European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae), displays a larval diapause in response to short photoperiods and is adapted to a variety of local conditions throughout North America. Hence, the effective photoperiod inducing larval diapause will differ among geographic ecotypes. This study considers the inheritance of photoperiodic larval diapause induction by hybridization and backcrossing two latitudinally distinct ecotypes of the European corn borer collected between 41° N, 96° W and 48° N, 96° W and under a range of photoperiods representative of their respective locations: from 14:10 to16:8 (L:D) h. The ecotype adapted to a bivoltine habitat (southeastern Nebraska) exhibited a shorter critical photoperiod (1480 h) than the ecotype (1533 h), originating from a univoltine habitat (northwestern Minnesota). Reciprocal F1 crosses exhibited intermediate values with indication of sex-linked inheritance. In addition, the male parent had significantly more influence on diapause incidence of subsequent progeny than the female. The F2 and backcross progeny further supported the supposition that diapause response is a sex-linked inheritance. The minimum number of genes estimates, and the response from backcross progeny, suggest that diapause response of European corn borer larva may be controlled by only a few loci. The overall results indicated that both ecotypes had adopted unique diapause responses, which ultimately lead to seasonal synchrony in their ecosystems.

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We developed highly reliable co-dominant SCAR markers linked to the Frl gene. FORL testing is difficult. The marker is expected to be quickly adapted for MAS by tomato breeders. Fusarium oxysporum f. sp. radicis-lycopersici causes Fusarium crown and root rot (FCR), an economically important soil-borne disease of tomato. The resistance against FCR is conferred by a single dominant gene (Frl) located on chromosome 9. The aim of this study was to develop molecular markers linked to the Frl gene for use in marker-assisted breeding (MAS) programs. The FCR-resistant 'Fla. 7781' and susceptible 'B560' lines were crossed, and F1 was both selfed and backcrossed to 'B560' to generate segregating F2 and BC1 populations. The two conserved set II (COSII) markers were found linked to the Frl gene, one co-segregated with FCR resistance in both F2 and BC1 populations and the other was 8.5 cM away. Both COSII markers were converted into co-dominant SCAR markers. SCARFrl marker produced a 950 and a 1000 bp fragments for resistant and susceptible alleles, respectively. The linkage of SCARFrl marker was confirmed in BC2F3 populations developed by backcrossing the resistant 'Fla. 7781' to five different susceptible lines. The SCARFrl marker has been in use in the tomato breeding programs in BATEM, Antalya, Turkey, since 2012 and has proved highly reliable. The SCARFrl marker is expected to aid in the development of FCR-resistant lines via marker-assisted selection (MAS).

The chickpea leafminer, Liriomyza cicerina (Rondani), is one of the most destructive insect pests of cultivated chickpea (Cicer arietinum L.) in the Mediterranean region under field conditions. For sustainable and environmentally friendly chickpea production, efforts have been devoted to managing the leafminer via decreasing the use of insecticides. Breeding of new resistant varieties is not only an efficient and practical approach, but also cost-effective and environmentally sensitive. To improve resistant varieties, breeders need reliable biochemical selection criteria that can be used in breeding programs. The first objective was to investigate the possible introgression of resistance to the leafminer from C. reticulatum Ladiz. (resistant) to C. arietinum (susceptible), then, to estimate inheritance of resistance to the leafminer for efficient breeding strategies, and finally, to study organic acid contents as selection criteria. Recombinant inbred lines (RILs) and their parents were evaluated using a visual scale of 1–9 (1 = free from leafminer damage and 9 = mines in more than 91% of the leaflets and defoliation greater than 31%) in the field under natural infestation conditions after the susceptible parent and check had scores of >7 on the visual scale. Superior RILs were found for resistance to the leafminer, and agro-morphological traits indicating that introgression of resistance to leaf miner from C. reticulatum to C. arietinum could be possible using interspecific crosses. The inheritance pattern of resistance to the leafminer in RILs was shown to be quantitative. Organic acids, including oxalic, malic, quinic, tartaric, citric and succinic acids in RILs grown in the field under insect epidemic conditions and in the greenhouse under non-infested conditions were detected by using high performance liquid chromatography (HPLC). In general, organic acids were found to be higher in resistant RILs than susceptible RILs. Path and correlation coefficients showed that succinic acid exhibited the highest direct effects on resistance to the leafminer. Multivariate analyses, including path, correlation and factor analyses suggested that a high level of succinic acid could be used as a potential biochemical selection criterion for resistance to leafminer in chickpea. Resistant RILs with a high seed yield resembling kabuli chickpea can be grown directly in the target environments under leaf miner infestation conditions.

During storage, chickpea (Cicer arietinum L.) is severely attacked by some bruchid species, especially Callosobruchus chinensis L. (Coleoptera: Bruchidae), resulting in losses in quantity and nutritional quality. In the present study, three species of Cicer including five accessions of Cicer arietinum L. (three kabuli and two desi chickpeas), four accessions of C. echinospermum P.H. Davis and five accessions of C. reticulatum Ladiz. were screened for resistance to C. chinensis in both free-choice and no-choice tests in the laboratory. Resistance was evaluated by measuring oviposition (number of eggs per seed), adult emergence (number of holes per seed), damaged seed rate and seed weight loss (%). The results revealed that no eggs were laid by the bruchid females to the C. echinospermum accessions in free-choice test, but in nochoice test only two C. echinospermum accessions (AWC 304 and AWC 305) had few eggs (4.3 and 3.3 eggs/seed, respectively). The highest rate of oviposition occurred in kabuli chickpeas, especially in YAR (25.1 eggs/seed in free-choice test). The accessions exhibited a similar pattern for adult emergence like in the oviposition rates. As for damaged seed rate, no damage was observed in both tests in the C. echinospermum accessions, except AWC 304 (6.7%) in no-choice test. The highest seed damage was seen in kabuli-type accessions, being 100% in YAR and ILC 8617. Considering seed weight loss, no weight loss occurred in the C. echinospermum accessions in both tests (except, AWC 304 in no-choice test) whereas the highest weight loss was seen in the kabuli-type accession, CA 2969 (28.6%) in free-choice test and in the desi type accession, ICC 4957 (35.0%) in no-choice test. Since lower numbers of eggs were laid on hairy, wrinkled/reticulated and dark seed accessions, these features seemed to be important in the preference of the bruchid for host selection and oviposition. These results suggest that resistant varieties can be used as gene sources in breeding new cultivars resistant to C. chinensis.

Sesame (Sesamum indicum L.) is an important oilseed crops widely grown in the southern regions of Turkey. Sesame seeds are primarily used in production of tahini as well as a garnish on sweets and bakery products in the country. Sesame plants with phyllody disease symptoms have increasingly been observed in the fields of Antalya province since 2007. The disease incidence in these fields was found to range from 37 to 62% (2). Infected plants display a variety of the disease symptoms such as virescence, asymptomatic shoot proliferation, infertile flower formation, reduced leaf size, and thin and weak capsule development. Total genomic DNA was extracted from samples collected from symptomatic (10 plants) and asymptomatic healthy-looking plants (10 plants) using a CTAB method and amplified with universal primers P1/P7 and R16F2n/R16R2 in direct and nested PCR, respectively (1,3). Amplifications of the DNA from the symptomatic plants yielded a product of 1.8 kb in direct and 1.2 kb in nested PCR assays. No amplification was observed in symptomless plants of the same age and collected from the same fields. Amplicons were purified, cloned in a pTZ57R/T Vector, and sequenced using a Beckman Coulter 8000 CEQ Genetic Analysis System. Four aligned 16S rDNA sequences (1,845 bp) were found to be all identical and belonging to one species. One sequence was deposited in GenBank under the accession number KC139791. A BLAST similarity search revealed that the sequence shared 99% homology with the sequences of the members of 16SrIX group phytoplasmas, ‘Brassica rapa’ phyllody phytoplasma (HM559246.1) and Iranian Almond witches'-broom phytoplasma (DQ195209.1) available in GenBank. In addition, iPhyClassifier software (4) was employed to create a virtual RFLP profile. The analysis showed that the RFLP profile of the sesame phytoplasma 16S rDNA sequence is identical (a similarity coefficient of 1.00) to the profile of the 16Sr group IX phytoplasma reference sequence (Y16389). A phylogenetic tree was also constructed using the neighbor joining plot option of the Clustal X program. The sequence clustered together with 16SrIX group phytoplasmas. To our knowledge, this is the first report of a natural infection of sesame by a new phytoplasma species from the 16SrIX group in Turkey. References: (1) D. E. Gundersen and I.-M. Lee. Phytopathol. Mediterr. 35:144, 1996. (2) C. Ikten et al. Phytopathogenic Mollicutes 1:101, 2011. (3) C. D. Smart et al. Appl. Environ. Microbiol. 62:2988, 1996. (4) Y. Zhao et al. Int. J. Syst. Evol. Microbiol. 59:2582, 2009.

Phyllody, a destructive and economically important disease worldwide caused by phytoplasma infections, is characterized by the abnormal development of floral structures into stunted leafy parts and contributes to serious losses in crop plants, including sesame (Sesamum indicum L.). Accurate identification, differentiation, and quantification of phyllody-causing phytoplasmas are essential for effective management of this plant disease and for selection of resistant sesame varieties. In this study, a diagnostic multiplex qPCR assay was developed using TaqMan® chemistry based on detection of the 16S ribosomal RNA gene of phytoplasmas and the 18S ribosomal gene of sesame. Phytoplasma and sesame specific primers and probes labeled with different fluorescent dyes were used for simultaneous amplification of 16SrII and 16SrIX phytoplasmas in a single tube. The multiplex real-time qPCR assay allowed accurate detection, differentiation, and quantification of 16SrII and 16SrIX groups in 109 sesame plant and 92 insect vector samples tested. The assay was found to have a detection sensitivity of 1.8 x 102 and 1.6 x 102 DNA copies for absolute quantification of 16SrII and 16SrIX group phytoplasmas, respectively. Relative quantification was effective and reliable for determination of phyllody phytoplasma DNA amounts normalized to sesame DNA in infected plant tissues. The development of this qPCR assay provides a method for the rapid measurement of infection loads to identify resistance levels of sesame genotypes against phyllody phytoplasma disease.