INTRODUCTION Guava is an important commercial fruit crop. It is successfully grown under both tropical and subtropical climates. It is commonly called a poor man’s apple in the tropics and known for its delicious, pleasant aroma and outstanding nutritional values throughout the world. It is highly rich in minerals like phosphorus and calcium. In India, it occupies an area of 276 thousand ha with a production of 4253 thousand Mt (Anonymous, 2020). Different biotic and abiotic factors are responsible for low yields of guava. Out of biotic ones, the insect-pests have been reported to attack guava at different stages particularly during rainy season crop. It is infested by around 80 species of insect pests like fruit flies, bark eating caterpillar, capsule borer, mealy bug, hairy caterpillar and many sucking pests, out of which fruit fly is the major one causing a heavy loss in the yield (Butani, 1979; Tandon and Verghese, 1987; Verghese and Sudhadevi, 1998; Singh et al., 2003; Rajitha and Viraktamath, 2005; Atwal and Dhaliwal, 2009). Fruit flies belong to the family Tephritidae which is one of the largest, most diversified families of order Diptera. In India, 392 species of fruit flies have been recorded (Kapoor, 1993). From economic point of view, fruit flies, Bactrocera dorsalis (Hendel) and Bactrocera zonata (Saunders) are highly destructive pests of peach, pear, guava and kinnow mandarin causing up to 80, 70, 100 and 60 to 80 per cent fruit infestation, respectively depending on population, locality, variety and season (Kumar et al., 2011; Sharma et al., 2011; Bajaj and Singh 2020). In general, fruit flies are very difficult to manage due to the fact that they are polyphagous, multivoltine, adults have high mobility and fecundity, and all the developmental stages are unexposed (Vargas et al., 2010, Kumar and Agarwal, 1998). Farmers use a variety of chemical insecticides for the management of fruit fly in guava. Most of the insecticidal treatments are ineffective to control fruit fly since eggs and maggots remain protected in the host tissues and only adults are exposed. Moreover, the use of chemical insecticides causes residue problems. So, there is strong need for integrated pest management practices (Vargas et al., 2008; Verghese et al., 2004). As an alternate strategy, methyl eugenol traps can be used for male annihilation technique (MAT) for the management of Bactrocera spp. (White and Elson Harris, 1992; Bhowmik et al., 2015; Singh et al., 2015). Methyl eugenol traps have been standardized by different institutes, but this technique is still less exploited in India. Fruit flies can be controlled over local area upto some extent by fruit bagging, field sanitation, protein bait, annihilation technique, growing fly resistant genotypes, augmentation of biological control, incorporation of neem seed kernel extract and insecticides (Akhtaruzzaman et al., 1999; Singh et al., 2003; Dhillon et al., 2005). Therefore, in the present studies, methyl eugenol traps in combination with other eco-friendly approaches were evaluated for the management of fruit fly in guava. MATERIALS AND METHODS The studies were carried out at farmer’s field in village Sunderpur, District Rohtak, Haryana during rainy season of 2016-17. The methyl eugenol traps were purchased from PAU, Ludhiana and fixed with the 7 year old guava trees var. Hisar Safeda at equidistance from each other @40 traps ha-1 in the last week of May. The following eco-friendly management strategies were evaluated against Bactrocera spp. Eco-friendly management strategies S1: PAU Methyl eugenol trap @40 traps ha-1 S2: S1+3 sprays of Neem Seed Kernel Extract (NSKE) 5% (1st spray in last week of June, subsequent sprays at 15 days interval) S3: S1+2 sprays of NSKE 5% (1st spray in last week of June and 2nd at 15 days interval) S4: S1+1 spray of NSKE 5% in last week of June S5: S1+Mulching (Black polythene sheet) under tree canopy S6: S1+Raking under tree canopy twice (1st at 1st fortnight of June and 2nd at 2nd fortnight of June) S7: S1 + Collection and destruction of dropped fruits on alternate days S8: 3 sprays of NSKE 5% (1st spray in last week of June, subsequent sprays at 15 days interval). S9: 2 sprays of NSKE 5% (1st spray in last week of June and 2nd at 15 days interval) S10: Untreated control S8, S9 and S10 were laid out at an isolation distance of 300 m from other strategies (S1 to S7) so as to avoid the effect of methyl eugenol trap. The experiment was laid out in Randomised Block Design in 3 replications (1 tree replication-1).The fallen fruits (infested by fruit flies) were collected and destroyed on alternate days by burying them into soil at faraway place so as to prevent multiplication of fruit fly population. The fruit fly catches were collected and removed from the traps every week. Recording of observations: a) Fruit infestation. For this, a sample of 10 fruits at random were collected at weekly interval from each replication during 31st to 36th Standard Meteorological Week. The infested (based on oviposition puncture) and healthy fruits were counted and weighed separately. The fruit infestation on number and weight basis were calculated by using formula given by Abott (1925). % of fruit damage (number basis) = (Number of damaged fruits)/█(Total number of fruits@(damaged+healthy) )×100 % of fruit damage (weight basis) = (Weight of damaged fruits)/█(Total weight of fruits@(damaged+healthy) ) ×100 b) Marketable yield. Reduction in yield due to fruit fly damage was worked out by using data on per cent fruit damage on weight basis recorded at weekly interval during crop season Marketable yield = Total yield – Reduction in yield c) Benefit cost ratio Benefit cost ratio of each management strategy was worked out by using the following formula Benefit cost ratio= (Value of increased yield (Rs))/(Total cost incurred on management strategy(Rs)) Statistical analysis of data. The obtained data were statistically analyzed using angular root transformation wherever needed. RESULTS AND DISCUSSION Fruit infestation due to guava fruit fly, Bactrocera spp. On the basis of effects of different management strategies against guava fruit fly Bactrocera spp. on guava crop, it is evident that strategy S2 (methyl eugenol traps + 3 sprays of NSKE 5%) was most effective among all the strategies (Table 1). There was minimum fruit infestation in S2 i.e. 38.33 and 35.82 per cent both on number and weight basis, respectively and that was at par with strategy S3 (methyl eugenol traps + two spray of NSKE 5%) i.e. 47.77 and 44.87 per cent both on number and weight basis, respectively. In rest of the management strategies, S1, S4, S5, S6, S7 and S8, the fruit infestation varied from 54.44 to 57.78 per cent and 49.27 to 54.81 per cent on number and weight basis, respectively. The management strategy S9 was found to be the least effective as there was high infestation i.e. 64.44 and 65.04 per cent on number and weight basis, respectively which was at par with untreated control (75.04 % and 72.32% on number and weight basis, respectively). Under different management strategies the highest reduction in fruit fly infestation over untreated control in guava was recorded in S2 (methyl eugenol + three sprays of NSKE 5%) i.e. 39.97 and 41.45 per cent both on number and weight basis, respectively followed by S3 (methyl eugenol +two spray of NSKE 5%). The other management strategies S1, S4, S5, S6 and S7 were having almost similar reduction in percentage infestation. The management strategy S9 (two sprays of NSKE 5%) was found to be the least effective as it was having only 18.08 and 12.43 per cent reduction in infestation both on number and weight basis respectively. Marketable yield of guava under different management strategies. The data presented in Table 2 indicated that the highest marketable yield of guava (95.76 q ha-1) was recorded in S2 during rainy season as against 34.78 q ha-1in untreated control. In the remaining management strategies, the marketable yield ranged from 44.92 to 78.36 q ha-1 being lowest in S9. In S2, there was an increase of 175.33 per cent in marketable yield of guava over untreated control followed by S3 (125.3%) whereas minimum increase in marketable yield over control was obtained in S9 (29.15%). There was not much difference in total marketable yield in remaining management strategies i.e. S1, S4, S5, S6, S7 and S8. On the basis of increase in marketable yield of guava over untreated control, the efficacy of various management strategies in descending order was S2, S3, S7, S4, S5, S6, S1, S8 and S9. Economics of different management strategies. The data presented in Table 3 indicated the economics of different management strategies against Bactrocera spp. during rainy season. The highest net profit (Rs. 65674 ha-1) was obtained in S2 (methyl eugenol traps + 3 sprays of NSKE 5%) followed by S3 (methyl eugenol + two sprays of NSKE 5%) i.e. Rs. 44173 ha-1. The total cost incurred on management strategy was found to be almost similar in S2 and S5 (methyl eugenol traps + mulching under tree canopy) but S5 proved to be the least effective strategy showing minimum net profit (Rs. 21611 ha-1). On the basis of net profit, different management strategies were placed in descending order as S2, S3, S7, S4, S1, S6, S8, S5, S9. The highest BCR (3.78) was found in S1 obviously because of less total plant protection cost (Rs.12000 ha-1) incurred on management of fruit fly.The results of present studies on evaluation of methyl eugenol trap based eco-friendly management strategies against Bactrocera spp. in rainy season guava crop indicated that all the strategies were found better than untreated control. The strategy S2 (methyl eugenol traps+3 spray of NSKE 5%) was found best among all the strategies in all respect. The present findings are strongly in agreement with the studies conducted by Bhowmik et al. (2015); Shivendra and Singh (1998).