Studies on organic production of head lettuce (Lactuca sativa L)

Introduction

Lettuce (Lactuca sativa L.) is an important salad vegetable cultivated primarily for its edible leaves and compact head. Among the different lettuce types, head or iceberg lettuce is valued for its firm head and marketable fresh produce. Yield in head lettuce is closely associated with head development, fresh biomass accumulation and final head weight. Organic nutrient management provides an alternative approach for supplying nutrients while maintaining soil biological activity. Vermicompost supplies nutrients in relatively available forms and may improve plant growth and biomass accumulation through its nutrient content and biologically active constituents (Atiyeh et al., 2002) [1] . Biofertilizers can complement organic nutrient sources by improving nutrient acquisition, while biostimulants such as humic substances, vermiwash and seaweed extracts may influence nutrient-use efficiency and crop development. Previous studies have reported beneficial effects of integrated organic nutrient management on lettuce yield. Chatterjee (2015) [2] reported that FYM, vermicompost and biofertilizer combinations influenced yield-attributing characters and head fresh weight. Saha et al. (2020) [3] evaluated thirteen combinations of organic manure, Azophos and biostimulants and reported the highest head weight and yield with vermicompost + Azophos + humic acid, while vermicompost + Azophos + seaweed extract produced superior vegetative traits. The present investigation was therefore undertaken to assess the effect of FYM, vermicompost, Azophos and selected biostimulants on yield attributes and yield of head lettuce under the agro-climatic conditions of Latur.

Materials and methods

Experimental site and crop

The experiment entitled "Studies on organic production of Head lettuce (Lactuca sativa L.)" was conducted during Rabi 2025 at the Instructional-Cum-Research Farm, Department of Horticulture, College of Agriculture, Latur, VNMKV, Parbhani, Maharashtra, India. Iceberg head lettuce was used as the experimental crop. Seed was sown on 10 November 2025 and healthy seedlings were transplanted following nursery establishment.

R Darshan

Experimental design and treatments

The experiment was laid out in a randomized block design with 13 treatments and three replications. FYM and vermicompost were incorporated before transplanting according to treatment. Azophos biofertilizer was applied as a root dip for 30 min before transplanting at 250 ml L⁻¹. Humic acid (2 ml L⁻¹), vermiwash (10 ml L -1 ) and seaweed extract (2 ml L -1

) were applied as foliar sprays at 30, 45 and 60 days after transplanting (DAT).

Yield observations and statistical analysis

Yield-related observations were recorded at the appropriate stages of crop development. Days to head formation and days to maturity were recorded as phenological indicators associated with harvest readiness. Whole-plant fresh weight, head weight and root weight were recorded in grams per plant. Head yield per plot was recorded in kilograms and converted to gross and marketable yield per hectare. The data were subjected to analysis of variance appropriate for randomized block design, and treatment means were compared using the critical difference at the 5% level of significance following standard procedures for agricultural experiments (Panse et al., 2000) [4] .

Results and discussion

Fresh weight of whole plant

Whole-plant fresh weight differed significantly among treatments. T 7 recorded the highest fresh weight (672.13 g plant -1

), followed by T 9 (619.60 g) and T 10 (617.27 g), whereas T 2 recorded the lowest value (498.07 g plant -1 ). The greater fresh biomass under T 7 may be attributed to improved nutrient availability and uptake under the combined application of vermicompost, Azophos and humic acid. The result is consistent with the general response reported for integrated organic nutrient management in lettuce, where organic manure and biofertilizer combinations improved biomass and yield-related traits. Besas et al. (2020) [5] and Sriwichan et al. (2026) [6] reported beneficial effects of FYM, vermicompost and Azophos combinations on yield-attributing characters of lettuce.

Head weight

Head weight was significantly influenced by the treatments. The maximum head weight was recorded under T 7 (615.20 g plant -1 ), followed by T 9 (568.00 g) and T 10 (561.40 g), whereas T 2 recorded the minimum (436.67 g plant -1 ). The higher head weight under T 7 indicates greater accumulation of assimilates in the marketable head under the combined influence of vermicompost, Azophos and humic acid. Saha et al. (2020) [3] and Mohammed et al. (2022) [7] similarly reported maximum head weight with vermicompost 6 t ha -1 + Azophos + humic acid.

Root weight

Root weight was statistically non-significant among the treatments. The highest numerical root weight was recorded under T 8 (15.53 g plant - 1), followed by T 12 (15.37 g) and T 9 (15.13 g), whereas T 1 recorded the lowest numerical value (13.87 g plant -1 ). Since the treatment effect was non-significant, the numerical differences in root weight should not be interpreted as statistically distinct responses.

Head yield per plot

Head yield per plot was significantly influenced by the nutrient treatments. T 7 recorded the highest head yield (12.30 kg plot -1

), followed by T 9 (11.36 kg) and T 10 (11.23 kg), while T 2 recorded the lowest yield (8.73 kg plot -1 ). The superior performance of T 7 was consistent with its higher whole-plant fresh weight and head weight, indicating that the greater biomass accumulation was translated into higher head yield. The present findings are in close agreement with the findings of Saha et al. (2020) [3] and Mohammed et al. (2022) [7] Table 2

Gross yield

Gross yield differed significantly among treatments. The maximum gross yield was recorded under T 7 (497.88 q ha -1

), followed by T 9 (458.96 q ha -1

) and T 10 (457.23 q ha -1 ), whereas T 2 recorded the minimum gross yield (368.94 q ha -1

). The higher yield under T 7 can be associated with its superior head weight and head yield per plot. Similar improvements in lettuce productivity through vermicompost, biofertilizer and biostimulant combinations have been reported by Saha et al. (2020) [3] .

Marketable yield

Marketable yield was also significantly influenced by treatments. T 7 recorded the highest marketable yield (455.70 q ha -1 ), followed by T 9 (420.74 q ha -1

) and T 10 (415.85 q ha -1 ). The lowest marketable yield was recorded under T 2 (323.46 q ha -1

). The greater marketable production under T 7 reflects its higher head weight and head yield per plot, demonstrating that the treatment was effective in producing a larger proportion of harvestable head biomass.

Conclusion

The present investigation demonstrated that organic nutrient sources combined with Azophos and foliar biostimulants significantly affected yield attributes and yield of head lettuce. Vermicompost 6 t ha -1 + Azophos + humic acid (T 7 ) produced the highest whole-plant fresh weight, head weight, head yield per plot, gross yield and marketable yield. Root weight was not significantly influenced by the treatments. The superior yield performance of T 7 was associated with greater fresh biomass and head weight, indicating the potential of vermicompost-based integrated nutrient management with humic acid for improving head lettuce productivity under the conditions of the present study.

References

1. Atiyeh RM, Edwards CA, Subler S, Metzger JD. Effects of vermicomposts and composts on plant growth and nutrient availability. 2002.
2. Chatterjee R. Influence of nutrient sources on growth, yield and economics of organic lettuce production under foothills of eastern Himalayan region. 2015.
3. Saha S, Chatterjee R, Das A. Productivity enhancement of organic lettuce through use of organic manures, biofertilizers and bio-stimulants. Vegetable Science. 2020;47(1):44-48.
4. Panse VG, Sukhatme PV. Statistical Methods for Agricultural Workers. Indian Council of Agricultural Research, New Delhi; 2000.
5. Besas UP, Aceres LV, Caniones S. Potential of vermicompost drippings and other vermicomposting products on the growth and yield of lettuce. Southeastern Philippines Journal of Research and Development. 2020;25(1):33-46.
6. Sriwichan Y, Kaewsith S, Phrophayak J. Effect of vermicompost and organic fertilizer on the growth, yield, and quality of lettuce (Lactuca sativa L.). Food Agricultural Sciences and Technology. 2026;12(2):168-178.
7. Mohammed AA, Soylemez S, Sarhan TZ. Effect of biofertilizers, seaweed extract and inorganic fertilizer on growth and yield of lettuce (Lactuca sativa var. longifolia L.). Harran Tarım ve Gıda Bilimleri Dergisi. 2022;26(1):60-71.
8. How to cite this article: Darshan R, Jagtap V, Shinde V, Kamble V. Studies on organic production of head lettuce (Lactuca sativa L). International Journal of Research in Agronomy. 2026;9(9):1161-1163. doi: https://www.doi.org/10.33545/261806 0X.2026.v9.i9p.6661