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Early-maturing rapeseed (Brassica napus L.) can alleviate the seasonal conflict between double-season rice (Oryza sativa L.) and rapeseed in the Yangtze River basin. In this study, the early-maturing rapeseed 'Shengguang 127' and intermediate-maturing cultivar 'Huayouza 9' (control) were sown on 2 October under five different planting densities (150,000 [D1], 300,000 [D2], 450,000 [D3], 600,000 [D4], and 750,000 plants ha-1 [D5]) during two growing seasons. The patterns of change in growth and development, yield, and yield components were investigated systematically to reveal the light energy and temperature production efficiencies and to quantify the ideal plant density for the early-maturing cultivar. The results showed that the early-maturing genotype advanced the whole growth period by 3 to 5 d under the same densities, compared with those of the intermediate-maturing genotype. The yield and population dry matter weight of both cultivars decreased after an initial increase, with the density increased initially from the D1 to D3 treatment, where it reached a maximum, and then decreased to the D5 treatment. Similar trends were observed in the light and temperature production efficiencies. Under the same densities, the production efficiencies of light energy and temperature in Shengguang 127 were 14.7 to 24.2% higher than those of the control, respectively; the yield and harvest indices in Shengguang 127 were significantly higher than those in Huayouza 9, which was attributed to the significantly higher 1000-seed weight. These results provide a theoretical basis for the agronomic management and breeding of high-yielding traits of early-maturing rapeseed in the Yangtze River basin. [ABSTRACT FROM AUTHOR]

9012AB, a recessive genic male sterility (RGMS) line derived from spontaneous mutation in Brassica napus, has been playing an important role in rapeseed hybrid production in China. The male sterility of 9012AB is controlled by two recessive genes (ms3 and ms4) interacting with one recessive epistatic suppressor gene (esp). The objective of this study was to develop PCR-based markers tightly linked to the esp gene and construct a high-resolution map surrounding the esp gene. From the survey of 512 AFLP primer combinations, 3 tightly linked AFLP markers were obtained and successfully converted to codominant or dominant SCAR markers. Furthermore, a codominant SSR marker (Ra2G08) associated with the esp gene was identified through genetic map integration. For fine mapping of the esp gene, these PCR-based markers were analyzed in a large BC1 population of 2545 plants. The esp gene was then genetically restricted to a region of 1.03 cM, 0.35 cM from SSR marker Ra2G08 and 0.68 cM from SCAR marker WSC6. The SCAR marker WSC5 co-segregated with the target gene. These results lay a solid foundation for map-based cloning of esp and will facilitate the selection of RGMS lines and their temporary maintainers. [ABSTRACT FROM AUTHOR]

Under direct-seeding method of sowing, seedling survival is adversely affected due to low temperature. The purpose of this study was to understand the morphological, physiological and molecular response of rapeseed resistance to low temperature stress at seedling establishment. Two varieties Qinyou No.7 (resistant biotype) and Fengyou 730 (sensitive biotype) were used for morphological and physiological experiments under low temperature stress and the resistant variety was used for transcriptome analysis based on the Illumina HiSeq 2000 platform. Results showed resistant variety initiated osmotic regulation system firstly and then triggered the antioxidant enzyme system when exposed to low temperature stress for long duration. The MDA content firstly tended to increase and then decreased in resistant variety, but it continued to increase in sensitive variety. Through transcriptome analysis of Qinyou No. 7 under low temperature for 0 h, 24 h, 48 h and 96 h, 2254 differentially expressed unigenes clustering in 7 expression patterns were participated in low temperature stress. Proteinserine/threonine kinases, myo-inositol-1-phosphate synthases and calmodulins, as the members of ABA and IP3/Ca2+ signal transduction pathway, played an important role in the low temperature stress. Different expressed genes dataset provides useful candidate genes for functional analysis of rapeseed resistance to low temperature. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the clinical efficacy and safety of intravitreal ranibizumab injections for the treatment of macular choroidal neovascularization (CNV) caused by pathological myopia. Between one and four intravitreal injections of ranibizumab were administered to 61 eyes from 61 patients who were diagnosed with macular CNV caused by pathological myopia. Following injection, the best-corrected visual acuity (BCVA), central macular thickness (CMT) and fundus fluorescein angiography (FFA) findings were evaluated monthly for a period of 6 months. Among the 61 eyes, 10 eyes received one injection, 44 received two injections, six received three injections and one received four injections (average, 1.97 injections). The BCVA was 0.02±0.01 prior to treatment and 0.30±0.03 subsequent to treatment, and this difference was statistically significant (P<0.01). The CMT was reduced by an average of 45.1 µm. Regarding the FFA results, 56 eyes had no CNV fluorescence leakage and five eyes had CNV fluorescence leakage following treatment; however, the intensity of CNV fluorescence leakage in the five eyes following treatment was lower than that prior to treatment. As a treatment for pathological myopia-induced macular CNV, intravitreal injections of ranibizumab may improve eyesight as well as the macular retinal tissue structure; thus, this is a safe and effective treatment method. [ABSTRACT FROM AUTHOR]