Polymorphism Association of Pituitary Positive Transcription Factor-1 Gene with Body Weight Traits in BC1 Hybrid Chicken (Gallus gallus gallus Linnaeus, 1758) from Cross Breeding between Female F1 Broiler and Male Pelung

Pituitary Positive Transcription Factor-1 gene is closely related to chicken growth and productivity. This research was conducted to detect Single Nucleotide Polymorphism in the exon 6 Pituitary Positive Transcription Factor-1 gene and its association with the bodyweight growth in the first backcross hybrid chicken. Procedures of the research included crossbreeding female first filial broiler chicken with male Pelung chicken to obtain first backcross hybrid chicken, Day Old chick hatched were maintained during 49 days, the bodyweight on the Day-Old chick measured every seven days, DNA was isolated by Chelex 5% method, Pituitary Positive Transcription Factor-1 gene was amplified by PCR, DNA band was visualized utilizing electrophoresis, and the PCR product was sequenced using Sanger method. The DNA sequence was aligned using Clustal omega software to gain Single Nucleotide Polymorphism. The Single Nucleotide Polymorphism was analyzed using the Pearson correlation test between chicken body weights of 49-days-old chickens with the polymorphism points. The conclusion indicated that the bodyweight of the first backcross hybrid chicken was higher than the Pelung chicken but lower than the first filial broiler chicken. Single Nucleotide Polymorphism was not found on the exon 6 Pituitary Positive Transcription Factor-1 gene in the first backcross hybrid chicken.

Fruit Quality of Pear Psylla-resistant Parental Germplasm

Sixteen interspecific backcross hybrid selections from various breeding programs have been selected as prospective parents for breeding for resistance of European-type pears to the pear psyllids (Cacopsylla spp.). The Pyrus communis × P. pyrifolia (n = 6) backcross selections are derived mostly from NJ 1, an open-pollinated P. pyrifolia seedling, and the Pyrus communis × P. ussuriensis (n = 9) backcross selections are derived from Illinois 76, an open-pollinated P. ussuriensis seedling, and one Pyrus communis × P. ussuriensis cultivar. Ratings of psylla resistance have been based primarily on multiyear orchard observations under no-pesticide and minimal pesticide conditions. To select the best prospective parents, data on fruit quality and tree traits were analyzed. Fruit characteristics included harvest date, fruit size and shape, skin color, percentage blush, russet, overall appearance, texture (flesh fineness), texture type, juiciness, overall grittiness and grit size, flavor acceptability and type, aroma, and a quality index, which was an unweighted total of the scores for appearance, texture, grit, flavor, and aroma. For this report, comparisons were made to ‘Bartlett’, the most widely grown U.S. pear cultivar. Both the P. communis × P. pyrifolia and Pyrus communis × P. ussuriensis backcross hybrid groups had significantly lower quality indices than ‘Bartlett’, and most individual traits were similar in this respect. There were significant differences among selections for all traits as were differences between years within genotype for most traits with some exceptions. Harvest date, percentage blush, appearance, juiciness, flavor, and the quality index were relatively stable from year to year. Flesh texture type varied within each group. The P. communis × P. pyrifolia selection NJ Rock R23 T252 had the highest quality index of the selections. For eight traits, various selections ranked higher than ‘Bartlett’, although the differences were not significantly higher with the exception of the russet score. Five selections appear to have sufficient quality and are being used as parents.

Inheritance of Resistance to Pear Psylla Nymphal Feeding in Pear (Pyrus communis L.) of European Origin

Pear psylla are serious pests of pear throughout North America and Europe. Inhibition of nymphal feeding has been identified as a key component of resistance, being correlated with inhibition of oviposition, mortality, and delayed development. Breeding for resistance would be aided by knowledge of the inheritance and relative breeding values of resistant parents. Nine seedling populations derived from crosses among five resistant European P. communis cultivars (‘Batjarka’, ‘Erabasma’, ‘Ilinjaca’, ‘Spina Carpi’, and ‘Zelinka’), a clone labeled ‘Obican Vodenac’, and two susceptible P. communis parents (‘Bartlett’ and ‘Sunrise’) were used in this study. The seedlings, ‘Bartlett’ as a susceptible control and NY10353 (a P. communis × P. ussuriensis backcross hybrid) as a moderately resistant control, were assayed for short-term survival and nymphal feeding after an infestation period of 2 days. There were no significant differences among the progenies and controls in mean proportion of live nymphs after 2 days. The distributions of live and feeding nymphs indicated some dominance for susceptibility in some crosses. There were few significant differences among crosses in the proportion of actively feeding nymphs; however, the two crosses involving ‘Erabasma’ exhibited significantly less feeding, indicating that ‘Erabasma’ transmitted resistance to nymphal feeding to its progeny to a greater degree than the other four resistant parents.

Hazelnut Accessions Provide New Sources of Resistance to Eastern Filbert Blight

A diverse collection of 58 hazelnut accessions, including Corylus avellana L. and interspecific hybrids, were evaluated for their response to the eastern filbert blight pathogen Anisogramma anomala (Peck) E. Müller after greenhouse inoculation. Evaluations were made using enzyme-linked immunosorbent assay and visual inspection. Forty-five of these became infected, 12 remained free of infection, and one gave inconclusive results. The 12 accessions showing complete resistance were European hazelnuts ‘Culpla’ from Spain and CCOR 187 from Finland; C. americana × C. avellana hybrids ‘G081S’, CCOR 506, and Weschcke selections TP1, TP2 and TP3; C. colurna × C. avellana hybrids Chinese Trazels Gellatly #6 and #11; Turkish Trazel Gellatly #3 and backcross hybrid ‘Lisa’; and C. heterophylla var. sutchuensis × C. avellana hybrid ‘Estrella #1’. In a second test, exposure of potted trees under structures topped with diseased wood confirmed the complete resistance of ‘Santiam’, four pollinizers, and ‘Ratoli’. However, a few small cankers were observed on ‘Closca Molla’ from Spain and OSU 729.012, with resistance from C. californica (A.DC.) Rose, in contrast to the results of earlier greenhouse inoculations.

Jumping performance and short-term repeatability of newly metamorphosed hybrid and parental leopard frogs ( Rana sphenocephala and Rana blairi )

Differential fitness between hybrid and parental genotypes plays a critical role in explaining the maintenance of natural hybrid zones as well as the production of novel genetic variation that may lead to diversification. Because locomotor performance is a reliable and practical measure of potential fitness related to morphological variation, we tested for differences in jumping performance among parental and hybrid genotypes of newly metamorphosed leopard frogs (Rana sphenocephala and Rana blairi). Tadpoles of the parental species and primary and backcross hybrid tadpoles, generated from artificial crosses (a total of five genotypes), were reared at two initial larval densities. Locomotor performance of newly metamorphosed frogs, as measured by jumping ability, was tested three times over 6 days in the laboratory at 24-25°C. Maximum and average jump lengths were greater for metamorphs reared at low larval density than for those reared at high density. Regression analyses indicated that 70-79% of the variation in jump length was due to body mass. When reared at low density, metamorphs of two F1 backcross genotypes (HB and HS) and one primary hybrid genotype (SB) jumped shorter distances than either parental species. When reared at high density, hybrid performance was indistinguishable from that of the parentals, except for one backcross hybrid (HB). Moderately high short-term repeatabilities (0.47-0.66) of metamorphs reared at the high density indicate that measures of performance in newly metamorphosed frogs can be predictive. We suggest that, owing to poor jumping performance, some hybrid frogs would be at a selective disadvantage relative to their parental species in the terrestrial environment and thus would partially reinforce mechanisms of reproductive isolation in this leopard frog system. Yet equivalent performance of some hybrids relative to the parentals, at least when reared at low density, suggests that hybrid lineages also have the potential to evolve independently in some environments.