![]() | Only 14 pages are availabe for public view |
Abstract Effect of some micronutrients on some economic plants Three experiments were conducted in this study, two of them at the Experimental Station of Micronutrients Project in National Research Centre, Giza, Egypt, under greenhouse condition using sand culture technique, to study the effect of Fe, Mn and Zn on plant growth and some morphological characters of sunflower ,Helianthus annuus (L.) Giza 1) and squash ’Cucurbita gem- Eskandarani). The third experiment was carried out at Plant Nutrition Institute, Hannover University, Hannover, Germany, under growth chamber condition using water culture technique, to study the mobility and remobility of manganese applied to the older leaves of barley ,Hordeum vul(Jare (L.) Baroness) to investigate the ability of this varity of barley to managenese uses in physiological functions- I. Sunflower experiment under greenhouse conditions: 1- The growth of sunflower plants responsed to soil applications of Fe, Mn and Zn which the total weight of plant increased in the second stage (40 days after planting) than the first stage (21 days after planting) whereas the ratio of shoot dry weight to root dry weight incresed only with iron and zinc in the same stages of growth. 2- Generally, the assimilation rate was decreased in both iron and Manganese treatments in the two growth stages because of the increasing of total leaves area the total dry weight of leaves and the contrast was happened with zinc treatment in the same stages of growth. 3- There were a correlation between leaf area and both of shoot dry weight and total dry weight of plant also between root dry weight and shoot dry weight in both growth stages with the three elements. The root length had a positive effect with shoot dry weight only in the first stage with the three elements, whrease this effect was only in the second stage with manganese. The root size had a positive correlation with shoot dry weight in both stages of growth with iron and manganese treatments whereas with zinc treatment, the positive correlation was only in the first stage. 4- Iron addition : A) In the first stage of growth, iron addition with 5.6 ppm concentration led to the highest increase of total dry weight / plant, dry weight of roots, dry weight of shoots, leaf area, number of leaves and stem length. B) In the second stage of growth, iron addition with 11.2 ppm concentration led to the highest root and shoot dry weight and rood size wherease 33.6 ppm gained the highest leaf area and number of leaves 5- Manganese addition: A) In the first stage of growth, the concentration of 0.55 ppm gained the highest increase in root and shoot dry weights, Leaf area, number of leaves and stem length. B) In the second stage of growth, the rate of 1.10 ppm led to the highest root and shoot dry weights also for the total dry weight of plant and leaf area 6- Zinc addition: A) In the first stage of growth, Zinc addition at 65 ppb gained the highest increase of shoot and total dry weight, leaf area, number of leaves, stem length and root size. B) In the second stage of growth, Zinc addition at 260 ppb led to the highest increase in total dry weight, leaf area and number of leaves. 7- The uptake of the three elements was increased with advancing of plant age under the there elements treatments. The roots showed the highest uptake of iron, while leaves showed the highest uptake of manganese . Leaves showed the highest zinc uptake in the first stage of growth wherease stems showed that the highest uptake in the second stage. _ Iron addition : (stage 1) : The highest uptake of iron, manganese and zinc obtained with 5.6 ppm under the treatments of three elements. (stage II) : Iron addition at 5.6 ppm gained the highest iron uptake wherease 11.2 ppm led to the highest manganese and zinc uptake under the effect of the three elements. _ Manganese addition : (stage I) : The highest iron and zinc uptake were obtained with 0.55 ppm wherease 2.20 ppm gained the highest manganese uptake under the effect of the three elements. (stage II) : The highest iron and zinc uptake were gained with 0.55 ppm wherease 1.10 ppm was gained the highest manganese uptake under the effect of the three elements. Zinc addition: (stage I) : The highest iron, managanese and zinc uptake were obtained with 65 ppb under the effect of the three elements. (stage II) : The treatment of zinc with 65 ppb led to highest iron and manganese uptake wherease 260 ppb gained the highest zinc uptake under the effect of the three elements. 8- The treatment with any element of using elements led to change the absorption rates of the other elements by the plant and change the element balance in the plant. 9- Generally, the treatments of iron and zinc were highly effectedron nitrate reductase activity in leaves but the opposite were in roots, also the enzyme activity was created under some application and disappeared in other treatments. II. Squash experiment under greenhouse conditions 1- The growth of squash plants responded to soil applications of Fe, Mn and Zn which the total dry weight of plant and the ratio of shoot to root increased in the second stage than in the first stage. 2- The assimilation rate in iron treatment decreased in both stages of growth due to the increasing of total leaves area to total dry weight of leaves wherease, this rate increased in manganese treatment in both stages. In case of zinc, this rate was increased in the first stage and decreased in the second stage. 3- There were a positive correlation between leaf area and shoot dry weight also between root size and root dry weight and shoot dry weight in both stages of growth for the three elements whereas, there were a positive correlation between leaf area and total dry weight of plant also between root length and shoot dry weight only in the second stage for the three elements. 4- Iron addition: A) In the first stage of growth, the highest increase in total dry weight of plant gained with iron addition at 5.6 ppm B) In the second stage of growth, iron addition at 11.2 ppm concentration led to the highest increase in the majority of estimated growth characters. 5_ Manganese addition: A) In the first stage of growth, the treatment ofMn at 0.55 ppm led to the highest root size, leaves area and number of leaves whereas 1.10 ppm gained the highest shoot dry weight and total dry weight. B) In the second stage of growth, Manganese addition at 1.10 ppm led to the highest increase of shoot, total dry weight / plant and foot length whereaser2.20 ppm gained the highest increase of root size and leaf area. b) Zinc addition: A) In the first stage of growth, zinc addition with 65 ppb gained the highest increase of shoot and total dry weight / plant. B) In the second growth stage, zinc addition with 130 ppb gained the highest response for the majority of growth characters. 7- The uptake of the three elements increased with advancing the age under the three elements treatments. In the first stage, the roots were the highest uptake if iron and leaves were the highest uptake of manganese under the effect of the three element whereas the leaves were the highest uptake of zinc under the effect of iron only and the stems were the highest uptake of zinc under the effect of manganese and zinc treatments. In the second stage the leaves were the highest uptake of iron, manganese and zinc - Iron addition: (stage I) : The highest uptake of iron was obtained with 5.6 ppm whereas the highest uptake of manganese and zinc were obtained with 11.2 ppm (stage II) : The concentration of iron with 5.6 ppm gained the highest iron and zinc uptake, - Manganese addition: (stage I) : The concentration of manganese with 0.55 ppm gained the highest iron uptake, 3.30 ppm obtained the highest manganese uptake wherease 1.10 ppm gained the highest zinc uptake. (stage II) : The same results and trend were obtained - Zinc addition: (stage I) : The concentration of zinc at 65 ppb led to the highest iron uptake, the highest manganese uptake obtained with 260 ppb wherease 130 ppb gained the highest zinc uptake. (stage II) : The same trend was obtained 8- The treatment with different used elements led to change in the absorption rates of the other elements inside the plant and change in element balance. 9- The three elements, Fe, Mn and Zn highly increased the activity of nitrate reductase enzyme in leaves wherease Fe and Zn did not show clear effect on the activity in roots. Only manganese slightly affected the enzyme activity in roots. III. Barley experiment under growth chamber conditions Studing the mobility of manganese from nutrient solution to roots and shoots, the obtained results cleared that : _The total dry weight of plants increased untile the third sample (26 days after transferring) then was decreased. - The ratio of shoot dry weight to root increased un tile the third sample (26 days after transferring) then was decreased. _The length of leaves blades increased with advancing the plant age Mn-amount of old leaves blades was less than small leaves blades - Mn-amount of stems was decreased _Mn-amount of roots was less than in shoots All these results indicated that manganese translocated from roots to shoots and from stems and old leaves blades to small leaves blades but this translocation was not enough to prevent development and appearance of manganese deficiency symptoms-Also with studing manganese remobility from leaves by using leaf application with painting method on fourth leaf, the results cleared that _ There were no differences in dry weights of different parts of plant or shoots as total in treated or untreated plants. _There were no differences in length of leaf blade with application or without leaf application _Mn-concentration increased in stem indicating that the Mn of treated leaf blade translocated to stem _Mn-concentration increased in root indicating that Mn of leaf blade moved also to the roots. Mn-concentration and its accumulated amount in the young leaf in treatment case were higher than control plants. All these results indicated that there is a possibility for Mn remobility from old leaves blades to young leaves blades, stems and roots. In other words, Mn remobility and its translocation from treatment leaf to other different other plant parts which concluding Mn translocation to the plant top (leaves) and as well as to roots were possible. |