress also reduces the net CO 2 assimilation (Pessarakli, 1999).
Plant density is invariably linked with yield, the more plant stands there are up to a certain limit, the higher the expected yield (Bertoia et al., 1998).The dominant production practice is for farmers to plant crops (cereals) at spacing in the range of 30-35 cm, which on average gives about 44.000 to 38.000 plants per hectare.In addition, in most irrigation schemes, water is not a limiting factor, what tends to happen is rather over-irrigation because of the abundance of water.Research has also shown that farmers apply on average twice the moisture consumptive use requirements of crops on each irrigation level.This is deleterious to crops and retards proper growth and subsequent yield.Farmers thus face the problem of knowing the correct plant density to sow and also the exact amount (or optimum amount) of water to apply, which amount to apply in areas of abundance and areas of scarcity (Sani et al., 2008).
This communication, based on a 2-year (2003 and 2004) field study, describes the drought susceptibility of 5 plant density of German chamomile, expressed in terms of plant phenology.The seeds of Matricaria chamomilla L. c.v. 'Bodegold' , a tetraploide variety were planted on 1 May both two year.Experiments carried out in factorial based on Randomized Complete Block Design with two factors, Irrigation and plant density.Irrigation regimes (I 1 , I 2 , I 3 and I 4 ) irrigation at 25, 50, 75 and 100 mm evaporation from class A pan, respectively) and plant density (D 1 , D 2 , D 3 , D 4 and D 5, cultivation in 30 cm rows with 5, 10, 15, 20 and 25 cm intra-row spaces, respectively) treatments have done at rosette stage.Plant growth was continuously monitored during the whole experimental period by mechanical control of weeds.However, to determine a complete phenol-were occurred 102, 103, 104, 105 and 108 days after planting in D 1 , D 2 , D 3 , D 4 and D 5 , respectively.But R 3b were 113 days for D 1 and D 2 , 114 days for D 3 and D 4 , and 115 days for D 5 , while R 4b for D 1 , D 2 and D 3 were 119 days and for D 4 and D 5 were 120 days after planting.Rs Stage was 87 days for D 1 , D 3 , D 4 and D 5 , and 94 days after planting for D 2 (Tab.3).Accumulative Growth Degree Days for German chamomile during growth season of experiment site was shown on Fig. 1. Results of ANOVA showed that GDDs for first harvests of flower and seed were not affected by irrigation regimes, but plant density had significant effect on them (P<0.01).Significant interaction between year and plant density showed different procedure of GDDs for first harvest of flower and seed (Tab.4).Despite of these significances, GDDs for first harvest of flower and seed have same trends, increasing with reducing plant density in both 2 years (Fig. 2).We found the maximum amounts of GDDs at the first harvest of flower (1075) and seed (1409) belonged to D5 in which declined with reducing intra-row distances and received the minimum amounts for flower (1011) and seed (1300) harvest in D1 (Fig. 3).At the second harvest, GDDs for harvest of flower affected by irrigation regime and plant density (P<0.01),But the effect of plant density was non-significant for seed harvest (Tab.4).Maximum amounts of GDDs at the second harvest of flower belonged to I 1 and I 2 and the minimum amount obtained from I 3 and I 4 .These values obtained at I 3 and I 4 for maximum and minimum, respectively.Comparisons of means showed the same procedures on GDDs like one of the first harvest of flowers affected by different plant density (Fig. 2).Overall differences by irrigation on GDDs values observed at the second harvest.Water stress at the strength level led to earlier occurrence of receiving both flower and seed.However the earliest observation of flower and seed receiving at the first harvest occurred on the highest density of plant.It seems that increasing the distances between plants provide a condition to branching and great vegetative growth.These changes were the same with GDDs for second harvest of flower, but with mild Appearance of 4 th node on stem (6 th leaf ) 437 V 5 Appearance of 5 th node on stem (7 th leaf ) 484 V 6 Appearance of 6 th node on stem (8 th leaf ) 531 V 7 Appearance of 7 th node on stem (9 th leaf ) 580 V 8 Appearance of 8 th node on stem (10 th leaf ) 600 V 9 Appearance of 9 th node on stem (11 th leaf ) 620 V 10 Appearance of 10 Results showed no differences of the number of leaves and tillers among irrigation levels with means 27.377 and 12.683, respectively.But, plant density had significant (P<0.05) and non-significant effect on the numbers of leaves and tillers.Despite of this significance all levels of plant densities had same numbers of leaves and tillers under among plant densities.However, there were significant interaction between irrigation and plant density on the numbers of sub stem (Tab.4).Results indicated that levels of each factor in other factor had a same trend of the numbers of sub stem (Tab.5).

Tab. 5 .
Means of interaction between irrigation regimes and plant density on the maximum numbers of sub stem per

Fig. 2 .Fig. 3 .
Fig. 2. Means of interaction between year and plant density on GDDs of first harvest of flower and seed.The same letters show non-significant differences Tab. 1. Definition of growth stages of Matricaria chamomilla L. at the experiment site in2003 and 2004