生长分化因子-9(GDF9)基因多态性与邵伯鸡母系产蛋性状的关联性分析

为探讨生长分化因子-9基因(GDF9)的多态性与邵伯鸡母系产蛋性状的关系,本研究以中国农业科学院家禽研究所选育的216只邵伯鸡(Gallus domesticus)母系为材料,利用PCR-RFLP技术检测GDF9基因的SNPs,并分析基因多态性对邵伯鸡母系开产体重、开产日龄、开产蛋重、300日龄总产蛋数以及300日龄平均蛋重之间的关系。结果显示,在外显子2发现3个突变位点,G2051A位点检测到3种基因型GG、GA和AA,相关分析显示,GG基因型个体的开产体重和开产蛋重显著低于AA型个体(P0.05),而300日龄产蛋数显著高于AA型个体(P0.05);T2273C位点检测到2种基因型TT和TC,TT基因型个体与CT基因型个体的各性状差异均不显著(P0.05),C2336T位点检测到3种基因型CC、CT和TT,CT基因型个体的开产日龄显著早于CC与TT型个体(P0.05),其300日龄产蛋数显著高于CC型与TT型个体(P0.05)。3个位点的联合基因型GGCTCT对开产体重、开产日龄、开产蛋重、300日龄平均蛋重、300日龄产蛋数均有显著影响。研究结果提示,邵伯鸡母系GDF9基因的多态性与产蛋性状呈显著相关,可尝试用联合基因型GGCTCT为筛选邵伯鸡母系产蛋性状的分子标记辅助选择。     

兴义鸭LPL基因外显子8多态性与生长和肉质性状的关联性分析

脂蛋白脂酶（LPL）是动物脂质沉积和新陈代谢的关键酶,对生长和肉质发挥着重要作用。试验采用PCR-SSCP法和DNA直接测序技术相结合对兴义鸭LPL基因外显子8进行多态性检测,并分析其多态与生长和肉质性状的关联性。结果表明,在兴义鸭LPL基因外显子8首次检测到1个T1251C同义突变,产生三种基因型TT、TC和CC,2个等位基因T和C,基因型TT和等位基因T的频率分别为0．8077和0．8750,多态信息含量为0．1948,表现为低度多态,卡方（X2）检验表明T1251C位点的基因型分布在兴义鸭中未偏离Hardy-Weinberg平衡。最小二乘分析显示,TT基因型个体的宰前体重显著低于CC基因型（p〈0．05）,胸宽显著低于TC基因型白〈0．05）,推测等位基因C可能是兴义鸭生长性状的有利等位基因,可作为生长性状的一个标记性辅助选择位点。     

崂山奶山羊骨桥蛋白基因(OPN)部分片段多态性及其与生产性状的关联分析

骨桥蛋白(osteopontin,OPN)是一种分泌型糖基化磷蛋白,在介导骨组织细胞与骨基质的连接过程中发挥重要作用.为了加快奶山羊的遗传进展,为奶山羊生产性状的标记辅助选择提供理论依据,本研究利用DNA混合池技术和高分辨率熔解曲线分析技术,检测了崂山奶山羊(Capra hircus)泌乳母羊的OPN基因多态性,并采用最小二乘方法分析其与泌乳和生长性状之间的关联效应.在所有174只样本中共检测到2个SNPs,即位于第5内含子I355位点的C/T(以C/r表示)和第7外显子E341位点的C/T(以M/N表示),其多态信息含量(PIC)分别为0.2773和0.3267,其等位基因和基因型频率在育种场(F)和育种户(P)群体中的分布不均衡,I355位点的P群体偏离Hardy-Weinberg平衡状态(P＜0.05),其他均处于平衡状态(P＞0.05).在与泌乳性状的关联分析中,P群体除电导性状以外的所有性状表型值均极显著(P＜0.01)高于F群体;I355位点上,CC基因型个体的脂肪含量显著(P＜0.05)高于CT和TT基因型个体,灰分和冰点性状显著(P＜0.05)高于CT基因型个体；E341位点上,等位基因N为非脂肪物、乳糖率、乳密度、乳蛋白率、冰点以及灰分6个性状的有利等位基因,所有性状差异均不显著(P＞0.05).在与生长性状的关联分析中,F群体的体重和体长均极显著(P＜0.01)高于P群体；P群体的尻宽和尻长极显著(P＜0.01)高于F群体;I355位点上,TT基因型个体的体重极显著(P＜0.01)大于CC基因型个体；E341位点上,等位基因M为体高和胸围的有利等位基因,MM和MN基因型个体的体重和尻宽极显著(P＜0.01)高于NN基因型个体,MM基因型个体的体长极显著(P＜0.01)高于NN基因型个体,MM基因型个体的体高、胸围显著(P＜0.05)高于NN基因型个体.本研究发现OPN基因突变位点I355与乳中脂肪和碳水化合物的含量相关,突变位点E341与奶山羊的生长发育性状有显著的关联效应,可以作为奶山羊部分生产性状的分子遗传标记.     

南阳牛Gli3基因多态性及其与生长性状的相关性

Gli3基因是Gli-Kruppel家族中的一员,其参与的Sonic hedgehog信号通路在动物生长发育,特别是早期生长发育过程中有重要作用.利用PCR-SSCP和DNA测序技术研究了187头纯种南阳牛Gli3基因编码区4个位点(E4、E5、E6和E7)的多态性,发现E4和E5位点存在SSCP多态.对不同SSCP带型的对应片段进行了测序分析,共发现3个新的SNP多态位点(T123600C、T123696C和A128688G),其中第123600和第123696两个位点处于连锁状态.E5位点处于Hardy-Weinberg平衡状态,E4位点处于非平衡状态.不同基因型与生长发育性状的相关性分析显示,E4位点上,CC基因型个体的六月龄体重、胸围、坐骨端宽、日增重指标显著大于TT基因型个体(P<0.05),该位点有可能作为南阳牛早期生长性状标记辅助选择的标记之一.     

B细胞异位基因2（Btg2）多态性与河北小尾寒羊多脊椎性状的关联分析

利用直接测序、PCR-RFLP及dCAPS技术研究了河北小尾寒羊(Ouis aries)B细胞异位基因2的外显子3及3'-uTR上的多态性与河北小尾寒羊多脊椎性状的相关性.经测序结果分析,发现了A150G、C243T和A607G 3个单核苷酸多态性,3个位点的PCR-RFLP分析表明,150位点产生AA、AG和GG基因型;243位点产生CC、CT和TT基因型;607位点产生AA、AG和GG基因型.独立性卡方检测结果表明,150位点的不同表型个体基因型频率差异不显著(P>0.05),243位点的差异极显著(P＜0.01),607位点的差异呈显著水平(P<0.05);进一步对这3个位点进行单倍型分析,其独立性卡方检测表明单倍型在不同表型中差异显著(P＜0.05).其结果表明243位点、607位点以及单倍型GTA可能与小尾寒羊多脊椎性状有关.     

鸡ovr基因SNPs检测及其与蛋用性状的关联分析

为研究鸡卵细胞卵黄生成受体（Occyte vitellogenesis Receptor , OVR）对鸡产蛋性能及蛋品质的影响,本试验以六个鸡种（洪山鸡、江汉鸡、双莲鸡、郧阳大鸡、郧阳白羽乌鸡、海兰褐）的一代混交群体390个个体为研究材料,采用PCR-SSCP、PCR-RF-SSCP及测序的方法进行鸡ovr基因内含子单核苷酸多态性（SNPs）位点筛选,并与鸡群蛋用性状进行关联分析。结果表明,在鸡ovr基因中发现内含子2 T3967G,内含子7 C8099T、A8296G,内含子9 A8839T、G9084A共5个突变位点;其中内含子2 HinfⅠ突变位点与开产日龄、蛋壳厚度相关极显著（p<0.01）,与产蛋量、蛋重、蛋黄比例相关显著（p<0.05）;三种基因型中TT个体在开产日龄、平均产蛋量、蛋重、蛋黄比例等方面都优于其它基因型个体。本研究结果证实了其他学者研究的结论,即ovr基因对鸡的产蛋性能和蛋品质性状有重要的影响。     

肌肉生长抑制素基因(MSTN)外显子1的多态性及其与边鸡生长性状的关联分析

为了对边鸡生长性状的标记辅助选择提供基础资料,本研究采用PCR-SSCP技术检测边鸡(Gallusgallus)及3个对照鸡(G.gallus)群体(京海黄鸡、尤溪麻鸡和Arbor Acre鸡)肌肉生长抑制素(myostatin,MSTN)基因外显子1的单核苷酸多态性,并与边鸡的生长性状进行相关性分析。结果表明,在边鸡、京海黄鸡和尤溪麻鸡中都检测到6种基因型(AA、AB、BB、BC、AC和CC),而在Arbor Acre鸡中只检测到4种基因型(AB、BC、AC和CC)。总共检测到3个多态位点(G2100A、G2109A和C2244G)。在6～8和12周龄时,BB基因型个体的体重显著高于AA基因型个体(P<0.05)。在14周龄时,BB基因型个体的体重显著高于AA和AC基因型个体(P<0.05)。在16～18周龄时,BB基因型个体的体重显著高于其余5种基因型个体(P<0.05)。研究结果提示,MSTN基因可能是影响边鸡生长性状的一个主效基因或是与之存在紧密遗传连锁的一个标记。     

鸡卵细胞卵黄生成受体基因(ovr)SNPs检测及其与蛋用性状的关联分析

以6个鸡(Gallus gallus)品种混交群体390个个体为研究材料,采用PCR-SSCP、PCR-RF-SSCP及测序的方法进行鸡卵细胞卵黄生成受体(occyte vitellogenesis receptor,ovr)基因内含子单核苷酸多态性(SNPs)位点筛选,并与鸡群蛋用性状进行关联分析.结果表明,在鸡ovr基因中发现内含子2T3967G,内含子7C8099T和A8296G,内含子9A8839T和G9084A共5个突变位点;其中内含子2HinfⅠ突变位点与开产日龄和蛋壳厚度相关极显著(P＜0.01),与产蛋量、蛋重和蛋黄比例相关显著(P＜0.05);3种基因型中订个体在开产日龄、平均产蛋量、蛋重、蛋黄比例等方面都优于其它基因型个体.研究结果证实了ovr基因对鸡的产蛋性能和蛋品质性状有重要的影响.     

鸡解耦联蛋白基因型与活性氧含量、初生重的相关性分析

为了研究解耦联蛋白基因(uncoupling protein,UCP)对鸡(Gallus gallus)初生重及活性氧含量的影响,本实验通过对3个品种鸡初生重、UCP C353T多态位点基因型以及肌肉组织活性氧(ROS)含量的测定,发现丝羽乌鸡ROS值显著低于白莱航、寿光鸡,UCP TT基因型ROS值显著高于CT和CC基因型,而ROS含量与雏鸡初生重之间存在着正向的相关性(r=0.5011),UCP TT基因型的初生重显著高于CT和CC基因型。实验结果揭示了鸡UCP基因型对初生重性状具有选择效应。     

鸡DGAT2基因第7外显子多态性与生产性能的关联

二脂酰甘油酰基转移酶(diacylglycerol acyltransferase,DGAT)是催化真核生物甘油三酯合成最后一步反应的关键酶和限速酶,包括DGAT1和DGAT2两种.DGAT2对调节脂肪代谢、脂类在组织中的沉积及生长发育发挥重要作用.为研究鸡(Gallus gallus)DGA T2基因遗传多态性及其与生产性能的相关性,本研究以固始鸡×安卡鸡杂交F2资源群体(n=860)为研究材料,利用聚合酶链式反应限制性片段长度多态性(polymerase chain reaction-restriction fragment length polymorphism,PCR-RFLP)技术检测DGAT2基因的多态性,并分析多态性与生长性状、肉质性状、屠体性状、血液生化指标和肌纤维性状之间的关联性.结果显示,DGAT2基因第7外显子g.13955位置存在一个同义突变位点(C→T),PCR扩增产物被限制性酶Taq Ⅰ酶切消化后显示出CC、CT和TT三种不同基因型,基因型频率分别为0.49、0.48和0.03,等位基因A和B的频率分别为0.73和0.27.相关性分析显示,固始鸡×安卡鸡F2代个体初生重,2、4周龄体重、4、8周龄体尺指标及肌内脂肪含量在不同基因型之间差异显著(P＜0.05),CC基因型多数性状值显著高于TT基因型,对其他指标在统计学上无显著影响(P＞0.05).由以上结果可以推测,鸡DGAT2基因g.13955C＞T与生长发育有关,且C等位基因为优势基因,有望成为家禽品种选育的潜在DNA分子标记.     

Growth of Crop and Weeds in Growth Chambers and Outdoors

The early growth of spring barley (Hordeum ulgare L.), Brassica rapa L. ssp. oleifera (DC.) Metzger, Stellaria media (L.) Vill. and Viola arvensis Murray in growth chambers and in shading cages outdoors at different irradiance levels was compared. Leaf area and shoot dry weight were lower outdoors than in growth chambers at similar irradiance and temperature. A simulation model with temperature and irradiance responses derived from growth-chamber experiments was used to test whether outdoor growth could be estimated properly. The correlations of the regressions between simulated and measured values of leaf area index (LAI) and shoot dry weight were high. However, with some exceptions, overestimations occurred, more for shoot dry weight than for LAI, and more for 100% daylight than for lower irradiance. The reasons for this are discussed.     

不同性别河北柴鸡早期生长规律及其生长曲线拟合

本研究运用Logistic、Gompertz和Bertalanffy三种非线性模型对不同性别河北柴鸡早期生长规律和生长曲线进行分析及拟合比较。结果表明,3种曲线模型拟合度均达到0.99以上,但Gompertz曲线模型在拟合度和预测极限生长量、拐点周龄和最大周增重等方面相对较好。进一步分析表明,河北柴鸡公鸡的极限体重和拐点体重均高于母鸡,拐点周龄性别间差异不大,公鸡最大周增重与实际观测值接近。本文有助于了解不同性别河北柴鸡各自的生长模式及其对营养、环境的需求,为开展规模化饲养提供参考。     

三种植物生长调节剂对大豆生长发育及产量的影响

为提高单作大豆产量,本研究以大豆品种南豆12为材料,分别探究了不同浓度的3种植物生长调节剂拌种对大豆田间出苗的影响,及叶面喷施对大豆生长发育、产量及品质的影响。结果表明,不同浓度的褐藻胶寡糖、壳寡糖、冠菌素拌种均能提高大豆的田间出苗率,而叶面喷施均能提高大豆的株高与茎粗,褐藻胶寡糖和冠菌素拌种可增加大豆分枝数,壳寡糖拌种则减少了大豆分枝数。3种植物生长调节剂均能在一定程度上提高单株粒数与百粒重,进而提高大豆产量,同时还可提高大豆粗蛋白含量,降低粗脂肪酸含量以及满粒期大豆籽粒中可溶性糖与还原性糖的含量。此外,叶面喷施植物生长调节剂并不会影响收获子代大豆的萌发。褐藻胶寡糖、壳寡糖、冠菌素拌种推荐每公斤大豆使用100 mL植物生长水溶液拌种,浓度分别为25、100、0.05 mg·L^-1;叶面喷施的推荐使用量分别为50、50、0.01 g·hm^-2。 本研究结果为大豆丰产栽培提供了理论依据。     

Biochar Application Promotes Growth Parameters of Soybean and Reduces the Growth Difference

Biochar is derived from the pyrolysis of biomass, and when buried in soil, can act as a long-term soil carbon store. Evidence suggests that biochar can improve soil fertility and crop production in some circumstances. However, the potential for promoting crop growth in agroecosystems is poorly understood, with different reports of soil properties following biochar application. Therefore, this study aims to investigate the spatial variability of soybean growth parameters in different biochar application rates and the reasons for the results obtained. The study used field plots with five biochar application rates (0, 20,40, 80, and 160 t·ha^?1). There were 15 field plots in total and the trial was fully randomized with three replications. The biochar was mixed into the topsoil (0–20 cm depth) before the soybean was sown. Soybean growth parameters were determined during the flowering–podding phase. The results showed that biochar not only improved the growth parameters of soybean, but also reduced growth differences in the same treatment, and higher biochar application rates would result in a larger effect size in a certain range (0–103.4 t·ha^?1). The leaf area in the no biochar treatment showed moderate variation, whereas the growth parameters (height, stem diameter, and leaf area) showed weak variation in the other biochar treatments; and the growth parameters, when the soybean were subjected to the biochar treatments, had moderate spatial dependence. In addition, the introduction of geostatistical theory can provide a theoretical foundation for further studying biochar–soil–crop system and the spatial variability of soybean growth and their relevance.     

Soil Micronutrients and Citrus Growth

By using nutritional diagnosis of citrus leaves and determining soil micronutrients,the relationship between soil micronutrients and citrus growth in southern China has been studied.Studies showed that there was a significant positive correlation between available micronutrients (such as Zn,Mo,Cu)in the soil and the corresponding nutrients in citrus leaves.Thus,one can roughly learn of the sufficiency or deficiency of certain nutrients in soils by analyzing citrus leaves.Rational spray of Zn B or Mo fertilizer not only improved citrus yields but also increased the total sugar of Satsuma mandarin and of Xinhui orange by 2.9 and 17.2% respectively compared with the control.Spraying Mo fertilizer increased the vitamin C content of Satsuma mandarin juice by 4.7%-8.4%,maturated fruits 7-10 days earlier and gave the peel a brighter color.The ultramicroscopic characteristics of Zn-deficient citrus leaves were investigated under an electron microscope.Results showed that the Zn-deficient leaf cell was characterized mainly by poor cytoplasm,endoplasmic reticula and ribosomes and by big starch grains in the chloroplast.As a result of spraying Zn fertilizer the structure of the cell returned to normal,the cytoplasm became rich and the amount of chloroplast increased.There also appeared a great deal of multiform endoplasmic reticula,thus promoting the photosynthesis of Zn-deficient plants.This provides a cytologico-theoretical basis for fertilization of high-yielding citrus trees.     

Citrus Growth and Rhizosphere Properties

Fifteen citrus varieties (four varieties of limes/lemons, three varieties of mandarins, and eight varieties of sweet oranges) were tested in a row-to-row multireplicate field experiment on Typic Rhodustalf. Pre-bearing growth behavior of different citrus varieties showed a significant difference (P ≤ 0.05) with respect to canopy volume (1.221 m³ with Bearss lemon and 0.220 m³ with Cara Cara Navel) governed by changes in different rhizospheric properties (soil-available nutrients, soil microbial population, and soil microbial biomass nutrients). Response in canopy volume was more governed by soil microbial biomass nutrients [carbon (C_mic), nitrogen (N_mic), and phosphorus (P_mic)] followed soil microbial population and soil available nutrients in decreasing order. Indices developed through diagnosis and recommendation integrated system further helped in partitioning interrhizosphere nutrient deficiencies. These studies suggested that (i) biological properties of rhizosphere soils of limes and lemons were of much superior quality and (ii) rhizospheric biological properties are transformed according to plant species and variety.     

Modelling Spring Growth of Timothy and Meadow Fescue by an Expolinear Growth Equation

The applicability of an expolinear growth equation for describing dry matter yield was investigated in seven field experiments for spring growth of timothy (Phleum pratense L.) and meadow fescue (Festuca pratensis Huds.) under two levels of N application. The equation was expanded by a growth index (GI) correcting for variations in radiation, temperature and plant-available soil moisture, and an ageing function describing the decrease in growth rate caused by advance in phenological development. The field sites covered a wide range of climatic conditions and the yield was recorded at five phenological stages from leaf stage to anthesis. The expansion of the equation appeared to be adequate for a combined analysis of the dry matter yield in meadow fescue and timothy. The estimated maximum growth rate during the linear phase (C _m) did not differ significantly between species. C _m increased with higher N application. It was concluded that C _m of the expanded model represented a potential rate, whereas the relative growth rate of the exponential phase (R _m) could not be considered as a potential rate. It varied more among locations and years, e.g. it was strongly affected by the length of the period from growth onset to the start of the linear phase.     

Interaction Between Calcium Concentration and Growth Irradiance on Photosynthesis and Growth of Temperate Lettuce in the Tropics

ABSTRACT

Temperate lettuce (Lactuca sativa L.) was grown in the tropics under 100% (high light), 70% (medium light), and 40% (low light) of prevailing solar radiations. Their root zones were maintained at 25°C, while the shoots were exposed to hot ambient temperature. Three calcium (Ca) concentrations: ?25% Ca (minus Ca), control (Ca) and +25% Ca (plus Ca) were supplied to the plants under each growth irradiance. Plants grown at the plus Ca under high light had the highest productivity, largest root system, highest photosynthetic capacity and highest Ca concentration. Grown at the minus Ca under low light they had the lowest values of these parameters. However, highest and lowest chlorophyll concentrations were found in plants grown at the plus Ca under low light and at the minus Ca under high light, respectively. When grown at the plus Ca under low light, plants transported higher portion of the absorbed Ca to the shoots.     

植物根际促生菌促进小麦生长及提高其抗旱性的研究进展

干旱胁迫是影响小麦生长发育与产量形成最主要的非生物胁迫因子,近年来化肥的过量使用及全球气候变化产生的不利影响,导致小麦在生长过程中受到的干旱胁迫危害日趋严重。植物根际促生菌(PGPR)不仅可以协助小麦提高养分利用率,促进其生长发育,还能够通过自身作用或产生多种代谢产物协助小麦抵御干旱胁迫。本文归纳总结了PGPR促进小麦生长及提高其抗旱性的研究进展,为利用PGPR提高小麦促生抗旱的研究奠定了理论基础。     

Cadmium Effects on Sunflower Growth and Photosynthesis

The objective of this work was to evaluate the effects of cadmium (Cd) exposure on sunflower (Helianthus annuus L.) plant growth, chlorophyll content, and fluorescence. Sunflower plants were exposed to different concentrations of Cd (0, 5, 50, and 500 μ M) for 21 d. Growth parameters (organ length, fresh and dry weights) were determined and results compared with two parameters associated with photosynthesis degradation: chlorophyll content and fluorescence (an easy and non-destructive method). Exposure to Cd significantly decreased growth by decreasing shoot and root lengths and their fresh and dry weight. Cadmium also decreased significantly chlorophyll content and fluorescence efficiency in all treatments. Chlorophyll a (chl a) and chl b contents showed a significant correlation with chlorophyll fluorescence (F_v/F_m ratio). The EC₅₀ values showed that the roots' length was the most sensitive endpoint in this study, followed by the roots' and shoots' weight endpoints. Also, chl b showed higher sensitivity to Cd contamination than chl a. These data show that in complement to growth parameters, the use of photosynthetic parameters provides helpful information on plant response to Cd exposure.