Taro [Colocasia esculenta (L.) Schott] corms from 57 vegetatively propagated cultivars were evaluated for yield, physical and chemical characteristics, and either microwaved, microwaved and ground into poi, or fried. Poi color ranged from purple to orange or yellow and the dry matter content from 18.3 to 48%. The taste panel preferred poi made from a number of other cultivars than that made from the most common cultivar `Lehua Maoli' used in Hawaii, and a darker bluish-red poi was preferred. Corm total soluble solids were positively correlated to corm specific gravity and dry matter, and to the taste preference of microwaved corm and poi. The fried cultivars varied widely in yield and corm color varied from cream to white. Additionally, some cultivars did not have purple vascular bundles, and others were acrid after frying. Chip oil content was negatively correlated to corm weight, dry weight, and chip yield. The `Bin Liang' cultivar was judged the best overall in fried chip taste. Considerable variation in corm yield and quality characteristics existed in this widely cultivated vegetatively propagated tropical crop.

Several products acceptable for organically-certified produce were evaluated in the field for their ability to control root-knot nematode, Meloidogyne javanica, in tropical cropping systems. In the first evaluation, tomato yield and nematode reproduction were recorded in plots treated with Nematrol (a ground sesame product) at 129, 256, 516, or 774 kg/ha (115, 230, 460, and 690 lb/ac); composted chicken manure at 11.2 or 22.4 T/ha (5 or 10 ton/ac); or blood meal at 8.3 or 12 T/ha (2.7 or 5.4 ton/ac). Plots treated with fenamiphos (7 or 14 g a.i./m row; 0.08 or 0.15 oz/ft) or left untreated were included as controls. Tomato yield was greatest in the 14 g (0.15 oz) a.i. fenamiphos-treated plots and lowest in the untreated plots. Nematrol at all rates gave better control than the untreated. Blood meal at the high rate may have been Brent S. Sipes is Associate Professor, and Donald P. Schmitt is Professor, Department of Plant Pathology, University of Hawaii, Honolulu, HI 96822. Alton S. Arakaki is Specialist, Cooperative Extension Service, Hoolehua, Molokai, HI 96729. Randall T. Hamasaki is Associate Specialist,

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Twelve sweetpotato (Ipomoea batatas var. batatas) accessions/cultivars/landraces (entries) were evaluated for yield, resistance to pests, and quality in five field trials planted at Pepe`ekeo, Hawai‘i Island, and replicated over time with blocks planted on May and Oct. 2014, Feb. and July 2015, and Jan. 2016. Plots were harvested at 4.5 to 6 months after planting. In the first two field trials, local entries planted were ‘Okinawan’, ‘Mokuau’, and ‘Kona B’, as well as PI 531094, ‘Beauregard’, PI 573309, PI 573330, ‘Darby’, ‘Pelican Processor’, and ‘Picadito’. Yields of ‘Mokuau’ and ‘Kona B’ were low and were replaced in the latter three field trials with ‘Murasaki-29’ and ‘LA 08-21p’ from Louisiana State University (LSU) AgCenter, Baton Rouge. At harvest, storage roots were graded according to State of Hawai‘i standards and marketable yields included grades AA, A, and B. Then, injuries of storage roots due to infestations of sweetpotato weevil (Cylas formicarius elegantulus) in each category were estimated. Finally, sugar concentrations, anthocyanins, and β-carotene contents were measured in storage roots. Marketable fresh weight yields of entries differed significantly, with ‘LA 08-21p’ having the greatest marketable yield. However, ‘LA 08-21p’ also had the greatest incidence of damage due to sweetpotato weevil, perhaps because of its growth habit as a tight cluster of storage roots located close to the soil surface. Entries also had significantly different sugar concentrations (fructose, glucose, sucrose, maltose, and total sugars). Concentrations of sucrose ranged from 25 to 68 mg·g−1 fresh weight and were greater than those of monosaccharides analyzed. ‘Beauregard’ had the highest sucrose concentration and total sugars. Purple-fleshed cultivars Okinawan and LA 08-21p contained total monomeric anthocyanins that ranged from 34 to 37 mg/100 g dry weight. Orange-fleshed cultivars Beauregard and Darby contained β-carotene that ranged from 5485 to 8302 µg/100 g fresh weight. These results provide yields of storage roots, susceptibility to sweetpotato weevils, and amounts of antioxidants in purple- and orange-fleshed sweetpotato cultivars to growers interested in producing new sweetpotato cultivars.