INTRODUCTION Peanut (Arachis hypogaea), also called groundnut, earthnut, or goober, a legume of the pea family (Fabaceae), has multifaceted uses as grain, oilseed, and serves as raw material for more than 300 industrial products like flour, soaps, and plastics. Groundnut seed is rich in oil and protein content varying from 44 % to 56% and 22% to 30% respectively on dry seed basis. (Savage and Keenan 1994). The world production of groundnut was 49 million tonnes (2019), a 7% increase over the production in 2018. China ranks first with 36% of global production, followed by India (14%). Currently it occupies an area 4,825 thousand hectares with a production of 9,952 thousand tonnes and a productivity of 2063 kg/ha (Indiastat, 2021). The major problem encountered in groundnut production is the formation of immature and ill filled pods due to its indeterminate nature leading to uneven maturity. This in turn leads to reduced pod filling efficiency with ultimate reduction in yield. Thus, there is a need to identify proper measures to arrest the flowering at later stages of crop growth so that the food from source is diverted to early formed pods only leading to perfect filling with decrease in number of unfilled, immature pods. To overcome this uneven maturity, there is a need to arrest flower formation at later stages of crop growth (Vinothini et al., 2018). This study was thus taken up to identify the appropriate plant growth regulator to arrest flowering at later stages of crop growth and which ultimately increase the yield (Krishnamurthy 1981). MATERIAL AND METHODS A field experiment was conducted at the Research farm of Seed Research and Technology Centre, Rajendranagar, Hyderabad, in a Randomized Block Design replicated thrice to evaluate the influence of plant growth regulators on flowering and yield in groundnut var. Kadiri Lepakshi (K-1812) during Rabi, 2021-22. The seed of the groundnut variety Kadiri Lepakshi (K 1812) was procured from Agricultural Research Station, Kadiri and used as a source seed material for the investigation. The plot size for each treatment is 4 × 3 m2 and the crop was sown following a row-to-row spacing of 22.5 cm and plant to plant spacing of 10 cm. Crop was sown on 25th November 2021 and the various treatments i.e., foliar application of plant growth regulators such asT1-Mepiquat chloride @ 500 ppm, T2-Mepiquat Chloride @ 1000 ppm, T3- Ethrel @ 200 ppm, T4-Ethrel @ 400 ppm, T5- CCC @ 500 ppm, T6- CCC @ 1000 ppm, T7-MH @ 100 ppm, T8- MH @ 200 ppm, T9- NAA @ 100 ppm, T10- NAA @ 200 ppm and T11- Control were imposed 60 days after sowing, to prevent flowering in subsequent development stages. The observations were recorded on crop growth and yield parameters from 10 plants in each plot. The test weight of the seeds was taken from a random sample of 100 seeds and the plot yield (kg) was also recorded. The data collected was analysed statistically adopting the procedure described by Panse and Sukhatme (1985). RESULTS A field experiment on the influence of plant growth regulators on flowering and seed yield in groundnut (Arachis hypogaea L.) was conducted during Rabi (2021-2022) with variety K-1812. To achieve higher yield, it is crucial to stop production of new flowers after 60 DAS to prevent the mobilisation of resources to flowers as it may benefit the availability of enough days for finishing the seed filling. Among treatments, T1- mepiquat chloride @ 500 ppm (42) recorded significantly lowest number of flowers /plant after spraying significantly high test weight (48.55 g) and more yield per plot (6.84 kg/plot) compared to untreated control (136 number of flowers, 40.20 g test weight and 5.32 kg plot yield respectively). Regardless of concentrations, all other PGRs except Ethrel @ 200 ppm showed a significant reduction in the number of flowers/plant over the control (Table 1). The plants treated with mepiquat chloride @ 500 ppm produced the maximum number of double-seeded mature pods (13), compared to less number of mature double-seeded pods plant-1andmore number of flowers plant-1in control. The number of double-seeded immature pods plant-1, single-seeded immature pods plant-1, and ill-filled pods plant-1 were reported as 8, 3, and 8 in the control, respectively (Table 2). Plants treated with Mepiquat Chloride @ 500 ppm recorded highest weight of double-seeded mature pods plant-1 (33.82 g)which was on par with T9- NAA @ 100 ppm (32.98), T8 MH @ 200 ppm (31.24), T6 CCC @ 1000 ppm (29.64) and T4 Ethrel @ 400 ppm (29.32). Significantly low weight of double-seeded mature pods plant-1(27.54) was observed in the untreated control. When compared to Mepiquat Chloride @ 500 ppm, the negative pod features of the weight of double seeded immature pods plant-1, weight of single-seeded immature pods plant-1 and weight of ill-filled pods plant-1 were reported as 3.08, 0.43, and 1.11 g respectively in Control (Table 3). Significantly more number of mature seeds/plant (62) were recorded with Mepiquat Chloride @ 500 ppm which was on par with T2-Mepiquat Chloride @ 1000 ppm (59), T3-Ethrel @ 200 ppm & T6-CCC @ 1000 ppm (58), T8-MH @ 200 ppm (57) and T10-NAA @ 200 ppm (54). The weight of mature seeds plant-1was maximum in T1-Mepiquat Chloride @ 500 ppm (27.05 g) followed by T9-NAA @ 100 ppm (24.63), T8-MH @ 200 ppm (22.95) and T6-CCC @ 1000 ppm (22.76) which are on par with the best treatment. When compared to Mepiquat Chloride @ 500 ppm, the negative seed characteristics, such as the number of immature seeds plant-1 and their weight, were reported as 14 and 2.92 g in the Control (Table 4). DISCUSSIONS The impact of plant growth regulators on the phases of groundnut development has been the subject of several investigations. The current study found that foliar application of mepiquat chloride @ 500 ppm on groundnut at 60 DAS arrests flowering at later stages. Similar observation of reduction in flowers was recorded by Avinasha et al. (2019) with the spraying of mepiquat chloride. This reduction of flowers is desirable as it will help in the efficient dissemination of food reserves to early formed pods thereby increasing the number of filled pods/plant leading to higher productivity. These results are also in conformity with the findings of Pushp and Virender (2013) who reported that foliar application of mepiquat chloride in groundnut alters the source-sink relationship which leads to diversion of assimilates to the already formed pods. With the increase in the number of mature pods, there is a proportional increase in the seed weight which is majorly contributed by mature seeds with the application of mepiquat chloride as confirmed by Pushp sharma et al., (2013).