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1.
LYU Li-Min ZHANG Shuai LUO Jun-Yu WANG Chun-Yi WU Dong-Mei LI Chun-Hua CUI Jin-Jie 《棉花学报》2013,25(6):533-540
The occurrence and damage caused by whiteflies, cotton aphids, cotton thrips, mirid bugs, and cotton spider mites in the Bt cotton field, including 18 monitoring sites distributed in Hebei, Shandong, and Henan Provinces, were investigated from 2011 to 2012. In order of incidence of plants with pests, it showed that: whitefly (99.17%) > cotton aphids (98.33%) > cotton thrips (74.58%) > mirid bugs (43.10%) > cotton spider mites (20.95%). Compared with other pests, whiteflies had a highest incidence in the flower and boll stage of Bt cotton in Henan Province, and mirid bugs and cotton spider mites mainly occurred in the flower and boll stage in Hebei Province. Conversely, cotton aphids and cotton thrips showed the highest incidence at the bud stage in Hebei and Shandong Provinces, respectively. The results indicated that non-target pests showed significantly different occurrence and damage rates in various developmental stages of Bt cotton in different regions. 相似文献
2.
Motoyuki Ishimori Hideki Takanashi Masaru Fujimoto Hiromi Kajiya-Kanegae Junichi Yoneda Tsuyoshi Tokunaga Nobuhiro Tsutsumi Hiroyoshi Iwata 《Breeding Science》2021,71(4):444
According to Fisher’s principles, an experimental field is typically divided into multiple blocks for local control. Although homogeneity is supposed within a block, this assumption may not be practical for large blocks, such as those including hundreds of plots. In line evaluation trials, which are essential in plant breeding, field heterogeneity must be carefully treated, because it can cause bias in the estimation of genetic potential. To more accurately estimate genotypic values in a large field trial, we developed spatial kernel models incorporating genome-wide markers, which consider continuous heterogeneity within a block and over the field. In the simulation study, the spatial kernel models were robust under various conditions. Although heritability, spatial autocorrelation range, replication number, and missing plots directly affected the estimation accuracy of genotypic values, the spatial kernel models always showed superior performance over the classical block model. We also employed these spatial kernel models for quantitative trait locus mapping. Finally, using field experimental data of bioenergy sorghum lines, we validated the performance of the spatial kernel models. The results suggested that a spatial kernel model is effective for evaluating the genetic potential of lines in a heterogeneous field. 相似文献
3.
棉花抗红铃虫性对产量性状的影响研究 总被引：1，自引：0，他引：1
以不同抗性类型的陆地棉抗虫品种(系)和常规棉品种(系)作亲本配制杂交组合,将亲本和F1代杂交种共20个材料在网室、田间进行抗红铃虫鉴定和棉花抗红铃虫性对棉花产量的影响研究,试验表明,具有外源抗虫基因的抗虫棉皮棉产量高,稳产性好,尤其是抗虫杂交棉具有明显的杂种优势。相关分析结果,棉花种子虫害率与皮棉产量、子棉产量、单株成铃数和霜前花率呈极显著负相关;与衣分和僵瓣黄花率成极显著正相关;与单铃重相关性较低。结果表明,利用外源抗虫基因转导的棉花新材料作为杂交亲本,可以培育出丰产高抗棉花害虫的棉花新品种,尤其适合培育抗红铃虫的杂交棉品种。 相似文献
4.
A. Ratnadass B. Cissé S. Cissé T. Cissé M. A. Hamada J. Chantereau P. Letourmy 《Euphytica》2008,159(1-2):135-144
The reaction of four sorghum cultivars to panicle-feeding bugs was assessed in small (15 m2) and large (0.5–1.0 ha) plots for 2 years in three villages of the Kolokani region (Mali). The aim was to explain the somewhat
contradictory earlier observations of pest infestation and damage in small experimental plots (on-station and on-farm) as
well as in farmers’ field surveys. Irrespective of the plot size, the local guinea sorghum cultivar Bibalawili was consistently
the least infested and damaged, followed by bug-resistant compact-headed cv Malisor 84-7, whereas the improved caudatum cultivar
Gadiabani, which had been disseminated for nearly a decade in the region, and the improved hybrid ICSH 89002, were the most
heavily damaged. When located along the border of large plots of a susceptible cultivar, small plots of the four cultivars
overall were less infested and damaged than when located along the border of plots of resistant cultivars. However, they were
more infested and damaged when located in the centre of large plots of susceptible cultivars than when they were in the centre
of resistant cultivar plots. In large plots, bug populations and damage decreased from the border to the centre. These results
suggest that, in addition to the mere plot size, plant breeders should take the genotypic environment of their experimental
plots into account, namely the vicinity of large plots of pest-susceptible or -resistant cultivars, and the position of the
test plots (border or centre) relative to these large plots. 相似文献
5.
试验采用裂区设计，以肥料为主区，密度为副区，研究高产杂交籼稻新组合“特优649”的密度和氮肥、磷肥、钾肥施用量与产量的关系，结果表明：当密度为37.5万穴/hm2，或株行距为20cm×13.2cm，氮肥施用量为225kg纯氮/hm2，其N，P2O5，K2O的比例为1.0:0.5:0.8时，产量最高，平均达9.24t/hm2，最高达9.36t/hm2。据此提出产量指标为9.0 t/hm2以上的优化农艺措施组合为：每hm2密度37.5万穴，每穴插2粒谷秧，纯氮用量225kg，P2O5用量112.5 kg ，K2O用量180.0kg，其中基肥为猪牛粪22.5t+30kg过磷酸钙；试验还提出了相配套的水分运筹方法。 相似文献
6.
Todd C. Wehner 《Euphytica》1986,35(2):493-501
Summary Three rapid tests for measuring yield (small plots harvested once-over, and single plants harvested at the green and at the mature fruit stage) of pickling cucumber (Cucumis sativus L.) were evaluated for efficiency compared with the standard multiple-harvest trial with 2 or 3 replications and large plots. Fifteen genotypes were tested in 1981 and 18 in 1982 to determine the correlation among the 4 methods. In 1981, single plants were tested at 4 densities to evaluate the effect of using spaced or crowded plantings in selecting for yield. The spaced and crowded plantings were less efficient than the standard density, but none of the single-plant tests run in 1981 or 1982 were more efficient than the standard method in measuring yield. The most efficient method was 1, 2 or 3 replications of small-plots harvested once-over at green fruit stage, with 160% more gain from selection expected than for the replicated, multiple-harvest trial. 相似文献
7.
Summary Four selection experiments were sown: single-row plots with single row-spacing (20 cm), single-row plots with double row spacing (40 cm), three-row plots and six-row plots both with single row-spacing (20 cm). Selection entries were mimiced by 16 different varieties or advanced breeding lines, which were also sown in a yield trial. Each experiment was laid out as a 4-times replicated randomized block design. Row length was 2 m. Alley borders and border-rows of multiple-row plots were harvested separately to evaluate the effects of different harvesting procedures on the selection efficiency. Removal of alley borders was found to be disadvantageous, since the gain in precision was more than offset by the loss in sampled area. Wide spacing of single-row plots improved the selection efficiency in comparison with normal spaced single-row plots. In multiple-row plots the selection efficiency was not improved by harvesting only the central rows.For gross plot yield (= yield of net plot + yield of alley borders) the differences in selection efficiency between the various selection plot-types were explained on the basis of the genetic variance, the environmental variance and the coefficient of genetic correlation with farm yield as determined in the yield trial. 相似文献
8.
空间统计分析在作物育种品系选择中的效果 总被引：2，自引：0，他引：2
为了研究空间统计分析法在作物育种田间试验品系选择中的效果,采用剩余误差空间相关线性混合模型对一个具有56个品系的小麦育种随机区组设计田间试验产量资料进行了空间统计分析。运用地理统计学中的半变异函数法确定剩余误差空间协方差的函数。结果表明,试验的剩余误差存在着典型的空间相关性,利用剩余误差空间协方差结构的信息可降低品系效应估计的误差和提高品系效应差异F检验与t检验的效率。此外,空间分析法对品系效应估计受试验条件不均匀的影响小,可导致较经典方差分析法不同的品系排序和优系选择结果。 相似文献
9.
J. E. Bradshaw 《Euphytica》1989,42(1-2):135-140
Summary Two experiments were done to evaluate the use of single-row plots for assessing dry-matter yield of swedes. In the first experiment the correlation between the dry-matter yields of 20 cultivars in unguarded single-row plots and those in guarded double-row plots was poor (r=0.39). It was improved (r=0.58) by adjusting the single-row plot fresh-weight yields for inter-plot competition, through an analysis of covariance in which the covariate was the mean of the adjacent plot yields, and then estimating the pure stand dry-matter yields. However, the correlation was still lower than that between unguarded double-row plots and the guarded double-row plots (r=0.73), and this latter correlation was also improved (r=0.82) by adjusting the fresh-weight yields of the unguarded plots for inter-plot competition.The second experiment provided an explanation for the partial success of the covariance adjustment. The individual neighbour effects of six cultivars were determined. Doon Major and Ruta Øtofte decreased the yields of adjacent cultivars whereas Dryden and Melfort increased them. Angela and Magres had little effect. The correlation between the dry-matter yield neighbour effects of cultivars and their fresh-weight yields was high (r=–0.81), but not complete. So although competitive ability was associated with root fresh-weight yield, other factors must also be involved.It was concluded that a two-replicate trial with unguarded double-row plots is preferable to a four-replicate trial with unguarded single-row plots for dry-matter yield assessment of early generation families in a pedigree swede breeding programme. 相似文献
10.
基于层次分析法的耕地细碎化程度多指标综合评价研究 总被引：1，自引：1，他引：0
为了探索耕地细碎化程度多指标综合评价的指标体系与方法,采用归纳演绎法、数学模型法、实证分析法,构建了新的耕地细碎化程度评价指标体系。该指标体系包含的7个指标按重要性大小排序为：地块平均面积、地块长度一致度、农户平均地块数、耕地方田率、地块行向一致度、农户现实耕地经营规模与适度规模的差距、地块道路通达度。基于层次分析法,用上述指标体系对西魏村耕地细碎化程度实证分析表明,西魏村耕地细碎化程度处于“较严重”的级别。评价结果反映了西魏村耕地细碎化的现状。研究认为,耕地细碎化程度评价的指标体系应该涵盖地块的空间属性与社会属性指标,该研究构建的指标体系及采用的层次分析方法,可以对一定区域内的耕地细碎化程度进行科学的量化与评价。 相似文献
11.
The variation of soybean seed protein content has been investigated in performance trials of maturity group 000 to I genotypes at different locations in the eastern part of Austria between 1992 and 1994. In all experiments evaluated, significant portions of spatial variation were identified which affected seed protein content in the range of ?25 to +30 g/kg. Lattice and neighbour analysis were more efficient than the randomized complete block design in reducing error variance in most experiments. Neighbour analysis was superior to the lattice design when soil trends were changing over short distances or in both longitudinal and latitudinal directions. In most instances, neighbour analysis based on two or three neighbouring plots at each side of a test plot was more efficient than an analysis using only the nearest neighbours. Residuals derived from neighbour analysis were also used to visualize spatial heterogeneity, and clear trends of protein content were identified for particular experimental sites. The ranking of genetic entries was considerably biased by spatial variations, which would have reduced the efficiency of selection for high protein content if genotype performance was not adjusted for field variation. 相似文献
12.
Reliable agronomic and fibre quality data generated in Upland cotton (Gossypium hirsutum L.) cultivar performance trials are highly valuable. The most common strategy used to generate reliable performance trial data uses experimental design to minimize experimental error resulting from spatial variability. However, an alternative strategy uses a posteriori statistical procedures to account for spatial variability. In this study, the efficiency of the randomized complete block (RCB) design and nearest neighbour adjustment (NNA) were compared in a series of cotton performance trials conducted in the southeastern USA to identify the efficiency of each in minimizing experimental error for yield, yield components and fibre quality. In comparison to the RCB, relative efficiency of the NNA procedure varied amongst traits and trials. Results show that experimental analyses, depending on the trait and selection intensity employed, can affect cultivar or experimental line selections. Based on this study, we recommend researchers conducting cotton performance trials on variable soils consider using NNA or other spatial methods to improve trial precision. 相似文献
13.
Intersubspecific hybrids between Medicago sativa subsp. sativa and subsp. falcata show biomass yield heterosis in space planted plots. Relative biomass yield of alfalfa is known to differ in space planted versus sward plots, although the magnitude of the difference is variable. The objective of this study was to determine if and how much of the biomass yield heterosis observed in space planted alfalfa hybrids was retained in sward planted plots. Two falcata genotypes (WISFAL-6 and PI502453-1) and three elite sativa genotypes were crossed in a diallel mating design. Progeny were transplanted into space-planted plots and harvested three times per year or drilled into sward plots harvested four times per year. Hybrids of WISFAL-6 with the sativa genotypes produced as much first harvest biomass yield as intra-sativa hybrids in space-planted plots and more in sward plots. Yield in subsequent harvests was lower than intra-sativa hybrids in sward plots only. Hybrids of PI502453-1 with sativa were generally lower yielding than intra-sativa crosses. A moderate correlation was observed between biomass yield in space planted and sward plots. Heterosis expression in swards was lower than that in spaced planted nurseries for progeny of both falcata genotypes. The increased plant-to-plant competition in swards is the likely cause of the loss of heterosis. 相似文献
14.
Selection for lodging resistance in Canadian hard red spring wheat under natural conditions is difficult due to the sporadic and often random nature of lodging events. We conducted field trials in Edmonton AB Canada (2000–2002) to determine if either a high seeding rate, or artificially inducing lodging (by dragging a weighted apparatus across plots at the early milk stage), would be an effective screen for determining genetic lodging resistance in wheat breeding programmes. For the 25 genotypes tested, applying artificial lodging at the experimental mean early milk stage was a suitable method to screen and identify lodging tolerant and susceptible genotypes. Tolerance to artificially induced lodging was mainly found within semi‐dwarf genotypes, and susceptibility was mainly found within Canadian bread wheat genotypes. Severe lodging resulted in yield losses as high as 40%. Lodging tolerant genotypes identified in this study are now being crossed into elite western Canadian bread wheat in an effort to increase genetic lodging resistance within Canadian breeding lines. 相似文献
15.
64份玉米自交系抗粗缩病的遗传变异分析 总被引：11，自引：0，他引：11
在玉米粗缩病重发区,对64份玉米自交系进行了2年3种环境下的抗病性鉴定。以3种环境的平均病株率为指标,筛选出高抗自交系12份、抗病系17份、中抗系18份、感病系12份和高感系5份。采用70对SSR引物在64份自交系中检测出276个等位基因变异,平均多态性信息量0.57,结合系谱资料和育种实践可将供试系划为6个杂种优势亚群BSSS、PA、Lancaster、旅大红骨、四平头和PB。根据自交系对粗缩病的抗性反应,发现PB和四平头亚群的病株率较低（1.60%和4.95%）,为抗玉米粗缩病育种的重要种质类群。 相似文献
16.
《Soil Technology》1988,1(3):223-234
Spatial variability of a field soil was studied using a neutron probe to measure soil water status of the plant root zone, and isotopically labelled fertilizers to evaluate fertilizer nitrogen uptake. The work was carried out long three 96 m transects with 63 plots each, the first being bare soil, the second planted to rye grass and the third planted to alfalfa.Autocorrelation and crosscorrelation analysis were used to evaluate spatial dependence of the measurements. Field variability in soil water content measurements was found to be space dependent over a distance of 6 m and this implied that size of sampling domain for water content measurements could be 12 m for the experimental field. The spatial variability measured in atmospheric nitrogen fixation of alfalfa showed rather close resemblance to the spatial variability observed in water content measurements and was related to spatial variability of available soil nitrogen. The main assumption made when the 15N methodology is used is that the ratio of percentage N derived from fertilizer over percentage N derived from soil is the same for the non-fixing reference crop and the fixing crop. Based on measurements made on ryegrass which was used as a reference crop to assess the nitrogen fixation potential of alfalfa, it was found that under these particular field conditions this ratio was space dependent with a zone of influence of 6 m, suggesting that the maximum distance between rye grass plots and its counterpart alfalfa plots could only be 6 m.The results are discussed in the context of improvement of field experimental designs. 相似文献
17.
为提高大规模品种试验的精确度，根据田间上土壤肥力连续原理，建立随机区组设计的一阶，二阶差分近邻小区模型，利用修饰极大似然法估计参数，相对于常规的方差分析，在误差模型与局控制方面作了改进，从而进一步控制了区组内小区异的异质性。 相似文献
18.
A method developed in coffee tree breeding to assess family competitioneffects (partner effects) in comparative variety trials was applied to thecocoa tree (Theobroma cacao L.). The study was conducted in ahybrid comparative trial planted in French Guiana, involving twelve familiesof 50 trees in a totally randomized single-tree plot design, at a density of1,667 trees per hectare. The trial was thinned at 10 years, at a rate of twoout of four rows. Competition was studied with reference to juvenile andadult vegetative vigour, and to periodic and cumulative yields (number ofpods, potential weight, average weight of one pod, and the production:vigour ratio). At the end of the trial, after thirteen years of monitoring,competition effects were revealed which explained 8 to 10% of theresidual variance after removal of the hybrid and micro-environment effects.These effects, which were detected as early as 18 months, occurred earlierthan generally acknowledged. Under the trial conditions, the families couldbe classed as aggressive, stimulating or passive for their neighbours.Vegetative vigour (trunk cross-section) explained 34% of the competitioneffects (partner effects), which, with hindsight, vindicated the use of theproduction : vigour ratio as the main selection criterion in cocoa breeding.The partner effects noted on the production variables were never explainedby any production variable, hence non-aggressive high-yielding families canbe selected. 相似文献
19.
Approaches for field assessment of resistance to leaf pathogens in spring barley varieties 总被引：3，自引：0，他引：3
The resistance of spring barley varieties to powdery mildew, leaf rust, leaf scald and net blotch was characterized by using results from inoculated small‐plot nurseries and larger survey plots subject to natural infection. The experiments were conducted in different environments. Both trial types often yielded complementary results with respect to the ranking of varieties suggesting that a recommended variety characterization should include both naturally infected survey‐type trials and nursery trials in which the most relevant pathogen isolates and/or isolate mixtures or populations are used for inoculation. Average and median values of the diseased leaf area of a variety were highly correlated with each other and with the ‘genotype main effect’ determined by joint regression analysis, whereas maximum diseased leaf area was poorly correlated with them. Statistics based on absolute disease severity values were highly correlated with the corresponding statistics derived from relative values. It is suggested that one should use at least two parameters to characterize the disease resistance of a variety, a parameter indicating the overall resistance level and a parameter indicating the potential susceptibility and/or resistance instability of a variety. For practical purposes, the genotype median and maximum, respectively, may represent these, although statistically more appropriate parameters do exist. 相似文献
20.
Summary The inheritance of resistance in cabbage (Brassica oleracea var.capitata) to damage caused byThrips tabaci Lindeman was studied in progeny from four crosses between resistant and susceptible inbred lines. In two families sharing the same susceptible parent, the narrow-sense heritability was calculated to be high (>90%), using the Warner method of calculation (Warner, 1952). The other two families, also sharing a susceptible parent, had very low narrow-sense heritability (0–11%). In three of the four families, however, the validity of the Warner calculations were called into question due to significant epistatic interactions. In all four families, the F1 populations approached or exceeded the susceptibility of the susceptible parent, indicating that susceptibility is generally dominant. The importance of epistasis and dominance suggests that tests of hybrid combinations to determine combining ability for thrips resistance may be required, rather than selecting only on the basis of thrips damage to the inbred lines. The technique of planting wheat upwind from the cabbage test plot did generate adequate levels of thrips pressure, but the infestation was uneven in two of the four blocks, so that reasonable replication of tests is required. 相似文献