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231.
我国燕麦种质资源的收集和评价   总被引:22,自引:0,他引:22  
我国是裸燕麦Avena sative 的起源地.20世纪50年代末我国开始了对燕麦种质资源的收集和整理工作.目前我国已经编入目录的燕麦种质资源共计2 978份其中裸燕麦1 699份,皮燕麦1 278份,野燕麦1份,还有1400佘份资源未编入目录.在已编入目录的燕麦种质资源中.已有1 142份被我国农作物种质保存中心长期库保存,504份被我国地方的一些研究单位中期库保存.对已收录的2 977份燕麦种质资源的评价情况进行了综述,包插对燕麦农艺学性状、抗性、籽实品质性状和遗传学性状的评价,这些信息可为今后我国燕麦种质资源的研究与燕麦育种工作提供帮助.  相似文献   
232.
Abstract

Rapid and uniform crop establishment is a prerequisite for efficient crop production and minimal environmental impact. Experiments were carried out in shallow plastic boxes placed directly on the ground in the field for studies of the effects of seedbed properties on emergence of various crops. This paper presents an analysis of the time required for germination and emergence under near-optimal seedbed conditions. The crops studied were barley, oats, wheat, pea, rape seed, white mustard, sugar beet, red clover and timothy. The time required for germination generally increased with size of the seeds, presumably because larger seeds needed more water to initiate germination. This applied both when comparing different crops and different seed sizes of the same crop. However, considerable differences occurred between seed lots of the same crop and there were greater differences between seed lots of the same crop than between the three small grain crops studied. Growth rate of the seedlings generally increased with seed size, presumably because of increased energy content in the seed. Consequently, the most rapid emergence was obtained from small seeds at shallow sowing and from large seeds at deep sowing. The crops studied had a minimum temperature for germination and seedling growth close to 0 °C. Under optimal seedbed conditions, thermal time required for 50% germination of barley was typically about 65 °C days over this base temperature and for seedling growth about 6 °C days cm?1. From 4 cm sowing depth, about 80 °C days were required for emergence but with considerable variations between seed lots. For rape seed or white mustard about 40 °C days were required for germination and about 8 °C days cm?1 for the seedling growth.  相似文献   
233.
本文通过对裸燕麦新品种“品二号”的生长发育和穗分化特点进行观察,提出了裸燕麦的水肥需求规律,为高产栽培提供了理论基础。裸燕麦在出苗至拔节前对水肥需求较少,拔节和抽穗期是水肥需求关键期,后期施肥应以磷、钾肥为主。  相似文献   
234.
Taing Aung  Hugh Thomas 《Euphytica》1978,27(3):731-739
Summary The gene for mildew resistance has been succesfully transferred into the cultivated oat from the wild oat species Avena barbata by means of an irradiation-induced translocation. The translocation has been shown to involve the long arm of chromosome ST21 of A. sativa, the short arm, the centromere and a segment of the long arm of the barbata chromosome.The transmission of the translocation is normal in the cultivar Manod in which it was originally isolated. When the translocation was transferred into other cultivars of oats, transmission through the male gametes was found to be impaired in some genotypic backgrounds. However, there was no evidence that the translocation had any deleterious effect on development and fertility in a range of cultivars.The translocation was shown to involve an exchange between nonhomoeologous chromosomes.The behaviour of the translocation in diverse genotypes indicated that the translocation was a new source of mildew resistance that could be easily used in a breeding programme.  相似文献   
235.
J. Šebesta  F. Kühn 《Euphytica》1990,50(1):51-55
Summary An accession of Avena fatua L. subsp. fatua v. glabrata Peterm. subv. pseudo-basifixa Thell. (A. fatua L. CS Sel. No. 1), collected in Czechoslovakia in 1971, was found to be resistant to a wide range of crown rust races. Analyses of crosses of this oat with cvs. Weikuss, Leanda, Mona, Rodney A, Rodney B, Rodney M, Dodge and K 316 indicated that the resistance of A. fatua CS Sel. No. 1 is conditioned by one recessive gene which is in interaction with one partially dominant gene with additive effect. The expression of rust reaction was affected by temperature. The crown rust resistance genes of A. fatua L. CS Sel. No. 1 were non-allelic with stem rust resistance genes Pg-2 (A) and Pg-4(B).  相似文献   
236.
Summary Yield formation of four Finnish and three Nordic oat varieties and 12 breeding lines developed at the Hankkija Plant Breeding Institute was studied during four different growing seasons (1986–1989). Seventeen characteristics were measured, including traits representing the date of maturity and architecture of the oat stand. The variation between genotypes in the examined traits was studied by means of two-way analysis of variance. The relationship between grain yield and morpho-physiological traits was studied by means of simple correlation analysis and stepwise regression analysis.The present study, carried out in highly dissimilar growing seasons, showed that ideotype breeding in the northern growing areas is likely to be successful only in moderate to optimal growing conditions. Based on the findings of this study, a productive oat ideotype for northern cultivation is composed of traits such as early maturation, high phytomass production with a high panicle weight resulting from a large number of grains. short straw length (high resistance to lodging), and reduced tillering. The importance of other factors influencing oat breeding in northern growing conditions is discussed.  相似文献   
237.
238.
    
A pathotype of Drechslera avenae (Eidam) Scharif exhibited host‐specificity, being pathogenic to Avena sterilis L but not to a number of related or unrelated species tested. In culture, the fungus produces a metabolite which was identified as the macrodiolide pyrenophorol (5,13‐dihydroxy‐8,16‐dimethyl‐1,9‐dioxa‐cyclohexadeca‐3,11‐diene‐2,10‐dione). This compound at a concentration of 320 µM was phytotoxic to A sterilis and considerably less so to Avena fatua L. The phytotoxicity was expressed as leaf necrosis on seedling cuttings partially immersed in pyrenophorol solution and as ‘green islands’ on detached leaves on which droplets of the solution were placed. Seed germination and seedling growth of A sterilis were not affected. Pyrenophorol at concentrations up to 640 µM did not cause any symptoms of phytotoxicity to a number of other monocotyledons or dicotyledons tested, with the exception of Lycopersicon esculentum Miller on which leaf necrosis was observed after application of the substance through the vascular system to seedling cuttings. These findings are discussed in relation to the exploitation of such compounds of natural origin as wild oat herbicides. © 2000 Society of Chemical Industry  相似文献   
239.
In order to comprehensively evaluate the productivity, stability and adaptability of varieties of naked oats, as well as the discriminative power and representativeness of testing sites in the alpine region of North China, data for six naked oat varieties and six testing sites in 2019 were analyzed and evaluated using the AMMI (additive main effects and multiplicative interaction) model and GGE (genotype main effect plus genotype-environment interaction) biplot. It was found that analyses of naked oats regional trial results using the two methods together reduced the statistical error and increased the ability to declare variety means significantly different, compared to traditional ANOVA methods. It was found that genotype, environment, and genotype×environment interaction effects all contributed to differences in grain yield. Variety 200910-28-4-3(G2) showed the best performance in both grain yield and stability of yield across sites, followed by varieties 200910-5-2(G3) and 200910-22-1(G4). In terms of the selection of regional adaptability test sites for varieties, Ulanqab pilot in Inner Mongolia had both good representativeness and strong discriminability, and was the most ideal test site. Chongli Shizigou Seed Farm and Zhangbei Base were also comparatively good test sites. This study provided a scientific evaluation of methodology for performance testing of naked oat varieties in the alpine region of north China and the results basis will assist future breeding and promotion. © 2022 Editorial Office of Acta Prataculturae Sinica. All rights reserved.  相似文献   
240.
Cover crop (CC) residues protect the soil from erosion and their permanence on the surface is largely influenced by their biochemical constituents. In this study, the dynamics of CC residue decomposition by applying mathematical models was described. The kinetics of decomposition of residues was obtained from a laboratory incubation experiment. Three CC shoot residues were applied on the soil surface and incubated for 362 days (with eight sampling times). Oats and vetch residues decomposed the most than clover, where k values were 3.6 × 10?3, 3.7 × 10?3 and 5.3 × 10?3 day?1, respectively. The three-compartment model (nonstructural carbohydrates, cellulose–hemicellulose and lignin) to simulate residue decomposition presented a close fit between simulated and measured data. The decomposition rate constant (k) of CC can be used to estimate how long residues will remain in the field and how they could affect soil organic carbon.  相似文献   
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