湖北白猪Ⅵ系主选性状的遗传趋势分析

用公畜分组带亲缘关系的混合模型ＢＬＵＰ法对湖北白猪Ⅵ系的主选性状、日增重和背膘厚进行了遗传趋势分析，结果表明：在６ 个世代的继代选育中，日增重的群体遗传趋势为７１．０１３５ ｇ，呈逐代上升趋势；背膘厚群体遗传趋势为－０．００９５ ｃｍ ，呈逐代下降趋势。但是，通过世代的ＥＴＡ变异范围的波动性来看，其遗传潜力还未能充分表现，有待于进一步提高。通过公畜血统组间效应分析和日增重与背膘厚两性状的ＥＴＡ、ＷＡＴＡ相关关系分析得出，随着Ⅵ系选育的进一步深入，提高日增重，有使瘦肉率降低的危险。

数量性状主要基因随机效应的分析

数量性状主基因在不同环境或遗传背景中表现随机效应。本文提出数量性状基因随机效应分析的试验设计和统计模型，以及对基因的分离比、平均效应和随机方差进行假设测验的方法．所述方法可用于借助标记基因对数量性状基因效应作类似分析．

黄羽肉鸡毛囊大小与主翼羽性状遗传参数估计

研究旨在估测黄羽肉鸡毛囊大小和羽毛性状的遗传参数,为屠体外观性状的选育提供理论依据。试验以广东温氏南方家禽育种有限公司的N204品系为素材,测定腿部毛囊大小(LFS)、背部毛囊大小(BFS)、第五根主翼羽长度(FL)、主翼羽羽根直径(FCD)和87日龄活重(87BW),计算腿部毛囊大小指数(LFSI)和背部毛囊大小指数(BFSI),采用单性状动物模型计算上述性状的遗传参数,并评估这些性状间的遗传和表型相关的显著性。结果显示:LFS和BFS差异极显著(P<0.01);公母间除BFS外,其余性状差异均达极显著水平(P<0.01);LFS、LFSI、BFS、BFSI、FL、FCD和87BW的遗传力分别为0.336、0.465、0.237、0.315、0.606、0.370和0.271;毛囊大小与主翼羽性状没有显著遗传相关关系(P>0.05),但与87BW有较高的遗传和表型相关性,遗传相关系数为-0.402~-0.398,表型相关系数为0.129~0.192。结果表明,通过FL、FCD间接对LFS、BFS选择不可行,若对毛囊性状进行直接选择,利用LFSI和BFSI作为选择指标更容易获得遗传进展。

啤酒大麦F_1和F_2代主穗性状间的遗传变异研究

用GriffingⅡ（1965）等对6个啤酒大麦亲本及其配制15个组合的F1、F2代主穗性状进行遗传变异、配合力及相关分析表明：（1）主穗性状的遗传力F1代明显高于F2代，亲本性状的遗传力、遗传变异系数与F2呈高度正相关，但与F1相关系数相对较小。（2）株高、实粒数、穗粒重，主要受基因加性效应控制，但其间的差异F1大于F2。各性状的配合力因亲本、组合、世代而异，同亲本F1与F2间的一般配合力呈高度正相关，但特殊配合力偏低；澳、欧、亚洲型品种杂交的F1性状特殊配合力较高，F2亚洲型品种间也存在高配合力组合。（3）F2代实粒数与穗粒重的变异系数明显高于F1，但株高相近。

种植密度与蓖麻主穗性状及种子性状的相关性

【目的】探明种植密度与蓖麻主穗性状及种子性状的相关性,为合理制定蓖麻种植密度提供参考。【方法】通过蓖麻不同种植密度试验,研究蓖麻主穗性状和种子性状对不同密度的响应。【结果】蓖麻种植密度与主穗结蒴果序节位数、主穗结蒴果序节位百分率、主穗蒴果数、主穗种子产量、主穗种粒数和种子长度等指标存在显著相关性(P<0.05);主穗种子产量与主穗结蒴果序节位数、主穗结蒴果序节位百分率、主穗蒴果数、主穗蒴果单果重和主穗种粒数等指标存在极显著相关性(P<0.01);主穗种粒数与主穗结蒴果序节位数、主穗结蒴果序节位百分率、主穗蒴果数和主穗种子产量等指标存在极显著相关性(P<0.01),与主穗蒴果单果重存在显著相关性(P<0.05)。蓖麻种植密度与主穗性状和种子性状指标的回归方程符合二次曲线规律。【结论】一定范围内,蓖麻种植密度越大,主穗结蒴果序节位百分率、主穗结蒴果节位数、主穗蒴果数、主穗种粒数和种子长度等指标越大,主穗宽横径、主穗种子产量指标也一定程度地增加。

甘蓝型油菜多主花序性状的表型特点与遗传分析

为改良油菜株型以提高产量和适应机械化,分析多主花序油菜的表型特点和遗传规律,利用1个甘蓝型油菜多主花序突变体和1个单主花序普通材料,通过扫描电镜观察甘蓝型油菜多主花序材料顶端分生组织发育过程,认为多主花序性状的形成与顶端分生组织的异常发育有关。对F1、RF1以及分离群体做表型鉴定,结果表明:多主花序性状在两个供试亲本材料间存在1对显性基因的差异,无细胞质效应。利用油菜60K SNP芯片结合分子标记技术,初步构建多主花序基因MI的遗传连锁图谱,两侧最近标记L04-2和L06-14与目标基因的遗传距离分别为4.4 cM和9.3 cM,物理距离为2.5 Mb。

胜利白猪近交程度的分析及对主选性状的影响

胜利白猪Ⅰ、Ⅱ系经过7、8个世代的继代选育,群体平均近交系数分别达到8.36%和8.57%,随着群体纯合度的提升对主选性状有不同程度的影响。对于遗传力(h2)低的性状,如产仔数、产活仔数的影响不大,大体保持在1世代的性能水平。对于遗传力(h2)中、高的性状,如后备猪的生长速度和同胞育肥性能等性状,则随世代选育均有明显的改进,改进幅度在10%以上,显示适度近交没有影响世代选育的效果。杂交试验证明,杂交优势也未因群体近交系数的增大受到影响。

基肥施用量与蓖麻主穗性状及种子性状指标的相关性

为探讨影响蓖麻主穗性状及种子性状的因素,以诺泰克复合肥作为基肥,设置7个基肥施用量(2100~6300 g/区)处理区,历经3年(2019—2021年),研究了蓖麻主穗性状和种子性状指标对基肥施用量的反应。结果显示:(1)蓖麻主穗蒴果数量、主穗种子产量和主穗种粒数量等指标随着基肥施用量的增加,呈先增加后降低的趋势,在4200 g/区的效果最好,其次是4900 g/区的效果,以后是5600 g/区的效果。(2)基肥施用量与主穗结蒴果序节位数量、主穗蒴果数量和主穗种粒数量等指标之间存在显著差异(P<0.05);主穗种子产量与叶片长度和叶柄长度之间存在极显著差异(P<0.01),与叶片质量之间存在显著差异(P<0.05)。(3)拟合的回归方程符合二次曲线规律;基肥施用量与蓖麻主穗直径、主穗结蒴果序节位数量、主穗结蒴果序节位百分率、主穗蒴果数量、主穗种子产量和主穗种粒数量等指标之间存在极显著差异(P<0.01),与主穗蒴果单果质量和种子长度等指标之间存在显著差异(P<0.05)。基肥施用量对蓖麻主穗结蒴果序节位数量、主穗蒴果数量和主穗种粒数量等指标增加幅度的影响最大,其次是对主穗结蒴果序节位百分率、主穗蒴果单果质量和种子产量等指标增加幅度的影响,以后是对主穗蒴果序节位数量、种子百粒质量和种子长度等指标增加幅度的影响,最后是对种子宽横径和种子厚横径等指标增加幅度的影响。

典范性状的决策分析

采用通径分析的决策分析方法,对典范性状建立了通径分析化模型,进而完成了对其的决策分析; 给出了判断典范性状中主载性状、限制性状及中间性状的方法,以便于育种者根据个体的性状表现来选择,达到对 Fi选择而期望得到的遗传进展。

利用辅助性状提高半同胞测验的准确度

利用公畜半同胞个体包括主性状在内的若干个相关性状的表型值构造一个公畜指数，并导出利用该指数对公畜主性状进行选择的准确度．证明采用辅助性状时，半同胞测验的准确度总是高于未采用辅助性状时的准确度．数值计算结果表明，当各辅助性状和主性状的表型和遗传相关符号相反时，辅助性状的使用对选择准确度的提高最为显著．当辅助性状只有一个时，还导出一个计算给定准确度下每一公畜所需度量的半同胞个体数的公式．最后在一些简化条件下讨论辅助性状数目对选择准确度提高的影响．

硒都黑猪新品种综合选择指数的制定

[目的]为保持硒都黑猪新品种亲本肉质优良、环境适应性好的优良特性,提高繁殖和生长性能,[方法]以总产仔数、达90 kg体重日龄、90 kg体重活体背膘厚和肌内脂肪含量为4个主选性状,制定硒都黑猪新品种选育的综合选择指数。[结果]经过6个世代的选育,各选择性状基本达到了育种目标,总产仔数、达90 kg体重日龄、90 kg体重活体背膘厚的遗传改进量分别为1.18、-29.2和-5.74,总产仔数和90 kg体重背膘厚实际遗传改进量较预期改进量分别提高10.49%和1.77%。[结论]结果表明,根据育种目标制定综合选择指数的方案可行,可应用于硒都黑猪育种实践。

多个主成分性状的综合优化研究

考虑育种目标的要求,对多个独立的主成分性状进行综合优化,建立了综合主成分性状的数学模型.综合主成分性状是s个表型方差(遗传方差)最大的主成分性状在育种目标约束下表型方差(或遗传方差)极大化下的线性组合,作为育种指标,选择效果好,预见性强.

Correlation and Principal Component Analysis on Main Agronomic Traits of New Waxy Corn Varieties

[Objective] This study was conducted to provide certain theoretical reference for the comprehensive evaluation and breeding of new fresh waxy corn vari- eties. [Method] With 5 good fresh waxy corn varieties as experimental materials, correlation analysis and principal component anatysis were performed on 13 agronomic traits, i.e., plant height, ear position, ear weight, ear diameter, axis diameter, ear length, bald tip length, ear row number, number of grains per row, 100-kernel weight, fresh ear yield, tassel length, and tassel branch number. [Result] The principal component analysis performed to the 13 agronomic traits showed that the first three principal components, i.e., the fresh ear yield factors, the tassel factors and the bald top factors, had an accumulative contribution rate over 87.2767%, and could basically represent the genetic information represented by the 13 traits. The first principal component is the main index for the selection and evaluation of good corn varieties which should have large ear, large ear diameter but small axis diameter, i.e., longer grains, larger number of grains per ear, higher, 100-grain weight and higher plant height. As to the second principal component, the plants of fresh corn varieties are best to have longer tassel and not too many branches, and under the premise of ensuring enough pollen for the female spike, the varieties with fewer tassel branches shoud be selected as far as possible. From the point of the third principal component, bald tip length affects the marketing quality of fresh corn, and during fariety evaluation and breeding, the bald top length should be control at the Iowest standard. [Conclusion] The fresh ear yield of corn is in close positive correlation with ear weight, 100-grain weight, ear diameter, number of grains per row and ear length, and plant height also affects fresh ear yield.

Analysis on the Combining Ability and Heritability of Main Agronomic Traits of Hybrid Glutinous Sorghum

Using 3 sterile lines and 12 restorer of glutinous sorghum as experimental materials,36 hybrid combinations（3×12 NCⅡ） were designed to analyze the combining ability and heritability of six main agronomic traits,including plant height,panicle length,growth period,1 000-grain weight,per panicle grains and per panicle grain weight.The results showed that except per panicle grain number all other five agronomic traits have remarkable or extremely remarkable general combining ability and specific combining ability.Six agronomic traits were found to be control by additive genetic effect.Most of these agronomic traits are more easily influenced by restorers than sterile lines,suggesting that more attention should be paid to select restores in hybrid glutinous sorghum breeding.The narrow-sense heritability of these agronomic traits were in order growth period plant height per panicle grain weight panicle length 1 000-grain weight per panicle grains.

家畜分子育种研究进展

本文综述了家畜 (猪 )的主效数量性状基因座育种和转基因育种的研究进展。主要包括构建基因图谱 ,并据此定位主效数量性状基因座或与之连锁的 DNA标记 ;通过转基因技术来改良家畜重要经济性状或生产生化制剂或进行器官移植的研究。

Statistic Morphology Difference between Male and Female Individuals of Paramisgurnus dabryanus Sauvage

[Objective] The aim was to compare the morphology difference between male and female individuals of Paramisgurnus dabryanus Sauvage. [Method] The comparison of 10 morphological characteristics between male and female individuals of P. dabryanus was conducted with principal component analysis and t-test methods. [Result] The results of t-test indicated that three of 10 morphological characteristics showed extremely significant difference（P0.01）and one of 10 morphological characteristics was significantly different（P0.05）. Principal component analysis revealed four principal components,the contribution rate of which was 31.151%,18.844%,12.324% and 10.169%,respectively. The cumulative contribution rate had reached 72.487%. The morphological variations between male and female individuals were not significant,which was consistent with that of t-test. [Conclusion] The result in this study had provided theoretical basis for the breeding of P. dabryanus.

Principal Component Analysis on Traits Related to Lodging Resistance of Plateau Japonica Rice

Objective] This study was conducted to investigate the main factors affect-ing the lodging resistance of plateau japonica rice. [Method] Twenty agronomic traits related to lodging resistance of plateau japonica rice were analyzed by principal component analysis and correlation analysis among 26 varieties/lines of plateau japonica rice. [Result] The lodging resistance of the 26 varieties/lines had great dif-ference among different agronomic traits. Plant height, and wal thickness of the 4th, 3rd and 2nd internodes under the panicle had the most important influence on lodging resistance, while the diameter of the 3rd, 2nd, 4th, 1st nodes under the panicle, length of the 4th and 3rd internodes under the panicle, wal thickness of the 1st internode under the panicle had less influence. The other nine agronomic traits of rice culm did not affect or indirectly affected lodging resistance through above-mentioned agro-nomic traits. Lodging resistance had significant correlations with plant height, length of the 4th and 3rd internodes under the panicle, wal thickness of the 1st, 2nd, 3rd and 4th internodes under the panicle and diameter of the 1st, 2nd, 3rd and 4th node sunder the panicle, had insignificant correlations with panicle length, panicle weight, length of the 1st and 2nd internodes under the panicle, diameter of the 1st, 2nd, 3rd and 4th internodes under the panicle, diameter of the 5th node under the panicle. [Conclu-sion] More attention should be paid to the main factors affecting lodging resistance in breeding to improve lodging resistance of plateau japonica rice.

普通丝瓜始雌花节位遗传分析

选用始雌花节位有差异的普通丝瓜品种配制‘五叶香丝瓜’ב短圆筒丝瓜’(L1×L2)和‘短圆筒丝瓜’ב蛇形丝瓜’(L2×L3)2套组合,通过调查P1、P2、F1、B1、B2和F2植株的始雌花节位,利用主基因+多基因混合遗传模型联合分离分析了始雌花节位遗传规律。结果显示:L1×L2始雌花节位遗传符合2对加性-显性-上位性主基因+加性-显性多基因遗传模型,L2×L3的遗传符合1对加性主基因+加性-显性多基因遗传模型;L1×L2组合的B1、B2和F2群体遗传率(主基因+多基因)分别为66.13%、51.29%和68.27%,L2×L3组合的B1、B2和F2群体遗传率(主基因+多基因)分别为82.02%、64.87%和65.62%;L1×L2组合B1、B2和F2群体的环境方差占总表型方差的比例分别是23.43%、48.69%和31.73%,L2×L3组合B1、B2和F2群体的环境方差占总表型方差的比例分别是34.27%、55.40%和34.38%。结果表明:普通丝瓜始雌花节位是由主基因和多基因控制的数量性状,早熟性(较低的始雌花节位)不太可能通过杂种优势来实现;始雌花节位遗传不稳定,易受环境因素的影响,但定向选择会有较好的效果。

Major Cultivation Technology of HQ No.1, a New Flue-cured Tobacco Cultivar

The transplanting period, density, the number of left leaves and fertilizer amounts of HQ No.1 were explored in Hengyang. The results showed that with transplanting periods of March 5-March 15, and planting space of 120 cmx（50-60） cm, agronomic and economic characters of tobaccos showed insignificant differences. Specifically, plant height was growing upon the number of left leaf and fertilizer amount; tobacco yield and output value kept increasing upon fertilizer, and both reached maximums with pure N at 195 kg/hm^2, showing significant differences with the treatment of pure N at 135 kg/hm^2; the number of left leaf had the least effects on agronomic and economic characters of tobaccos. The research indicated that highly-qualified HQ No.1 can be produced, given that tobaccos are transplanted during March 10-March 15, planting density of 15 000-16 500 seedlings/hm^2, the number of left leaves of 22-24 leaves per seedling, and pure N of 150-165 kg/hm^2 in Hengyang.

Comparative Analysis of Morphologic Traits of 50 Large-flowered Chrysanthemum Varieties

With 50 large-flowered Chrysanthemum varieties from germplasm nursery of Wunaoshan Forest Farm in Macheng City as research objects, 64 morphological traits were investigated by field experiments adopting randomized block design. The morphological differences were observed by uniformity analysis, variability analysis, principal component analysis and cluster analysis. The result showed that the vari- able coefficients of 59 traits were greater than 15%; the contribution rate of first seven principal components reached 81.45%; and it was found by clustering analy- sis that the 50 germplasm resources could be divided into four clusters with obvious morphological differences, and plant type could be used as an index for classifica- tion.