新生仔猪对外源抗体的吸收及乳糖对其吸收的影响

选择48头自然分娩、3～4胎、初生重1.25～1.5kg 的大白猪(♂)×内蒙黑猪(♀)杂交F1 代新生仔猪参试。其中24头于出生后的6小时之内用人工瓶哺的方法分别饲喂0(对照组)、1、2、3、4、8g的外源PIgG ;另外24头出生后的18小时之内分别饲喂不同含量的乳糖 ,然后开始饲喂一定浓度的外源PIgG ,分别研究了生新仔猪对外源PIgG吸收及乳糖对其吸收的影响。研究结果表明 ,仔猪出生后没有吸吮初乳之前其血清中的IgG含量甚微 ,为(0.12±0.058)mg/ml;随着饲喂浓度的增加新生仔猪对外源PIgG的吸收也增加(P<0.05) ,到出生后12小时 ,仔猪血清中的IgG含量达到峰值 ,随后逐渐下降 ,下降趋势与自然哺乳仔猪血清IgG的消长规律相似。若仔猪出生后仅喂给不含PIgG的人工初乳 ,则仔猪血清中的IgG水平在出生后的72小时之内一直保持刚出生时的水平(P>0.05) ,表明在此阶段内仔猪还没有合成自身IgG的能力。仔猪出生后饲喂8g 外源PIgG ,其血清中的IgG峰值能达到22.18mg/ml ,这一值与自然哺乳情况下的峰值相比相差甚大。乳糖强烈抑制新生仔猪对外源PIgG的吸收(P<0.05) ,给仔猪饲喂10g乳糖后与对照组(水)比较 ,仔猪对外源PIgG的吸收将减少45.31 % ,而喂50g乳糖则减少92.02 %。在本试验条件下 ,乳糖浓度对新生仔猪吸收PIgG的抑制曲线为典型     

日本甜柿开花习性的调查研究

为了给日本甜柿栽培技术提供理论依据和制定科学的管理措施提供参考,以提高贵州柿树的管理水平。连续3年(2012—2014)对日本甜柿开花习性进行了调查研究。结果表明:结果母枝直径直接影响不同大小直径结果母枝的百分率,直径以7.1~8.0mm为最高,其次是直径为6.1~7.0mm,再次是直接5.1~6.0mm;结果母枝直径也直接影响结果母枝萌芽率、开花枝长度、直径、花节位百分率、花序种类、花序量、花种类和花量等内容,以处理4(直径为6.1mm≤d7.0mm)的效果最好,其次是处理3(直径为5.1mm≤d6.0mm)的效果,再次是处理5(直径为7.1mm≤d8.0mm)的效果;结果母枝长度直接影响结果母枝萌芽率、结果母枝抽开花枝长度、直径、花节位百分率、抽开花枝开一顶花两侧花花序量、一顶花一侧花花序量、一顶花花序量、花序总量、开顶花量、侧花量和总花量等内容,结果母枝越长,其效果越好;结果母枝部位直接影响结果母枝抽开花枝长度、直径、花节位百分率、抽开花枝开一顶花两侧花花序量、一顶花一侧花花序量、一顶花花序量、花序总量、开顶花量、侧花量和总花量等内容,在结果母枝的越上部,其效果越好。培养结果母蔓直径大小时,以直径6.1~7.0mm为主,配合直径为5.1~6.0mm和7.1~8.0mm;培养结果母枝长度以长的结果母枝为主,配合较长的结果母枝;结果母枝着生部位,以母枝顶芽结果母枝为主,配合次芽结果母枝。     

Detecting and estimating segregation distortion and linkage between glufosinate tolerance and blackleg resistance in Brassica napus L.

Summary The segregation and linkage between glufosinate (transgenes ‘Rf3’ and ‘T177’) and blackleg resistance genes in canola (Brassica napus L.) were assessed using F₁ microspore-derived doubled haploid (DH) populations from four crosses including reciprocals, two involving the transgene ‘Rf3’ and the other two involving the transgene ‘T177’. To relax the assumption of no segregation distortion required for the conventional analysis of segregation and linkage, we employed Bailey's analysis that allows detecting segregation distortion at linked loci. The significant departures from the 1:1 segregation were detected in the crosses involving the transgene ‘T177’ but not in the crosses involving the transgene ‘Rf3’. The apparent deficit of the herbicide tolerant DH lines in the crosses with the transgene ‘T177’ is likely due to differential selection against the gametes carrying ‘T177’ during microspore culture. The linkage was strong between blackleg resistance and the transgene ‘Rf3’ but weak or absent between blackleg resistance and the transgene ‘T177’, suggesting that the two transgenes are probably inserted into distant regions of the genome. The observed linkage offers an opportunity to develop new canola cultivars with both glufosinate tolerance conferred by transgene ‘Rf3’ and blackleg resistance.     

Resynthesis of Brassica napus L. for self-incompatibility: self-incompatibility reaction, inheritance and breeding potential

Self-incompatibility (SI) in Brassica has been considered as a pollination control mechanism for commercial hybrid seed production, and so far has been extensively used in vegetable types of Brassicas. Oilseed rape Brassica napus (AACC) is naturally self-compatible in contrast to its parental species that are generally self-incompatible. Introduction of S-alleles from its parental species into oilseed rape is therefore needed to use this pollination control mechanism in commercial hybrid seed production. Self-incompatible lines of B. napus , carrying SI alleles in both A and C genomes, were resynthesized from self-incompatible B. oleracea var. italica (CC) cv.'Green Duke' and self-incompatible B. rapa ssp. oleifera (AA) cv. 'Horizon', 'Colt' and 'AC Parkland'. All resynthesized B. napus lines exhibited strong dominant SI phenotype. Reciprocal cross-compatibility was found between some of these self-incompatible lines. The inheritance of S-alleles in these resynthesized B. napus was digenic confirming that each of the parental genomes contributed one S-locus in the resynthesized B. napus lines. However, the presence of two S-loci in the two genomes was found not to be essential for imparting a strong SI phenotype. Possible use of these dominant self-incompatible resynthesized B. napus lines in hybrid breeding is discussed.     

Wheat starch biosynthesis

Starch biosynthesis in plants involves the concerted action of a numberof enzymes, including ADPglucose pyrophosphorylase, starch synthases,branching enzymes and debranching enzymes. We report on the cloningand characterisation of genes encoding these enzymes from wheat and ontheir chromosomal locations. The prospects for manipulating wheat starchstructure and functionality using these genes is discussed.     

Evaluation of Early Generation Testing in Chickpea1)

Inter-generation correlations between F₂-F₃, F₂-F₄ and F₃-F₄ in six crosses of chickpea were calculated by using individual plant/progeny means. In general, correlation values in case of plant height, seeds per pod and 100-seed weight were higher between F₃ and F₄ than those between F₂ and F₃ and F₂ and F₄. However, inter-generation correlations were mostly non-significant in case of pods per plant and grain yield. These results clearly show that selection in F₃ can be fruitful for seeds per pod and 100-seed weight. However, selection for pods per plant and grain yield in early generations may not show any relationship with later generation performance for these traits.     

Introgression of alleles of the isozymic locus glucosephosphate isomerase-2 (GPI-2) from the CC genome of Brassica carinata to the CC genome of Brassica alboglabra and their independent segregation from seed colour

A yellowish brown‐seeded Brassica alboglabra was resynthesized from a (B. alboglabra×Brassica carinata) ×B. alboglabra cross, followed by self‐pollination. The resynthesized B. alboglabra lost the allele of the isozymic locus glucosephosphate isomerase‐2 (GPI‐2) from natural B. alboglabra, which was replaced by an allele from the corresponding genome in B. carinata. A simple Mendelian segregation of these two alleles was observed in the F₂ population of a natural × resynthesized B. alboglabra cross. Furthermore, these two alleles segregated independently from the seed colour.     

不同N水平的富营养化水体中经济植物净化能力比较研究

为建立净化富营养化水体的生态工程，本试验选择水芹、水蕹菜、韭菜、葱、黄花菜、芹菜等6种经济植物，研究了各种植物的净化能力及其生物学特性。结果表明：每种经济植物对水体总氮、总磷均有一定的去除作用，特别是水芹和水蕹菜，其在试验的20d内，对总氮、总磷的去除百分率分别为89．5％，98．2％；同时还对6种经济植物引起水体总氮浓度下降与时间关系作回归分析，结果表明随着处理时间的延长，水体中总氮浓度呈负指数形式衰减。本文还对在植物处理过程中，水中Chla、BODs和COD的变化进行了观测。研究表明，在高N水平的富营养化水中除水芹和水蕹菜外，Chla、BOD。和COD随处理时间的延长而下降，但在韭菜和葱处理过程中，水中腥味加重。各项指标综合分析表明，在不同N水平的富营养化水体中，水蕹菜处理效果最好，水芹次之，黄花菜和芹菜居中，韭菜最差。