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  • Author or Editor: Alfred Jones x
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Abstract

A laboratory method based on adult feeding punctures was developed to rapidly evaluate cultivars and breeding lines of sweet potatoes Ipomoea batatas (L.) Lam for resistance to the sweetpotato weevil, Cylas formicarius elegantulus (Summers). Promising resistant lines can be identified, and the amount of field testing required to develop resistant lines is reduced. Preliminary data indicate that varying levels of resistance exist in sweetpotato.

Open Access

Abstract

Six sweet potato (Ipomoea batatas (L.) Lam.) lines with a wide range of objectionable fiber content were grown in one location in 1976 and in 2 locations in 1977 to study factors influencing the expression of that trait. We failed to identify environmental factors that would enhance expression of objectionable fiber but did find that large roots tended to have more objectionable fiber than did smaller roots. All roots of high fiber lines did not express objectionable amounts. About 10 US #1 but only 4 jumbo roots of each line would have to be evaluated to have a 95% probability of observing objectionable fiber in high fiber lines. However, Jumbo, US #1 and canning sizes all led to the same relative rankings of lines. Subjective evaluations of baked roots were as effective as objective laboratory tests and could be obtained concurrent with other necessary baking evaluations.

Open Access

The reactions of eight sweetpotato [Ipomoea batatas (L.) Lam.] introductions were categorized for root damage by wireworms, Diabrotica sp., Systena sp. (WDS), sweetpotato flea beetle (SPFB), and grubs. Clones were compared with resistant (`Regal') and susceptible (`SC-1149-19') entries. The number of resistant clones for the WDS, SPFB, and grubs were three, four, and one, respectively, intermediate five, four, and one, and susceptible zero, zero, and six, respectively. This test demonstrated that significant levels of soil insect resistance exist in these sweetpotato introductions for use by plant breeders.

Free access

Abstract

‘Excel’ sweet potato [Ipomoea batatas (L.) Lam.] was developed jointly by the USDA and the South Carolina Agricultural Experiment Station. This cultivar has high yield and excellent baking flavor, in combination with high levels of resistance to a wide array of disease and insect pests. Additionally, it has promise for use in snack foods.

Open Access

Abstract

Out of 38 lines of sweet potato [Ipomoea batatas (L.) Lam.] which had demonstrated some resistance in laboratory tests to the sweetpotato weevil, Cylas formicarius elegantulus (Summers), 13 lines had significant levels of resistance, based on weevil free yield in artificially infested fields in Yoakum, Texas. Two lines, W 125 and W 119, previously released as having weevil resistance, maintained a high level of resistance.

Open Access

Abstract

‘Sumor’, a multi-use sweet potato [Ipomoea batatas (L.) Lam.], was developed jointly by the Agricultural Research Service, U.S. Department of Agriculture, U.S. Vegetable Laboratory, and Clemson Univ., South Carolina Agricultural Experiment Station, Edisto Research and Education Center. This cultivar has potential as a high dry matter type for ethanol production and as a white-fleshed garden potato.

Open Access

This study was designed to determine if the preference of soil insects for sweetpotato [Ipomoea batatas (L.) Lam.] cultivars is affected by the proximity of resistant or susceptible plant cultivars at various spacings. Comparisons were made for damage caused by wireworms (Conoderus spp.), Diabrotica spp., Systena spp., sweetpotato flea beetles (Chaetocnema confinis Crotch), and grubs (Plectris aliena Chapin; Phyllophaga ephilida Say) in previously reported resistant and susceptible cultivars. Field plots were planted with a resistant cultivar, a susceptible cultivar, or the two cultivars intermixed. Large roots exhibited more insect damage than medium and small roots. When plant spacing was increased, roots were larger and insect damage more severe. Mixed plantings of resistant and susceptible cultivars significantly reduced insect damage in the susceptible plants. Planting regime did not influence insect damage for the resistant cultivars.

Free access

Abstract

Six sweet potato (Ipomoea batatas (L.) Lam.) breeding lines, W-71, W-115, W-119, W-125, W-149 and W-154, possessing moderate levels of resistance to the sweet potato weevil, Cylas formicarius elegantulus (Summers), in combination with resistances to other released. They have dark orange flesh, relatively high yields and generally acceptable canning and baking qualities.

Open Access

Abstract

Forty-five lines of sweet potato (Ipomoea batatas (L.) Lam) were rated for resistance to the sweet potato weevil in artificially infested fields at Savannah, Georgia and at Yoakum, Texas. Ten lines were resistant in Savannah, 16 lines in Yoakum, and 3 lines were resistant in both locations.

Open Access