INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume, No, 11 Copyright All rights reserved Integrated Publishing Association Research article ISSN 97 Akhtar Inam 1, Seema Sahay, Firoz Mohammad 1- Department of Botany, Women s College, A.M.U., Aligarh - Department of Botany, Physiology & Environmental laboratory, A.M.U., Aligarh sahayseema7@gmail.com doi:.88/ijes. ABSTRACT In two field trials conducted at Aligarh (India), K content was studied in two varieties each of radish and turnip, grown under three regimes of nitrogen (, 15 and kg ha -1 ). The number of leaves and dry matter content of tops and roots of both crops increased with increasing doses of N. With the increase of N fertilizer, radish biomass production, economic output and the root yield increased with the increase of economic output per kg of nitrogen from the negative to a positive correlation, and the growth yield is also growing. Appropriate amount of nitrogen fertilizer increased the plant's largest leaf length, maximum number of photosynthetic leaves, tops and root dry matter accumulation in various organs in radish and turnip varieties, showed a positive correlation between nitrogen deficiencies reduced dry matter accumulation amount. K content also increased with increasing doses of N, with kg ha -1 giving the highest value. Local variety of each crop possessed comparatively less K content. Maximum K content was noted in Pusa Rashmi (radish) and Snow Ball (turnip) grown with kg ha -1. At early stage, K content was more in tops, but as the plants grew the content became higher in roots. Keywords: K content, N application, biomass, radish, turnip. 1. Introduction Potassium stimulates plant growth, including that of storage organs, by virtue of its stimulating effect on various processes for example photosynthesis, protein synthesis, translocation of food from source to sink and cell extension (Haeder et al., 1973; Foster and Beringer, 1983; Marschner, 198). Thus, its increased concentration in plants would be expected to improve growth and yield. Studies have shown that nitrogen application influences the mineral content of plants to a great extent (Fridgen and Vaico, ; Lu et al., 5). Root crops namely radish and turnip being a rich source of carbohydrates, minerals and vitamins, were considered suitable ti study the K content and its distribution in leaf and root in addition to growth yield as influenced by various regimes of nitrogen.. Materials and Methods The two field experiments, one on Radish (Raphanus sativus L.) and the other on turnip (Brassica rapa L.) were conducted at the Agriculture Farm of the Aligarh Muslim University, Aligarh (India) according to a factorial randomized block design. The sandy loam soil of field used for the trial on radish (Experiment 1) and turnip (Experiment ) respectively had ph (1:)-8.5 and EC (1:) -.8 and.8 dsm -1, available N- 3. and 33.5 kg N ha -1, P-. and. kg P ha -1 and K- 9. and 11. kg K ha -1, three levels of N, viz., 15 and kg ha -1, along with a uni8form basal dose of P ( kg ha -1 ) and K (5 kg ha -1 ), were applied to two varieties each of radish (Pusa Rashmi and local) and turnip (Snow Ball and Received on September 11 Published on November 11 3
local). Leaf number per plant, dry weight of tops and root and K content of tops and root were studied at 35, 5 and 5 days after sowing (d) in radish and at 35, 5 and 8 d in turnip. K was estimated with the help of AIMIL flame photometer using the filter for potassium. The data were analyzed statistically according to Panse and Sukhatme, (197). 3. Results and Discussion The data (Figure 1 and : Table 1 and ) reveal that the effect of N doses, their interaction with varieties and varietal difference on leaf production, top and root dry weight and leaf and root K content of radish and turnip at various growth stages were mostly significant (p=.5). In both radish and turnip, leaf production as well as dry weight and K content of tops and roots increased with increasing levels of N at most stages studied (Fig 1,, 3, : Table 1 and ). Leaf production (number/plant) 1 1 8 N (kg/ha) 15 N (kg/ha) 1 N (kg/ha) Pusa Rashmi Local 1.8* 1.53*.3*.71*.557*.55* 5.119* Top fresh weight (g/top) 3 1.1* 1.13* 1.755* 1.98* 1.3* Root fresh weight (g/root) 18 1 1 1 8 1.51*.1* 1.*.851* 1.7* 35d 5d 5d Sampling stages.93*.73* 1.31* Figure 1: Effect of basal doses of N on leaf production, top and root fresh weight in two varieties (Pusa Rashmi and Local) of radish at three stages of growth International Journal of Environmental Sciences Volume No., 11 31
N (kg/ha) 15 N (kg/ha) 1 N (kg/ha) Pusa Rashmi Local 5 Top dry weight (g/top) 3.*.8*.37*.98*.79* 1 1 1.99* Root dry weight (g/root) 8.31*.19*.5*.5*.13*.71* 1.39* 1.13* 35d 5d 5d Sampling stages Figure : Effect of basal doses of N on top and root dry weight in two varieties (Pusa Rashmi and Local) of radish at three stages of growth.the highest dose ( kg ha -1 ) invariably gave the maximum value. International Journal of Environmental Sciences Volume No., 11 3
It need not to be emphasized that N and K are among the three important nutrients required by plants in larger quantities that exert and over-riding influence on their growth, moreover, vegetables like radish and turnip, being fast growing, need high doses of applied N together with adequate P and K. Thus with the application of kg ha -1, production of maximum number of healthy mature leaves and dry matter with high K content would be expected. The resultant higher leaf area of treated plants would ensure the production of comparatively more photosynthates for storage organs (root). It may be pointed out that, unlike cereals and other monocots; the requirement of K is more for dicots to which radish and turnip belong. As absorption of K is known to depend considerably on the levels of N, the better supply of N to a crop the greater the increase due to K (Gartner, 199; Healthcote, 197; Wright et al., ). Table 1: Effect of basal doses of nitrogen on leaf and root potassium content in two varieties of radish at three stages of growth (% dry weight) Sampling stages(days after sowing) 35d 5d 5d Varieties Organs (kg N ha -1 ) (kg N ha -1 ) (kg N ha -1 ) 15 Mean 15 Mean 15 Mean Pusa Leaf 1.973 1. 1.8 1.33 1. 1.58 1.79 1.55 1.3 1. 1.5 1.33 Rashmi Root.93 1.33 1.5 1.35 1. 1.3.5 1.3 1.5 1. 1.3 1.7 Local Leaf.39 1. 1.593 1.7.3 1. 1.9.998.3 1. 1. 1.13 Root.8 1.3 1.55 1.18. 3.8 3.8.7.85..8 1.91 Mean Leaf 1.181 1.3 1.3.75 1.39 1..8 1.15 1.575 Root.881 1. 1.533 1.533.58.793 1.175 1..11 C.D. at5% (T) Leaf Root.19..1.3.5.11 (V) Leaf Root.15.8.9 NS.53.9 T V Leaf Root.7.1.17.8.9.1 International Journal of Environmental Sciences Volume No., 11 33
Leaf production (number/plant) 1 8 N (kg/ha) 15 N (kg/ha) 1 N (kg/ha) Snow Ball Local.5*.*.3*.55*.58*.3*.5*.* 5.539* Top fresh weight (g/top) 3.51*.31*.91*.5*.37*.5*.381*.381*.959*.783* 1.357* Root fresh weight (g/root) 8.87* 1.*.18*.55*.875*.5*.37*.*.97*.59* 1.9* 35d 5d 5d Sampling stages Figure 3: Effect of basal doses of N on leaf production, top and root fresh weight in two varieties (Snow Ball and Local) of turnip at four stages of growth Physiologically speaking, K is the most important cation for plants. This applies both to its content in plant tissue as well as to its physiological and biochemical functions. It has be observed that K enhances the translocation of photosynthates (Marschner, 198). Further it has been observed by Schere et al. (198) and Bensichen and Neeteson (198), albeit for other crops that competitive absorption occur between K + and NH + possibly due to completion for a common carrier. It is noteworthy that the source of N in the present study was urea which would ensure unhindered absorption of K from soil. Favorable effect of N on 8d International Journal of Environmental Sciences Volume No., 11 3
the dry matter production and K content has been reported by Lefevre and Lefevre (1957); and Verma et al. (1998) in other crops. N (kg/ha) 15 N (kg/ha) 1 N (kg/ha) Snow Ball Local Top dry weight (g/top) 3 1.9*.*.38*.1*.5*.75*.18*.9*.15* Root dry weight (g/root) 5 3 1.*.7*.*.9*..8*.13*.9*.7*.13*.18*.1*.17* Sampling stages 35d 5d 5d Figure : Effect of basal doses of N on top and root dry weight in two varieties (Snow Ball and Local) of turnip at four stages of growth Regarding varietal differences, Pusa Rashmi variety of radish by and large proved superior to the other variety in leaf production, root dry weight and leaf K content. On the other hand, root K content was higher in local variety (Fig 1 and : Table 1). In turnip, Snow Ball surpassed local variety in all parameters studied (Fig 3 and : Table ).. Millikan, (191) among others, has noted that the varietal differences in the feeding power within species have been found, in certain cases, to be greater than differences between related species or even genera. It may, therefore, be argued that the improved varieties (Pusa Rashmi variety of radish and Snow Ball of turnip) possessed more efficient mechanism for the absorption, translocation and utilization of the applied nutrients including K, by virtue of their superior genetic makeup. Naturally this manifested itself through the observed higher values of these parameters. This is highlighted further by the superior interaction effect between the highest N dose and the improved varieties of the two crops. 8d International Journal of Environmental Sciences Volume No., 11 35
Table : Effect of basal doses of nitrogen on leaf and root potassium content in two varieties of turnip at four stages of growth (% dry weight) Finally while considering the distribution of K in root and shoot of the two crops, it may be noted that generally K content in tops of both crops was higher at 35d compared with that at other stages. This is because nutrients content during early stages of growth increased due to relatively higher nutrient uptake rate compared with growth rate, apparently, K content decreases in leaves and increases in roots as the two crops grow. Munro and Cutcliffe 197; and Taylor et al.,1983 also made similar observations in other comparable crops. The present study thus confirms that translocations of nutrients from root to top is more efficient during the early phase of growth, whereas at later stages, root would provide the sink for the accumulation of nutrients and show higher K content. Generally, a decrease in K concentration was noted in both crops as the plants advanced in age (Table 1 and ) because vigorous increase in volume results in a dramatic reduction in the mineral content of the plant (Munro and Cutcliffe, 197). Acknowledgement The authors are grateful thanks to department of Botany to providing proper necessary facilities related to work. References International Journal of Environmental Sciences Volume No., 11 3
1. Bensichen M L V., and Neeteson J J (198), urea nutrition of young maize and sugerbeet plants with emphasis on ionic balance and vascular transport of nitrogen compounds. Netherlands Journal of Agriculture Science, 3, pp 317-33.. Friden J L., and Vaico J J (), dependence of cotton leaf nitrogen, chlorophyll and reflectance of nitrogen and potassium availability. Journal of Agronomy, 9, pp 3-9. 3. Gartner J A (199), effect of fertilizer nitrogen on dense sand of Kikuyn. Papalum and Carpet grasses interaction with phosphorus and potassium. Queenland Journal of Agriculture and Animal Science,, pp 35-37.. Haeder H E., Mengal K N., and Forster H (1973), the effect of potassium on translocation of potato plants. Journal of Science Food and Agriculture,, pp 179-187. 5. Heathcote R C (197), fertilization with potassium in the Savanna zone of Nigeria. Potash Review Subject, 1, 57 th Suite.. Lefevre G., and Lefevre P (1957), observation on the uptake of nutrients by winter rape. In: Potassium in Agriculture. R D Munson (ed.). American Society of Agronomy, 1985. 7. Love A (1978), the response of potassium dressing related to the nature of the crop, the potassium level of the soil and the magnitude of nitrogen potassium interaction in pot. In: Soil and Crops. G S Sekhon (ed). Potassium Research Institute of India, New Delhi, pp 15-183. 8. Lu Y X., Li C J., and Zhang F S (5), transpiration and potassium uptake and flow in tobacco as affected by nitrogen forms and nutrient levels. Annals of Botany, 95(), pp 991-998. 9. Marschner H (198), mineral nutrition of higher plants. Academic Press, London.. Millikan C R (191), plant varieties and species in relation to the occurrence of deficiencies and excess of certain nutrient elements. Journal of Australian Institute Agriculture Science,, pp -33. 11. Munro D C., and Cutcliffe J A (197), relation of nutrient content of rutabaga leaves to fertilization with N, P and K. Canadian Journal Plant Science, 5, pp 135-139. 1. Panse V G., and Sukhatme P V (197), statistical methods for agricultural workers. nd ed. Indian Council of Agricultural Research, New Delhi. 13. Scherer H W., Mackown C T., and Logget J E (198), potassium-ammonium uptake interaction in tobacco seedlings. Journal of Experimental Botany, 35, pp -7. 1. Taylor O A., Fetuga B L., and Oyenuga V A (1983), accumulation of mineral elements in 5 tropical leafy vegetables as influenced by nitrogen fertilization and age. Journal of Science and Horticulture (AMST), 18, pp 313-3. International Journal of Environmental Sciences Volume No., 11 37
15. Verma R B., Singh P K., and Singh S B (1998), effect of nitrogen and potassium levels on growth, yield and nutrient uptake of colocasia. Journal of Root Crops,, pp 139-15. 1. Wright D., Marois J J., and Snyder C (), influence of tillage system, potassium and nitrogen on hardlock bolls in cotton. International Plant Nutrition Institute (IPNI). 55 Engineering Drive, Suite 1. Norcross, GA 39-831. International Journal of Environmental Sciences Volume No., 11 38