Control of Cherry Leaf Spot and Cherry Fruit Fly at Sour Cherry

The investigations were made in the experimental sour cherry orchard from the Institute of Agriculture, Kyustendil, Bulgaria, during the period 2010-2014, in order to compare conventional and integrated sour cherry protection against cherry leaf spot and cherry fruit fly. Two variants were investigated, with two different treatment approaches for the control of cherry leaf spot and cherry fruit fly. Variant 1 – cherry leaf spot was controlled by protective treatments with dodin and tebuconazole + trifloxystrobin and cherry fruit fly was controlled by treatments with deltametrin and thiacloprid, independently of density. Variant 2 - cherry leaf spot was controlled by post-infection (curative) treatments with tebuconazole + trifloxystrobin and cherry fruit fly was controlled by treatments based on biological threshold: 10-11 cherry fruit fly females caught in traps up to the moment for chemical treatment. It was established that Blumeriella japii can be successfully controlled by post-infection treatments and by this the number of insecticide treatments was reduced. The treatments against cherry fruit fly can be avoided or reduced when the attack control is based on the biological threshold established in the studied area.


Introduction
The soil, climatic and topographical conditions in many region of Bulgaria are favorable for sour and sweet cherry cultivation, with proper conditions for the production of high quality fruits. Even so, it is impossible to have high quality and quantity production without plant protection practices. There are numerous fungi and pests that attack sour cherry, but cherry leaf spot caused by caused by Monilinia laxa and Monilinia laxa (Borovinova, 1998(Borovinova, , 2006Edson Gelvonauskien For the control of cherry leaf spot it is recommended to apply 4-7 treatment favourable weather conditions (Bielenin 2006; Holb et al can be reduced by post registration of infe Sredkov, 2006;Jones, 1981a, 1981b).
Cherry fruit fly ( sour cherry that might cause economically damages in orchards (Borovinova and Sredkov, 2006;Daniel, Grunder, 2012;Özdem and Kilinçer, 2009;Stamenkovi 2012). One or two treatments are necessary in order to control cherry fruit fly (Daniel and Grunder, 2012;Kovanci and Kovanci, 2006; Stamenkovi of R. cerasi based on economic threshold application is an effective method for reducing the number of insecticide treatments (Borovinova and Sredkov, 2006).
Sour cherry fruit need a short time to ripen and for a good quality is very important to pro Received: 08 Apr

Control of Cherry Leaf Spot and Cherry Fruit Fly at
The investigations were made in the experimental sour cherry orchard from the Institute of Agriculture, Kyustendil, Bulgaria, the period 2010-2014, in order to compare conventional and integrated sour cherry protection against cherry leaf spot and c Two variants were investigated, with two different treatment approaches for the control of cherry leaf spot and cherry fruit cherry leaf spot was controlled by protective treatments with dodin and tebuconazole + trifloxyst treatments with deltametrin and thiacloprid, independently of density. Variant 2 (curative) treatments with tebuconazole + trifloxystrobin and cherry fruit fly 11 cherry fruit fly females caught in traps up to the moment for chemical treatment. It was established that successfully controlled by post cherry fruit fly can be avoided or reduced when the attack control is based on the biological threshold establ

Blumeriella japii
The soil, climatic and topographical conditions in many region of Bulgaria are favorable for sour and sweet cherry cultivation, with proper conditions for the production of high quality fruits. Even so, it is impossible to have high quality and oduction without plant protection practices. There are numerous fungi and pests that attack sour cherry, but cherry leaf spot caused by Blumeriella jaapii Monilinia laxa, fruit rot caused by Monilinia laxa are the most important fungal diseases (Borovinova, 1998(Borovinova, , 2006Edson Gelvonauskienė et al., 2004;Holb, 2003Holb, , 2004Schuster, 2004).
For the control of cherry leaf spot it is recommended to apply 7 treatments during the growing season, in years with favourable weather conditions (Bielenin et al., 2010). The number of fungicide treatments can be reduced by post-infection (curative) treatments, after the registration of infection (Borovinova, 1998;Borovinova and Sredkov, 2006;Jones, 1981a, 1981b).
Cherry fruit fly (Rhagoletis cerasi sour cherry that might cause economically damages in orchards (Borovinova and Sredkov, 2006;Daniel, Grunder, 2012;Özdem and Kilinçer, 2009;Stamenkovi 2012). One or two treatments are necessary in order to control cherry fruit fly (Daniel and Grunder, 2012;Kovanci and Kovanci, 2006; Stamenković based on economic threshold application is an effective method for reducing the number of insecticide treatments (Borovinova and Sredkov, 2006).
Sour cherry fruit need a short time to ripen and for a good quality is very important to pro The investigations were made in the experimental sour cherry orchard from the Institute of Agriculture, Kyustendil, Bulgaria, 2014, in order to compare conventional and integrated sour cherry protection against cherry leaf spot and c Two variants were investigated, with two different treatment approaches for the control of cherry leaf spot and cherry fruit cherry leaf spot was controlled by protective treatments with dodin and tebuconazole + trifloxyst treatments with deltametrin and thiacloprid, independently of density. Variant 2 (curative) treatments with tebuconazole + trifloxystrobin and cherry fruit fly 11 cherry fruit fly females caught in traps up to the moment for chemical treatment. It was established that successfully controlled by post-infection treatments and by this the number of insecticide treatments was reduced. The treatments against cherry fruit fly can be avoided or reduced when the attack control is based on the biological threshold establ Blumeriella japii, control, fungal disease, pest, The soil, climatic and topographical conditions in many region of Bulgaria are favorable for sour and sweet cherry cultivation, with proper conditions for the production of high quality fruits. Even so, it is impossible to have high quality and oduction without plant protection practices. There are numerous fungi and pests that attack sour cherry, but cherry Blumeriella jaapii, blossom and twig blight fruit rot caused by are the most important fungal diseases (Borovinova, 1998(Borovinova, , 2006Edson et al., 1998;Feldmane, 2011;Holb, 2003Holb, , 2004Schuster, 2004). For the control of cherry leaf spot it is recommended to apply s during the growing season, in years with favourable weather conditions (Bielenin et al ., 2010). The number of fungicide treatments infection (curative) treatments, after the ction (Borovinova, 1998;Borovinova and Sredkov, 2006;Jones, 1981a, 1981b).
Rhagoletis cerasi L.) is an important pest of sour cherry that might cause economically damages in orchards (Borovinova and Sredkov, 2006;Daniel, Grunder, 2012;Özdem and Kilinçer, 2009;Stamenkovi 2012). One or two treatments are necessary in order to control cherry fruit fly (Daniel and Grunder, 2012;Kovanci and ć et al., 2012;Vasev, 1983). Con based on economic threshold application is an effective method for reducing the number of insecticide treatments (Borovinova and Sredkov, 2006).
Sour cherry fruit need a short time to ripen and for a good quality is very important to protect cherry fruit from pesticide The investigations were made in the experimental sour cherry orchard from the Institute of Agriculture, Kyustendil, Bulgaria, 2014, in order to compare conventional and integrated sour cherry protection against cherry leaf spot and c Two variants were investigated, with two different treatment approaches for the control of cherry leaf spot and cherry fruit cherry leaf spot was controlled by protective treatments with dodin and tebuconazole + trifloxyst treatments with deltametrin and thiacloprid, independently of density. Variant 2 (curative) treatments with tebuconazole + trifloxystrobin and cherry fruit fly 11 cherry fruit fly females caught in traps up to the moment for chemical treatment. It was established that infection treatments and by this the number of insecticide treatments was reduced. The treatments against cherry fruit fly can be avoided or reduced when the attack control is based on the biological threshold establ , control, fungal disease, pest, The soil, climatic and topographical conditions in many region of Bulgaria are favorable for sour and sweet cherry cultivation, with proper conditions for the production of high quality fruits. Even so, it is impossible to have high quality and oduction without plant protection practices. There are numerous fungi and pests that attack sour cherry, but cherry , blossom and twig blight fruit rot caused by Monilinia fructigena are the most important fungal diseases ., 1998; Feldmane, 2011;Holb, 2003Holb, , 2004Schuster, 2004). For the control of cherry leaf spot it is recommended to apply s during the growing season, in years with et al., 1991;Borovinova, ., 2010). The number of fungicide treatments infection (curative) treatments, after the ction (Borovinova, 1998;Borovinova and Sredkov, 2006;Jones, 1981a, 1981b).
L.) is an important pest of sour cherry that might cause economically damages in orchards (Borovinova and Sredkov, 2006;Daniel, 2014;Daniel and Grunder, 2012;Özdem and Kilinçer, 2009;Stamenković 2012). One or two treatments are necessary in order to control cherry fruit fly (Daniel and Grunder, 2012;Kovanci and ., 2012;Vasev, 1983). Con based on economic threshold application is an effective method for reducing the number of insecticide treatments (Borovinova and Sredkov, 2006).
Sour cherry fruit need a short time to ripen and for a good tect cherry fruit from pesticide The investigations were made in the experimental sour cherry orchard from the Institute of Agriculture, Kyustendil, Bulgaria, 2014, in order to compare conventional and integrated sour cherry protection against cherry leaf spot and c Two variants were investigated, with two different treatment approaches for the control of cherry leaf spot and cherry fruit cherry leaf spot was controlled by protective treatments with dodin and tebuconazole + trifloxyst treatments with deltametrin and thiacloprid, independently of density. Variant 2 (curative) treatments with tebuconazole + trifloxystrobin and cherry fruit fly 11 cherry fruit fly females caught in traps up to the moment for chemical treatment. It was established that infection treatments and by this the number of insecticide treatments was reduced. The treatments against cherry fruit fly can be avoided or reduced when the attack control is based on the biological threshold establ , control, fungal disease, pest, Rhagoletis cerasi The soil, climatic and topographical conditions in many region of Bulgaria are favorable for sour and sweet cherry cultivation, with proper conditions for the production of high quality fruits. Even so, it is impossible to have high quality and oduction without plant protection practices. There are numerous fungi and pests that attack sour cherry, but cherry , blossom and twig blight Monilinia fructigena are the most important fungal diseases ., 1998; Feldmane, 2011;Holb, 2003Holb, , 2004Schuster, 2004). For the control of cherry leaf spot it is recommended to apply s during the growing season, in years with ., 1991; Borovinova, ., 2010). The number of fungicide treatments infection (curative) treatments, after the ction (Borovinova, 1998;Borovinova and L.) is an important pest of sour cherry that might cause economically damages in orchards 2014; Daniel and ć et al., 2012). One or two treatments are necessary in order to control cherry fruit fly (Daniel and Grunder, 2012;Kovanci and ., 2012;Vasev, 1983). Control based on economic threshold application is an effective method for reducing the number of insecticide Sour cherry fruit need a short time to ripen and for a good tect cherry fruit from pesticide residues. Application of post cherry leaf spot and economic threshold for the control of cerasi insecticide treatments (Borovinova and other hand, the use of yellow sticky traps, crop netting, foliar applications of Naturalis organic cherry production ( 2014). The aim of this investigation wa and integrated sour cherry protection against cherry leaf spot and cherry fruit fly.

Materials and methods
The investigations were made at the experimental sour cherry orchard of the Institute of Agriculture Bulgar was crafted on rootstocks Two variants were investigated, with different treatments schemes. Variant 1 (V1) protective trifloxystrobin, while cherry fruit fly was controlled by treatments with deltametrin and thiacloprid, independently of density. Variant 2 (V2) (curative) treatmen and Jones (1981aJones ( , 1981b with tebuconazole + trifloxystrobin and cherry fruit fly was controlled by treatments based on biological threshold: 10 traps up to the moment for ch with pyrethrum. Yellow sticky "Rebel" traps were used for monitoring of cherry fruit fly. The investigations were made in the experimental sour cherry orchard from the Institute of Agriculture, Kyustendil, Bulgaria, 2014, in order to compare conventional and integrated sour cherry protection against cherry leaf spot and c Two variants were investigated, with two different treatment approaches for the control of cherry leaf spot and cherry fruit cherry leaf spot was controlled by protective treatments with dodin and tebuconazole + trifloxyst treatments with deltametrin and thiacloprid, independently of density. Variant 2 -cherry leaf spot was controlled by post (curative) treatments with tebuconazole + trifloxystrobin and cherry fruit fly was controlled by treatments based on biological threshold: 11 cherry fruit fly females caught in traps up to the moment for chemical treatment. It was established that infection treatments and by this the number of insecticide treatments was reduced. The treatments against cherry fruit fly can be avoided or reduced when the attack control is based on the biological threshold establ residues. Application of post cherry leaf spot and economic threshold for the control of cerasi are effective methods for reducing the number of insecticide treatments (Borovinova and other hand, the use of yellow sticky traps, crop netting, foliar applications of Naturalis organic cherry production ( 2014).
The aim of this investigation wa and integrated sour cherry protection against cherry leaf spot and cherry fruit fly.

Materials and methods
The investigations were made at the experimental sour cherry orchard of the Institute of Agriculture Bulgaria, during the period 2010 was crafted on rootstocks Two variants were investigated, with different treatments schemes. Variant 1 (V1) protective treatments with dodin and tebuconazole + trifloxystrobin, while cherry fruit fly was controlled by treatments with deltametrin and thiacloprid, independently of density. Variant 2 (V2) -cherry leaf spot was controlled by post (curative) treatmen and Jones (1981aJones ( , 1981b with tebuconazole + trifloxystrobin and cherry fruit fly was controlled by treatments based on biological threshold: 10 traps up to the moment for ch with pyrethrum. Yellow sticky "Rebel" traps were used for monitoring of cherry fruit fly.

Control of Cherry Leaf Spot and Cherry Fruit Fly at Sour Cherry
Maria BOROVINOVA*, Vilina PETROVA corresponding author) The investigations were made in the experimental sour cherry orchard from the Institute of Agriculture, Kyustendil, Bulgaria, 2014, in order to compare conventional and integrated sour cherry protection against cherry leaf spot and c Two variants were investigated, with two different treatment approaches for the control of cherry leaf spot and cherry fruit cherry leaf spot was controlled by protective treatments with dodin and tebuconazole + trifloxystrobin and cherry fruit fly was controlled by cherry leaf spot was controlled by post was controlled by treatments based on biological threshold: 11 cherry fruit fly females caught in traps up to the moment for chemical treatment. It was established that infection treatments and by this the number of insecticide treatments was reduced. The treatments against cherry fruit fly can be avoided or reduced when the attack control is based on the biological threshold established in the studied area.
, treatments www.notulaebiologicae.ro residues. Application of post-infection (curative) treatments for cherry leaf spot and economic threshold for the control of are effective methods for reducing the number of insecticide treatments (Borovinova and other hand, the use of yellow sticky traps, crop netting, foliar applications of Naturalis-L (B. bassiana organic cherry production (Daniel and Grunder, 2012; The aim of this investigation wa and integrated sour cherry protection against cherry leaf spot and

Materials and methods
The investigations were made at the experimental sour cherry orchard of the Institute of Agriculture ia, during the period 2010-2014. Cultivar 'Erdi Bötermo' was crafted on rootstocks Mahaleb 'IK M9' Two variants were investigated, with different treatments schemes. Variant 1 (V1) -cherry leaf spot was controlled by treatments with dodin and tebuconazole + trifloxystrobin, while cherry fruit fly was controlled by treatments with deltametrin and thiacloprid, independently of density. cherry leaf spot was controlled by post (curative) treatments according to the method of Jones (1981a, 1981b) with tebuconazole + trifloxystrobin and cherry fruit fly was controlled by treatments based on biological threshold: 10-11 females of cherry fruit fly caught in traps up to the moment for chemical treatment (Sredkov, 2000) with pyrethrum. Yellow sticky "Rebel" traps were used for monitoring of cherry fruit fly.

Sour Cherry
The investigations were made in the experimental sour cherry orchard from the Institute of Agriculture, Kyustendil, Bulgaria, 2014, in order to compare conventional and integrated sour cherry protection against cherry leaf spot and c Two variants were investigated, with two different treatment approaches for the control of cherry leaf spot and cherry fruit robin and cherry fruit fly was controlled by cherry leaf spot was controlled by post was controlled by treatments based on biological threshold: 11 cherry fruit fly females caught in traps up to the moment for chemical treatment. It was established that Blumeriella japii infection treatments and by this the number of insecticide treatments was reduced. The treatments against ished in the studied area.
infection (curative) treatments for cherry leaf spot and economic threshold for the control of are effective methods for reducing the number of insecticide treatments (Borovinova and Sredkov, 2006). On the other hand, the use of yellow sticky traps, crop netting, foliar B. bassiana) are most suitable for the Daniel and Grunder, 2012; The aim of this investigation was to compare conventional and integrated sour cherry protection against cherry leaf spot and The investigations were made at the experimental sour cherry orchard of the Institute of Agriculture 2014. Cultivar 'Erdi Bötermo' Mahaleb 'IK M9' and planted in 2006. Two variants were investigated, with different treatments cherry leaf spot was controlled by treatments with dodin and tebuconazole + trifloxystrobin, while cherry fruit fly was controlled by treatments with deltametrin and thiacloprid, independently of density. cherry leaf spot was controlled by post ts according to the method of Jones (1981a, 1981b) with tebuconazole + trifloxystrobin and cherry fruit fly was controlled by treatments based on 11 females of cherry fruit fly caught in emical treatment (Sredkov, 2000) with pyrethrum. Yellow sticky "Rebel" traps were used for

Sour Cherry
The investigations were made in the experimental sour cherry orchard from the Institute of Agriculture, Kyustendil, Bulgaria, during 2014, in order to compare conventional and integrated sour cherry protection against cherry leaf spot and cherry fruit fly. Two variants were investigated, with two different treatment approaches for the control of cherry leaf spot and cherry fruit fly. Variant 1robin and cherry fruit fly was controlled by cherry leaf spot was controlled by post-infection was controlled by treatments based on biological threshold: Blumeriella japii can be infection treatments and by this the number of insecticide treatments was reduced. The treatments against ished in the studied area.
infection (curative) treatments for cherry leaf spot and economic threshold for the control of R.
are effective methods for reducing the number of Sredkov, 2006). On the other hand, the use of yellow sticky traps, crop netting, foliar ) are most suitable for the Daniel and Grunder, 2012;Daniel, s to compare conventional and integrated sour cherry protection against cherry leaf spot and The investigations were made at the experimental sour cherry orchard of the Institute of Agriculture -Kyustendil, 2014. Cultivar 'Erdi Bötermo' and planted in 2006. Two variants were investigated, with different treatments cherry leaf spot was controlled by treatments with dodin and tebuconazole + trifloxystrobin, while cherry fruit fly was controlled by treatments with deltametrin and thiacloprid, independently of density. cherry leaf spot was controlled by post-infection ts according to the method of Jones (1981a, 1981b) with tebuconazole + trifloxystrobin and cherry fruit fly was controlled by treatments based on 11 females of cherry fruit fly caught in emical treatment (Sredkov, 2000) with pyrethrum. Yellow sticky "Rebel" traps were used for can be infection treatments and by this the number of insecticide treatments was reduced. The treatments against infection (curative) treatments for R. are effective methods for reducing the number of Sredkov, 2006). On the other hand, the use of yellow sticky traps, crop netting, foliar ) are most suitable for the Daniel, s to compare conventional and integrated sour cherry protection against cherry leaf spot and The investigations were made at the experimental sour Kyustendil, 2014. Cultivar 'Erdi Bötermo' and planted in 2006. Two variants were investigated, with different treatments cherry leaf spot was controlled by treatments with dodin and tebuconazole + trifloxystrobin, while cherry fruit fly was controlled by treatments with deltametrin and thiacloprid, independently of density. infection ts according to the method of Jones (1981a, 1981b) with tebuconazole + trifloxystrobin and cherry fruit fly was controlled by treatments based on 11 females of cherry fruit fly caught in emical treatment (Sredkov, 2000) with pyrethrum. Yellow sticky "Rebel" traps were used for For both variants, bacterial canker, brown rot and shot hole were controlled by protective treatments with copper fungicides during late autumn and early spring and 2 treatments with cyprodinil and tebuconazole during bloom period, each year of the study.
Five trees of each variant were estimated for cherry leaf spot, taking an average sample of 250 leaves from the four cardinal sides of each tree, at the end of August. The percentage of infected leaf area was estimated according to the scale of Townsend and Heuberger (Kremer and Unterstenhofer, 1967). The data for the rate (incidence) of attack of leaves by cherry leaf spot were statistically processed by analysis of variance (Maneva, 2007).
Samples of 300 fruits from the four cardinal sides of five trees of each variant during harvest were estimated for cherry fruit fly damage. Data were expressed as means, based on values noted during each year of experiment.

Results and discussions
Climatic conditions, especially the duration of wetting periods of sour cherry leaves and air temperature, were favourable for development of cherry leaf spot during all years of investigation. There were registered 3 wetting periods with heavy infection in 2012 (minimum) and 16 such periods during 2014 (maximum) ( Table 1). Dependent on the wetting periods, associated with heavy infection, there were made during the study interval minimum 2 and maximum 4 post-infection treatments, per year (Table 1).
All treatments in 2012, 2013 and 2014 were applied prior to harvest, while in 2010 and 2011 two were before and one was postharvest. The post-infection treatments were efficient. The disease incidence (rate of attack of the leaves) was from very low, as it ranged between 5.76 in 2012 and to 11.76% in 2014 ( Table  2). The reason of the comparatively higher rate of attack in 2012 might be due to daily rainfalls, which interfered with the application of post-infection treatments on time.
Cherry trees selected for Variant 1 were protected from B. jaapii by 3 or 4 fungicide treatments. Applications started at the stage of petal fall, followed at 10-14 day intervals to harvest and one or two were postharvest treatments. Simultaneously, the preventive treatments were effective. The rate of attack of the leaves was low, with one exception in 2010 ( Table 2).
The present results demonstrated that Blumeriella japii can be controlled successfully by preventive and post-infection (curative) treatments. The differences between disease incidence (rate of attack on leaves) at Variant 1 and Variant 2 were not significant during the period of investigation with the exception of year 2010 when the rate of attack on leaves of Variant 1 was comparatively higher than for Variant 2, 30.35 and 7.17 respectively (Table 2).
Preventive treatments schedule gave effective control of cherry leaf spot and was in agreement with the results of previous studies conducted by Velitschkova (1983), who established that cherry leaf spot can be controlled successfully with 4 or 5 preventive treatments. Only in 2013 one treatment was reduced at Variant 2. Nevertheless of the decrease treatment, the cherry leaf spot infection was unimportant and only separate spots were found. That confirmed the results published by Borovinova (1994), established at sour cherry cultivar 'Schatten Morelle' in Kyustendil, when application of post-infection treatments was reduced to two treatments and still provided a good protection. The data of Eisensmith and Jones (1981a, b) about the control of cherry leaf spot of sour cherry in USA, Michigan were similar.
During the period of investigation the density of cherry fruit fly increased every year. The average number of caught flies at the two variants was minimum 5 flies per trap (V1, 2010) and maximum 314 in 2013 also for V1 (Table 3). The number of females surpassed vastly the number of male flies. Independently of the density of females of cherry fruit fly at Variant 1, there were applied 1 treatment during 2011, 2014 and 2 treatments during 2012 and 2013. The rate of wormy fruits/damaged was 1.33% in 2013, and as low as 0 in 2010 and 2014 respectively ( Table 3).
The density of cherry fruit fly females caught in traps during 2010, 2011, 2013 were less than the biological threshold up to the scheduled moment for chemical treatment and therefore cherry trees in Variant 2 (integrated treatments) were not treated. During harvesting, no wormy fruits were found in 2010 and 2011, while the rate of wormy fruits was 2% in 2013. Only during 2014 the density of females of cherry fruit fly surpass biological threshold and therefore one treatment was applied.  Heavy  2010  19  5  5  9  3  4  2011  16  7  5  4  3  3  2012  20  7  10  3  4  4  2013  19  8  7  4  3  2  2014  27  8  3  16  3 3 V1-conventional (with protective treatments) V2-integrated (with post-infection treatments)  Cherry fruits were protected and the percent of wormy fruits was 0.67% (Table 3).

Conclusions
The pesticide applications at sour cherry can be reduced by post-infection (curative) treatments against cherry leaf spot and when control of cherry fruit fly is based on the biological threshold (10-11 females of cherry fruit fly caught in traps up to the moment for chemical treatment).