Prospects for the prevention in the field and the in post harvest of brown rot and lenticell rot

Transcription

1 Marta Mari CRIOF Gianni Ceredi - Apofruit Italia Prospects for the prevention in the field and the in post harvest of brown rot and lenticell rot Workshop november 2014 University of Zagreb Faculty of Agriculture The most important pathogens Monilinia fructigena: particularly aggressive on pome fruit but also on stone fruit Monilinia laxa: affects flowers, shoots, fruits especially stone fruit but also on pome fruit and other Rosaceae Monilinia fructicola: recently introduced in Italy but already widely Botrytis cinerea Rhizopus nigricans Penicillium expansum 1

2 Monilinia laxa Brown rot Monilinia fructigena Monilinia fructicola M. laxa M. fructigena M. fructicola Factors affecting the severity of infections of Monilinia spp Temperature Relative humidity Hours of wetting Rain Influence the number of biological cycles that take place in the growing season Conidia reach the fruit and can cause rot when there are favorable conditions or remain in a latent stage when weather conditions are unfavorable Conidia remain viable on the surface of the fruit also for 20 days with relatively low temperatures and high relative humidity 2

3 Cfu (n ) Diametro della colonia (mm) Growth of Monilinia spp at different temperatures (after 7 days) M. fructicola M.laxa M. fructigena C 5 C 10 C 15 C 20 C 25 C C 40 C Germination of conidia of Monilinia spp at different temperatures (after 20 days) M. fructicola M. laxa M. fructigena C 2 C 5 C 3

4 The development of rots and the economic damage Produzione Stoccaggio-Lavorazioneconfezionamento Trasporto Rivendita Protection and prophylaxis Post-harvest management Chemical protection Weather conditions Agricultural practices Varietal susceptibility 4

5 Varietal susceptibility It has a genetic basis There isn t any interest for the breeders about resistant cultivars It must be known and managed by agricultural producers Agricultural practices Pruning Nitrogen nutrition Vegetation luxuriance Orientation and arrangement of rows Excessive irrigation (close to the ripening) 28 farm monitored THESIS COMPARED % of fruit rot * Chemical protection Control Chemical Pruning Control Green pruning Soil management Plowed Grassed Irrigation Control Irrigation 49 a 12 b *** N.S N.S. 10 b 34 a *** N.S. = not significant ; *** = significant at 0,1%; * = after 7 days of shelf-life at 20 C. 5

6 Weather conditions Average temperatures for the period 21/06 /08 Tesi Total fruit harvested in 7 tests Total fruit with monilia infections after 7 days of shelf life Average percentage of infected fruits after 7 days of shelf life Check Check Chemical protection Classification FRAC Fungicides Resistance Action Committee Common name Cod. frac Cyprodinil 9 Fludioxonil 12 Tebuconazolo Fenbuconazolo Difenoconazolo Ciproconazolo 3 Mode of action Aminoacids synthesis Signal trasduction Biosynthesis of sterols in the cells membranes group A-P fungicides Anilino-Pyrimidines P-P fungicides PhenylPyrroles DMI fungicides DeMethylation Inhibitors Chemical group Anilino-pyrimidines Phenylpyrroles Triazoles Resistance risk medum low-medium medium Fenhexamid 17 Hydroxyanilides Hydroxyanilides low-medium Boscalid 7 Pyraclostrobin Trifloxystrobin 11 Respiration Carboxamides Pyridinecarboxamides medium QOI fungicides Quinone Outside Inhibitors Methoxy carbamats high 6

7 Risk of infection by Monilinia spp in the field : Flowering Fruit set Hardening core Ripening Evaluation of fungicides effectiveness Period: Field trials : 40 Farm involved: 25 Cv involved: 18 Experimental design: 1) Plots repeated in randomized block (27 tests) 2) Large plots without repetition(13 tests) Experimental design: Performing two fungicide treatments carried out at 14 and 7 days from harvesting Taking samples of fruits in correspondence with the first two harvests Conservation of the fruits in cold store (2 C) for 7 days) Placement of the samples of fruits in thermostated cell (18 C) for the shelf life checks (3 and 7 days) 7

8 Tebuconazole efficacy Testimone Control Tebuconazolo Average efficiency: 72.9 % , % 50 44, ,5,3 23,923,8 25,55 22,6 19,64 20,6 18,4 14,42 13, ,5 12,1 12,35 9,71 9,2 10,7 11,4 9,4 9,8 8,62 6,3 6,45 4,46 4,3 4,3 7,07 6,8 5 5,3 4,05 2,65 2,3 1,07 2,86 0, % n. prove Efficacy of boscalid+piraclostrobin: 100 Testimone Control Boscalid-Pyraclostrobin Average efficiency: 80.2 % % , ,8 23,6 22,77 21,9 16,5 16,8 17,1 15,1 15,2 14,8 12,8 12,5 9,9 10,9 12,5 10,7 8,7 9,8 3,89 5, ,97 5,88 3,59 4,3 2,9 3,9 0,36 1,44 1, n. prove 10.4% 8

9 Comparative efficacy of different active ingredients : Control incidence rot 100 Grado Leveldi of efficacia efficacy Incidenza di frutti marci nel testimone ,9 62,1 65,1 55,6 49,3 80, The prevention of brown rot damage due to Monilinia spp. involves the cultivation phase and post-harvest management of the product Therefore are interested in: Growers Agricoltural practices Variety choice Chemical prophylaxis Choice of fungicides and application strategies Storage house operators Hygiene of packaging and processing lines Adequate storage periods Adequate storage conditions (T -UR) 9

10 Control strategies in the prevention of Neofabrea alba infections on apple Sexual form: Neofabraea alba = Pezicula alba (old name) Asexual f.: Phlyctema vagabunda = Phlyctaena vagabunda = Trichoseptoria fructigena called (past) «Gloeosporium album» Marta Mari Università di Bologna Gianni Ceredi Apofruit Italia Neofabraea alba : symptoms 10

11 Neofabraea alba pycnidia Conidia of Phlyctema vagabunda Fruit infection process N. alba is present in cancers or cracks in the bark The contamination occurs through rains and / or run-off Incidence of the disease appears to be influenced by the shape and structure of lenticels (cv susceptibility) and their receptivity (maturity of the fruits) The stage after the contamination corresponds to germination of spores in the lenticels and the beginning of a long period of quiescence / latency From G. Bompeix (pers. comm.) 11

12 Potential source of inoculum How to evaluate the infection risk in orchard? Rain Quantity or duration (n. of rainy days) Leaf wetness associated with a rain event Minimum 4-5 hours!? Incidence of temperature!? Cumulative degree-hour during leaf wetness Incidence of maturity of fruits!? Susceptibility of varieties Modelisation is a possibility? 12

13 How to evaluate the infection risk in orchard? There are several factors that make not simple the chemical defense against N. Alba: The sources of primary inoculum are undetectable The inoculum is not easily monitored Factors affecting the relationship between the inoculum and the receptivity of the fruit are not completely known Remarks Raise awareness of the problem with the growers More attention on the agronomic practices Planning fungicide treatments Planning the harvest and not prolong it excessively Managing the product in packinghouse anticipating the commercialization of the product at greater risk Managing the fruit in storage house - Treatment with 1-mcp Managing the fruit in storage house - Thermotherapy 13