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Soil-borne diseases and nitrogen availability are important limits on organic strawberry production. A trial using suppressive crop rotations to combat Verticillium wilt was conducted to see its effects on strawberry yields and net returns using a split-split-plot design. An ANOVA analysis was run to understand determinants of net returns. Results show that the suppression of wilt through the planting of non-host crops such as broccoli before the planting of strawberries can have significant effects on yield and net returns, and that suppressive crop rotations are potentially commercially viable.

Organic strawberry/vegetable producers in coastal California face soilborne disease, nutrient, and weed management challenges. In conventional systems, stringent regulations and air quality concerns make the sustainability of fumigantdependent systems uncertain. To evaluate efficacy of anaerobic soil disinfestation (ASD), mustard cake (MC) application and broccoli residue incorporation, we initiated trials at an organic farm (Org) and a conventional farm (Conv) with crop rotation (broccoli (Brassica oleracea L. italica) - strawberries (Fragaria ananassa), cauliflower (Brassica oleracea L. botrytis) - strawberries, or fallow - strawberries) as main plot in June 2011. Sub plots (ASD, MC, ASD+MC, untreated control (UTC), and fumigant (Pic-Clor 60. Conv only)) were applied prior to strawberry in October 2011. Cover crop and lettuce (Lactuca sativa) were grown after strawberries at Org only. Marketable fruit yield, weed density, and disease level were monitored during the strawberry season and soil inorganic N dynamics for the entire period. ASD+MC and ASD produced similar fruit yields as fumigant at the Conv site. ASD+MC produced greater fruit yield than UTC and MC at both sites and ASD at the Org site. ASD and ASD+MC produced high inorganic N in the soil 2 to 3 months after application at both sites. This caused salt damage on strawberry during early growth especially at Conv which may have reduced fruit yields in both treatments. Verticillium dahliae population in soil at strawberry transplanting was less than 1 microsclerotia/g soil at both sites. However, V. dahliae infection on strawberry plants at the end of the harvest season in Org was reduced by ASD and ASD+MC suggesting that the mechanisms of yield increase by ASD involved disease suppression. Weed suppression by ASD and MC was limited. The effect of broccoli rotation in V. dahliae and weed suppression was also limited and no synergistic effect of broccoli rotation with ASD and MC was observed.

According to the weak central coherence (CC) account individuals with autism spectrum disorders (ASD) exhibit enhanced local processing and weak part-whole integration. CC was investigated in the verbal domain. Adolescents, recruited using a 2 (ASD status) by 2 (language impairment status) design, completed an aural forced choice comprehension task involving syntactically ambiguous sentences. Half the picture targets depicted the least plausible interpretation, resulting in longer RTs across groups. These were assumed to reflect local processing. There was no ASD by plausibility interaction and consequently little evidence for weak CC in the verbal domain when conceptualised as enhanced local processing. Furthermore, there was little evidence that the processing of syntactically ambiguous sentences differed as a function of ASD or language-impairment status.

Non-word repetition (NWR) was investigated in adolescents with typical development, Specific Language Impairment (SLI) and Autism Plus language Impairment (ALI) (n = 17, 13, 16, and mean age 14;4, 15;4, 14;8 respectively). The study evaluated the hypothesis that poor NWR performance in both groups indicates an overlapping language phenotype (Kjelgaard & Tager-Flusberg, 2001). Performance was investigated both quantitatively, e.g. overall error rates, and qualitatively, e.g. effect of length on repetition, proportion of errors affecting phonological structure, and proportion of consonant substitutions involving manner changes. Findings were consistent with previous research (Whitehouse, Barry, & Bishop, 2008) demonstrating a greater effect of length in the SLI group than the ALI group, which may be due to greater short-term memory limitations. In addition, an automated count of phoneme errors identified poorer performance in the SLI group than the ALI group. These findings indicate differences in the language profiles of individuals with SLI and ALI, but do not rule out a partial overlap. Errors affecting phonological structure were relatively frequent, accounting for around 40% of phonemic errors, but less frequent than straight Consonant-for-Consonant or vowel-for-vowel substitutions. It is proposed that these two different types of errors may reflect separate contributory mechanisms. Around 50% of consonant substitutions in the clinical groups involved manner changes, suggesting poor auditory-perceptual encoding. From a clinical perspective algorithms which automatically count phoneme errors may enhance sensitivity of NWR as a diagnostic marker of language impairment. Learning outcomes: Readers will be able to (1) describe and evaluate the hypothesis that there is a phenotypic overlap between SLI and Autism Spectrum Disorders, (2) describe differences in the NWR performance of adolescents with SLI and ALI, and discuss whether these differences support or refute the phenotypic overlap hypothesis, and (3) understand how computational algorithms such as the Levenshtein Distance may be used to analyse NWR data. (Contains 2 tables and 1 figure.)

Background: Recent studies have indicated that many children with autism spectrum disorders present with language difficulties that are similar to those of children with specific language impairments, leading some to argue for similar structural deficits in these two disorders. Aims: Repetition of sentences involving long-distance dependencies was used to investigate complex syntax in these groups. Methods & Procedures: Adolescents with specific language impairments (mean age = 15;3, n = 14) and autism spectrum disorders plus language impairment (autism plus language impairment; mean age = 14;8, n = 16) were recruited alongside typically developing adolescents (mean age = 14;4, n = 17). They were required to repeat sentences containing relative clauses that varied in syntactic complexity. Outcomes & Results: The adolescents with specific language impairments presented with greater syntactic difficulties than the adolescents with autism plus language impairment, as manifested by higher error rates on the more complex object relative clauses, and a greater tendency to make syntactic changes during repetition. Conclusions & Implications: Adolescents with specific language impairments may have more severe syntactic difficulties than adolescents with autism plus language impairment, possibly due to their short-term memory limitations. (Contains 4 tables and 2 figures.)