基于dsPIC30F5015的苗盘自动输送机构控制系统

针对目前移栽机中苗盘输送机构定位精度低、冲击大、调整不便、智能化程度低等问题,设计了一种基于ds PIC30F5015和Lab VIEW的苗盘自动输送机构控制系统。采用伺服电机作为动力源,并用光电编码器采集伺服电机转速,设计了以高性能微控制器ds PIC30F5015为核心的硬件系统。采用模块化程序设计思想,在MAPLAB IDE开发环境下,开发了下位机软件;采用Lab VIEW平台开发了上位机控制软件。在苗盘自动输送试验台上进行了位置控制性能试验,结果表明:苗盘定位误差小于0. 32mm,相对误差小于0. 5%。该系统运行稳定,响应速度快,控制精度高,能够满足苗盘自动输送和精确定位的实际需求。     

河西农田养分投入产出平衡的长期定位研究

通过长期定位试验和作物养分含量分析,确定了河西地区小麦、玉米生产上测土配方施肥的可靠养分吸收参数,系统研究了河西灌区农田主要养分投入产出状况.连续24 a研究结果表明,长期连施化肥(NP,NPK)土壤氮素投入产出盈余率前期(1982-1990年)为8.6%～19.1%,最高时期(1997-2005年)的表观盈余率平均为29.0%～48.5%,扣除氮素损失后为负平衡;磷素化肥投产始终为正平衡,平均盈余率为57.4%～68.3%.钾素化肥投入不抵作物携带量,投产为负平衡.平均盈余率为-58.7%.说明连施化肥氮、钾养分投入不足.有机肥与化学肥料长期配合平衡施用(MNP,MNPK),氮素平均盈余率56.3%～61.5%,扣除氮素损失后为正平衡,盈余率平均为9.4%～10.9%;磷素投产为正平衡,平均盈余率高达249.9%～265.7%;钾素投产为负平衡,平均亏缺19.9%.有机肥连施钾素亏缺45.0%.增施化学钾肥,适量减少化学磷肥,保持氮素化肥投入水平,配施有机肥是科学的平衡施肥技术.     

平湖剑子麦、洪湖大太宝、崇阳红麦、延岗坊主、万年2号抗赤霉病性基因分析

本试验将抗性组分分析法与单体分析法相结合,进行了小麦抗性基因染色体定位和抗性评价。结果表明,平湖剑子麦是抗性较稳定的中抗至抗病品种,其抗性基因涉及6D、7A、3B、5B和6B 等染色体。洪湖大太宝抗性基因和感病基因并存,是一个中抗偏感或中感品种。崇阳红麦属感病品种。延岗坊主的抗性基因位于染色体3A 上,感病基因位于5D 上,是一个中抗品种.万年2号麦穗前期抗病基因位于4D 和5A 上,是中抗品种。两种方法结合研究多基因控制的赤霉病抗性,能获得比较准确的结果和较多的遗传信息。     

Investigations on resistance of oats to Heterodera avenae: Location of resistance genes

Summary By using 15 available mono/nullisomic lines of Sun II back ground, the Heterodera avenae resistance gene in Nelson (from Avena sativa CI 3444) and Panema (from A. sterilis I. 376) were located on monosome XV. Genes with smaller effects were located on monosomes VIII and X. The absence of these genes derived from Sun II would increase cyst production on plants lacking major resistance genes.     

关于牧草辐射育种几个问题的探讨

本文以牧草为材料 ,阐述了辐射敏感性的类型划分方法。将异花授粉牧草沙打旺辐照当代的种子直接播种在≥ 1 0℃ (年积温 2 3 0 8℃ )的低温下 ,提高了突变体的适应性 ,增加了选择的准确性 ,缩短了育种周期 ;M1代产生了显性早熟突变 ,M2 代有 2 7 2 %的植株保持早熟 ,比对照早开花 1 6～ 5 1d ,但仍有分离 ;5年育成彭阳早熟沙打旺 ,能在≥ 1 0℃ (年积温 1 847℃ )的地区开花结籽 ;播种当年始花序着生叶位与出苗至开花天数、株高和一级分枝呈极显著正相关。选育产草量高且早熟的沙打旺新品种 ,始花序叶位以在 9～ 1 0个为宜     

Chromosomal location of genes controlling grain size in a large grained selection of wheat (Triticum aestivum L.)

Summary Grain size in wheat is the most stable yield component and has a favorable effect on flour yield. To identify the chromosomes associated with the large grains of line G603-86, (grain weight over 60 mg and grain length of about 9 mm), F₃ lines, extracted from F₂ populations obtained from F₁ monosomics of crosses between G603-86 (P₁) and the monosomic set of Favorit (P₂) were tested in the field. ANOVA showed significant differences among parents for grain weight and grain length, but not for grain width or the factor expressing the difference in grain form and density. Homoeologous groups had significant effects on grain weight and on all components of grain weight, while genomes were not significantly different for any of these characters. Grain weight was significantly increased by chromosomes 6D and 4A of G603-86. Grain length was significantly increased by chromosomes 4A, 4B, 2B, 3A and 1B, grain width by chromosomes 1A and 1B, and the factor form-density by chromosomes 6D and 6A. The high grain size in G603-86 results from the effects of genes located on many chromosomes which affect grain dimensions, form and density.     

Chromosomal location of fertility restoring genes for ‘wild abortive’ cytoplasmic male sterility using primary trisomics in rice

Summary Identification and location of fertility restoring genes facilitates their deployment in a hybrid breeding program involving cytoplasmic male sterility (CMS) system. The study aimed to locate fertility restorer genes of CMSWA system on specific chromosomes of rice using primary trisomics of IR36 (restorer), CMS (IR58025A) and maintainer (IR58025B) lines. Primary trisomic series (Triplo 1 to 12) was crossed as maternal parent with the maintainer line IR58025B. The selected trisomic and disomic F₁ plants were testcrossed as male parents with the CMS line IR58025A. Plants in testcross families derived from disomic F₁ plants (Group I crosses) were all diploid; however, in the testcross families derived from trisomic F₁ plants (Group II crosses), some trisomic plants were observed. Diploid plants in all testcross families were analyzed for pollen fertility using 1% IKI stain. All testeross families from Group I crosses segregated in the ratio of 2 fertile: 1 partially fertile+partially sterile: 1 sterile plants indicating that fertility restoration was controlled by two independent dominant genes: one of the genes was stronger than the other. Testcross families from Group II crosses segregated in 2 fertile: 1 partially fertile+ partially sterile: 1 sterile plants in crosses involving Triplo 1, 4, 5, 6, 8, 9, 11 and 12, but families involving triplo 7 and triplo 10 showed significantly higher X² values, indicating that the two fertility restorer genes were located on chromosome 7 and 10. Stronger restorer gene (Rf-WA-1) was located on chromosome 7 and weaker restorer gene (Rf-WA-2) was located on chromosome 10. These findings should facilitate tagging of these genes with molecular markers with the ultimate aim to practice marker-aided selection for fertility restoration ability.     

Assessing eddy-covariance flux tower location bias across the Fluxnet-Canada Research Network based on remote sensing and footprint modelling

We describe an approach for evaluating the representativeness of eddy covariance flux measurements and assessing sensor location bias (SLB) based on footprint modelling and remote sensing. This approach was applied to the 12 main sites of the Fluxnet-Canada Research Network (FCRN)/Canadian Carbon Program (CCP) located along an east-west continental-scale transect, covering grassland, forest, and wetland biomes. For each site, monthly and annual footprint climatologies (i.e. monthly or annual cumulative footprints) were calculated using the Simple Analytical Footprint model on Eulerian coordinates (SAFE). The resulting footprint climatologies were then overlaid on to images of the Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) derived from LANDSAT Thematic Mapper (TM) imagery, which were used as surrogates of land surface fluxes to estimate SLB. Results indicate that (i) the sizes of annual footprint climatology increased exponentially with increasing cumulative footprint percentages and, for a given percentage of footprint climatology, the footprint areas were significantly different among the sites. Typically, the 90% annual footprint climatology areas varied from 1.1 km² to 5.0 km²; (ii) using either NDVI or EVI as the flux surrogate, the SLB was less than 5% for most sites with respect to the reference area of interest (A_r) at 90% annual footprint climatology (scenario A) and a circular area with radius of 1 km centred at the individual tower (scenario B), with several exceptions; (iii) the SLB decreased with increasing size of footprint climatology for all sites for both scenarios A and B; (iv) out of 12, eight flux towers represented most of the ecosystem surrounding the towers for an area of 0.3 km² up to 10 km² with a satisfactorily low bias of <5%, whereas four towers represented areas ranging from only 0.75 to 4 km²; and (v) the seasonal differences in monthly SLB using NDVI as a flux surrogate were about 1-4% for most sites for both scenarios A and B.     

Production of a Trisomic Series in Hordeum vulgare cv. 'Golden Promise' and its Use in Locating a Recessive Chlorina Gene

A trisomic series was produced from a triploid plant of barley (Hordeum vulgare L. cv. ‘Golden Promise’) derived from tissue culture. Its characteristics are briefly described and compared with two trisomic series reported previously. Trisomic number 1 performed poorly under glasshouse conditions. Number 2 failed to set any seed after selfing and must be maintained by pollinating with ‘Golden Promise’. The series was subsequently used to locate a recessive chlorina gene on barley chromosome 3.     

Location of genes for chlorophyll synthesis on specific arms of chromosomes in Triticum aestivum

Summary An Indian hexaploid wheat var. Pb C591 has been shown to carry gene(s) for chlorophyll synthesis on chromosome 3A (Singh & Joshi, 1979). In the present study cv. Pb.C591, its monosomic 3A and diteocentrics for 3A, 3BL and 3DL of var. Chinese Spring have been used. The F₂ segregation involving crosses between Pb.C591 as male, monosomic line 3A of Pb.C591 (female) and ditelocentrics 3A, 3BL and 3DL of cv. Chinese Spring as male and female respectively has been observed. It has been found that there are two dominant genes regulating chlorophyll synthesis in cv. Chinese Spring. These genes are located on chromosomes arms 3A and 3DS respectively.These chlorophyll synthetic genes must be the same which were postulated by Sears (1956, 1957) as the normal alleles of virescent gene v ₂ (which was located on 3BS) on chromosomes 3A(v ₁) and 3D(V ₃).