One of the most valuable cereal crops, wheat (Triticum aestivum L.), is a member of the Poaceae family of grasses and is consumed in large quantities in India. After rice and maize, it is the cereal that is produced the most. India has advanced significantly over the previous 40 years to become the second-largest wheat producer in the world. In temperate regions, wheat is the most common crop grown for human consumption and animal feed. All of the qualities and trails needs to make bread are present in flour derived from bread wheat. 

The main factor behind bread wheat's supremacy in the baking sector is its unique viscoelastic gluten protein complex, which makes it the best cereal grain for leavened bread baking. The quality of bread is highly correlated with the fractions of gluten, gliadins, and glutenins (Hadzi et al., 2013). Anon (2013) reports that wheat is planted on 10.24 lakh hectares in Gujarat, producing 29.44 lakh tonnes of total output and 2803 kg ha-1 productivity.  Most of the soil in Gujarat's Saurashtra region is medium-black calcareous soil with low levels of sulphur and nitrogen. Strategic fertilizer application could increase wheat crop productivity and protein content.  Gujarat's productivity is comparatively lower due to a number of issues, including inadequate irrigation systems, unbalanced fertilizer use, and a lack of understanding of contemporary agronomic practices like appropriate genotypes, appropriate sowing times, seed rates, spacing, weed control, fertilization, and plant protection measures, among others. The second-most important nutrient for plants is phosphorus, which is crucial for getting the most crop production. Numerous physiological processes, such as photosynthesis, respiration, energy storage, and cell division and enlargement, depend on it.

Phosphorus that plants need for healthy growth and yield. However, because soluble forms are not present in the soil, it is thought to be one of the most restricting factors in many crop production systems. According to Nisha et al. (2014), the formation of complexes with Al or Fe in acidic soils or Ca in calcareous soils immobilises about 80% of applied phosphorus fertilisers. In the soil of various land forms in southern Saurashtra, available phosphorus content ranged from 5.6-42.2 kg ha-1, with an overall mean of 19.4 kg ha-1, according to Savalia (2005). Improved uptake and utilisation efficiency are two factors contributing to plant phosphorus efficiency (Balemi and Negisho 2012). Another essential nutrient found in all plant nutrients is sulphur, which is also a component of amino acids, the building blocks of protein. The ranges of sulphur content in cereal crops are 0.16 to 0.20%. Plants have a critical sulphur content of 0.20-0.25%, below which crops exhibit deficiencies in sulphur and react negatively to sulphur fertiliser. Not only is sulphur essential for plant growth, but it also improves grain quality. One essential macronutrient is sulphur, which is mostly made during the synthesis of cysteine and methionine. It contributes to the synthesis of disulfide bonds in proteins as well. The amount of sulphur present also has a significant impact on the bread wheat's storage proteins' quality (Pompa et al., 2009). Wheat production and quality are greatly impacted by sulphur deficiency. Because of the disulfide bonds that form from the sulphydryl groups of cysteine, a deficiency in sulphur reduces grain size and baking quality (Gyori, 2005). Consequently, this experiment was conducted with these factors in view.

The current study examined the effects of phosphorus and sulphur levels on wheat (Triticum aestivum L.) yield and economics during the rabi season of 2015-16 at the College Farm, College of Agriculture, Junagadh Agricultural University, Junagadh (Gujarat) with a pH of 8.10 and an EC of 0.36 dS m-1, the soil of the experimental plot had a silty loam texture and was slightly alkaline in reaction.  In terms of available nutrients, the soil had low levels of nitrogen (242 kg  ha-1), medium levels of phosphorus (39.20 kg ha-1), high levels of potash (292 kg ha-1), and medium levels of sulphur (19.05 ppm).  A total of 12 treatment combinations were used in the factorial randomized block design experiment. The phosphorus levels were 0.00 kg ha-1 (P0), 30.00 kg ha-1 (P1), 60.00 kg ha-1 (P2), and 90.00 kg ha-1 (P3), and the sulphur levels were 0.00, 20.00, and 40.00 kg ha-1 as S0, S1, and S2, respectively. There were three replications of these treatments. In the form of urea (46% N), di-ammonium phosphate (46% P2O5 and 18% N), and muriate of potash (60% K2O), the recommended dose of nitrogen, phosphorus, and potassium (N:P2O5:K2O @ 120:60:60 kg ha-1) was applied as a basal application and the remaining amount as rest. 30 days after sowing, 60 kg ha-1 of nitrogen was applied. According to the treatments, sulphur was applied in the form of Cosavet (90% S).

A. Effect of phosphorus on yield 

The results revealed that different treatments of phosphorus manifested significant influence on yield attributes and yield of wheat (Table 1). Application of 90 kg P2O5 ha-1 (P3) recorded significant maximum spike length (8.7 cm), number of spikelets spike-1 (15.9), grain yield (4451 kg ha-1) and straw yield (6886 kg ha-1) which was found at par with P2 (i.e. 60 kg P2O5 ha-1). Yield attributes viz., maximum spike length by 11.53%, 6.41%, number of spikelets spike-1 by 14.38%, 10.07%  and ultimately increased grain yield by 26.41%, 13.44%  and straw yield by 14.46%, 08.85%, respectively by 90 kg P2O5 ha-1 (P3) and P2 (i.e.60 kg P2O5 ha-1) over the control (P0). This could be because the plant used more phosphorus from its native source as a result of the higher amount of phosphorus applied mobilizing native phosphorus. It is also true that phosphorus plays a role in the metabolism of organic compounds and is necessary for higher nitrogen utilization. One of phosphorus's major functions is to increase the number of tillers in cereals, which explains the increase in yield attributes and yield with phosphorus levels. The metabolism and enzymatic reactions that lead to an increase in total and effective tillers are facilitated by phosphorus. One essential component and co-enzyme for photosynthesis and protein synthesis is phosphorus. This may have resulted in an increase in grain and straw yield, spike length, and spikelet spike-1. The findings of Khan et al. (2007); Gaur and Singh (2010); Hussain et al. (2011); Arshad et al. (2016) are corroborated by these results.

B. Effect of sulphur on yield

Table 1 shows that varying sulphur levels significantly impact yield and attributes, with 40 kg S ha-1 fertilization resulting in higher spike length, spikelet number, grain yield, and straw yield. S0 (control) showed the lowest recorded yield and yield attributes. The corresponding increases with 40 and 20 kg S ha-1 over control were in the length of the spike by 10.25%, 5.12%, number of spikelets spike-1 by 15.32%, 10.21%, grain yield by 28.13%, 15.95%, and straw yield by 11.13%, 3.37%. The application of sulphur may have increased various yield attributes and yields because sulphur is an essential amino acid that aids in the formation of chlorophyll, the photosynthetic process, the activation of enzymes, and the formation of seeds. It appeared that fertilization increased chlorophyll synthesis and photosynthetic activity, which aided in the promotion of vegetative growth. In the case of wheat crops, the results are in close agreement with those reported by Ganeshamurty et al. (1994); Vyas et al. (1997); Orman and Ok (2012); Singh and Bhadoria (2013); Khan et al. (2015); Kharub and Dhillon (2007).

C. Interaction effect of phosphorus and sulphur on yield 

Table 3 shows that there is a significant interaction effect between the levels of phosphorus and sulphur on grain yield. Notably, the wheat crop fertilized with 90 kg P2O5 ha-1 + 40 kg S ha-1 (P3S2) produced the maximum grain yield of 4937 kg ha-1, which remained statistically equivalent to treatment combinations of P3S1, P2S1, P1S2, and P0S2. Significantly, the control treatment (i.e., P0S0) produced a lower grain yield of 2711 kg ha-1. It could be because sulphur and phosphorus are absorbed as anions and work in concert with one another. The outcomes support the conclusions of the following studies on wheat crops: Marok and Dev (1980); Randhawa and Arora (2000); Islam et al. (2006); Abdallah et al. (2013).

D. Effect of phosphorus and sulphur on economics  

The information presented in Table 3 made it abundantly evident that applying 90 kg of P2O5 ha-1, which was closely followed by 60 kg of P2O5 ha-1, secured the highest gross and net returns of ` 91,666  ha-1 and ` 47,637 ha-1, respectively, as well as a B: C ratio of 2.08. In the case of sulphur, however, application of 40 kg S ha-1, closely followed by 20 kg S ha-1, secured maximum gross and net returns of ` 89,813 ha-1 and ` 44,795 ha-1, respectively, along with a B: C ratio of 2.00, due to additional grain and straw yield obtained high under these treatments.

Table 1:  Effect of phosphorus and sulphur levels on yield attributes and yield of wheat crop.

Table 2:  Economics of different treatments.

Table 3:  Interaction effect of phosphorus and sulphur on grain yield.

Appendix- I: Economic of different treatment combinations

Appendix-II: Cost of cultivation treatment wise.

Based on the findings of a year-long field study, it seems reasonable to conclude that irrigated wheat (GW 496) should be fertilized with 90 kg P2O5 ha-1 + 40 kg S ha-1 along with a nitrogen dose based on 120 kg N ha-1 in order to increase yield and net realization.

Deen Dayal Bairwa, Rajendra Prasad Meena, Mohan Lal Jat, Bhawani Singh Prajapat and J.M. Modhvadia  (2024). Impact of Levels of Phosphorus and Sulphur on Yield and Economics of Wheat (Triticum aestivum L.) Crop. Biological Forum – An International Journal, 16(1): 247-250.