Effect of Different Growth Regulators on Morphological Parameters, Yield and Nutritional Status of Pleurotus florida (Mont.) Singer

Abstract The rapid growth of the global population, coupled with shrinking agricultural land has created a pressing need for alternative food sources that are nutritious, affordable and space-efficient. Oyster mushrooms ( Pleurotus florida ) represent one such promising solution. They can be cultivated on agricultural wastes, require minimal resources and are well known for their rich nutritional composition, including protein, dietary fiber, vitamins and essential minerals. Despite this potential, productivity remains constrained by conventional cultivation approaches that overlook the role of plant growth regulators in enhancing yield and quality. The present study was designed to investigate how three widely used plant growth regulators- Naphthalene Acetic Acid (NAA), Indole Butyric Acid (IBA) and Gibberellic Acid (GA3)-applied at three concentration levels (5, 10 and 20 ppm), influence the growth, morphology, yield and nutritional composition of Pleurotus florida cultivated on wheat straw substrate. Among all nine treatments and the untreated control, the treatment designated T9 (wheat straw 5 kg + GA3 at 20 ppm) emerged as the most effective across nearly all parameters measured. T9 produced the fastest spawn running (12 days), earliest pin head initiation (16 days) and the quickest cropping timeline overall. In terms of morphology, T9 yielded the greatest number of fruiting bodies (90 per bag), the longest stalk (6.10 cm) and the widest cap diameter (8.93 cm). Total yield under T9 reached 1,416.66 g per bag, with a biological efficiency of 113.33%, compared to just 956.66 g and 76.53% in the untreated control. In terms of nutritional output, T9 recorded the highest levels of Iron (53.41 mg/100 g DW) and Zinc (5.49 mg/100 g DW). The second-best overall performer was T6 (wheat straw + IBA at 20 ppm), which led in Calcium (10.16 mg) and Nitrogen (4.32 mg) content, while T3 (wheat straw + NAA at 20 ppm) gave the highest Phosphorus (1.25 mg) and Magnesium (49.53 mg) values. The findings demonstrate that judicious application of growth regulators, especially GA3 at 20 ppm, can substantially improve both the productivity and nutritional value of Pleurotus florida . This has important implications for smallholder farmers, landless cultivators and agri-entrepreneurs seeking to enhance income and food security without requiring additional land or high capital input.