Final SPH -JHS Coverpage 17-1 Jan 2022 single J. Hortl. Sci. Vol. 17(1) : 110-117, 2022 This is an open access article d istributed under the terms of Creative Commons Attribution-NonCommer cial-ShareAl ike 4.0 International License, which permits unrestricted non-commercial use, d istribution, and reproduction in any med ium, provide d the original author and source are credited. Original Research Paper INTRODUCTION Gladiolus (Gladiolus hybrida) is a popular cut f lower c r op a nd innu mer a b le c u lt iva r s wit h attractive colors are available for cultivation. It belongs to the family Iridaceae. However, the area increase under gladiolus cultivation was negligible during the last decade despite huge demand for this flower cr op both at nationa l and internationa l levels. The area under gladiolus cultivation was 11, 660 ha during 2011-12 and increased to 11,850 ha du r ing 2 0 1 7 - 1 8 ( N H B, 2 0 1 8 ) . C ommer c ia l production of gladiolus depends largely on the availa bility of pr opagating mater ia l especially corms. Large size corm helps in better plant growth and development by supplying storage nutrients in the corm. The slow multiplication rate of quality planting material either cor ms or cormels is a r ec ur r ing p r oblem a nd is hinder ing the a r ea ex pa ns ion of t his f lower c r op. D u e to s low multiplication rate, dormancy of corms/cormels and high per c ent a ge of spoila ge of cor ms dur ing storage, there is an insufficient supply of planting material (Memon et al., 2009; Priyakumari and Sheela, 2005; Swapnil et al., 2017). As cormel production in terms of number per plant is more than corm number and the resource use efficiency of cormels as propagating material needs to be assessed either for corm/cormel production or for production of flower spikes in gladiolus to address the problems of short supply of planting material and huge domestic demand. Genotypic variations in biomass production and nutrient removal pattern in gladiolus raised from cormels Sujatha S.*, Rao T.M., Rajiv Kumar and Rupa T.R. ICAR- Indian Institute of Horticultural Research, Hesaraghatta, Bengaluru-560089, India *Corresponding author email: s_sujatha68@rediffmail.com ABSTRACT The present study was conducted at ICAR-IIHR, Bengaluru, India during 2018-2019 to quantify resource use efficiency in 11 genotypes of gladiolus propagated through cormels based on growth, biomass partitioning and nutrient removal pattern. Growth and yield parameters differed significantly among genotypes. The leaf number was significantly higher in Arka Shobha (9.67) and Arka Manorama (9.00) than other genotypes (6.33-8.67). The spike length was higher in Arka Naveen (102.9 cm) and lesser in Arka Kumkum (66.2 cm). The pattern of biomass partitioning indicated that below ground biomass (corm) accounted for 71.5% of total biomass (3990 kg ha-1), while above ground biomass (leaf and spike) was 28.5% of total biomass (1137 kg ha-1). In gladiolus genotypes, the nutrient profile indicated that the accumulation of N was higher in corms followed by leaves and spikes. The accumulation of P (0.13-0.14%), Mn (29.8-43.5 mg kg-1), Zn (15.3-23.4 mg kg-1) and Cu (5.2-6.0 mg kg-1) was similar. Spikes accumulated higher K and Mg than leaves and corms. The accumulation of Ca was more in leaves (2.39%) followed by flower stalks (1.95 %). The average Fe concentration (mg kg-1) was more in corms (293) followed by leaves (269) and flower stalks (160). The average nutrient removal in genotypes was quantified at 122 kg N, 10.8 kg P and 71.7 kg K per ha per crop. The nutrient demand (g ha-1) of Fe was more (1062.4) than Mn (152.5), Zn (23.8) and Cu (23.0). The data implies that gladiolus is a heavy feeder of N and K. Nutrient removal of K and Fe influenced the biomass production with high degree of variability (Y =-541.858 + 24.097 Kuptake + 1.405 Feuptake R 2=0.995). The present study gives scope for precision nutrient use by avoiding blanket recommendations. Keywords: Biomass partitioning, cormels, genotypes, gladiolus and nutrient removal 111 J. Hortl. Sci. Vol. 17(1) : 110-117, 2022 Balanced nutrition is required for getting optimum yields of both spikes and corms/cormels in gladiolus cultivation. Though several reports highlighted the importance of major and micronutrients especially boron and zinc for increased weight and number of corms and cormels per hill in gladiolus, present nutrient recommendations are highly variable (Afify, 1983, Shah et al.,1984; Mukherjee et al., 1998; Singh, 1996 and Das, 1998; Shankar and Dubey, 2005; Singh et al., 2013; Satpathy et al., 2016). No data exist on nutrient requirement of gladiolus varieties based on biomass production and nutrient removal pattern. Soil health is another crucial factor for obtaining higher production of below ground biomass (Baldotto and Baldotto, 2013). Thus, precision farming approach with adequate nutrient supply is essential by assessing the nutrient demand of gladiolus genotypes through biomass and nutrient partitioning, and nutrient removal pattern. With this background, the present study was carried out to precisely assess the demand of various nutrients for different plant components especially corms and cormels in various gladiolus genotypes. MATERIALS AND METHODS Description of study site The present study was carried out in experimental field at ICAR-Indian Institute of Horticultural Research, Hesaraghatta, Bengaluru, Karnataka, India (13o7’N latitude and 77o 29’E longitude, 890 m above MSL). The climate of the experimental site is semi-arid. The soil of the experimental site is red sandy loam. Experimental details The study was carried out in the ongoing breeding experiment comprising of identified genotypes and advanced breeding lines at ICAR-IIHR during 2018- 2019. Uniform cormels of different genotypes were planted in fourth week of January, 2018 at a spacing of 30 cm x 20 cm on raised soil beds. Recommended plant protection measures were followed for control of major pests and diseases. Nutrients were applied @ 200:200:200 kg NPK ha-1 in two splits in addition to application 10 t of FYM per hectare before planting. The trait specific genotypes identified at ICAR-IIHR were used to find out overall picture of resource use in gladiolus raised from cormels as propagating material. About eleven IIHR identified genotypes were selected and were evaluated in randomized block design (RBD) with three replications. The desirable traits of genotypes are given in Table S1. Growth parameters and biomass estimation Growth observations such as plant height, leaf number, tiller number and spike length were recorded in three plants in each replication of all genotypes. For estimation of both above ground and below ground biomass, destructive sampling method was adopted. Three plants from each genotype were collected in 2018 just before initiation of flowering and at harvestable stage of spikes. Fresh weight was recorded sepa ra tely for leaves a nd spikes/flower stems. Similarly, the fresh biomass of corm/cormels was estimated by collecting all corms/cormels from each plant separately. Samples were cleaned with distilled water, air dried, packed in brown paper bags, oven dried at 600C to a constant weight and dry weight was recorded after drying. After recording oven dry weight, same samples were ground and kept in labeled butter paper bags for nutrient analysis to find out nutrient accumulation and removal pattern. The average biomass of each part was multiplied with total number of leaves and flower stems/spikes to arrive at total above ground biomass. The below ground biomass was also estimated in a similar manner by multiplying corm/cormel number per plant with biomass per plant. The biomass of leaf, flower stem and corms/cormels was considered to arrive at total biomass production. Collection and analysis of soil and plant samples Soil samples were collected at 0-25 cm depth in the root zone at 15 cm distance from the base after harvesting of corms. The air-dried soil samples were ground to pass through a 2.0-mm sieve and kept in labelled plastic bags for further analysis. Soil chemical/fertility parameters like pH, organic carbon, available P and K were analysed for using standard procedures (Jackson 1973). Soil organic carbon was measured by titration method (Walkley and Black, 1934). Soil test P was estimated by ascorbic acid reductant method (Watanabe and Olsen 1965) for colour development after extraction with Olsen’s reagent. Available K, Ca and Mg were estimated in Flame Photometer using ammonium acetate extract. The concentration of micronutrients was estimated in AAS using diethylene triamine penta acetic acid (DTPA) extract (Lindsay and Novell 1978). T he lea f, flower stem and corm samples wer e a na lysed sepa r a tely for t ota l N using mic r o- Kjeldahl digestion method (Jackson 1973). The Biomass production and nutrient removal pattern 112 Sujatha et al J. Hortl. Sci. Vol. 17(1) : 110-117, 2022 Variety Plant Flower No. Above ground biomass (g plant-1) Below ground biomass (g plant-1) height stem of (cm) length leaves Leaf Flower Total Corm Cormel* Total Root (cm) stalk Arka Aarti 79.3 74.8 6.33 4.40 2.97 10.30 13.4 10.9(14) 14.3 0.07 Arka Aayush 77.7 73.5 8.33 3.60 5.30 10.20 16.7 10.4(17) 17.4 0.30 Arka Amar 94.3 88.9 8.67 5.70 5.17 17.90 22.2 3.6(10) 24.6 0.33 Arka Darshan 77.0 73.1 6.33 3.73 5.70 12.17 18.3 10.3(19) 19.7 0.40 Arka Gold 94.7 89.6 6.67 4.90 3.50 18.40 29.1 3.4(8) 33.6 0.07 Arka Kumkum 70.5 66.2 7.50 1.83 5.07 9.27 14.3 7.4(11) 15.5 0.37 Arka Manorama 85.3 80.7 9.00 2.53 5.37 11.10 15.6 2.4(7) 17.5 0.07 Arka Naveen 107.7 102.9 8.33 5.40 6.03 13.07 27.2 5.5(8) 27.9 0.40 Arka Poonam 104.3 99.5 8.33 3.23 7.20 15.67 25.9 3.6 (8) 28.9 0.27 Arka Shobha 94.7 89.9 9.67 6.53 3.87 21.00 31.9 3.0(7) 36.4 0.20 Arka Tilak 80.3 75.5 8.33 4.33 7.83 14.87 24.2 4.6(5) 25.8 0.13 Mean 87.8 83.2 7.95 4.20 5.27 13.99 21.73 2.06 23.8 0.236 CD (p=0.05) 15.32 14.11 NS 0.880 0.923 2.438 4.03 0.863 4.68 0.085 *Figures in the parenthesis indicate cormel number Table 1. Growth and biomass partitioning in gladiolus genotypes propagated from cormels plant samples were digested using 1:3 perchloric- nitric acid mixture for estimation of total P, K and micronutrients in different plant parts of flower stalk. Total P (vanadomolybdate) was determined following Piper (1966). Estimation of total K, Ca, M g wa s do ne in f la me p hot o met er a nd micronutrients like copper (Cu), zinc (Zn), iron (Fe) and manganese (Mn) was done in AAS. Nutrient removal was computed by multiplying nutrient concentration in each plant part with respective oven-dry biomass and presented per hectare basis. Statistical Analysis All data were analyzed using SPSS and Microsoft Excel. The significant differences between the two means are indicated by LSD (5%) values in the tables. Correlations and regressions among different biomass parameters and nutrients were worked out for better understanding of results. Differences among genotypes were tested with ANOVA and LSD. RESULTS AND DISCUSSION Growth parameters in different genotypes The growth parameters such as plant height, leaf number and spike length differed significantly among genotypes. The plant height of genotypes varied from 70.5 cm in Arka Kumkum to 107.7 cm in Arka Na veen. T he flower stem length a lso differ ed significantly among genotypes. The flower stem length was higher in Arka Naveen (102.9 cm) and lesser in Arka Kumkum (66.2 cm). The leaf number was significantly higher in Arka Shobha (9.67) and Arka Manorama (9.00) than other genotypes with medium leaf number (7.50-8.67) and genotypes with less leaf number (6.33-6.67). The corm number was similar in a ll genotypes (2), but the cor m weight va r ied significantly due to different size corms. Cormel number and weight were significant among genotypes. The average dry weights of all components per plant varied significantly among genotypes and were used for computing total biomass production per hectare (Table 1). Biomass partitioning to different components With respect to biomass production in different genotypes raised from cormels (Fig. 1), the biomass par titioning to spikes (15.9%) was mor e tha n pa r titioning to lea ves (12. 6%) except in four genotypes (Arka Amar, Arka Aarathi, Arka Shobha and Arka Gold). The partitioning of total biomass (3990 kg ha-1) was maximum to below ground corm biomass (71.5%). In gladiolus genotypes raised from corms, the partitioning to corms is only 46% of the total biomass (Sujatha et al., 2020c). The average partitioning of biomass to both leaves and 113 J. Hortl. Sci. Vol. 17(1) : 110-117, 2022 Biomass production and nutrient removal pattern spikes was 1137 kg ha -1 (28.5% of total). Leaf biomass was significantly higher in Arka Shobha (784 kg ha-1), while spike biomass production was significantly higher in Arka Tilak (940 kg ha-1). The biomass of corms was higher in Arka Shobha (4366 kg ha-1). It is clear that higher biomass partitioning to spikes resulted in r educed cor m biomass in genotypes, while higher biomass partitioning to lea ves is r equ ir ed f o r higher c or m b ioma s s production. For planting material multiplication, this aspect needs to be considered. The availability of recyclable biomass as leaf and spikes was 28.5% of t ot a l b i oma s s in c a s e of r ec y c ling a f t er utilization. Nutrient accumulation in different plant components T her e wer e s ignifica nt va r ia tions in nut r ient accumulation of major and secondary nutrients in all plant parts such as leaves, spikes and corms Fig. 1. Biomass partitioning in different genotypes of gladiolus with cormels as planting material (CD (p=0.05) for leaf biomass: 112.8; flower stalk biomass: 118.3; aboveground biomass: 139.2; Below ground biomass: 601.1) a mong genotypes (Fig. 2 and 3). In gla diolus genotypes, the nutrient profile among different plant p a r t s a ls o s howed dis t inc t p a t t er n. T he accumulation of N was higher in corms followed by lea ves a nd spikes in a ll genotypes. T he P accumulation was similar in all plant parts (0.13- 0.14%). Spikes accumulated higher K than leaves and corms. The accumulation of Ca was more in leaves (2.39%) followed by spikes (1.95 %) and corms (0.39%). The Mg accumulation was higher in f lower st a lks ( 0. 38% ) followed b y lea ves (0.34%) and corms (0.16%) more Ca and Mg than cor ms. Among micr onutr ients, the a vera ge Fe concentration (mg kg-1) was more in corms (293) followed by leaves (269) and flower stalks (160). The range in concentrations (mg kg-1) of Mn, Zn and Cu were 29.8-43.5, 15.3-23.4 and 5.2-6.0, respectively. The previous reports indicated that genotype variability in nutrient content and nutrient uptake is crucial for genetic improvement (Dierig et al., 2003 Feil et al., 2005 Brink et al., 2001). 114 Sujatha et al J. Hortl. Sci. Vol. 17(1) : 110-117, 2022 Fig. 2. Nutrient accumulation pattern in gladiolus genotypes raised from cormels CD (p=0.05) for nutrients in leaf (N: 0.172; P: 0.005; K: 0.192;Ca:0.188 Mg: NS), flower stalk (N: 0.147; P: 0.019; K: 0.237;Ca:0.194 Mg:0.06) and corms (N: 0.237; P: 0.008; K: 0.041;Ca: NS Mg: NS) Fig. 3. Micronutrient accumulation pattern in gladiolus genotypes raised from cormels CD (p=0.05) for nutrients in leaf (Fe:38.8, Mn: 6.9, Zn: NS, Cu; NS), flower stalk (Fe:29.9, Mn: NS, Zn:NS, Cu: NS) and corms (Fe:49.5, Mn:5.1, Zn: NS, Cu: NS) Biomass production and nutrient removal pattern Nutrient uptake pattern The uptake of major, secondary and micro nutrients differed significantly among different genotypes of gladiolus (Fig. 4). The total N removal ranged from 87 kg ha-1 in Arka Aarti to 178 kg ha-1 in Arka Shobha. The removal of P and K ranged between 6.1-15.2 kg ha-1 and 46.4-103.2 kg ha-1. The average nutrient removal per hectare per year in genotypes raised from cormels was quantified at 122 kg N, 10.8 kg P and 71.7 kg K. The nutrient removal for secondary nutrients ranged between 24.7-43.4 kg for Ca and 6.2- 10.8 kg for Mg. Among micronutrients, the demand in terms of grams per hectare for Fe was more (1062.4 g ha-1) than Mn (152.5), Zn (23.8) and Cu (23.0). The order of nutrient uptake in gladiolus in all genotypes was N>K>Ca>P>Mg>Fe>Mn>Zn>Cu. The data implies that gladiolus is a heavy feeder of N and K. In comparison to gladiolus raised from corms (Sujatha et al., 2020c), the biomass production and nutrient uptake by gladiolus genotypes raised from cormels are considerably lower. Higher corm biomass production with less nutrient uptake in gladiolus genotypes raised from cormels gives scope for largescale planting material multiplication utilizing cormels. 115 J. Hortl. Sci. Vol. 17(1) : 110-117, 2022 In gladiolus genotypes, the correlations (Table 2) were highly significant for total biomass production and removal of N (r=0.938), K (r=0.968), Ca (r=0.967) and Mg (r=0.941) and P removal did not influence significantly total biomass production (r =0.292). Application of stepwise regression technique to identify the nutrient variables with a significa nt influence on the total bioma ss (Y) r esulted in the following equa tion, wher e the variables are written in the increasing order of p- level. Multiple r egression ana lysis of r emoval/ uptake of nutrients with total biomass production showed high degree of relation and nutrient removal of K and Fe influenced the biomass production with high degree of variability. Y (total biomass) = -541.858 + 24.097 Kuptake + 1.405 Feuptake (R 2=0.995) Soil fertility status T he s oil f er t ilit y s t a t u s a t t he end of experimentation was above optimum with soil pH near to neutral (7.07) and the soil organic carbon was 1.32%. The availability of soil nutrients was quantified at 22.3 ppm of P, 335 ppm of K, 4799 ppm of Ca, 1208 ppm of Mg, 11.3 ppm of Fe, 8.5 ppm of Mn, 5.6 ppm of Zn and 4.1 ppm of Cu. T he soil fer tility sta tus implies tha t gla diolus system maintains optimum soil fertility despite higher biomass r emoval in the for m of corms/ cormels and the nutrient application can be adjusted based on nutrient uptake pattern to save critical inputs. CONCLUSIONS The present study assessed the pattern of biomass and nutrient partitioning, and nutrient demand of different genotypes in gladiolus when cormels were used as planting material. The major influence of N, K, Ca and Fe on biomass production in gladiolus was evident in this study. The results of the present study can be used as basis for assessing the nutrient r equir ement of gla diolus when r aised thr ough Fig. 4. Nutrient removal pattern in gladiolus genotypes raised from cormels Above Below Total Leaf Spike ground ground N P K Ca Mg Fe Mn Zn Parameter biomass biomass biomass biomass biomass uptake uptake uptake uptake uptake uptake uptake uptake Leaf biomass 0.71** Spike biomass 0.15 -0.27 Above ground biomass 0.71** 0.58* 0.63** Below ground biomass 0.99** 0.69** 0.04 0.59* N uptake 0.94** 0.59* 0.04 0.51* 0.96** P uptake 0.29 -0.14 0.98** 0.72** 0.10 0.17 K uptake 0.97** 0.68** 0.16 0.69** 0.95** 0.89** 0.31 Ca uptake 0.97** 0.71** 0.26 0.80** 0.93** 0.89** 0.39 0.94** Mg uptake 0.94** 0.52* 0.41 0.77** 0.90** 0.88** 0.52* 0.91** 0.96** Fe uptake 0.94** 0.67** 0.08 0.61** 0.94** 0.92** 0.18 0.83** 0.88** 0.87** Mn uptake 0.97** 0.81** 0.01 0.67** 0.96** 0.92** 0.17 0.95** 0.93** 0.84** 0.90** Zn uptake 0.62** 0.47* 0.61* 0.89** 0.50* 0.43* 0.70** 0.59* 0.69** 0.66* 0.54* 0.59* Cu uptake 0.93** 0.68** 0.19 0.71** 0.91** 0.89** 0.32 0.86** 0.88** 0.84** 0.94** 0.93** 0.66* Table 2. Correlation matrix for biomass and nutrient uptake 116 Sujatha et al J. Hortl. Sci. Vol. 17(1) : 110-117, 2022 cor mels. T he r esults give scope for pr ecision nutrient application that would reduce the cost of production and avoid soil fertility buildup due to excess nutrient application. ACKNOWLEDGEMENTS The authors sincerely acknowledge the Director, ICAR-IIHR for timely help and encouragement in carrying out the present study. REFERENCES Afify, M. M. 1983. Effect of high fertilizer rates on t he gr owt h a nd f lower ing of t hr ee gla diolus cultiva r s. Ker leszef i Egya tem Kkozlemenyel 47(13): 75-85 Ba ldott o, M. A. a nd Ba ldot to, L. E . B. 2 01 3. Gladiolus development in response to bulb treatment with different concentrations of humic acids. Revista Ceres 60:138-142. Bastug, R., Karaguzel, O. Aydinsakir, K. and Buyukta s, D. 2006. T he effects of dr ip irrigation on flowering and flower quality of glasshouse gladiolus pla nt. Agric. Water Manage. 81:132–144. Brink, G.E., G .A. Pederson, K. R. Sistani, and T. E. Fairbrother. 2001. Uptake of selected nutrients by temperate grasses and legumes. Agronomy Journal 93, 887–890 Chanda, S. Barma, G. and Roychowdhury, N. 2000 . Influence of different level of nitrogen, phosphorus and potassium on growth and flowering of gladiolus. The Horti. J. 13(1): 76-86. Das, A., Baiswar, P., Patel, D.P., Munda, G.C., G hos h, P. K . a nd C ha ndr a , S . 2 0 1 0 . Productivity, nutrient harvest index, nutrient balance sheet and economics of lowland rice (Oryza sativa) as influenced by composts made from locally available plant biomass. Inbd. J. Agric. Sci. 80(8), 686-690. Das, T. K. 1998. Corm and cormel production in gladiolus as affected by spike removal and K application. Indian J. Hort. 55(4): 327-331 Feil, B., S. B. Moser, S. Jampatong, and P. Stamp. 2005. Mineral composition of the grain of tropical maize varieties as affected by pre- a nt hes is d r ou ght a nd r a t e of nit r ogen fertilization. Crop Science 45, 516–523. Gupta, P, Neeraj, R. and Dheeraj, R. 2008. Effect of different levels of vermicompost, NPK and FYM on performance of gladiolus (Gladiolus grandiflorus L.) cv. Happy End. Asian J. Hort. 3:142-143. Ja ckson, M. L. 1973. Soil Chemica l Analysis. Prentice Hall of India Pvt. Ltd., New Delhi. Lindsay, W. L., Norvell W. A., 1978. Development of DTPA test for zinc, iron, manganese and copper. Soil Sci. Soc. Am. J. 42, 421–428. Memon, N. Qasim , M., Jaskani , M. J., Rashid Ahma d a n d I f t ikha r Ahma d ( 2 0 0 9 ) Enhancement of corm and cormel production in gladiolus (Gladiolus spp.), New Zealand Journal of Crop and Horticultural Science, 37(4): 319-325. Mukherjee, S., Jona, S. C. and Chatterjee, T. K. 1998. Effect of nitrogen and phosphorus dose on production of flowers and corms of gladiolus. Indian Agriculturist 36(3): 211-213 NHB. 2018. Ar ea and pr oduction statistics of horticultural crops. National Horticulture Board. New Delhi. Piper, C.S. 1966. Soil and Plant Analysis. Hans Publishers, Bombay. Pr iya kuma r i, I. a nd Sheela , V. L. 2005. Micropropagation of gladiolus cv. ‘Peach blossom’ through enhanced released of axillary buds. Journal of Tropical Agriculture 43: 47– 50 Satapathy, S.P., Toppo, R., Dishri, M., and Mohanty, C. R. 2016. Impact of integrated nutrient management (INM) on flowering and corm production in gladiolus. Biometrics Biostatistics Int. J. 4(7): 1-19. Shah, A., S. D. Lal and Seth, J. N. 1984. Effect of different levels of nitrogen and phosphorus on growth,flowering and corm yield of gladiolus cv. Vinks Glory. Progressive Horticulture. 16(3/ 4): 305-307 Shankar deo and Dubey, P. 2005. Effect of NPK, FYM and NPK+FYM on growth, flowering and corm yield of Gladiolus when propagated 117 J. Hortl. Sci. Vol. 17(1) : 110-117, 2022 Biomass production and nutrient removal pattern through cormels. J. Soils and Crops 15(1)-34- 38. Singh Rahul, Mukesh Kumar, Sameeksha Raj and Sanjay Kumar. 2013. Effect of integrated nutrient management (INM) on growth and flowering in Gladiolus (Gladiolus grandiflorus L. ) cv. “ White Pr osper ity” Annals of Horticulture 6(2): 242-251. Singh, K. P. 1996. Studies on size of cormel and levels of nitrogen on corm multiplication in gladiolus. Adv. Plant Sciences 9(2): 241-243 Singh, W., Sehrawat, S. K., Dahiya, D. S. and Singh, K. 2002. Leaf nutrient status of gladiolus (Gladiolus grandiflorus L.) cv. Sylvia as affected by NPK application. Haryana J. Hort. Sci. 31(1-2): 49-51. Sujatha S., T. Manjunatha Rao, Rajiv Kumar and T. R. Rupa. 2020c. Resource use indicators and carbon stocks in different genotypes and species of gladiolus for precision farming. J. Plant Nutrition 43 (17): 2645-2663 doi.org/10.1080/ 01904167.2020.1793184 Swapnil Bharti, Urfi Fatmi and Devi Singh. 2017. Suitability of cut corms as planting material on flowering, corm and cormel production in G la diolu s ( G l ad i o l u s g r a nd i f l o ru s L . ) Varieties. Int. J. Curr. Microbiol. App. Sci. 6(8): 2935-2939. Walkley, A., Black, I. A., 1934. An examination of degtjareff method for determining soil organic matter and a proposed modification of the chromic acid titration method. Soil Science 37:29-37. Watanabe, F.S. and Olsen, S. R. 1965. Test of a scor bic a cid method for deter mining phosphorus in water and sodium bicarbonate extracts of soil. Soil Sci. Soc. Am. Proc. 29: 677-678. (Received: 06.01.2020; Revised: 18.04.2022; Accepted: 22.06.2022) 14 Sujatha S.pdf