|Chortyk, O - USDA-ARS (RETIRED)|
|Johnson, A - CLEMSON UNIVERSITY|
|Harlow, C - N.C. STATE UNIVERSITY|
|Sisson, V - N.C. STATE UNIVERSITY|
Submitted to: Tobacco Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 20, 1998
Publication Date: N/A
Interpretive Summary: There is interest in the commercial development of natural sugar esters as biorational insecticides for control of soft-bodied insects such as whiteflies and aphids. In this study, we measured the production potential of sugar esters by eight wild relatives of tobacco, Nicotiana species, under field conditions. Plants were grown in 1995 at Florence, SC, Charleston, SC, and Tifton, GA. All species survived transplantation well. In general, sugar ester levels increased with subsequent harvests, but survival was poor after the second cutting for some species. The highest production of sugar esters per leaf area was from Nicotiana trigonophylla. The sugar ester fraction from N. trigonophylla is comparatively easy to fractionate, and it yielded 2.2 kg of pure sugar esters per hectare. Because sugar esters from N. trigonophylla are active against aphids and whiteflies and because of this plant's great production potential, it appears to be a good source of sugar esters for use as a biorational insecticide.
Technical Abstract: The production potential of sugar esters from eight Nicotiana species was measured under field conditions. Nicotiana amplexicaulis (PI 271989), N. glutinosa (PI 555507), N. gossei (PI 230953), N. hesperis (PI 271991), N. langsdorffii (PI 42337), N. noctiflora (PI 417918 and PI 475832), N. palmeri (PI 555543), and N. trigonophylla (PI 555573) were grown in 1995 at Florence, SC, Charleston, SC, and Tifton, GA. Nicotiana gossei, N. langsdorffii, N. noctiflora, and N. amplexicaulis produced the most green-weight biomass per hectare. Sugar ester levels increased with subsequent harvests, but survival was poor after the second cutting for some species, especially N. gossei and N. glutinosa. The highest production of sugar esters per leaf area was for N. trigonophylla (171 ug/cm2) and N. palmeri (104 ug/cm2). Nicotiana trigonophylla yielded 6.2 g of pure sugar esters per 50-plant sample, compared with 1.6 g per 50-plant sample for N. gossei. Also, the surface component profile of N. trigonophylla is less complex than that of several other Nicotiana species, and the sugar ester fraction is comparatively easy to fractionate. Sugar esters from N. trigonophylla are active against soft-bodied insects such as whiteflies and aphids, and it appears to be a good source of sugar esters for use as a biorational insecticide.