Changes in amino acids in Cucumis melo in relation to life‐history traits and flight propensity of Bemisia tabaci

Abstract

Phloem amino acids in Cucumis melo L. were measured to determine whether changes in nitrogen availability might affect life-history traits and flight activity of Bemisia tabaci Gennadius (Homoptera: Aleyrodidae). During plant development, nineteen of the twenty common amino acids, plus hydroxyproline, citrulline, ornithine and γ -aminobutyric acid (GABA) were identified. For most essential amino acids, there were two peaks observed: an initial large peak associated with young plants, and a later small peak associated with senescing plants. For histidine, ornithine and citrulline, medium to large peaks in relative abundance were observed in mature plants. Arginine peaked during the first few weeks of development and was no longer detectable after wk 7. Serine and glutamine/glutamic acid were the only amino acids that peaked during plant senescence. Factor analysis was used to create a reduced number of orthogonal factors, which corresponded well with the trends that were observed for the various groups of amino acids. No single or combination of factors explained a significant amount of the variability in oviposition. For both males and females, factor 1 (predominantly essential amino acids) was the single most important predictor of adult weight. As the relative concentrations of essential amino acids decreased, whitefly weights decreased. Factors 1 and 3 (predominantly histidine and ornithine) were the most important predictors of developmental time. As these amino acids decreased in relative concentration, developmental time increased. Percent emergence was positively associated with factor 1 and negatively associated with factor 6 (predominantly aspartic acid). The distributions of flight duration for whiteflies emerging from young, mature and senescing melon plants were compared and they were always skewed towards short flights; however, the frequency of long-duration flights increased when melon plants began to senesce. Whiteflies from all plant-age categories were capable of flying for more than 2 h with fully developed eggs, but the presence of more than four mature eggs was associated with flights of reduced duration.

Effect of cotton nitrogen fertilization on Bemisia argentifolii populations and honeydew production

“…However, the phloem sap diet of whiteflies consists of virtually only one sugar, sucrose (Tarczynski et al, 1992). Many other features of a plant's physiology such as quality and quantity of amino acids (Blackmer & Byrne, 1999) and carbohydrate:amino acid ratio (Simpson et al, 1995) are known to be correlated with whitefly population development. Perhaps elevating plant nitrogen also raises plant glucose and it is the nitrogen rather than glucose per se which increases the insect population.…”

Shoot Feeding as a Nutrient Acquisition Strategy in Free-Living Psylloids

“…Data for 19 of the 20 common AAs and three other amine group containing metabolites (latter comprising 4-hydroxy-proline, ornithine and γ-aminobutyric acid (GABA); following [40]) are presented. The amino acids designated herein as essential are those identified by Douglas [41].…”

Reduction in the Fitness of <I>Bemisia tabaci</I> Fed on Three Previously Infested Tomato Genotypes Differing in the Jasmonic Acid Pathway

“…Plant nutritional content, particularly with respect to amino acid and carbohydrate levels, were able to affect the performance of phloem sap-feeding insects (Blackmer andByrne 1999, Kainulainen et al 2000). Phloem-feeding insects are intriguing because of their feeding mechanisms, which cause little damage to the plant tissue as they establish direct access to the amino acids and carbohydrates via the vascular tissue (Zarate et al 2007, Wu andBaldwin 2009).…”

“…The nitrogen present in phloem sap as free amino acids is regarded as a key nutritional factor for the growth, reproduction, and survival of phloem-sucking insects (Weibull 1987, Sandströ m and Pettersson 1994, Bi et al 2003. Positive correlations between amino acids and the population Þtness of whiteßies and aphids were established in cotton and pea plants (Blackmer andByrne 1999, Bi et al 2001). Furthermore, soluble sugars also affect the development, fecundity, and feeding preference of phloem-feeding insects (Simpson et al 1995, Joern and Behmer 1997, Messina et al 2002.…”