钾肥和硅肥对油用亚麻茎秆抗倒伏特性的影响

为了优化油用亚麻抗倒伏的肥料运筹措施,以‘陇亚11号’和‘定亚23号’为试验材料,通过裂区设计,研究了钾肥（不施钾、52.5 kg K₂O/hm²和105 kg K₂O /hm² 3个水平）和硅肥（不施硅和90 kg SiO₂/hm² 2个水平）用量对油用亚麻茎秆形态学、力学抗倒伏特性及产量的影响。结果表明：‘陇亚11号’的株高、重心高度及茎粗、壁厚、抗折力均显著大于‘定亚23号’,茎秆形态学及力学抗倒伏特性的综合影响下,‘陇亚11号’较‘定亚23号’倒伏率提高21.24%而产量降低9.43%。钾肥显著改善了抗倒的茎秆表观形态学特性,施钾后茎粗、壁厚、茎秆抗折力、抗倒伏指数提高而株高和重心高度降低,千粒重和籽粒产量分别提高7.35%和9.34%。硅肥对茎秆形态学、力学特性及籽粒产量均无主效应,但硅肥与钾肥的互作使茎粗显著增加。抗倒伏指数与茎粗、壁厚呈显著正相关,与株高、重心高度呈显著负相关。品种间的茎秆抗倒伏特性差异较大,施用钾肥显著改善了抗倒的茎秆表观形态学特性,优化了茎秆机械性能,增强了油用亚麻的抗倒伏能力;供钾量较低时,硅肥与钾肥对茎粗的互作正效应明显。     

胡麻脂肪酸去饱和酶基因(fads)差异表达分析

为了了解fad基因在胡麻蒴果发育过程中对不饱和脂肪酸的调控,对高、中、低三个不同亚麻酸(C18:3)含量的胡麻品种(’CDC Gold’,‘内亚7号’,’Linola’)进行了不同时期的品质测定,以及脂肪酸去饱和酶2a基因(fad2a)、脂肪酸去饱和酶2b基因(fad2b)、脂肪酸去饱和酶2c基因(fad2c)、脂肪酸去饱和酶3a基因(fad3a)、脂肪酸去饱和酶3b基因(fad3b)的qRT-PCR定量分析。结果表明,随着蒴果成熟,可溶性糖含量呈降低趋势,粗脂肪与粗蛋白不断积累,且差异显著(p<0.05)。fad2a基因、fad3a基因以及fad3b基因在各个时期中的表达符合正态分布。以0 d的蒴果为对照,在胡麻种子形成过程中,‘内亚7号’的三个基因在5 d和15 d的表达量迅速增加,到30 d时急剧减少,15 d的fad2a基因表达量为5.23倍,fad3a基因表达量是fad2a基因表达量的14.52倍,fad3b基因的表达量是fad2a基因表达量的16.14倍,表明这三个基因参与不饱和脂肪酸积累过程。在低亚麻酸含量品种‘Linola’30 d中,fad3a基因是fad2a基因表达量的52.71倍,fad3b呈下调趋势;在高亚麻酸含量品种‘CDCGold’30d中,fad3a基因与fad2a基因的表达量均呈下调趋势,fad3b的表达量为3.92倍;在中等亚麻酸含量品种‘内亚7号’中,fad2a基因表达量降低了0.31倍,fad3a基因是fad3b基因表达量的1.87倍。fad2b基因、fad2c基因熔解曲线不稳定,峰值低,可以在后续试验中继续探索。     

抗白粉病胡麻种质资源田间鉴定与筛选

白粉病目前已成为影响胡麻产量和质量最常见的病害之一, 种植抗病品种是防控病害最经济环保的有效措施, 然而抗病亲本材料的缺乏已成为制约抗病品种选育的关键因素。为筛选出抗白粉病胡麻材料, 本研究在田间自然感病的条件下, 采用病情指数法对300份国内外胡麻种质资源材料进行了抗白粉病鉴定和评价。结果表明, 所有供试材料均程度不同地感染胡麻白粉病, 无免疫材料, 仅有5份材料为中抗; 其余295份均为感病材料, 其中8份材料中感, 52份材料感病, 235份材料高度感病。本研究可为抗白粉病胡麻品种的培育及相关抗病基因的发掘提供参考。     

赤霉素和磷肥配合施用对胡麻光合酶活性及其产量形成的影响

为探究赤霉素和磷肥配合施用对胡麻叶片光合酶活性以及籽粒产量的影响,以‘轮选2号’为材料,采用田间二因素裂区试验设计,研究了不同磷肥用量水平(P₀:0 kg·hm^-2 P₂O₅,P₁:67.5 kg·hm^-2 P₂O₅,P₂:135 kg·hm^-2 P₂O₅)和赤霉素(Gibberellin acid, GA₃)喷施浓度(G₀:0 mg L^-1,G₁:15 mg·L^-1,G₂:30 mg·L^-1)对胡麻光合同化酶活性、干物质积累量及籽粒产量的影响。结果表明：施磷和喷施赤霉素均显著提高了胡麻叶片RuBP(Ribulose-1,5-bisphosphate)、PEP(Phospho...     

Present status of genetics of rust resistance in flax

Summary Present knowledge of host genes conferring resistance to rust in flax and their genetics are reviewed. There are at least 34 genes conferring resistance to rust occurring in seven groups, namely, K, L, M, N, P, D and Q. Expression of these host genes is affected by temperature, genetic background and by the inhibitor gene present in certain rust strains. Recombination analysis indicates that genes within each of the M and N groups are probably closely linked and that of the L group are genetically complex. When testcross progeny between two genes of the L group were screened, susceptible and modified recombinants were recovered. Some of these susceptible recombinants yielded rare resistant revertants in their progeny. Mechanism of such reversion is not defined but appears to follow a definite pattern. It is also indicated that some of the recombinants represent new specificity. A molecular approach of cloning host genes in flax is described.     

Variation of cultivated flax (Linum usitatissimum L. subsp.usitatissimum) and its wild progenitor pale flax (subsp.angustifolium (Huds.) Thell.)

The domestication of cultivated flax (Linum usitatissimum L. subsp.usitatissimum) is briefly discussed. Using data documented as a matter of routine in genebank work, 63 accessions of cultivated flax from the flax germplasm collection of the Gatersleben Genebank are compared with 73 accessions of its wild progenitor pale flax (subsp.angustifolium (Huds.) Thell.), which have been observed in systematic field trials. Range of variation, genetically based variation, heritability and correlation of several characters are considered, especially with respect to the influence of domestication. Cultivated flax shows higher variation in the characters of generative plant parts, while pale flax varies more in the vegetative parts of the plant. The character correlations are similar in both subspecies. Of the 29 characters studied in pale flax the parameters describing tillering, height of plant, weight of seeds, width of petals and width of leaves are especially suitable for distinguishing between different accessions. In spite of the high heritabilities of most of the characters, the influence of the environment is significant in most cases.     

通径分析在油纤兼用亚麻产量分析中的应用

首先对18个胡麻(Linum usitatissimum Linn.)品系的5个产量构成性状及产量进行相关分析,指出单株粒数和分枝长与产量之间的相关性达显著水平,并且各性状之间还存在着相互作用、相互制约和相互促进的关系。因此对吉林省胡麻产量及其构成性状的关系须采用通径分析方法进行分析,以估算每一个性状对产量的直接作用,以及一个性状通过另一个性状对产量的间接作用。通径分析结果表明,在吉林省提高胡麻产量,可主要通过提高单株粒数和增加分枝数来实现;返青将致使胡麻减产。     

Response of grain yield and related agronomic traits of oilseed flax to diversified cropping rotations北大核心CSCD

This research aimed to identify a suitable planting pattern for oilseed flax production in a dry-farming region. A long-term field experiment was started in 2012 with a 4-year crop rotation cycle,designed to measure the effects on flax crop performance of previous crop,and various patterns of flax planting interval within the four-year rotation,compared with continuous flax cropping. Crop parameters measured included plant height,stem diameter,dry matter accumulation and distribution,and the experiment included six different crop rotation patterns：Flax→flax →flax→flax［（F）FFF］;Flax→wheat→potato→flax［（F）WPF］;Flax→potato→flax→wheat［（F）PFW］;Flax→ flax→wheat→potato［（F）FWP］;Flax→wheat→flax→potato［（F）WFP］and flax→wheat→potato→wheat［（F）WPW］. Results for the ninth year showed significantly increased grain yield（29. 89%-109. 57%）in crop rotation treatments compared with continuous cropping of oilseed flax. The ranking of the six tested rotations for yield was：（F）WPW>（F）FWP>（F）WFP>（F）PFW>（F）WPF>（F）FFF. The grain yield of oilseed flax was significantly affected by previous crop,frequency and years interval of flax cropping and number of years of continuous flax cropping. Yield was increased by 54. 45%-59. 29% under wheat stubble and potato stubble compared with oilseed flax stubble,and increased by 30. 66% and 109. 57%,respectively,under 50% and 25% frequencies,compared with 100% frequency. The grain yield of oilseed flax under two-year continuous cropping was higher by 29. 89% than four-year continuous cropping,and increased with increase in years interval between flax crops. Correlation analysis identified a significantly positive correlation between oilseed flax grain yield and effective capsule number,branch number and 1000-seed weight. The effective capsule number,branch number and 1000-seed weight of oilseed flax under rotation treatment were increased by 35. 88%-108. 91%,15. 47%-46. 19% and 14. 61%-16. 34%,respectively（P<0. 05）,compared with continuous cropping. In addition,the high grain yield of oilseed flax was accompanied by an increase in plant height,stem diameter and dry matter accumulation and these increases were,respectively,5. 11%-42. 24%,2. 77%-39. 92% and 31. 25%-117. 89% under the rotation regimes,compared with continuous cropping. Reduction in the number of years of continuous cropping years,change of crop stubble,decreased flax planting frequency and increased of interval between flax crops also improved flax crop performance. In summary,crop rotation improved the vigor of oilseed flax,resulting in greater plant height and stem diameter,improved dry matter accumulation and distribution,leading to increased branch number,effective capsule number and 1000-seed weight,and increase in the crop yield of oilseed flax. The results indicated that a multiple-crop rotation pattern was an effective way to avoid the yield reduction caused by continuous cropping in oilseed flax. The rotation： Flax→wheat→potato→wheat performed best among those tested and can be recommended as an appropriate cropping rotation for oilseed flax production in the dry region of northwest China. © 2022 Editorial Office of Acta Prataculturae Sinica. All rights reserved.     

Shoot cadmium concentration of soil‐grown plants as related to their root properties

Cadmium (Cd) is toxic to plants, animals, and humans. However, different plant species growing on the same soil may have very different shoot Cd concentrations depending on properties such as size of the root system, Cd net influx, shoot‐growth rate, Cd translocation from root to shoot, and the ability to affect Cd availability in the soil. To investigate possible reasons for different shoot Cd concentrations maize, sunflower, flax, and spinach were grown on an acid sandy soil (pH<$>_{{\rm{(CaCl}}_{\rm{2}} {\rm)}<$> 4.5, and C_org 2.8%) in a growth chamber with Cd additions as Cd(NO₃)₂ of none, 14, and 40 μmol (kg soil)^–1 resulting in Cd soil‐solution concentrations of 0.04, 0.68, and 2.5 μM. Only the high Cd addition caused a significant growth reduction of flax and spinach. The shoot Cd concentration was up to 30 times higher in spinach than in maize; the other species were intermediate. Of the plant properties studied only the variation of the Cd net influx explained the differences in shoot Cd concentrations. This was due to a decreased (maize, sunflower) or increased (flax) Cd concentration in soil solution or more effective uptake kinetics (spinach).     

除草剂残留对亚麻的影响及预防措施

长残效除草剂大面积施用及超量施用,对后茬作物亚麻造成严重危害,已成为影响我国北方亚麻主产区产业发展的重要因素。本文阐述了亚麻受药害原因及症状表现,列举了对后茬亚麻有影响的除草剂种类并提出了预防措施。