Release of Five Sweetpotato Cultivars in Uganda

Abstract

Origin 'Bwanjule', 'New Kawogo', 'Tanzania', and 'Wagabolige' are superior Ugandan farmers' cultivars selected from a collection of 380 landrace accessions assembled at Namulonge Agricultural and Animal Production Research Institute (NAARI) in 1987 and subsequently evaluated in trials at NAARI and elsewhere in Uganda. Pedigrees of these landrace cultivars are not known, but they are assumed to be chance seedlings selected by farmers. On the basis of numbers of landrace cultivars, and the adaptation of these cultivars to local conditions, including diseases and pests, eastern Africa is considered to be a secondary center of sweetpotato genetic diversity. 'Sowola', designated NIS/90/389a during testing, is a seedling selection from the sweetpotato breeding program at NAARI, and was selected from bulked seed from a polycross of 18 parents made from 1989 to 1990. The progenitors in this polycross block were popular farmers' cultivars from various parts of

Chemical basis for resistance in sweetpotato Ipomoea batatas to the sweetpotato weevil Cylas puncticollis

“…Fragmentation in APCI-MS (+) was characterized by the molecular ion of each compound with two fragments representing the cinnamate moiety (e.g., coumarate and coumaroyl). For example, the molecular ion for hexadecyl-p-coumaric acid (2) was m/z 389 [M + H] + which is in agreement with a molecular weight of 388, with fragments at m/z 165 (coumaric acid) and m/z 147 (coumaroyl) consistent with losses of C 16 H 33 and [O-C 16 H 33 ] + , respectively. The most abundant compounds in the latex of Tanzania were 2 and 4 with a small amount of 1 compared to New Kawogo (Fig.…”

“…Bioassay to evaluate feeding and oviposition by C. puncticollis on Tanzania and New Kawogo Farmers in Uganda consistently report that a sweetpotato variety, New Kawogo, suffers lower sweetpotato weevil damage by harvest time compared to a popular and commercially important variety, Tanzania, widely grown in sub-Saharan Africa [16]. Consequently, we used these two varieties to evaluate differences in feeding behavior and development of adults on sweetpotato roots and for subsequent chemical analysis to determine if any components could be associated with this apparent varietal resistance.…”

Improved Dry-Fleshed Sweetpotato Genotypes Resistant to Insect Pests

“…Control genotypes included eight dry-ßeshed cultivars: ÔGA90-16Õ (PI 612703) , USDA 2005, ÔHiDryÕ(PI 566633) , USDA 2005, ÔLibertyÕ (developed as W-341) , ÔPicaditoÕ (PI 634399) (OÕHair et al 1983, USDA 2005, ÔSumorÕ (PI 566657) , USDA 2005, ÔTanzaniaÕ (PI 595887) (Mwanga et al 2001, USDA 2005, ÔTinianÕ (PI 153655) (USDA 2005), and ÔWhite RegalÕ . Also included were three moist orange-ßeshed genotypes: ÔBeaure-gardÕ (PI 566613) (Rolston et al 1987, USDA 2005, ÔSC1149-19Õ (PI 63440) (USDA 2005), and ÔRegalÕ (PI 566650) , USDA 2005.…”

Effect of local inoculum on the spread of sweet potato virus disease: limited infection of susceptible cultivars following widespread cultivation of a resistant sweet potato cultivar

“…Foliar cuttings approximately 30 cm long (the normal planting material used in Uganda) of cvs Tanzania and Tororo 3 were obtained for the trial from symptomless plants growing at Namulonge Agricultural and Animal Production Research Institute (NAARI). Each on‐farm trial was planted with 100 cuttings of each of cvs Tanzania and Tororo 3, both of which are only moderately resistant to SPVD ( Mwanga et al ., 1995 ). At all sites, four cuttings of one or other cultivar were planted in mounds spaced approximately 1 m apart as typically done by Ugandan farmers, using a randomized complete block design of five replicates, each replicate comprising two plots, each planted with 20 cuttings of either cultivar.…”