延长桃花源风景区桃花观赏期的品种组合方案

为解决桃花源风景区桃花群体观赏期较短的问题,2007~2008年在常德职业技术学院观赏桃花种质资源圃定点观察记载了34个观赏桃品种的开花物候期,拟定3月10日前进入最佳观赏期的为早花品种;3月11~20日进入最佳观赏期的为中花品种;3月20日后进入最佳观赏期的为晚花品种。从中筛选了24个品种,按照早、中、晚花品种株数数量以4∶3∶3的比例配置,形成延长桃花源风景区桃花观赏期的品种组合方案,可使桃花群体花期延长至52 d,从而提高了桃花源风景区景观价值。     

小麦抽穗后生理发育时间的计算与生育期的预测

采用每日热效应和基本灌浆期因子计算生长后期生理发育时间,并预测抽穗、开花和成熟等生育期。每日热效应是指受每日温度和品种温度敏感性影响的生育促进因子,其中温度效应用正弦函数来表达,而曲线的陡度用温度敏感性来调节。基本灌浆期因子是指小麦在最适条件下由灌浆至成熟所需的相对时间长短。通过调节品种的温度敏感性和基本灌浆期因子来统一不同小麦品种到达抽穗、开花和成熟的生理发育时间。结果表明,生理发育时间恒定的原     

Phenotypic plasticity of yield and phenology in wheat, sunflower and grapevine

This paper focuses on the interaction between genotype and environment, a critical aspect of plant breeding, from a physiological perspective. We present a theoretical framework largely based on Bradshaw's principles of phenotypic plasticity (Adv. Gen. 13: 115) updated to account for recent developments in physiology and genetics. Against this framework we discuss associations between plasticity of yield and plasticity of phenological development. Plasticity was quantified using linear models of phenotype vs environment for 169 wheat lines grown in 6 environments in Mexico, 32 sunflower hybrids grown in at least 15 environments in Argentina and 7 grapevine varieties grown in at least 14 environments in Australia.In wheat, yield ranged from 0.6 to 7.8 t ha⁻¹ and the range of plasticity was 0.74–1.27 for yield and 0.85–1.17 for time to anthesis. The duration of the post-anthesis period as a fraction of the season was the trait with the largest range of plasticity, i.e. 0.47–1.80. High yield plasticity was an undesirable trait as it was associated with low yield in low-yielding environments. Low yield plasticity and high yield in low-yielding environments were associated with three phenological traits: early anthesis, long duration and low plasticity of post-anthesis development.In sunflower, yield ranged from 0.5 to 4.9 t ha⁻¹ and the range of plasticity was 0.72–1.29 for yield and 0.72–1.22 for time to anthesis. High yield plasticity was a desirable trait as it was primarily associated with high yield in high-yielding environments. High yield plasticity and high yield in high-yielding environments were associated with two phenological traits: late anthesis and high plasticity of time to anthesis.In grapevine, yield ranged from 1.2 to 18.7 t ha⁻¹ and the range of plasticity was 0.79–1.29 for yield, 0.86–1.30 for time of budburst, 0.84–1.18 for flowering, and 0.78–1.16 for veraison. High plasticity of yield was a desirable trait as it was primarily associated with high yield in high-yielding environments. High yield plasticity was associated with two phenological traits: plasticity of budburst and plasticity of anthesis.We report for the first time positive associations between plasticities of yield and phenology in crop species. It is concluded that in addition to phenology per se (i.e. mean time to a phenostage), plasticity of phenological development merits consideration as a distinct trait influencing crop adaptation and yield.     

夜间断对苎麻开花的抑制效应

用白炽灯光间断夜间黑暗(夜间断),抑制了苎麻三麻开花,使其恢复营养生长,开花抑制的程度与苎麻所接受的夜间断光能相关,赤霉素可以减少雄花,使麻株增高,赤霉素结合夜间断处理,既可以完全抑制开花,又可使麻株增高,抑制苎麻开花使苎麻产量和质量都有明显改善,对第二年头麻产量也有良好影响。     

开花期和果枝部位对短季棉纤维品质及超分子结构的影响

 利用中棉所 16研究了开花期和果枝部位对棉纤维品质与棉纤维超分子结构各项参数动态变化的影响。研究表明 ,棉纤维长度、细度、成熟度及棉纤维强度等品质性状均随开花期推迟温度降低逐渐变差 ,相同开花期条件下果枝部位对棉纤维品质性状有一定影响 ,呈现出下部棉纤维品质略高于上部的趋势 ,但不显著。前期开花较早温度较高时下部果枝的超分子结构参数呈现出优于上部的趋势 ,与下部果枝的棉纤维品质略高于上部相一致 ,但果枝部位的影响并不能改变由于开花期推迟温度降低而对棉纤维超分子结构所产生的影响。     

玉米在不同水分条件下开花相关性状的QTL分析

Drought is one of the most important factors influencing maize yield.QTL analysis for related traits under water stress will facilitate the understanding of genetic mechanisms of drought tolerance and provide the basis of marker-assisted selection.The present study conducted QTL analysis of flowering-related traits including days to tasseling,days to silking,days to anthesis and anthesis to silking interval(ASI) under different water regimes in Xinjiang and Beijing,using 139 F_2∶3 families of A188×91 Huang 15.Totally 26 QTL were found to be associated with the flowering-related traits under normal water conditions,with the range of LOD of 2.62-8.40 and the range of phenotypic variance explained of 9.1%-43.2%.A QTL located near the marker"bnlg1176" on chromosome 8 controlled days to tasseling,days to silking and days to anthesis.Meanwhile,six QTL were found to be associated with the flowering-related traits under drought stress,with the range of LOD of 2.6-5.6 and the range of phenotypic variance explained of 9.5%-58.0%.A QTL also located near the marker "bnlg1176" on chromosome 8 controlled days to tasseling and days to silking,which could explain 16.6% and 20.5% of phenotypic variance.The genomic region near bnlg1176 on chromosome 8 is presumed to be an important region because eight QTL were found.     

Effects of Seeding Rate and Nitrogen Application Rate on Grain Yield and Protein Content of the Bread Wheat Cultivar ‘Minaminokaori’ in Southwestern Japan

Abstract

We examined the effects of seeding rate, 50 or 150 seeds m-², nitrogen (N) application rate at active tillering and jointing, 4 and 2 g N m-², respectively, or none, and N application rate at anthesis, 0, 2, 4, or 6 g N m-², on grain yield and protein content of a bread wheat cultivar, ‘Minaminokaori’, during the 2004–2005 crop season in southwestern Japan. Grain yield was similar at a seeding rate of 50 and 150 seeds m-². It was higher when 4 and 2 g N m-² were applied at active tillering and jointing, respectively (4–2N), than when no N was applied at these stages (0–0N). However, it was not influenced by N application rate at anthesis. Grain protein content was similar at 50 and 150 seeds m-². It was higher in 4–2N than in 0–0N. It was the highest when 6 g N m-² was applied at anthesis, followed by 4, 2, and 0 g N m-². The SPAD value at anthesis was higher at 50 than 150 seeds m-², but leaf area index (LAI) at anthesis was similar at 50 and 150 seeds m-² and protein content of grain was nearly the same at 50 and 150 seeds m-² irrespective of N application rate at anthesis. LAI and the SPAD value were higher in 4–2N than in 0–0N and the protein content of grain was also higher in 4–2N than in 0–0N irrespective of N application rate at anthesis. Therefore, both LAI and the SPAD value may be important traits related to the N application rate at anthesis suitable for yielding wheat grain with a high protein content.     

水稻开颖机理的探讨——Ⅲ.浆片的结构及其在开颖过程中内含物的变化

着生在小穗轴上的一对浆片是由许多大型薄壁细胞和分布均匀的若干条与小穗轴维管束相连的小维管束组成。每一浆片中小维管束数目因品种不同而异,一般含有15—20条。每一小维管束中具有1—5列导管,2—4列筛管和10个左右的小型薄壁细胞。小型薄壁细胞的细胞质浓,细胞器多,富含线粒体。不管是大型的还是小型的薄壁细胞之间的胞间     

干旱胁迫对玉米物候及产量组成的影响及模拟研究

为了研究产量关键期干旱胁迫对玉米物候及产量和产量组成的影响，评估作物生长模型对干旱胁迫下玉米物候和产量模拟的效果，基于锦州农业气象试验站2011-2015年分期播种试验玉米产量和产量组成观测资料，尤其是2014年和2015年天然干旱胁迫试验数据和2015年玉米开花、吐丝物候加密观测资料，分析了产量关键期干旱胁迫对玉米物候及产量和产量组成的影响，评估了CERES-Maize模型对不同降水年型玉米产量和产量组成的模拟效果，提出了模型改进的方向。结果表明，2014年和2015年辽宁省西部地区在玉米开花期前后经历了较严重的干旱胁迫过程，干旱胁迫导致玉米吐丝延迟程度大于开花，90%以上的植株能到达开花阶段，但仅有45%~88%的植株能到达吐丝阶段，直接影响株籽粒数（不同播期下的玉米株籽粒数相差32%）及最终产量（产量下降33%~78%）。CERES-Maize模型对正常年玉米产量及产量组成的模拟效果较好，对干旱年的模拟效果较差，部分原因在于模型在模拟玉米物候时不对开花和吐丝期加以区别，只考虑了温度对花期的影响，而没有考虑干旱胁迫下玉米因开花-吐丝间隔增大、雌穗发育异常、物候期推迟而造成的减产作用。因此，玉米产量关键期干旱胁迫直接影响玉米物候（开花-吐丝期），进而影响玉米穗粒数及最终产量；为提高干旱胁迫下作物模型的模拟评估能力，亟待开展干旱胁迫下基于冠层吐丝动态的玉米产量模拟研究。