Effect of fertilizer level and growth regulator on the growth and yield of safflower (Carthamus tinctorius L.) in Prayagraj District.

Introduction

Safflower (Carthamus tinctorius L.) belongs to the family Asteraceae family. The cultivated species, Carthamus tinctorius L, has a chromosomal number of 2n = 24. Safflower is native to semi-arid Mediterranean. It is an annual herb with prickly leaves and bracts that mimic thistles. Additionally, it contains a number of branches, each of which terminates in a spherical flower head that may be yellow, orange, or red. Safflower is a crop that may be grown in a variety of climates and soil types. Based on available data, safflower is cultivated at elevations below 900 meters above sea level. Temperature significantly affects the rate of germination, which occurs three to eight days after sowing. Charles Mazereku.et al. (2014) [2] Its flowers and seeds are processed to vegetable oil, food coloring, flavoring agent, and textile dye. When compared to soybean, sunflower, cottonseed, corn, rapeseed, and palm oil, safflower seeds are the most commonly used (Weiss, 2002; Ogut et al, 2012) [3] . It's oil is rich in saturated and unsaturated fatty acids, including oleic and linoleic acids, as well as a class of flavonoids and phenolic compounds known as antioxidants (Al-Doori, 2025) [4] . Safflower with a high seed oil content (35-40%) of excellent quality has been widely used in the food sector as well as industrial use in biofuel pro-duction and the manufacture of paints (Rahman Kılıç et al, 2024) and varnishes the residue left over after oil extraction includes up to 25% crude protein, it can also be used as animal feed. Nutrient deficiencies, unavailability, or toxicity have been shown to cause unusual plant growth and dramatically reduce crop plant yields globally, the interactions between nutrients in plants have a major impact on the yield of annual crops. The antagonistic or synergistic effects of these interactions may affect the efficiency of nutrient use. (Kursat Korkmaz.et al, 2024) [7] . One of the key tactics for enhancing plant growth and raising crop plant production and quality in agricultural Settings seems to be appropriate and balanced fertilization.

The introduction of plant growth regulators (PGR) has added a new dimension to the possibility of improving the growth and yield of crop. Foliar applications of plant growth regulators, both natural and synthetic, have known to positively influence and improve crop growth and achieving higher yield. Humic acid's availability of nutrients encourages plant growth and productivity regardless of any chemical or physical constraints in the soil. Unlike ground fertilization, which takes longer for seeds to fill, humic acid foliar spray accelerates the buildup of dry matter in plants. (Malan, 2015; Keshavarz et al, 2016) [5,6] Research on many plants has demonstrated that Humic Acid improves their growth both directly and indirectly, with different plant kinds experiencing varied benefits (Hemati et al. 2022) [9] . By enhancing soil characteristics such soil compaction, waterholding capacity, soil microbial activity, and micro/macro element availability, Humic Acid indirectly promotes plant growth. Additionally, it directly enhances plant growth by boosting plant biomass in terms of Humic Acid material absorption and transportation to plant tissues (Amoozad & Zahedi, 2024) [8] . In field crops, GA3 is also said to enhance the efficient portioning and translocation of photosynthates from source to sink (Senthil et al, 2003) (Haifaa et al, 2022) [10,11] conducted a study on the production of rice seeds and found that applying GA3 increased plant height, encouraged panicle and spikelet exertion, improved stigma exertion and longevity, and increased seed set rate and grain yield in rice-a crucial aspect of rice cultivation. They stated that a higher concentration of gibberellins promotes plant growth by promoting cell elongation and a rise in intermodal length in the stem, leaves, and other aerial parts. It revealed that gibberellic acid is a phytohormone that is required in small amounts at low concentrations to improve plant growth and development in order to boost dry weight and yield in safflower (Mahmood and Muhammad. 2022) [12] . Gibberellic acid is one of the growth regulators that helps plants by increasing dry weight, plant production, and vegetative development. (Burhan Arslan and Emrullah Culpan, 2017) [13] seaweed contains a variety of substances that stimulate plant growth, including macronutrient and microelement nutrients, growth hormones, amino acids, vitamins, betaines, cytokinins, and sterols, it can be added as a bio-stimulant to improve plant growth and as an amendment to increase crop yield. (Vafa & Sohrabi et al, 2021) [14] . Seaweed extracts increase plant growth and nutrient uptake by altering physiological and biochemical processes. They raise agricultural output, promote early seed germination, boost root growth, boost leaf chlorophyll, and strengthen tolerance to biotic and abiotic stress. Furthermore, seaweed extracts enhance the soil's biological, chemical, and physical characteristics. This experiment aimed to study the impacts of fertilizer and of biostimulants, (seaweed sap, GA3, humic acid) on the vegetative growth and seed yield of safflower.

Material and Methods: Experimental Site

The experiment was conducted at research farm of Department of Agronomy at Prof. Rajendra Singh (Rajju Bhaiyya) University Naini, Prayagraj. The experiment site falls in a subtropical climate situated at 25°13'28" N latitude and 81°46'25" E longitude and 98 m above mean sea level. Climatic condition Agro-climatically, Prayagraj District represents the subtropical belt of the South East of Uttar Pradesh, and is endowed with extremely hot summer and fairly cold winter. The maximum temperature of the location ranges between 460C -480C and seldom falls below 40C-50C. The relative humidity ranges between 20-94%. The average rainfall of this area is around 1100 mm annually.

Treatment Combination

The experiment is to be done in a randomized block design (RBD) which composed of 10 treatments in 3 replications. The data for growth and yield attributes of Indian Safflower was recorded using five random chosen plants from each treatment after seed sowing. Treatments comprised of T1-RDF @ 50% + GA3 100 ppm, T2-RDF @ 50% + Seaweed Sap 200 ppm, T3-RDF @ 50% + Humic Acid 150 ppm, T4-RDF @ 75% + GA3 100 ppm, T5-RDF @ 75% + Seaweed Sap 200 ppm, T6-RDF @ 75% + Humic Acid 150 ppm, T7-RDF @ 100% + GA3 100 ppm, T8-RDF @ 100% + Seaweed Sap 200 ppm, T9-RDF @ 100% + Humic Acid 150 ppm, T10-Control (Farmer Practices). Two foliar sprays of humic acid, GA3 and seaweed sap were given at 30 DAS and 60 DAS.

Result and Discussion: Growth parameter:

Plant height: Results demonstrated that, across a range of treatment combinations, the application of T9 100% RDF +humic acid 150m ppm showed significantly heighest in plant height, followed by T8 100%RDF + Seaweed sap 200 ppm when compared to T10(control). Thakur et al, (2013) reported that Combined application of RDF + humic acid granules @ 12.5 kg ha-1(as basal) significantly influenced the growth parameters. of branches under all the treatment combination in compare to T10. Hivare et al, 2019 [17] also represent that the treatment combination of humic acid + NAA shows the highest no. of branches. The highest no. of seeds per capitula was obtained in the treatment T9 (100%RDF + 150 ppm humic acid) followed by treatment T8 (100%RDF+ seaweed sap 200ppm) when compared with T10 control. Metre.2013 [19] also shows that the application of humic acid at 100ppm 200ppm results the increase in the no. of seeds per pod.

Test weight: 1000 seed weight was significantly maximum in treatment T9 (100%RDF +150 ppm humic acid) followed by treatments T8 (100%RDF + 200 seaweed sap), when compared with T10 (control).deotel et al.2020 also shows that application of humic acid and NAA increase Test weight.

Seed yield and strover yield:

The data shows the response of different levels of fertilizer and growth regulators on yield of Safflower. The maximum Seed Yield 14.58q/ha, Stover yield 47.65 q/ha of Safflower was recorded in T9 [RDF @ 100% + Humic Acid (150PPM)] and the minimum Seed Yield 8.91 q/ha, Stover yield 34.02 q/ha found in T10 (control). Malac C.2015. Also present that the application of humic acid and fulvic acid significantaly increase the seed yield and strover yield.

Conclusion

The present study on safflower (Carthamus tinctorius L.) clearly showed that fertilizer dose and growth regulators together had a strong influence on plant growth and yield under Prayagraj conditions. T9 (RDF @ 100% + Humic Acid 150 ppm) produced the best overall results out of the ten treatments. Compared to all other treatments, the plants in this treatment grew taller, developed more branches, and gained more dry weight. This demonstrates how humic acid improves root and shoot development and helps the crop absorb nutrients more effectively when applied in conjunction with the full recommended dosage of fertilizer. T8 (RDF @ 100% + Seaweed Sap 200 ppm) performed the best, indicating that seaweed sap functions well with full RDF as well, but marginally less so than humic acid. The yield parameters also showed the similar pattern. In the end, T9 had the largest seed yield and stover yield (q/ha), as well as the greatest number of capitula per plant, more seeds per capitula, and superior test weight. Once more, T8 was the second-best treatment for all of these yield characteristics. However, for every growth and yield metric measured in the study, T10, the control plot based on standard farmer practice, produced the lowest values. This suggests that farmers who solely use traditional methods without managing growth regulators and nutrients properly are probably missing out on a significant portion of the possible output.

Overall, it can be said that the best combination for improving safflower growth and yield in this area is to apply RDF @ 100% and Humic Acid @ 150 ppm (T9). RDF @ 100% with Seaweed Sap @ 200 ppm (T8) is a good substitute in situations when humic acid is not readily available. To increase the profits from safflower farming, farmers are encouraged to switch from traditional methods to an enhanced nutrient management strategy.

References

1. Laftah SK, Alabdulla SA. Response of some growth traits of safflower (Carthamus tinctorius L.) to spray with humic acid under levels of phosphorus fertilizer. IOP Conf Ser Earth Environ Sci. 2022; 1060:012115.
2. Mazereku C, Gandure J, Ketlogetswe C. Effect of plant growth regulator on safflower oil yield. JETIR. 2023;10(7).
3. Weiss EA. Oilseed Crops: Safflower. 2nd ed. Oxford: Blackwell Publishing Ltd.; 2002. p. 93-129.
4. Al-Doori SAMA. Humic acid and plant density effect on growth, yield component and quality of safflower (Carthamus tinctorius L.). SABRAO J Breed Genet. 2025;57(6):2701-2712.
5. Malan C. Humic and fulvic acids: A practical approach. In: Proceedings of the Sustainable Soil Management Symposium; 2015 Nov 5-6. Agri Librium Publisher; 2015.
6. Keshavarz H, Modarres Sanavy SAM, Sadegh Gol Moghadam R. Impact of foliar application with salicylic acid on biochemical characters of canola plants under cold stress conditions. Not Sci Biol. 2016;8(1):98-105.
7. Korkmaz K, Kılıç R, Akgun M, Kara SM. Effects of combining phosphorus (P) and zinc (Zn) fertilization on PZn distribution and yield in safflower. J Plant Nutr. 2024;47(10):1585-1595.
8. Amoozad N, Zahedi M. Effects of humic acid application on physiological and biochemical characteristics of safflower cultivars under salinity and cadmium contamination. J Crop Sci Biotechnol. 2024;27:651-661.
9. Hemati A, Alikhani HA, Ajdanian L, Babaei M, Asgari Lajayer B. Effect of different enriched vermicomposts, humic acid extract and indole-3-acetic acid amendments on the growth of Brassica napus. Plants. 2022;11:227.
10. Haifaa MDI, Moses C. Effects of foliar and soil application of gibberellic acid (GA₃) at different growth stages on agronomic traits and yield of rice (Oryza sativa L.). J Agric Sci. 2022;14(6).
11. Senthil A, Djanaguiraman M, Chandrababu R. Effect of root dipping of seedlings with plant growth regulators and chemicals in transplanted rice (Oryza sativa L.). Madras Agric J. 2003;90:383-384.
12. Mahmood BJ, Muhammad KK. Foliar application effect of gibberellic acid on growth, yield components and some qualitative characteristics of linseed (Linum usitatissimum L.). ZANCO J Pure Appl Sci. 2022;34(6):69-78.
13. Arslan B, Culpan E. Effect of different gibberellic acid doses on seed yield, oil content and quality traits of safflower. J Glob Innov Agric Soc Sci. 2017;5(1):5-9.
14. Vafa ZN, Sohrabi Y, Sayyed RZ, Suriani NL, Datta R. Effects of the combinations of rhizobacteria, mycorrhizae, seaweed and supplementary irrigation on and yield in wheat cultivars. Plants. 2021;10(4):811.
15. Yuanyuan Y, Wang X, Chen B, Zhang M, Ma J. Seaweed extract improved yields, leaf photosynthesis, ripening time and net returns of tomato (Solanum lycopersicum Mill.). ACS Omega. 2020;5:4242-4249.
16. Hussain F, Manorama K, Vijayalakshmi V, Swarnalatha M, Sarla N. Estimation of iron and zinc content in different fractions of elite rice lines developed by marker assisted selection. J Res ANGRAU. 2013;41(4):106-108.
17. Hivare VS, Deotale RD, Dhongade AP, Pise SE, Raut DA, Blesseena A. Morpho-physiological traits and yield in safflower as influenced by foliar application of humic acid and NAA. J Soils Crops. 2019;29(2):348-353.
18. Amoozad N, Zahedi M. Effects of humic acid application on physiological and biochemical characteristics of safflower cultivars under salinity and cadmium contamination. J Crop Sci Biotechnol. 2024;27:651-661.
19. Metre NR, Deotale RD, Ghewande SS, Arsoode SV, Gowthami R. Effect of foliar application of humic acid through cow dung wash on chemical, biochemical and yield contributing parameters of green gram. J Soils Crops. 2013;23(2):369-376.