Mustard (Brassica juncea L.) is an important rabi oilseed crop in India and contributes substantially to domestic edible-oil production. The crop occupies about 6.9 million hectares with a production of 8.18 million tonnes and average productivity of 1,185 kg ha^-1 (Anonymous, 2024). In Punjab, mustard is cultivated on approximately 45,000 ha with an average productivity of 16.23 q ha^-1 (Punjab Agricultural University, 2024-25). Nutrient management is a major determinant of mustard growth, yield formation and resource-use efficiency. Integrated use of inorganic fertilizers with organic amendments can improve nutrient availability and sustain crop productivity. Previous research in mustard has also demonstrated the importance of balanced sulphur nutrition for growth, yield attributes and seed production (Chandel et al., 2019), while recent field research in Punjab has confirmed positive responses of Brassica crops to sulphur-based nutrient management (Saral et al., 2025). Similarly, nitrogen management has been shown to modify dry-matter accumulation and yield formation in Indian mustard (Keerthi et al., 2017).
       
Organic nutrient sources such as farmyard manure (FYM) and vermicompost can supply nutrients progressively and improve soil physical and biological conditions. Their integration with mineral fertilizers may provide a more balanced nutrient supply than reliance on a single nutrient source. However, nutrient availability can also influence crop canopy development and tissue nutrient status, potentially altering the crop environment experienced by herbivorous insects. Thus, productivity gains from integrated nutrient management should be assessed together with pest dynamics rather than considering yield response in isolation.
       
Nutrient status can also influence herbivore pressure by changing canopy development and plant nutritional quality. Nevertheless, the direction and magnitude of nutrient-pest relationships may depend on crop stage, nutrient source and pest species. Evidence linking integrated nutrient management with both productivity and pest incidence in mustard under the semi-arid conditions of Punjab remains limited. Therefore, the present study evaluated different combinations of mineral fertilizer, sulphur, FYM and vermicompost for their effects on growth, yield attributes, yield and insect pest population in mustard under Punjab conditions.

The experiment was conducted at the Agricultural Research Farm, Guru Kashi University, Talwandi Sabo, Bathinda, Punjab, India (29°57’N, 75°07’E; 213 m A.S.L.) during rabi season (October 2025 to April 2026). The climate is sub-tropical semi-arid; mean maximum temperature ranged from 14.3°C (50^th SMW) to 35.1°C (11^th SMW) and minimum from 3.0°C to 18.6°C during the crop period. Total rainfall of 63.2 mm was received in six rainy days during the season. Composite soil samples (0-15 cm and 15-30 cm) collected prior to sowing revealed loamy sand texture, neutral to slightly alkaline reaction (pH 7.6-8.0), negligible salinity (EC 0.10-0.15 dS/m), low organic carbon (0.12-0.24%), low available nitrogen (103-206 kg/ha), adequate available phosphorus (26.2 kg/ha) and adequate available potassium (150-217 kg/ha) (Package of Practices for Rabi Crops, 2024-25). The experiment was laid out in a Randomized Block Design (RBD) with twelve treatments and three replications (36 plots; net plot size 3.0 m x 3.0 m = 9.0 m²). Treatment details are given in Table 1. Symbols used: VC = vermicompost; FYM = farmyard manure; S = sulphur at RDF; RDF = recommended dose of fertilizer (Urea + SSP + MOP); NPK = NPK 19:19:19 @ 100 kg/ha; SSP = single super phosphate; MOP = muriate of potash.


 
Crop management
 
Pioneer 45S46 was sown on 3 October 2025 using a manually operated seed drill at 30 cm row spacing with a seed rate of 3.75 kg ha^-1. Full phosphorus and 50% of the nitrogen dose assigned to each treatment were applied basally; the remaining 50% nitrogen was top-dressed after the first irrigation at 35 DAS. Thinning was performed at 22 DAS to maintain 15 cm plant-to-plant spacing. Three irrigations were applied at 35, 75 and 95 DAS. FYM and vermicompost were incorporated into the soil 15 days before sowing and sulphur was applied as elemental sulphur at the recommended dose during the final ploughing. For pest management, thiamethoxam 25 WG @ 100 g ha^-1 or dimethoate 35 EC @ 750 mL ha^-1 were applied when pest populations exceeded the economic threshold level. Fungicidal sprays of mancozeb 75 WP @ 625 g ha^-1 and difenoconazole 25 EC @ 250 mL ha^-1 were applied for Alternaria blight. Plant height, number of leaves plant^-1 and number of branches plant^-1 were recorded at 30 and 60 DAS and maturity on five tagged plants per plot. Yield attributes (siliquae plant^-1, siliqua length, seeds siliqua^-1 and 1000-seed weight) were measured at physiological maturity. Grain yield, stover yield and harvest index were recorded at harvest. Insect population (insects plant^-1) was counted on four tagged plants per plot at 30 DAS, 60 DAS and maturity using a 10x hand lens. The five observed pest species were mustard aphid (Lipaphis erysimi), mustard sawfly (Athalia lugens proxima), painted bug (Bagrada hilaris), cabbage butterfly (Pieris rapae) and diamondback moth (Plutella xylostella).
       
Data were subjected to analysis of variance (ANOVA) for the randomized block design as described by Cochran and Cox (1967), using OPSTAT software. Treatment means were compared at the 5% level of significance using the critical difference (CD) test. Pearson correlation coefficients (r) were calculated from treatment means (n = 12) for grain yield, stover yield, plant height at maturity and insect population at 30 DAS, 60 DAS and maturity. Two-tailed significance of correlation coefficients was evaluated at P≤0.05. Because the correlation analysis used treatment means, the resulting associations should be interpreted as treatment-level relationships rather than independent plant-level relationships.

Plant height
 
Plant height increased progressively with crop age and nutrient input (Table 2). At 30 DAS, the tallest plants (25.33 cm) were recorded under T12, followed by T11 (24.33 cm) and T10 (23.00 cm), whereas T1 recorded the minimum (9.00 cm). At 60 DAS, T12 again recorded the maximum height (119.67 cm), followed by T11 (115.00 cm) and T10 (110.67 cm). At maturity, T12 reached 172.00 cm compared with 94.00 cm in T1. The progressive enhancement in plant height with combined inorganic-organic inputs is attributed to improved nitrogen and phosphorus availability, better soil moisture retention and stimulation of beneficial soil microflora that promote cell elongation and apical meristem activity (Mehta and Singh, 2019; Mondal et al., 2015). Similar responses to nutrient management and sulphur nutrition have been reported in mustard (Thaneshwar et al., (2017) and Arya et al., (2007); Chandel et al., 2019; Keerthi et al., 2017; Saral et al., 2025).


 
Number of leaves and branches per plant
 
The number of leaves plant^-1 followed a similar treatment response to plant height (Table 2). Maximum leaves at maturity (17.67) were recorded under T12, followed by T10 and T11 (17.33 each), while T1 and T2 recorded the minimum (11.00 each). Number of branches at maturity was highest in T11 (14.33) and T12 (14.00) and lowest in T1 and T2 (5.33 each). The greater branching under integrated nutrient treatments may be associated with improved nutrient availability and greater vegetative growth. Comparable positive responses of growth attributes to integrated or sulphur-based nutrient management have been reported in mustard (Shorna et al., 2020; Dongrawar et al., 2007; Rundal et al., 2013; Chandel et al., 2019).
 
Yield attributes and crop yield
 
The number of siliquae plant^-1 differed significantly among treatments (Table 3). The maximum value was recorded in T11 (337.67), followed by T12 (316.00) and T10 (313.33), while T1 recorded the minimum (109.33). Siliqua length was maximum in T11 and T12 (8.67 cm each) and minimum in T1 (3.67 cm). Seeds siliqua^-1 were highest in T12 (17.00) and were statistically at par with T9, T10 and T11 (16.67 each). Test weight showed a non-significant trend, ranging from 3.48 g in T1 and T2 to 3.99 g in T11. The improvement in yield attributes under integrated nutrient supply is consistent with earlier reports for mustard (Kasved et al., (2010); Manna and Siddique, 2025).


       
Grain yield increased significantly with increasing intensity of integrated nutrient inputs. T12 recorded the highest grain yield (22.33 q ha^-1), followed by T11 (22.00 q ha^-1) and T10 (21.00 q ha^-1), which were statistically at par, whereas T1 recorded the minimum (10.67 q ha^-1). Thus, T12 produced 109% higher grain yield than the control. The higher yield under T12 may be attributed to the combined supply of nutrients from NPK, sulphur, vermicompost and FYM, which supported vegetative growth and reproductive development (Aulakh, 2010; Basu and Patel, 2022). The role of sulphur in mustard productivity is well established and recent work has demonstrated positive responses of Brassica crops to sulphur-based nutrient management (Chandel et al., 2019; Saral et al., 2025; Manna and Siddique, 2025). Stover yield was highest in T11 and T12 (42.67 q ha^-1 each) and lowest in T1 (19.67 q ha^-1). Harvest index ranged from 31.36% in T6 to 36.46% in (Maheshbabu et al., 2008).
 
Insect pest population
 
Insect population increased with increasing intensity of organic amendment across the observed growth stages (Table 3). At 30 DAS, T12 recorded the highest observed population (12.83 insects plant^-1), whereas T1 recorded 4.17 insects plant^-1. At 60 DAS, T12 recorded 15.88 insects plant^-1 compared with 10.12 insects plant^-1 in T1. At maturity, T12 (14.25), T11 (14.08) and T10 (13.45) had the highest observed populations. Five pest species were observed: Lipaphis erysimi, Athalia lugens proxima, Bagrada hilaris, Pieris rapae and Plutella xylostella. The higher pest counts in treatments supporting greater crop growth may be associated with differences in canopy development and plant nutritional status; however, these mechanisms were not directly measured in the present experiment and should therefore be interpreted as plausible explanations rather than demonstrated causal effects. The pest observations reinforce the need to combine nutrient management with regular monitoring and need-based integrated pest management, consistent with the broader emphasis on integrated pest protection in oilseed crops (Obermeier et al., 2022; Golizadeh et al., 2025).
 
Correlation
 
Pearson correlation analysis showed strong positive treatment-level associations between crop performance and insect population (Table 4). Grain yield was positively correlated with insect population at 30 DAS (r = 0.979), 60 DAS (r = 0.857) and maturity (r = 0.971), while plant height at maturity was correlated with insect population at 30 DAS (r = 0.870), 60 DAS (r = 0.942) and maturity (r = 0.886). Grain yield and stover yield were also strongly correlated (r = 0.972). With 12 treatment means, all reported correlation coefficients were significant at P<0.001. These associations indicate that treatments producing greater crop growth and yield also tended to have greater insect populations; they do not, by themselves, establish that higher nutrient availability caused insect multiplication. Therefore, integrated nutrient management should be accompanied by regular pest surveillance and need-based integrated pest management.

Among the twelve nutrient-management treatments evaluated, T12 [NPK 19:19:19 @ 100 kg ha^-1 + sulphur + vermicompost (5 t ha^-1) + FYM (10 t ha^-1)] produced the highest plant height at maturity (172.00 cm), grain yield (22.33 q ha^-1) and stover yield (42.67 q ha^-1), while T11 produced the highest number of siliquae plant^-1 (337.67). The highest observed insect populations occurred in T12 across the three assessment stages. The positive treatment-level correlations between productivity and insect population indicate that high-yielding nutrient-management treatments should be accompanied by regular pest monitoring and need-based integrated pest management under Punjab conditions.

The authors acknowledge the Department of Agronomy, Guru Kashi University, Talwandi Sabo, Punjab, for providing the facilities required to conduct this research.
 
Disclaimers
 
The views and conclusions expressed in this article are solely those of the authors and do not necessarily represent the views of their affiliated institutions. The authors are responsible for the accuracy and completeness of the information provided, but do not accept any liability for any direct or indirect losses resulting from the use of this content.
 
Informed consent
 
All animal procedures for experiments were approved by the Committee of Experimental Animal care and handling techniques were approved by the University of Animal Care Committee.

 The authors declare that there are no conflicts of interest regarding the publication of this article. No funding or sponsorship influenced the design of the study, data collection, analysis, decision to publish, or preparation of the manuscript.