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111.
为给果袋在优质柰李果生产中的科学使用提供技术支持和参考依据,以10年生柰李树为试材。以不套袋为对照,分别采用单层白色纸袋、双层外黄内黑纸袋对柰李果实进行套袋处理。对不同处理下柰李果实基本品质、色泽、挥发性物质含量变化情况进行测定和分析。结果表明,不同处理间果实纵径、横径、侧径和单果重均未见显著差别。与不套袋相比,套袋能显著增加L*值、a*值、b*值;单层白色纸袋和双层外黄内黑纸袋处理可溶性固形物分别降低17.70%和8.04%,只有单层白色纸袋处理存在显著差异;果实中挥发性物质的总含量均提高,单层白色纸袋和双层外黄内黑纸袋处理分别提高52.60%和48.91%;套袋处理果实醛类香气物质含量显著提升。说明套袋处理可以明显提升果面光洁度,果皮色泽更鲜艳,果实挥发性物质总量提高,双层外黄内黑纸袋效果更好。  相似文献   
112.
While hybrid breeding is widely applied in outbreeding species, for many self‐pollinating crop plants, it has only recently been established. This may have had its reason in the limitations of methods available for hybrid performance prediction, in particular when established heterotic pools were absent. Genomic selection has been suggested as a promising approach to resolve these limitations. In our review, we briefly introduce the principles of genomic selection as an extension of marker‐assisted selection using genome‐wide high‐density molecular marker data and discuss the advantages and limitations of currently used algorithms. Including the outcome from a recent extended approach to hybrid wheat as a timely example, we summarize current progress in empirical studies on the application of genomic selection for prediction of hybrid performance. Here, we put emphasis on the factors affecting the accuracy of prediction, pointing in particular to the relevance of relatedness, genotype x environment interaction and experimental design. Finally, we discuss future research needs and potential applications.  相似文献   
113.
Grain yield and protein content are traits of major importance in wheat breeding, but their combination is challenging due to a tight negative correlation. Protein yield and grain protein deviation have been proposed as selection criteria to simultaneously improve both traits. Sedimentation volume is an indicator of protein quality, which plays an important role for bread‐making quality in wheat. All these traits have been investigated in our study with 135 parental inbred lines, their 1,604 hybrids and 10 commercial check varieties evaluated at five environments. The focus of our study was to investigate the usefulness of the grain protein deviation and to define a bivariate model for calculating the grain protein deviation. Further, we compared line and hybrid wheat for grain yield and quality‐related parameters such as protein content and sedimentation volume. The grain protein deviation determined with a bivariate model delivered robust estimates of variance components and enabled a balanced selection of genotypes with improved protein content and grain yield across different quality classes. Although heterosis for protein content and sedimentation volume was negative, hybrids had a higher grain protein deviation as well as higher grain yield at a given sedimentation volume or a given protein content than line varieties.  相似文献   
114.
为改善杏花银梨的品质,提升商品竞争力.以改造前后的梨园为研究对象,研究有机无机肥配施对杏花银梨果园土壤营养成分、土壤微生物和土壤酶活性以及果实基本品质、单糖组分、氨基酸组分以及香气成分的影响.结果表明:有机无机肥配施处理后果园土壤中速效磷提升了63.79%、速效钾元素含量提升了252.30%、细菌总量增加了203.43...  相似文献   
115.
Traditionally, high amylose starch (HAS) from maize (Zea mays L.) has been mainly used as an ingredient in gum candies and as an adhesive for corrugated cardboard. Two recent advances have increased interest in the use of HAS. The first one has been the development of starch-based biodegradable thermo plastics. Second, high amylose maize is a source of resistant starch (RS), a type of starch that resists digestion. As a food additive, consumers can benefit from added RS since it will lower the glycemic index and the risk of colon cancer in accordance with recent research in food science. Normal maize has about 25% amylose starch. A maize inbred line, GEMS-0067 (Reg. no GP-550, PI 643420) possesses high amylose modifier gene(s) that, together with the recessive amylose extender (ae) gene, raises the starch amylose percentage to at least 70%. The objective of this study was to determine the gene effects, non-allelic interactions and heritability of high amylose content in maize using Bogyo’s triploid model. Nine populations were derived from a cross between H99ae, a maize inbred line with 55% amylose starch, and GEMS-0067. Data were collected from two locations in Missouri (MO) and South Dakota (SD) over 2 years (2005 and 2006). Incomplete dominance explained some of the inheritance of HAS. Maternal effects were also detected. The triploid models for MO and SD were separately established based on the corresponding data in 2005 and 2006. The additive and type 1 dominance effects in MO, and the additive, type 1 dominance, type 2 dominance, and additive × additive in SD were significantly different from zero meaning that those effects played an important role in amylose synthesis. Both broad-sense and narrow-sense heritabilities were high indicating that high amylose content could be effectively selected for in a segregating population.  相似文献   
116.
茄子氮磷钾养分效应研究   总被引:2,自引:1,他引:2  
为了提高土壤养分供应量及强度、平衡茄子生产养分供求矛盾,探讨适宜茄子高产种植的氮磷钾最佳养分配方。以“农夫3号”为材料,采用“3414”设计方案,试验共设14个处理,3次重复,开展田间试验。结果表明:不施肥情况下茄子产量显著低于施肥处理,在不同施肥措施中N2P2K2处理的产量最高,不施或者少施氮、磷、钾中的任何一种养分均不同程度导致减产,其中氮肥的产量贡献率最大;氮、磷、钾养分供应不足均减少茄子有效结果数;茄子产量随着氮、磷、钾施用水平呈现一定趋势变化,氮素肥料是茄子产量形成最主要限制因子;增施氮、磷、钾养分肥料显著提高了植株养分含量及累积量,但降低了果实养分分配比例。通过茄子产量与养分用量模型分析,得到茄子推荐比例N:P2O5:K2O=1:0.55~0.83:0.63~0.84,施肥量为N:P2O5:K2O=392~433:240~243:271~330 kg/hm2。  相似文献   
117.
氯代芳香族化合物厌氧还原脱氯降解菌的研究进展   总被引:2,自引:0,他引:2  
氯代芳香族化合物可在厌氧条件下通过还原脱氯作用得以降解。本文综述了近年来还原脱氯降解菌分离、生理生化及酶学等方面的研究进展  相似文献   
118.
杉木、油桐、仙人草复合经营模式营养元素分配   总被引:7,自引:0,他引:7  
对福建建瓯1年生、2年生、5年生的杉木、油桐、仙人草复合经芝模式及对照杉木林营养元素组成进行了研究结果表明,1年生复合经营模式营养元素总吸收量是对照的8.13倍,仙人草采收移出生态系统营养元素为10.637kg/hm^2,占模式总吸收量48.99%,仙人草根和桐叶归还林地营养元素出为6.376kg/hm^2,占模式总吸收量的29.375。2年生复合经营模式营养元素移出量为21.42kg/hm^2,占2年生复合经营模式营养元素总量的22.935;归还林地;营元素总量为9.634kg/hm^2,占总量10.31%。5a后油桐采伐取走干(皮)营养元素大约占油桐营养元素总量的30%大部分营养元素归还林地。这对林地地力改善有利。  相似文献   
119.
[目的]研究西方蜜蜂群势变化与蜜源植物泌蜜的关系。[方法]结合当地每年主要蜜源植物和辅助蜜源植物的泌蜜特点从2012年1月~12月选出6群西方蜜蜂进行周年卵虫量、封盖子量、成蜂量和总的群势量的测定,并据此分别绘出不同的周年变化曲线图和总的蜂群群势变化曲线图。[结果]全年蜂群繁殖达3个高峰。5月15日蜂群群势达到全年第1个高峰,正是采集石榴蜜源的理想蜂群。7月15日达全年第2个高峰,10月15日达全年第3个高峰,正是为采集野藿香蜜源发展的强群。[结论]防治大蜂螨应在两个主要蜜源流蜜后期处于断子时用两种以上杀螨剂杀灭,防治小蜂螨应适时用升华硫配合杀螨剂施治。这为蜜蜂优质高产和产品质量安全提供了理论依据。  相似文献   
120.
Brown spot (BS) is a destructive foliar disease in tobacco (Nicotiana tabacum L.) and is caused by Alternaria alternata. BS poses a serious threat to tobacco production worldwide. To develop molecular markers that are tightly linked to BS resistance for marker-assisted selection (MAS), F2, F2:3 and BC3F2:3 populations were developed from a cross between a source of BS resistance Jingyehuang (JYH) and a BS susceptible flue-cured variety NC82. One hundred eighty-one F2 individuals, 180 F2:3 lines and 256 BC3F2:3 lines were evaluated for field resistance under different environments and quantitative trait loci (QTL) were identified by linkage mapping. A major QTL was mapped on chromosome15; this QTL explained 8.6–18.0% of the phenotypic variation under different conditions. Furthermore, 219 accessions were evaluated for their responses to BS at two sites, and association mapping (AM) was used to verify the chromosomal region harboring the major QTL. The AM results showed that six significant marker-trait associations were detected at two sites. Among these markers, the marker Indel53 within the specific chromosomal region exhibited the most significant association with resistance to BS and explained 20.0 and 21.5% of the phenotypic variation at the two sites, respectively. An approximately 2-Mb physical interval at the locus of marker Indel53 contained 31 predicted genes; quantitative real-time PCR results suggested that two of these genes (Nitab 4.5_0000264g0050.1 and Nitab 4.5_0000264g0130.1) were probable candidate genes for resistance to BS. In summary, our results suggested that the novel major QTL from tobacco variety JYH for resistance to BS provided partial effective resistance against A. alternata and was useful for MAS of resistance to BS in tobacco breeding.  相似文献   
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