Estimation of Nutrient Uptake and Available Nutrient Status of Rabi Safflower Through Soil Test Crop Response in Rainfed Ecosystem

Carthamus tinctorius Linn placed in Compositae or Asteraceae family and originated from Abyssinia and Afganisthan. It is locally known as Kardai, Kusumbha and Kusum. Safflower is mainly grown for the edible oil (24-36%) by Chhidda Singh et al., (2020). Since it is dying oil, it has industrial uses in the manufacture of paints, varnishes, soap making, waterproofing material and plastic adhesives for glass. Chhidda Singh et al., (2020) observed that the oil cake from decorticated seed is fed to cattle and it contains 40-50% protein. The oil contains more polyunsaturated fatty acids like lineolic and linolic and it is good for heart patient as it maintains low level of blood cholesterol. As the natural color is obtained from carthamine pigment and the petals having medicinal value, cure rheumatism. The ray and disc florets can be used as the substitute for saffron.The roasted seeds can be eaten or seeds are very relishable food to pigeons. The hull or seed coat used for the preparation of hard board, fuel or decoration. It acts as guard crop as it protects main crop against stray cattle. Safflower oilseed cake contains 5% N, 1.44% P₂O₅, 1.23 K₂O%  which is used as source of organic manure Chhidda Singh et al., (2020).
       
Triptesh et al., (2016) observed that SSNM is one of the scientific approaches to supply the nutrients that match field specific or site specific nutrient requirement of crop. Recommendation with blanket application of nutrients or fertilizers promoted over application of fertilizers in some area of field and under application of fertilizer in other area of field which leads to imbalanced application of nutrient management. SSNM is an best alternative to blanket fertilizer applications recommendation. Site Specific nutrient management is utilizing various tools modern Agriculture technology such remote sensing, geographic information system, global positioning system, variable rate technology, etc  to optimize the supply of essential nutrient over space and time to meet nutrient requirement of crop through 4R’s of nutrient management i.e right product, right rate, right time, right place. SSNM help to increase productivity by enhancing or fertilizer or nutrient use efficiency and profitability by reducing excess cost on fertilizer. It mitigates release of green house gases from agriculture due to excess nitrogen application for crop production.

A research experiment was carried out during rabi 2017-18, 2018-19 and 2019-20 at research farm of agronomy, Dr. P.D.K.V, Akola (Maharashtra). Experiment was conducted on medium deep black soil. Initial  nutrient status of soil indicted 194.0 kg ha^-1 of available nitrogen 26.10 kg ha^-1 of available phosphorus  and slightly high in 327.00 kg ha^-1 of available potassium. Chemical analysis soil indicated that pH=8.0, electrical conductivity=0.30 dSm^-1 and Organic carbon=0.59. Fertilizers were applied based on uptake pattern of crop, target yield levels and soil test values. The experiment was laid out in FRBD-factorial randomized block design with two factors. Total 15 treatment combinations were formed which replication 4 times. Treatments were applied to safflower crop as shown in Table 1.
 

       
The AKS-207 variety of safflower was sown on 6^th Oct 2017, 24^th Sept 2018 and 27^th Sept 2019, respectively. Safflower seeds were dibbled at 45 cm × 20 cm spacing. Gross plot size of research experiment 5.4 m × 4 m and 4.5 m × 3.6 m net executed during the experimental years. Farm yard manure @ 5 t ha^-1 and green gram residue (wet basis) @ 2 t ha^-1 were incorporated to the field before the sowing of safflower. Nutrient were added to the soil through diffrent sources as per the treatments shown in Table 2. Total rainfall during sowing to harvest of safflower were 66.10 mm in 06 rainy days, 175.3 mm in 06 rainy days and 193.1 mm in 14 rainy days during was 2017-18, 2018-19 and 2019-20, respectively. FYM contains 0.46 % N, 0.17% P₂O₅, 0.48% K₂O and green gram residue contains 1.61% N, 0.22 % P₂O₅, 0.55% K₂O.
 

 
Soil test crop response equation
 
STCR equation of safflower crop for targeted yield used for present study has been developed by JNKV-Jawaharlal Nehru Krishi Vidyapeeth, Jabalpur. Considering the similar type of geography, soil type and climatic condition of Jabalpur, the said equation has been used at Akola for conducting experiment with safflower crop.
 
Soil test crop response equation
 
Where:

Nutrient uptake (kg ha^-1) by safflower
 
Effect of different organic sources
 
The data in Table 3 indicate that significantly higher uptake of nitrogen (62.76, 74.67 and 81.89 kg ha^-1), phosphorus (19.15, 24.32 and 29.38 kg ha^-1), potassium (80.32, 92.14 and 99.18 kg ha^-1), sulphur (18.46, 24.10 and 26.09 kg ha^-1) and zinc uptake (493.97, 571.01 and 620.91 g ha^-1) recorded by application of FYM @5 t ha^-1 (M₁) to soil in safflower, being comparable with treatment where green gram residue buried in soil (M₂), during all the year of experimentation. Except nitrogen uptake during 2019-20 and zinc uptake during 2018-19, 2019-20 and significantly superior over no application of manure treatment during first, second and third year of study. The higher nutrient uptake by crop might be due to improvement in soil health through application of organic manure. The results are also corroborated the findings of Datta and Mondal (2006); Rana and Badiyala (2014); Padmavathi et al., (2016) and Krithika et al., (2024).
 
 

 
Effect of nutrient management treatments
 
The  data in Table 3 indicated that the highest total uptake of nitrogen (66.89, 78.99 and 90.06 kg ha^-1), phosphorus (20.78, 25.31 and 31.96 kg ha^-1), potassium (86.05, 97.99,109.09 kg ha^-1), sulphur (20.27, 26.39 and 29.80 kg ha^-1) and zinc (537.78, 618.06 and 696.21 g ha^-1) were obtained with application of fertilizer through STCR with Zinc Sulphate @ 25 kg ha^-1 and Sulphur @ 10 kg ha^-1 (F₃), which was significantly superior over rest of nutrient management treatments and was found at par with treatment of STCR (F₂), respectively. 
       
This might be due to the fact that efficient utilization specific nutrients by the healthy and vigorous plants at various vegetative and reproductive growths which were increases nutrient uptake by plant. These results are in consonance with Majumder et al., (2017) and Krithika et al., (2024).
 
Available N, P, K, S, Zn status in soil
 
Effect different organic sources
 
Data on available nitrogen, phosphorus, potassium, Sulphur and Zinc in soil as influenced by different treatments during 2017-18, 2018-19 and 2019-20 are presented in Table 4 The results revealed that the highest available nitrogen (210.95, 217.41 and 222.18 kg ha^-1), phosphorus (27.81, 29.38 and 31.58 kg ha^-1), potassium (336.75, 338.06 and 342.03 kg ha^-1) and sulphur (8.73, 9.28 and 10.00 mg kg^-1), respectively in soil was registered with application of 5 t farm yard manure ha^-1 (M₁) and superior than other manure application treatments during 3 years of experimentation. There was no significant change in concern with available zinc (mg kg^-1) in soil after harvest of safflower during all year of experimentation. FYM application increased the soil organic matter content in soil. Further, they have reported that organic manure had greater residual effect on long term basis. The results are in close agreement with the findings by Rana and Badiyala (2014).
 
Effect of nutrient management
 
Data on available nitrogen, phosphorus, potassium, sulphur and zinc in soil as influenced by different treatments during 2017-18, 2018-19 and 2019-20 are presented in Table 4. During 2017-18, 2018-19 and 2019-20, the status of available nitrogen (216.13, 221.95 and 228.33 kg ha^-1), phosphorus (30.10, 33.13 and 34.00 kg ha^-1), potassium (340.67, 343.33 and 346.06 kg ha^-1) and sulphur (9.27, 9.46 and 10.15 mg kg^-1) in soil significantly improved with the application of STCR with ZnSo₄ @ 25 kg ha^-1 and S @ 10 kg ha^-1) (F₃) as compared to rest of other nutrient management treatments, respectively. There was no significant change in respect to available zinc (mg kg^-1) in soil after harvest of safflower during the three year of experiment.
 

       
Baskar et al., (2017) noticed that balanced application of inorganic fertilizers with organic manure at the time of sowing help to increase growth attributes and yield attributes which reflected in yield of crop. Increased in available NPK with FYM application was also reported by Arbad et al., (2012), Subehia and Sepehya, (2012) and Basavaraja et al., (2019) Abishek et al., (2024).

Form the nutrient transformation data of three years of experimentation it can be concluded that supply of farm yard manure @ 5 t ha-1 is the best practice that con be adopted for safflower crop in respect of nutrient uptake of major and micronutrient, available soil nutrient status and seed yield of safflower. Similarly, for nutrient management point of view, the treatment adopted Site Specific Nutrient Management or Soil Test Crop Response equation+Zinc sulphate @ 25 kg ha^-1+Sulphur @ 10 kg ha^-1 noticed higher uptake of nitrogen, phosphorus, potassium, sulphur and zinc with beneficial impact on yield of safflower and increased available nutrient soil status. Hence it is suggested that for getting optimum safflower productivity, maximum nutrient use efficiency and environmentally sustainable, balanced amount of fertilizers and integrated nutrient management with organic manures should be adopted.

The authors duly acknowledge the Department of Agronomy, Dr. P.D.K.V, Akola for providing necessary facilities and guidance during experimentation.

All authors declare that they have no conflicts of interest.