2019 ASHS Annual Conference

Raspberry and blackberry are among most valuable crops in Coastal California, but evaluation of public varieties has been limited. Recent releases and selections from public breeding programs were tested in high tunnels at Santa Paula and Oceano, CA. We planted plugs of Kwanza, Kweli, Imara, PrimeArk (PA) 45 and PA Traveler in September 2016 and APF-268T, ORUS 4545-1, Vintage and Kokanee in April 2017. Each 8 by 3 ft plot had either four blackberry or six raspberry plants. During July-Dec of 2017 and May-Nov 2018 we harvested fruit at Santa Paula and from Jun to Dec at Oceano. At both locations, among raspberries planted in September 2016, Imara and Kweli were most productive during Jul-Oct 2017 harvest (with marketable yield 10-11 kg/plot) followed by Kwanza (6kg/plot). PrimeArk 45 blackberry yielded about 11 kg/plot followed by PA Traveler (~2 kg/plot). Fruit production during this period was <2 kg /plot for varieties planted in April 2017. Unmarketable fruit production followed the same trends, except for PA45 that had lesser fraction of unmarkable fruit than raspberries. On Oct 1, 2017 raspberries were either 1) cut back at 3 ft and defoliated leaving floricanes and allowing additional 25 primocanes per plot to develop, 2) same as 1 but floricanes removed 4 months later 3) mowed down to the ground and maintained at 25 primocanes per plot. Same management treatments were applied to blackberries in Jan 2018. In 2018 at Santa Paula all raspberries had similar yields (~4.5 kg/plot), greatly reduced by increased soil salinity and pH compared to 2017. However, blackberry yields in 2018 were greater than in 2017 and highest for PA45 (23kg/plot) followed by APF268T and ORUS4545-1 (10.5 kg and 7.8 kg/plot) and PA Traveler (6.5 kg/plot). All raspberries had greater yields in management treatment 1 compared to 2 and 3, while all blackberries yielded more under management 1 and 2 compared to 3 in 2018 at Santa Paula. Kwanza had largest fruit (5.5 g/berry) and Brix content among raspberries, and PA45 (8.3 g/berry) among blackberries. Blackberries had greater shelf life in cold storage than raspberries (among which Vintage was most susceptible to respiration related weight loss and decay).