COMBINED USE OF ULTRASONOGRAPHY AND CONTRAST ENHANCED COMPUTED TOMOGRAPHY TO EVALUATE ACUTE NECROTIZING PANCREATITIS IN TWO DOGS

The imaging findings in two miniature schnauzers with acute necrotizing pancreatitis are described. Both dogs were treated previously for diabetes mellitus and hyperlipidemia. Vomiting, anorexia, and lethargy were observed in both dogs at presentation. Laboratory evaluations supportive of pancreatitis included left shift, abnormally high serum amylase and lipase activities, hypocalcemia, and abnormally high serum activities of liver enzymes. Sonographically, both dogs had diffusely enlarged hypoechoic pancreatic tissue with anechoic foci compatible with necrosis, abscessation, phlegmon, and pseudocysts formation. Contrast-enhanced computed tomography (CT) findings in both dogs were compatible with pancreatic necrosis. Dog 1 was managed medically for 11 days. Follow-up CT scan in this dog disclosed decreased pancreatic size and increased contrast enhancement compatible with partial resolution of pancreatitis.     

甘薯卷叶蛾幼虫空间分布型及应用研究

采用4种频次比较法和6种聚集指标公式测定了甘薯卷叶蛾幼虫空间分布型。结果表明，其在甘薯生长期间的分布是聚集分布。其聚集分布的原因是由环境条件所造成的。确定了理论抽样数据和田间抽样技术。     

Studies on the Developmental Genetics of Tiller Number in Three-line Indica Hybrid Rice

Following NC Ⅱ design, the developmental genetic behavior of tiller number (TN) in three-line indica hybrid rice was studied using additive-dominance developmental genetic models and the corresponding statistical methods. The results showed that dominance effects were predominant for TN. The expression of those additive effects were affected by environment and genotype interaction, but the expression of dominance effects were not affected. Heterosis was the strongest in the middle developmental periods of TN. Additive effects and dominance effects were selectively expressed throughout in the entire tillering developmental stage.Analysis of genetic correlation between TN at different stages and the productive panicles indicated that a close correlation appeared earlier in the populations with higher heterosis than in those with less heterosis. Utilization of heterosis at the middle tillering stage might enhance the final biomass but reduce the percentage of productive panicles.     

Interspecific hybridization of a multiploid mutant of durum wheat with rye and Triticum monococcum L. results in pentaploid hybrids

The multiploid mutant of durum wheat is a genotype that produces unreduced gametes. Our objective was to test the recovery of pentaploid hybrids in crosses of the mutant with rye and Triticum monococcum L. Compared with check crosses, the mutant had a two‐third reduction in percent seed set for rye crosses, but had only a slight decrease in crossability with T. monococcum. Pentaploid hybrids were associated with plump seeds of the mutant/rye cross, and with shrivelled seeds of the mutant/T. monococcum cross. We suggest that the endosperm balance number hypothesis explains the association of pentaploid hybrids with endosperm type. This association made for easy recovery of pentaploid hybrids from crosses to both species. Mature, plump seeds from the mutant/rye cross were germinated and pentaploid hybrids were recovered. One pentaploid hybrid was recovered for every 50.5 and 15.1 florets pollinated with rye and T. monococcum, respectively. Unreduced gametes in the multiploid mutant will facilitate interspecific hybridization by reducing the time to produce pentaploid plants.     

A procedure for combining a quantitative inheritance study with the first cycle of a breeding program

Summary The number of effective factors controlling the inheritance of a quantitative character can be estimated by analysis of F₃ lines where the parental lines are homozygous. The procedure is illustrated with data from a study of pod length inheritance in common bean (Phaseolus vulgaris L.). The mean pod length of Sprite, the parent with longer pods, was compared statistically with the means of F₃ progenies derived from F₂ plants obtained from the appropriate tail of the F₂ frequency distribution for pod length. The data indicate that analysis of F₃ progenies avoids much of the underestimation of the effective factor number which is characteristic of other procedures. The number of effective factors was estimated to be a minimum of 4 and the correlation between random F₂ parents and F₃ progeny means was r=0.82.Florida Agricultural Experiment Station Journal Series No. 406.     

Developmental abnormalities in the ovule and embryo sac of ulluco (Ullucus tuberosus) and their effect on seed set

Summary Ulluco (Ullucus tuberosus) is a vegetatively propagated crop plant that flowers abundantly but sets only few seeds. We examined if the low seed/ovule ratio can be explained by morphological abnormalities in ovules, embryo sacs or embryos. In 35 clones growing in the actual area of cultivation in Ecuador and in 5 clones grown in Finland flowers were analysed by clearing technique. About half of all analysed clones contained ovules and embryo sacs whose development was arrested, in two clones there were embryo sacs whose cell patterns were abnormal and in four clones there were double embryo sacs. There were both normal and abnormal ovules and embryo sacs in the same plant. Genetic load is suggested to be one of the causes for the low sexual fertility found in ulluco. It may be incapable of maintaining homeostasis of development of the ovule and embryo sac in a varying environment. The occurrence of developmental abnormalities should be studied in each clone intended for inclusion in traditional breeding programmes.     

小麦主茎总叶数的变异

小麦主茎总叶数是重要的植株性状。它也具有变异性。春型品种的主茎叶数少,冬型品种的主茎叶数多,过渡型品种居中。在不同播期中,强春性小麦的主茎叶数相近,一般春性品种变化不大。随着播期的推迟,过渡型和冬型品种的主茎总叶数逐渐发生变化,冬型品种的变化幅度大。冬播期中,在翌春出苗的情况下,所有品种的主茎总叶数都较少,     

Meiotic studies of spontaneous hybrids of Amaranthus: genome analysis

The meiotic behaviour of 13 spontaneous interspecific F₁ hybrids of Amaranthus was studied. The hybrids between species with n= 16 chromosomes had 16 bivalents but varied considerably in pollen stainability (0–55%). These results suggest the existence of cryptic structural hybridity. The hybrids involving A. cruentus (n = 17) and species with n = 16 (A. caudatus and A. quitensis) always formed 15II+1 III with very low pollen stainability (5–7%). Further observations indicated that Amaranthus species are allotetraploids with basic numbers of x= 8 and x= 9 but exhibit x= 16 and x= 17 as secondary basic numbers, as demonstrated by (a) the frequent presence of 811 + 171 in the meiosis of the hybrid A. spinosus (n = 17) × A. hybridus (n= 16); and the occurrence of secondary associations between bivalents in MI. Genomic formulae are proposed for each species, on the basis of the meiotic behaviour of the hybrids studied.     

A reciprocal F1 monosomic analysis of the genetic control of time of ear emergence,number of leaves and number of spikelets in wheat (Triticum aestivum L.)

Summary A reciprocal F₁ monosomic analysis of chromosomal differences between Spica and Bersée was carried out under controlled environment conditions. Chromosomes associated with differences in days to ear emergence, number of leaves and number of spikelets were identified. The results indicated that chromosome 2B of Spica carries a photoperiod insensitivity allele at the Ppd ₂ locus. Both Spica and Bersée appear to have a vernalization insensitity allele at the Vrn ₂ locus on chromosome 5B. On chromosome 3A, 4B, 4D and 6B factors were found with major effects on earliness per se, diffeences in ear emergence and number of spikelets which were independent of photoperiod and vernalization. The possibility that these factors influence growth rate is discussed.     

甘蓝型油菜株高、第一分枝高和分枝数的QTL检测及候选基因筛选

株高、分枝数及第1分枝高是油菜重要的农艺性状。本研究利用甘蓝型油菜GH06和P174杂交,F2通过单粒法连续自交至F11构建重组自交系群体,利用油菜60K芯片对该群体进行基因分型,构建高密度遗传连锁图谱。结果表明,该图谱包含2795个SNP多态性标记位点,总长1832.9 c M,相邻标记间平均距离为0.66 c M。在此图谱基础上采用复合区间作图法(CIM),检测到3个农艺性状的24个QTL。其中11个株高QTL分别位于A01、A06、A07、A08、A10和C06染色体,单个QTL解释5.00%~15.26%的表型变异;7个第1分枝高QTL分别位于A06、C05和C06染色体,单个QTL解释5.04%~12.99%的表型变异;6个分枝数QTL分别位于A03、A07、C01、C04和C06染色体,单个QTL解释5.95%~8.14%的表型变异。将156个拟南芥株高相关基因、10个拟南芥第1分枝高相关基因和148个拟南芥分枝数相关基因与QTL对应置信区间序列进行同源比较分析(E1E–20),分别找出了20个株高候选基因、3个第1分枝高候选基因以及12个分枝数候选基因。2个环境中在A07染色体上重复检测到的QTL置信区间检测到与株高相关的候选基因ATGID1B/GID1B和WRI1,A08染色体上重复检测到的QTL置信区间检测到SLR/IAA14和AXR2/IAA72个与株高相关的候选基因。在具有部分置信区间重叠的q2013FBH-C05-1和q2014FBH-C05-2区间均检测到第1分枝高候选基因PHT1;8,在A03和C06染色体上的QTL置信区间内,分别检测到4个分枝数候选基因,匹配E值介于0~3E–56之间。