Supplemental pollination of jojoba - A means to increase yields

Jojoba (Simmondsia chinensis (Link) Schneider) is a perennial evergreen shrub native to the Sonoran Desert of the southwestern U.S. and northwestern Mexico. Jojoba is dioecious, with male and female flowers present in separate plants, and is wind pollinated. Possibly, much of the yield variation detected in commercial fields is due to pollination problems. Supplemental, mechanically applied pollen is an alternative that could improve fruit set, and hence increase yield. Pollen was mechanically collected in Catamarca Argentina and applied in Arizona during bloom in 2003 and 2004. The flower set was very good for both treated and untreated plants, and supplemental pollen did not consistently provide significant increases in the number or percentage of flowers pollinated. These results were presumably due to sufficient pollen in the test fields coming from pollinator rows of male plants. Weather condition at the time of pollen harvest strongly influenced pollen quality. Low pollen viability was observed when pollen was harvested following a two-day period with hot, dry winds. This indicates that pollen collection must be timed appropriately for sufficient viable pollen to be available for supplemental use. (C) 2006 Elsevier B.V. All rights reserved.