Chemical basis for resistance in sweetpotato Ipomoea batatas to the sweetpotato weevil Cylas puncticollis
Philip C. StevensonH. MuyinzaDavid R. HallElaine A. PorterDudley I. FarmanHerbert TalwanaRobert O. M. Mwanga
76
Citation
19
Reference
10
Related Paper
Citation Trend
Abstract:
Abstract The aim of this work was to determine the basis of resistance in a sub-Saharan sweetpotato variety, New Kawogo, to the African sweetpotato weevil Cylas puncticollis. This insect feeds on the roots, reducing quality and yield, and is the most important production constraint of sweetpotato in Africa. Laboratory bioassays were designed to determine how the performance of weevils differed on susceptible and resistant roots. Subsequently, liquid chromatography-mass spectrometry (LC-MS) analysis of the root surface and root latex identified quantitative and qualitative differences in the chemical profiles with higher levels of octadecyl and hexadecyl esters of hydroxycinnamic acids reported in the resistant variety. The compounds were synthesized to confirm their identity and incorporated into artificial diets for bioassays on C. puncticollis. High levels of mortality and developmental inhibition were recorded for larvae feeding on treated diets, and the effect was dose-dependent. Thus, in contrast to previous work on resistant African sweetpotato cultivars, resistance in New Kawogo is not only active, but is quantifiable and manageable for breeding. Work is underway to determine what effect these compounds have on the weevils at a molecular level. The inheritance of the root latex esters will be studied in new crosses and mapped in new populations using quantitative trait loci (QTLs) that are currently being developed.Keywords:
Ipomoea
Abstract The aim of this work was to determine the basis of resistance in a sub-Saharan sweetpotato variety, New Kawogo, to the African sweetpotato weevil Cylas puncticollis. This insect feeds on the roots, reducing quality and yield, and is the most important production constraint of sweetpotato in Africa. Laboratory bioassays were designed to determine how the performance of weevils differed on susceptible and resistant roots. Subsequently, liquid chromatography-mass spectrometry (LC-MS) analysis of the root surface and root latex identified quantitative and qualitative differences in the chemical profiles with higher levels of octadecyl and hexadecyl esters of hydroxycinnamic acids reported in the resistant variety. The compounds were synthesized to confirm their identity and incorporated into artificial diets for bioassays on C. puncticollis. High levels of mortality and developmental inhibition were recorded for larvae feeding on treated diets, and the effect was dose-dependent. Thus, in contrast to previous work on resistant African sweetpotato cultivars, resistance in New Kawogo is not only active, but is quantifiable and manageable for breeding. Work is underway to determine what effect these compounds have on the weevils at a molecular level. The inheritance of the root latex esters will be studied in new crosses and mapped in new populations using quantitative trait loci (QTLs) that are currently being developed.
Ipomoea
Cite
Citations (76)
Tissue-cultured, virus-tested (TC) plantlets of sweetpotato ( Ipomoea batatas var. batatas ) cultivars Okinawan, LA 08-21p, and Murasaki-29 were obtained from Louisiana State University Agricultural Center. The objectives of field trials conducted at the Kula Agricultural Park, Maui, HI, were to compare yield and pest resistance of 1) ‘Okinawan’ obtained from a commercial (C) field with TC ‘Okinawan’ and 2) TC Okinawan with the aforementioned TC cultivars. Trials were planted Oct. 2015 and Aug. 2016 and harvested 5 months later. Storage roots were graded according to State of Hawai’i standards, and marketable yields included Grades AA, A, and B. In addition, injuries due to sweetpotato weevil ( Cylas formicarius elegantulus ) or rough sweetpotato weevil ( Blosyrus asellus ) were estimated. In both trials, fresh and dry weights of marketable storage roots of TC ‘Okinawan’ were nearly twice those from commercial planting material. In both trials, marketable fresh weights differed among the three TC cultivars; however, significant interactions were found, indicating that yields of cultivars differed between years. In the first field trial, ‘LA 08-21p’ had fresh marketable yields 1.6 to 1.7 times greater than TC ‘Okinawan’ and Murasaki-29, respectively. In the second trial, fresh marketable yields of TC ‘Okinawan’ and ‘LA 08-21p’were similar and 1.7 to 1.5 times greater than that of ‘Murasaki-29’, respectively. In both trials, ‘LA 08-21p’ had greater sweetpotato weevil injury than did the other two cultivars. Interestingly, in the second year, TC ‘Okinawan’ had greater rough sweetpotato weevil injury than did the other cultivars. Our results indicate that tissue-cultured planting materials increased marketable yields of TC ‘Okinawan’ compared with C ‘Okinawan’ sweetpotato and that the other TC cultivars did not produce greater yields than TC Okinawan.
Ipomoea
Field trial
Cite
Citations (0)
Twenty sweet potato ( Ipomoea batatas L.) cultivars, including two orange‐fleshed and 18 white‐fleshed types, were evaluated in the field for resistance to African sweet potato weevil ( Cylas puncticollis Boh.). The cultivars showed significant differences in weevil resistance in separate evaluation of roots and shoots. Cultivars with the most resistant roots were ‘TIS 3053’ and ‘TIS 3030.’ Cultivars with the most resistant shoots were ‘TIS 2532,’ ‘TIS 3017,’ and TIS 3030. A highly significant correlation (r = 0.74) was noted between weevil damage ratings of roots and damage ratings of shoots. A highly significant negative correlation between weevil root damage scores and root dry matter percentage was obtained (r = −0.56), but fresh root yield or average weight were not correlated with weevil damage.
Ipomoea
Cite
Citations (27)
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.
Ipomoea
Convolvulaceae
High resistance
Cite
Citations (12)
Ipomoea
Convolvulaceae
Cite
Citations (26)
The preferences of the West Indian sweet potato weevil, Euscepes postfasciatus (Fairmaire), to tubers of sweet potato, Ipomoea batatas (L.), for food and for oviposition were evaluated, and correlated to sweet potato’s resistance to immatures. Adults (parent) were released in a plastic box containing tubers of sweet potato cultivars and maintained for 5 d, after which the adults on each tuber were counted. All adults were then removed and each tuber was maintained separately. New adults that emerged from the tubers were counted. Cultivars were grouped by cluster analyses using the number of parent adults on the tubers and the number of new adults emerging from the tubers, adjusted for the weight of each tuber. Cultivars were divided into five groups: average level of preference, preferred, preferred for oviposition but not for food, preferred for food but not for oviposition, and not preferred. New adults from the first two groups took less time to eclose than those from the other groups, and their body size was smaller. In a second experiment, one to five cultivars were selected from each group and inoculated each tuber with 10 weevil eggs on each cultivar. Although the proportion of eclosed adults was not significantly different between cultivars, the time to eclosion was shorter and body size was smaller on preferred cultivars. The selection of tubers by parent adults was not linearly related with larval development, and did not reduce the survival of the immatures.
Ipomoea
Convolvulaceae
Cite
Citations (8)
Hypera postica
Cite
Citations (2)
Sweetpotato [Ipomoea batatas (L.)] germplasm was evaluated and used to determine the contribution of cultural practices including mulching and irrigation on yield of sweetpotato and the reduction of sweetpotato weevil (SPW), Cylas formicarius elegantulus (Summers) infestation, the most economically devastating pest of sweetpotato in the United States Virgin Islands (USVI). The germplasm evaluation trials were conducted using cultivars obtained from the U.S.A., Puerto Rico (USDA-TARS), St Kitts, and the USVI. Results indicated a high per cent SPW infestation on storage roots of high-yielding cultivars, but local cultivars produced lower yields than introduced cultivars. Most cultivars from Puerto Rico were very well adapted for production in the USVI. Mulching generally increased the yield of cultivar Sunny, with the plastic mulch producing the highest yield of medium-sized roots while grass mulch reduced SPW infestation of storage roots. Irrigation significantly increased marketable yields of storage roots compared to the rainfed treatment. Additionally, irrigation maintained at 40 kPa produced the highest yield of medium-sized storage roots which was significantly higher than the 20 kPa and rain-fed treatments. These studies indicate that for improved sweetpotato production in the USVI, growers should consider the use of locally adapted cultivars, mulching, and an optimum irrigation level.
Germ plasm
Ipomoea
Cite
Citations (2)
Se realizaron dos ensayos de campo en Puerto Rico, uno en Isabela y otro en Mayagüez, para determinar la susceptibilidad de varias cultivares de Ipomoea batatas (L) (Lam.) al piche de la batata Cylas formicarius var. elegantulus (Summers). El rendimiento total de las cultivares no se afectó por el daño inicial causado por el insecto, pero la calidad de los tubérculos si se afectó en ambos ensayos. El grado de susceptibilidad para cada ensayo se determinó mediante el daño interno y el número de larvas en los tubérculos. En Isabela, las cultivares WRAS-3, WRAS-7, WRAS-31, WRAS-36, Mojave y Gem fueron altamente susceptibles al ataque del piche, mientras que las variedades Regal y Sumor y la línea WRAS-27 lo fueron moderamente. En Mayagüez, las cultivares WRAS-36, Mojave, Miguela y Gem fueron altamente susceptibles al ataque del insecto. Las cultivares WRAS-3, WRAS-7, Resisto, Sumor, WRAS-25, WRAS-27, WRAS- 31, WRAS-35 lo fueron moderadamente. La variedad Regal y las líneas WRAS-37 y WRAS-40 fueron las más resistentes al ataque de C. formicarius.
Ipomoea
Cite
Citations (0)
In Cuba it is necessary to continue working in the search for new sweet potato cultivars that are better adapted to climate variations, to obtain the proposed, hybridization method was used through manual crossings and subsequent selections, specially to drought, in different environment conditions (G x A, according its acronyms in Spanish). The INIVIT B-50 cultivar has excellent agronomic characteristics such as: a cycle of harvest between 110-120 days, low affectation by weevil ( Cylas formicarius F.) and a potential yield of 58 t ha -1 of tuberus roots
Ipomoea
Cite
Citations (3)