Effect of allele combinations at Ppd-1 loci on durum wheat grain filling at contrasting latitudes

Flowering time is the most critical developmental stage in wheat, as it determines environmental conditions during grain filling. Thirty-five spring durum genotypes carrying all known allele variants at Ppd-1 loci were evaluated in fully irrigated field experiments for three years at latitudes of 41°N (Spain), 27°N (northern Mexico) and 19°N (southern Mexico). Relationships between weight of central grains of main spikes (W) and thermal time from flowering to maturity were described by a logistic equation. Differences in flowering time between the allele combination causing the earliest (GS100/Ppd-B1a) and the latest (Ppd-A1b/Ppd-B1a) flowering were 7, 20 and 18 days in Spain, northern Mexico and southern Mexico, respectively. Flowering delay drastically reduced the mean grain filling rate (R) and W at all sites. At autumn-sowing sites, an increase of 1°C in mean temperature during the first half of the grain filling period decreased W by 5.2 mg per grain. At these sites, W was strongly dependent on R. At the spring-sowing site (southern Mexico), W depended on both R and grain filling duration. Our results suggest that incorporating the allele combinations GS100/Ppd-B1a and GS105/Ppd-B1a (alleles conferring photoperiod insensitivity) in newly released varieties can reduce the negative effects of climate change on grain filling at the studied latitudes.     

温度对红曲菌以荞麦为基质固态发酵产色素的影响

发酵温度是影响微生物繁殖和代谢最重要的因素之一。利用红曲菌以荞麦为基质进行固态发酵,考查发酵温度对发酵产红曲荞麦中的生物量、色价和总黄酮含量的影响。结果表明,在发酵的前6 d,生物量随着发酵温度的升高而增大;6 d之后,30℃条件下生长量增长最快;发酵4 d后产生色素,黄、橙、红3种色素的色价在30℃条件下都增长最快。荞麦基质中的黄酮含量在发酵过程中变化不显著。     

立体绿化集成技术配套产品开发利用研究进展

当前立体绿化在国内多个大中城市中得到了蓬勃发展,促进了相关配套产品的研发和推广应用,同时新型的配套产品又推动了立体绿化的快速发展。本文对华南地区立体绿化基质产品、蓄水种植容器、植被毯、绿墙、生态植被砖等相关配套产品的研发及应用情况展开综述,旨在为今后能更有效地推广立体绿化集成技术及相关产品提供参考。     

High night-time temperature during flowering and pod filling affects flower opening,yield and seed fatty acid composition in canola

Winter canola (Brassica napus L.) is highly sensitive to increasing temperatures during the reproductive and pod-filling stages. Although the impact of high day-time temperature stress on yield and quality has been documented in canola, similar information under high night-time temperature (HNT) stress is not available. Using six hybrids and four open-pollinated cultivars, we observed a marked shift in peak flowering towards earlier, cooler hours of the morning under HNT. Averaged across two independent experiments, the photochemical efficiency of photosystem II was significantly decreased (3%), with a significant increase in thylakoid membrane damage (13%) in the leaves of susceptible cultivars under HNT stress. Similarly, the susceptible cultivars also recorded significant reduction in biomass (34%), pod number (22%), pod weight (37%) and total seed weight (40%) per plant while the same set of agronomic traits were not affected among the tolerant cultivars. Quantitative impact of heat stress was confirmed with increased sensitivity to HNT exposure from gametogenesis until maturity resulting in a significantly higher yield loss compared to stress exposure from post-flowering till maturity. HNT significantly decreased oil concentration, but increased protein concentration and saturated fatty acid levels in seeds of the susceptible cultivars. However, HNT had no impact on the unsaturated fatty acids in both hybrids and the open-pollinated cultivars. Breeding targets based on fatty acid composition for enhancing canola seed quality may not be easily amenable due to the inconsistency documented with the compositional changes under heat stress. In summary, our findings conclude that canola hybrids are better suited to regions experiencing heat stress, compared to open-pollinated cultivars, indicating the possibility of a complete shift to hybrid canola cultivation under predicted hotter climates in the future.     

不同裂解温度的污泥生物质炭理化特性分析

研究裂解温度对污泥生物质炭基础理化性质的影响,为安全、合理、高效处置污泥提供理论依据。将干燥污泥分别在200、300、500、700℃下进行热裂解处理(SBC200、SBC300、SBC500、SBC700),获得污泥生物质炭,测定其基础理化特性。结果表明：不同温度制备的污泥生物质炭表面颗粒结构完好,孔径范围均集中在10~50 μm,其中低温生物质炭SBC200表面较光滑,最可几孔径和中值孔径最大,分别为20.1 μm和14.8 μm,高温生物质炭SBC700表面较粗糙,比表面积最大,为5.98 m²/g。随裂解温度的提高,污泥生物质炭的产率、含水量、电导率、挥发分、阳离子交换量显著下降,全碳、氧、全氮、氢含量、有效磷和铵态氮均逐渐降低,pH和灰分含量显著增加。将污泥制备成生物质炭,是安全处置污泥的有效途径,低温制得的污泥生物质炭具有更大的提高土壤肥力的潜力,而高温制得的生物质炭在改良土壤酸性的应用上具有更大的潜力。     

内蒙古苏木山华北落叶松生物量及碳储量研究

森林生物量、碳储量是评价森林生长状况的重要指标。通过野外样地调查及室内烘干称重等方法,研究了苏木山林场不同林龄华北落叶松人工林乔木层、灌木层、草本层生物量以及乔木层净生产力、碳储量积累特点和变化趋势。结果表明:幼龄林、中龄林、近熟林平均木的生物量分别为26.41 kg、32.70 kg、107.81 kg;林分生物量分别为43.66 t·hm^-2、79.88 t·hm^-2、125.83 t·hm^-2;灌木层和草本层生物量之和分别为1.44 t·hm^-2、1.19 t·hm^-2、0.95 t·hm^-2;乔木层净第一生产力分别为2.56 t·hm^-2·a^-1、3.07 t·hm^-2·a^-1、3.40 t·hm^-2·a^-1,碳储量分别为22.20 t·hm^-2、40.55 t·hm^-2、63.80 t·hm^-2。苏木山华北落叶松人工林生物量、碳储量随林龄增加而增大,各器官碳储量从大到小依次为干>根>枝>皮>叶。     

火干扰对喀纳斯泰加林土壤有机碳的影响

为了研究不同火干扰烈度对喀纳斯泰加林土壤有机碳含量及碳储量的影响,以喀纳斯泰加林同一火烧时间不同火干扰烈度的火烧迹地为研究对象,对不同土层(0~10 cm,10~25 cm)有机碳含量进行测定并估算其碳储量,采用单因素方差分析及LSD多重比较进行差异显著性分析。结果表明,相同火干扰烈度下0~10 cm土层土壤有机碳及碳储量均大于10~25 cm土层。0~10 cm土层中碳储量表现为：未火烧>轻度火干扰>中度火干扰>重度火干扰,在10~25 cm土层中碳储量表现为：轻度火干扰>中度火干扰>未火烧>重度火干扰。0~10 cm土层的土壤有机碳含量和碳储量以及10~25 cm土层的有机碳含量损失程度会随着火干扰烈度的增加而增加。10~25 cm土层碳储量会在轻度和中度火干扰后出现增加。     

安康市核桃果实害虫种类调查研究

采用生长期定点定株定期果实害虫调查和贮藏期室内常温贮藏观测法,对安康市核桃果实害虫种类进行了调查。结果为安康市核桃果实生长期害虫有13种,隶属5目11科;核桃果实贮藏期害虫有3种,隶属2目3科;核桃生长期危害较大的果实害虫主要是核桃举肢蛾、核桃长足象、双鬃尖尾蝇和桃蛀螟;贮藏期危害较大的果实害虫是印度谷螟;首次发现并记录了角斑古毒蛾幼虫为害核桃幼果。     

海藻酸钠茶多酚复配涂膜对滇橄榄贮藏品质的影响

采用不同浓度的茶多酚和海藻酸钠对滇橄榄进行涂膜保鲜单因素试验,根据测定结果,选择浓度为0.10%、0.20%的海藻酸钠与浓度为0.75%、1.00%、1.50%的茶多酚进行复配涂膜,研究其对滇橄榄贮藏品质的影响。结果表明:经涂膜处理后的滇橄榄贮藏品质优于CK组,在6组不同浓度配比下,以0.10%海藻酸钠与1.50%茶多酚复配保鲜液的保鲜效果较好,可保持滇橄榄较好的感官品质,延缓果实失重率、可溶性固形物含量的升高和VC含量的下降,保持较高的好果率,抑制呼吸强度,能将滇橄榄保鲜期延长至15 d。     

Population dynamics of the potato cyst nematode,Globodera pallida,in relation to temperature,potato cultivar and nematicide application

The impact of increasing temperatures on the population dynamics of the soil-dwelling nematode Globodera pallida, a persistent and economically important pest of potatoes, was investigated. The reproductive factor (final population⁄initial population) and length of life cycle were found to be temperature sensitive. Pot experiments performed over 4 months allowed comparison of the effect on development of G. pallida of two temperature regimes: an average temperature comparable to current field conditions (14.3 °C) and an average temperature above current field conditions (17.3 °C). A larger second generation of juveniles was observed at 17.3 °C compared to 14.3 °C. Multiplication of G. pallida at field sites in Shropshire and East Lothian (average soil temperatures of 15.5 and 14.1 °C, respectively, during potato cropping) was also examined. A quantitative PCR assay and visual examination of roots were used to monitor the dynamics of the G. pallida populations in both field sites at 4-weekly intervals. Four cultivars, Desirée, Cara, Maris Piper and Estima, were grown with and without nematicide treatments. Nematicide treatments suppressed population increases at both sites. Females were observed on the roots of cvs Cara and Desirée at the end of the growing season in Shropshire, but not at East Lothian, and are likely to represent a second generation.