Genetic structure and diversity of natural populations of prickly lettuce (Lactuca serriola) were studied using AFLP markers and then compared with the diversity of the RGC2 disease resistance gene cluster. Screening of 696 accessions from 41 populations using 319 AFLP markers showed that eastern Turkish and Armenian populations were the most diverse populations and might be located in the orig...

To assess soil arsenic (As, in the form of arsenate) toxicity to plants, 6-d root elongation tests on wheat (Triticum aestivum L.) and lettuce (Lactuca sativa) were conducted in six Chinese soils freshly spiked with As. Plants were treated with 7 or 10 levels of As to establish concentration-effect curves. Median effective concentration and 10% effective concentration values were derived with r...

The reproduction and pathology of Pratylenchus penetrans has been observed on five cultivars of lettuce (Lactuca sativa var. scarola) : Parella, Lattughino biondo Lollo, S. Anna, Regina dei Ghiacci and Aurelia a t different soil temperatures and light exposure periods in climate-controlled units. The maximum population increase occurred a t 21-220 and a t 14 hourlday in Parella and S. Anna vari...

Light penetration through a Drummer silty clay loam and a Broomfield sand was measured spectrophotometrically and biologically. The spectrophotometric measurements showed that less than 1% of the incident light penetrated 2.2 millimeters at any wavelength between 350 and 780 nanometers for ped sizes up to 1 millimeter. Biological measurements with light-sensitive lettuce (Lactuca sativa) seeds ...

The reaction of the drug atenolol with hypochlorite under conditions that simulate wastewater disinfection was investigated. The pharmaceutical reacted in 1h yielding three products that were separated by chromatographic techniques and characterized by spectroscopic features. Two unusual products 2-(4-(3-(chloro(2-chloropropan-2-yl)amino)-2-hydroxypropoxy)phenyl) acetamide and 2-(4-(3-formamido...

Prolonged far red irradiation of imbibed lettuce seeds (Lactuca sativa L. cv. Grand Rapids) makes them unresponsive to subsequent treatment with gibberellin. It has been found that this effect is overcome by supplying gibberellin buffered at a low pH. On the basis of this and other evidence it is suggested that an extended far-red exposure causes a loss of gibberellin sensitivity through an eff...

Kaurenoic and grandiflorenic acid, isolated from Wedelia paludosa (Asteraceae), some derivatives from these acids (alcohols, esters, amides, lactones, oximes) and other naturally occurring kaurane diterpenes were tested for their action on the growth of radical and shoot of Lactuca sativa. Gibberellic acid, GA3, a commercially available phytohormone, belonging to the same class of diterpenes, w...

the specimens of the mealybug peliococcus kimmericus (kiritshenko) were collected on lactuca serriola l. from different parts of the fars province, iran. four parasitoid wasps, anagyrus orbitalis (ruschka), leptomastix histrio mayr, cheiloneurus kollari (mayr) and c. paralia (walker) (hym.: encyrtidae), were reared from this mealybug and the identifications confirmed by dr zhihong xu. the relat...

Gene escape from crops has gained much attention in the last two decades, as transgenes introgressing into wild populations could affect the latter's ecological characteristics. However, different genes have different likelihoods of introgression. The mixture of selective forces provided by natural conditions creates an adaptive mosaic of alleles from both parental species. We investigated segr...