Alternate bearing is a problematic phenomenon that occurs in certain fruit and nut trees. It is characterized by trees flowering profusely and producing an excess amount of fruit in one season, called an “on” season, followed by the production of a
Alternate bearing (alternating years with high and low yields) is a prominent characteristic of ‘Kerman’ Pistacia vera L., the primary California cultivar ( California Pistachio Commission, 2006 ; Monselise and Goldschmidt, 1982 ). Generally
Alternate bearing is a major economic problem for producers of pecan nuts [Carya illinoinensis (Wangenh.) K. Koch], yet a fundamental understanding of alternate bearing remains elusive. Nut yields (over a period of up to 78 years) from a commercial-like orchard of 66 cultivars was used to calculate alternate bearing intensity (I). Best-fit regression analysis indicates no association between I and fruit ripening date (FRD) or nut volume; although, there was moderate association with post-ripening foliation periods (PRFP) in that I tends to decrease as the length of the PRFP decreases. Multiple regression models indicated that FRD and nut volume were poor predictors of I: however, PRFP possessed significant inverse predictive power. Late-season canopy health, as measured by percentage of leaflet retention, decreased as FRD approached early-season ripening. Late-season photoassimilation rate was high er on foliage of trees with late FRDs than those with mid- or early-season ripening dates. These data provide new insight into the complex nature of alternate bearing in pecan and provide evidence for modifying the existing theories of alternate bearing of pecan.
Alternate bearing is the most significant horticultural problem facing pecan producers. Studies have suggested that stored carbohydrate concentrations during the winter markedly affected subsequent flowering ( Malstrom, 1974 ; Smith and Waugh
excessive. Clearly, a strategy to reduce the abscission of reproductive structures would increase avocado yield. The reproductive phenology of many avocado cultivars, including ‘Hass’, is further characterized by alternate bearing. Alternate bearing is a
Alternate bearing (AB) poses a major challenge for the pecan [ Carya illinoinensis (Wangenh.) K. Koch.] industry ( Wood, 2003 ). AB refers to a tendency for wide season-to-season fluctuations in cropping intensity. This is often expressed as a
Alternate bearing (also called biennial or uneven bearing) is the tendency of a fruit tree to produce a heavy crop (on-crop year) followed by a light crop or no crop (off-crop year). The phenomenon is widespread, occurring in deciduous and
The Coastal Plain Experiment Station has been evaluating pecan [Carya illinoinensis (Wangenh.) K. Koch] cultivars for over 75 years. Using annual yield data from this program, the alternate bearing intensities (I) of 66 pecan cultivars and numbered U.S. Dept. of Agriculture (USDA) selections were determined. Values ranged from 0.19 to 0.93 in young trees, and from 0.27 to 0.91 in mature trees under high-input production practices. The adoption of fungicides, insecticides, and irrigation during the last 30 years has reduced the average I value from 0.70 to 0.55. I was negatively correlated with both nut yield and nut weight. All but one cultivar recommended for commercial production in Georgia have I values lower than the average of 0.57 for all cultivars in this test. Values calculated early in a tree's productive life cycle were highly correlated with those of mature trees.
Alternate bearing (AB) is the most important horticultural problem for the pecan ( Carya illinoinensis ) industry ( Wood, 2003 ). Alternate bearing in perennial tree crops comprises a propensity for “on” years of high fruit yield interspersed with
( Monselise and Goldschmidt, 1982 ). The alternate bearing cycle continues in subsequent seasons—seasons of heavy fruiting are referred to as “on” years, whereas seasons of low fruit numbers are called “off” years ( Monselise and Goldschmidt, 1982 ). Factors