Alternate Bearing in Olive - A Review

Alternate bearing is a wide spread phenomenon in many fruit tree species and cause severe labour, marketing and economical problem.The term "alternate or biennial" bearing designate the production of a heavy fruit crop "On" year followed by a light fruit crop or trees may not bear a crop at all the next "Off" year.Alternate bearing is a widespread problem for growers of fruit trees, occurring in both evergreen and deciduous trees.It is more pronounced in old productive trees (more than 10 years) in comparison with the young productive trees (about 3-5 years).The domestic olive (Olea europaea) is genetically high alternating in fruit production.The degree of alternate bearing is highly dependent on the environmental conditions and might be very different in accordance with the climate in each growing region.The expression of alternate bearing involves a wide range of changes in activation and repression of endogenous metabolic pathway.The production of olive remains fluctuating over the years due to the problem of alternate bearing and thus the trade and consumption of the producer countries is affected.Horticultural treatments such as thinning, girdling, pruning and irrigation, can reduce the severity of biennial bearing This review article will help understanding the problem, its basic reasons and the possible management practices of the problem.