The almond (Prunus dulcis) is a self-incompatible species that requires various orchard management techniques to encourage pollination and achieve a good fruit set. Fungicides are commonly applied to almond flowers ...The almond (Prunus dulcis) is a self-incompatible species that requires various orchard management techniques to encourage pollination and achieve a good fruit set. Fungicides are commonly applied to almond flowers to control fungaI infections, such as "blossom blight" and 'brown rot" that damage the flowers and developing fruits. However there is evidence that the application of some of these products may adversely affect pollination and fruit set. The effects of the fungicides captan, chlorothalonyl, propiconazole, mancozeb and dichloran on fruit set were studied in an orchard using "Nonpareil" and "Carmel" almond trees. The effects on in vitro pollen germination and pollen tube elongation were studied using "Carmel" pollen. With respect to Non Pareil fruit set, all fungicidal treatments were statistically similar to the control (11.5%) but being propiconazole (13.1%) and chlorotalonil (5.6%) different between them. Fruit set for "Carmel" was significantly lower than the control (26.1%) with all fungicidal treatments. After 24 hours, in vitro "Carmel" pollen germination was significantly higher in the control (90.5%) compared with the fungicidal treatments, with the exception of chlorothalonyl (70.2%). Pollen tube growth in the control was four times greater than in the fungicide treatments at 24 hours, none of which were significantly different from the other treatments. It can be concluded that the application of certain fungicides has a clearly detrimental effect on fruit set in "Nonpareil" and "Carmel" almond trees and on "Carmel" pollen activity.展开更多
文摘The almond (Prunus dulcis) is a self-incompatible species that requires various orchard management techniques to encourage pollination and achieve a good fruit set. Fungicides are commonly applied to almond flowers to control fungaI infections, such as "blossom blight" and 'brown rot" that damage the flowers and developing fruits. However there is evidence that the application of some of these products may adversely affect pollination and fruit set. The effects of the fungicides captan, chlorothalonyl, propiconazole, mancozeb and dichloran on fruit set were studied in an orchard using "Nonpareil" and "Carmel" almond trees. The effects on in vitro pollen germination and pollen tube elongation were studied using "Carmel" pollen. With respect to Non Pareil fruit set, all fungicidal treatments were statistically similar to the control (11.5%) but being propiconazole (13.1%) and chlorotalonil (5.6%) different between them. Fruit set for "Carmel" was significantly lower than the control (26.1%) with all fungicidal treatments. After 24 hours, in vitro "Carmel" pollen germination was significantly higher in the control (90.5%) compared with the fungicidal treatments, with the exception of chlorothalonyl (70.2%). Pollen tube growth in the control was four times greater than in the fungicide treatments at 24 hours, none of which were significantly different from the other treatments. It can be concluded that the application of certain fungicides has a clearly detrimental effect on fruit set in "Nonpareil" and "Carmel" almond trees and on "Carmel" pollen activity.