Work

Resistance to B emisia tabacibiotype B of S olanum pimpinellifoliumis associated with higher densities of type IV glandular trichomes and acylsugar accumulation

Year: 2014

Type: article

Abstract: Advances in tomato breeding for pest resistance have been achieved via gene introgression from wildSolanum(sectionLycopersicon) species (Solanaceae). Ninety‐nine F3families derived from an interspecific cross using as parental linesSolanum lycopersicumL. ‘LAM‐148' (susceptible standard) andSolanum pimpinellifoliumL. ‘TO‐937‐15’ (multiple pest resistance accession with typeIVglandular trichomes and acylsugar accumulation) were evaluated for their resistance against the whiteflyBemisia tabaci(Gennadius) (Hemiptera:Aleyrodidae) biotype B in free‐choice and no‐choice tests for oviposition and adult colonization. The parental lines and eight F3families with contrasting levels of resistance against the whitefly were selected and investigated in additional assays, which included the estimation of trichome densities and foliar acylsugar levels. The F3familiesBTR‐302 andBTR‐331 exhibited low amounts of eggs of whitefly and transgressive segregation for typeIVglandular trichome density with values greater than that ofTO‐937‐15 plants. However, the tested families did not surpass the total foliar acylsugar content found inTO‐937‐15.BTR‐331 exhibited low colonization in the free‐choice test and it was the least preferred F3family in the no‐choice test. The higher resistance levels ofBTR‐331 were associated with a positive combination of higher typeIVtrichome density and higher acylsugar levels. Some F3families displayed reduced fruit set due to the presence of flowers with style exertion of the antheridial‐cone. Fruit weight at harvest stage of the selected families (from 4.9 to 14.5 g) was lower than that ofLAM‐148 (139.5 g) but higher than that ofTO‐937‐15 plants (1.3 g). Therefore, although difficult to reach due to the simultaneous segregation of many polygenic traits, the combination of highB. tabaciresistance levels with superior horticultural traits is feasible. These results confirmTO‐937‐15 as a source of biotype B resistance. From the breeding standpoint, the genetic similarity betweenS. lycopersicumandS. pimpinellifoliumwould allow a more efficient resistance introgression by facilitating recombination and minimizing the potentially undesirable linkage drag associated with this trait.

Source: Entomologia Experimentalis et Applicata

DOI: 10.1111/eea.12189