马铃薯2n花粉植株后代与优良四倍体株系的遗传分析

本试验对5个TD后代和Serrana作母本与4个4x后代杂交得到的24个家系进行了评价,按设计Ⅱ方法对此群体的单株重、单株块茎数、商品率的配合力及遗传力进行了分析。HP.278.22×AVRDC单株重的特殊配合力最高为333.13,母本以Serrana,HP.278.22的一般配合力最高,分别为125.96,69.71,而父本以LT—7,AVRDC最高分别为62.88、10.88。单株重的遗传力为41.62％,而商品率、单株块茎数的遗传力均低,TD后代作亲本对特殊配合力影响较大表明2n花粉在传递杂合性方面的优势。6个最好家系中既有一般配合力作用大的,也有特殊配合力作用大的,或者两者兼而有之,并表明实生种子育种时,亲本的配合力测定是非常重要的。     

陆地棉F2代产量及形态性状的遗传分析

按3×5不完全双列杂交设计,对3个母本和5个父本的F2代进行遗传力及配合力分析,F2代衣分、子指、衣指、株高、单铃重遗传力高,而单铃子数、单株铃数、节数遗传力较低,爱字棉Sij各性状一般配合力较好,而吉尔吉斯×爱字棉Sij各性状表现较好的特殊配合力,是一个优势较强的组合.     

不同粒重小麦品种主要农艺性状的配合力和遗传力分析

为了解小麦粒重对产量影响的遗传规律,选6个千粒重高的品种SH4300、S5707、衡4568、D08-6、LS6109、华育116和6个千粒重低的品种H083-366、旱优0602-25、泰农8681、临抗6180、泰农2987、DH155两组亲本,按NCⅡ遗传交配设计,配制6×6不完全双列杂交获得36个杂交组合,对亲本及F₁的株高、穗长、分蘖、小穗数、穗粒数、单株产量、千粒重7个性状进行了配合力和遗传力分析。结果表明,D08-6千粒重的一般配合力最高,但其余各性状的一般配合力不高,导致其单株产量的配合力最低,做亲本时仅可提高千粒重;LS6109、华育116、S5707的单株产量配合力较高,但千粒重一般配合力都不是最高,主要是通过增加穗长、分蘖、小穗数、穗粒数增加产量。泰农8681、DH155各个性状的一般配合力均较高,其单株产量的一般配合力最高。故LS6109、华育116、S5707、泰农8681、DH155是较好的亲本材料。特殊配合力分析表明,单株产量特殊配合力最高的组合分别是LS6109/泰农2987、SH4300/泰农2987、D08-6/旱优0602-25;千粒重特殊配合力最高的组合分别是D08-6/临抗6180、LS6109/泰农2987、D08-6/H083-366,组合LS6109/泰农2987还具有较高的分蘖特殊配合力;SH4300/泰农2987千粒重的特殊配合力较高,D08-6/旱优0602-25分蘖和穗粒数的特殊配合力较高;组合LS6109/泰农2987、SH4300/泰农2987、D08-6/旱优0602-25在本试验中具有良好的产量表现,是较好的杂交组合。遗传力分析结果表明,株高、穗长、小穗数具有较高的广义遗传力和狭义遗传力（>65%）,可在早代进行选择;分蘖、穗粒重和千粒重广义遗传力较高,但其狭义遗传力较低（<50%）,适合在高代进行选择。     

黄淮南部和黄淮北部麦区小麦品种间的杂种优势、配合力及遗传特性分析

为了探讨黄淮南部和黄淮北部麦区小麦品种间的杂种优势以及主要农艺性状的遗传特性,以黄淮南部麦区的8个小麦品种和黄淮北部麦区的7个小麦品种为亲本配制56个不完全双列杂交组合,对亲本及杂交组合的9个农艺性状进行杂种优势、配合力及遗传特性分析。结果表明：（1）株高、千粒重和结实小穗数的平均中亲优势较高,单株粒数和穗粒数的平均中亲优势为负向优势,各性状均出现了中亲优势较高的组合,说明黄淮麦区不同生态区小麦品种间具有较强的杂种优势。（2）临Y8012、周麦27和邯生923单株粒重的一般配合力效应最高,其他农艺性状的一般配合力也基本上表现优秀,用作亲本可进一步提高组合的产量。单株粒重特殊配合力较高的组合为百农207×临Y8012、秋乐2122×邯生923、周麦27×济麦39、浚2016×冀麦181、周麦17×冀麦181。组合百农207×临Y8012、周麦27×邯生923和周麦27×济麦39两个亲本的一般配合力效应及特殊配合力效应均比较高,为本研究中的最优组合。（3）株高和千粒重的广义遗传力和狭义遗传力都较高,说明这两个性状加性效应较大且受环境影响较小,直接对这两个性状进行选择可取得良好的效果;单株粒重的广义遗传力较高,但其狭义遗传力较低,非加性方差成分占优势,因而对单株粒重直接选择效果不太显著,需要通过其他相关性状来辅助选择。     

马铃薯杂种群体的性状相关及其配合力分析

本试验以7个优良马铃薯品种(系)按不完全双列杂交设计配制组合,分析了群体主要性状与生产力的遗传相关及其配合力效应.结果表明,群体平均单株结薯数、平均块茎重、商品薯数量和产量及小薯数量和产量与群体产量的遗传相关达显著或极显著.平均块茎重、商品薯数量和产量是筛选商品价值较高的优良群体的重要相关性状.亲本的一般配合力效应在平均单株结薯数、平均决茎重、商品薯产量、小薯产量和数量几个性状上对模型Ⅰ差异显著,组合间的特殊配合力效应均达到显著差异.特殊配合力方差为总方差的61.47%～147.52%,表明该群体的生产力主要由非加性基因控制.相对配合力总效应值与产量的相关达极显著水平(r_(3.4)=0.99).综合评定亲本801-5,Katahdin和Baraka在马铃薯群体和品种选育中具有较高的利用价值.     

花生F4:5家系产量性状配合力分析

以8个花生品系配制的4 ×4不完全双列杂交组合的F4:5家系为材料,研究了单株果重、仁重、结果数、饱果数、百果重、百仁重和出仁率等7个产量性状的配合力.结果表明,这些产量性状都是以加性效应为主,多数性状还存在非加性效应;母本963-4-1的单株果重、单株仁重、单株果数、单株饱果数和出仁率的一般配合力(GCA)均最高,特殊配合力(SCA)方差则是904-79最高;父本中花8号单株果重和单株仁重最高,综合表现较好;组合904-79×中花8号的产量具有较高的SCA;大多数的优良F4:5家系来自上述3个亲本间的组合.亲本在F4:5家系表现出的GCA与早世代不一致,花生家系品种的选育应考虑亲本GCA在多个世代的综合表现.     

CIP家系在河北坝上的评价

在适宜的病毒侵染条件下 ,对将PLRV抗性引入高度抗PVX、PVY的CIP家系群体 ,经 1998～ 2 0 0 0年大田暴露试验 ,在我国首次进行了PLRV抗性分离、薯块形成评价和单株筛选鉴定 ;同时通过亲本在PLRV抗性、产量构成因素方面的方差分析和一般配合力测定 ,表明后代对PL RV的抗性主要来源于母本 ,产量构成因素则决定于双亲     

马铃薯主要块茎性状杂种优势及配合力分析

对马铃薯9个亲本及其不完全双列杂交组配的18个杂种无性一代的8个性状进行了杂种优势和配合力分析。结果表明:①8个性状均具有一定程度的杂种优势,超中亲优势的大小顺序为:烂薯率>块茎产量>结薯数>淀粉含量>单个块茎重>薯形>块茎外观>结薯习性;超高亲优势的排列顺序则为:结薯数>单个块茎重>块茎产量>块茎外观>烂薯率>淀粉含量>薯形>结薯习性。②品种P(2L0031-17)、P(4陇薯3号)、P(7L0218-38)、P(995D-P-8)具有较好的一般配合力,是理想的亲本材料。③组合P1×P4、P2×P9在淀粉含量、块茎产量等性状上具有较高的特殊配合力,产生较强的杂种优势。在马铃薯高淀粉育种中应选择高淀粉材料作为亲本之一,选配组合时亲本最好采用高×高类型或高×低类型配置组合。     

陆地棉16份材料配组的产量和纤维品质性状配合力分析

采用16个陆地棉品种(系)进行不完全双列杂交,按照8×8的NCII设计配制64个组合.分析F1产量性状和纤维品质性状的遗传力、一般配合力(GCA)和特殊配合力(SCA).结果 表明:配合力方差分析显示除整齐度指数无显著差异外,其他8个性状均达到显著或极显著水平.产量性状的广义遗传力除单株结铃数外均大于品质性状的广义遗传力,籽棉产量的广义遗传力最大,为75.01％,但狭义遗传力较低,衣分的广义遗传力和狭义遗传力值均较高,分别为72.92％和66.65％.产量性状一般配合力较高的亲本是A1、A3、B6和B8;品质性状一般配合力好的亲本为A3、A5和B2.产量性状特殊配合力较好的组合为A6B3、A1B1、A6B2和A3B7,分别比对照增产9.8％、7.6％、7.1％和5.6％.这些组合具有较大的利用潜力.     

对产生2n配子的二倍体杂种遗传效应的估计

用能产生２ｎ配子的二倍体杂种作父本，进行４ｘ—２ｘ杂交．采用不完全双列杂交设计，测定了两类亲本的杂种无性一代产量性状的变化动态．研究结果表明，单株产量的４Ｘ—２Ｘ一般配合力６９．６％，特殊配合力３０．３％．２ｘ父本遗传力３７．２％，４ｘ母本遗传力１６．３％，父母本交互遗传力２３．０％，４ｘ—２ｘ广义遗传力７６．７％，狭义遗传力５３．４％。含有Ｓ．Ｐｈｕｒｅｊａ血缘的２ｘ杂种，能较好地将高淀粉含量、早熟性、芽眼极浅等特性遗传给４ｘ—２ｘ杂种后代．经最新选择的２ｘ亲本，在缩短匍匐茎长度、减少结薯个数、提高大薯率和品质上有很大改进．     

Monitoring current season potato leafroll virus movement with an immunosorbent direct tissue blotting assay

A direct tissue blotting assay (DTBA) was used to track the movement of potato leafroll virus (PLRV) from newly infected foliage to the tubers. Plant and tuber characteristics were recorded to assess plant growth stage at inoculation and PLRV effect on yield. Russet Burbank potatoes were planted at different times in 1991 and 1992 to provide plants of different maturities which were then inoculated using PLRV carrying aphids. Aphids were allowed to feed two to three days after which an insecticide was applied. Stems and tubers were tested periodically for PLRV with DTBA after inoculation. Indexed tubers were grown out and ELISA tested in the greenhouse the following winter to confirm results of summer serological tests. Plant age affected percentages more consistently than did inoculation date. When plants approximately 43 days from planting were inoculated at different dates, early inoculation produced a higher percentage of infected plants. Conversely, when plants approximately 62 days from planting were inoculated at different dates, late inoculation resulted in a higher percentage of infected plants. However, early inoculation of young plants resulted in the highest infection percentages. Tuber size and yield were negatively affected by higher percentages of leafroll regardless of the stage of growth at inoculation. DTBA is best used for detecting PLRV in foliage of plants grown from infected tubers (i.e. secondary PLRV). DTBA is less accurate for detecting primary PLRV.     

凯普克对马铃薯的增产效果研究

为探索天然植物生长调节剂凯普克对马铃薯的增产效果,在同等施肥条件下进行两个马铃薯品种田间试验。结果表明:凯普克处理的马铃薯单株结薯数多,两个试验点比对照每株分别增加0.4和0.7个;凯普克处理大薯比例高,分别提高3个和4个百分点;产量增加,凯普克处理增产幅度分别为22.5%和19.2%。投入产出分析表明,所有试验点凯普克处理的产出都比对照高,每公顷增加收益分别为6 256和6 993元。凯普克在马铃薯种植中使用可行,可进一步扩大推广。     

Potato leafroll virus spread in differentially resistant potato cultivars under varying aphid densities

An action threshold of 3-10 green peach aphid,Myzus persicae (Sulzer), apterae per 100 lower leaves is recommended for use in Minnesota to prevent further spread of potato leafroll virus (PLRV) in potato,Solarium tuberosum L. This threshold was first developed and validated using the PLRV susceptible cultivar Russet Burbank. Here we report experiments to determine if higher aphid densities could be tolerated in PLRV resistant cultivars,i.e., Kennebec (moderately resistant) or Cascade (highly resistant), without an increase in PLRV infection. Insecticidal sprays were applied to plots when predetermined target aphid densities, based on number of apterae per 100 leaves, were reached: 3, 10, 30, and 100 (Russet Burbank); 10, 30, 100, and 300 (Kennebec); and 30, 100, 300, and 1000 (Cascade). The response variable was the average percentage of PLRV infected plants. Overall mean cumulative aphid-days and percent PLRV infection were 617 and 23.5% for Russet Burbank, 1,296 and 10.2% for Kennebec, and 4,816 and 9.5% for Cascade. For each cultivar, the highest target aphid density tolerated without an increase in PLRV spread was determined by comparing PLRV infection in plots sprayed on predetermined thresholds to PLRV infection in plots where aphids were rigorously controlled. This maximum density was 10 apterae per 100 leaves for Russet Burbank and 300 apterae per 100 leaves for Cascade. Results using Kennebec were ambiguous, but Kennebec was always more resistant to PLRV than Russet Burbank. Excised leaflet tests showed that the cultivars did not differ in resistance to green peach aphid. It appears that action thresholds based on green peach aphid apterae can be different depending upon the inherent PLRV-resistance of the cultivar.     

Interactions betweenPotato leafroll virus and potato plants and their implications for assessment of infection resistance

The effects of Potato leafroll virus (PLRV) isolates and inoculation method on the resistance to PLRV in potato clones and cultivars were investigated. In the season of inoculation, aphid inoculation resulted in higher proportions of infected plants and higher virus concentration in infected plants, as compared to graft inoculation. In these respects, grafting showed superiority over aphid inoculation in the tuber progeny of inoculated plants, though distinct dominance of aphid inoculation was observed for some tested clones. This leads to the conclusion that both methods should be applied as complementary tests for the efficient selection of highly resistant potato clones. For inoculations, two isolates of PLRV were applied, and one of them, isolate L7, was routinely used in screening breeding materials for resistance to the virus. The second isolate originated from plants of the highly resistant clone DW84-1457, which were incidentally infected with PLRV. The virus isolated from these plants was able to infect only specific clones, which were resistant to isolate L7. At the same time, potato clones with resistance derived from a source different from that present in DW84-1457, and standard susceptible and resistant cultivars, showed generally lower infection ratings after inoculation with the new isolate. This result suggests that the isolates may be different strains of PLRV. It is possible that under the strong selection pressure of resistance genes present in clone DW84-1457, a new isolate I-1457 could evolve the ability to overcome resistance to infection controlled by these genes.     

Impact of early-season water deficits on Russet Burbank plant development,tuber yield and quality

Russet Burbank potatoes grown on Owyhee silt loam were subjected to early-season moisture stress by delaying initiation of furrow irrigation up to seven weeks after planting. A range of water stress treatments from 4 to 7 weeks after planting resulted in reduced plant size, tuber number and total tuber weight per plant 8 1/2 weeks after planting. Early-season water stress resulting from delayed irrigation onset was associated with improved tuber quality at harvest. Plants water stressed before tuber initiation had fewer tubers with dark stem-end fry colors, reduced percentage of US No. 2 potatoes, and increased percentage and size of US No. 1 potatoes. Increasing duration of soil water potential below -60 kPa early in the season was associated with declining total yield in 1985 but not in 1986. To obtain optimum yield and processing quality, the first irrigation should be no sooner than full plant emergence.     

Effect of Nitrogen Rate on Growth,Yield, Economics and Crisps Quality of Indian Potato Processing Cultivars

A field study was conducted during 2000–2001 and 2001–2002 at the Central Potato Research Institute Campus, Modipuram, India, in order to increasing the processing-grade tuber yield of India’s first ever developed processing potato cultivars, Kufri Chipsona-1 and Kufri Chipsona-2. Tuber yield and post-harvest quality characteristics were evaluated in response to five N levels (0, 90, 180, 270 and 360 kg N ha^-1). The crop growth traits (stem number, plant height and compound leaf number) responded positively to N application, whereas the effect of N fertilization on processing-grade tuber number, total tuber number per ha and tuber number per plant was quadratic. There was a steady increase in tuber weight per plant, processing-grade tuber yield, total tuber yield and biomass yield in response to N application. Kufri Chipsona-1 produced a 23.6% higher tuber yield per plant than Kufri Chipsona-2. Agronomic N use efficiency decreased linearly with increased N doses. Specific gravity and tuber dry matter percentage responded positively to N application, while crisps colour (at harvest and after storage) and reducing sugars remained unaffected. Cultivar was the major factor that influenced the tuber quality parameters (specific gravity, crisps colour). Higher values of these quality traits were observed in Kufri Chipsona-2 as compared to Kufri Chipsona-1. Net income and benefit cost ratio (B:C) indicated that Chipsona cultivars should be fertilized with 270 kg N ha^-1 for realizing higher processing-grade yields and desirable quality tubers.     

Effect of time of inoculation with potato leafroll virus on development of net necrosis and stem-end browning in potato tubers

The Green Mountain cultivar was used in field tests to determine the effects of inoculating potato plants at various times with the potato leafroll virus (PLRV) on development of internal necrosis of tuber tissue. Viruliferous apterae of the green peach aphid,Myzus persicae (Sulz.), were placed on each stem in all hills to be inoculated in each 3.0 m single-row plot. Planting and inoculation dates were varied in all field experiments and, in one, several vine-killing dates were also included. All harvested tubers were stored for approximately four months at 10°C to enhance development of internal necrosis prior to examination. Similar but smaller greenhouse studies involving both apterous and alate green peach aphids were also conducted using Green Mountain, Irish Cobbler, and Russet Burbank cultivars. All results showed that as inoculation was delayed relative to plant development, more net necrosis (NN) occurred. Conversely, when plants were inoculated early, stem-end browning (SEB) rather than NN predominated. A high percentage of naturally occurring SEB tubers (cv. Russet Burbank) were found by ELISA to contain PLRV. Plants produced by these tubers only rarely developed leafroll symptoms. These findings suggest a previously unsuspected causal relationship between SEB and PLRV. Implications of this apparent relationship on the epidemiology of potato leafroll in Maine are discussed.     

马铃薯微型薯田间繁殖的研究

以马铃薯晚熟品种“下寨６５”为试验材料,研究了离体诱导微型薯直播田间繁殖块茎繁殖脱毒田间１～５代种薯的质量和效率。结果表明,生育阶段比同品种网室繁殖脱毒小薯同代脱毒种薯略迟;生长势、株高、茎粗、主茎分枝数、单株叶面积、根系数、匍匐茎数和匍匐茎长度等生长发育指标,ＰＶＸ、ＰＶＹ、ＰＬＲＶ和ＰＶＡ等重要病毒害发病率及病情指数,干腐病和软腐病发病率,晚疫病发病率和叶面枯死率相同;未发现环腐病和黑经病。单薯重量平均４５．１ｇ,随田间种植代数增加而增大;单株结薯数、单位面积结薯数逐代减小,脱毒田间１～４代单株产量和单位面积产量逐代增加,繁殖效率与脱毒小薯相同,故离体诱导微型薯田间繁殖块茎繁殖脱毒种薯是经济有效且切实可行的。     

Production of seed potatoes in Cyprus: incidence and economic importance of virus diseases

Summary Since 1981 seed potatoes have been produced on a semi-commercial scale in Cyprus by single multiplication of imported class A stocks. The main virus in these locally produced seed potatoes was potato leaf roll virus (PLRV) which was detected in 369 of 658 seed crops examined, at an average incidence of ca 1.5% (range 0.1%–15%). Tuber infections were detected in 203 of 223 samples tested, at an average incidence of ca 6.8% (range 1–32%), indicating a considerable spread of the virus during local seed multiplication. Potato viruses Y, X and A, and alfalfa mosaic virus occurred at much lower incidence than PLRV. The effect of secondary PLRV infection on ware-potato yield was determined in the cultivars Spunta and Cara, each planted on two different dates. In all four cultivar-planting date combinations there was a very close negative correlation between yield and virus incidence. At 100% infection, losses in total yield varied from 46% (later planting of Cara) to 72% (earlier planting of Spunta). The threshold level of infection for significant losses was ca 10%.     

Transfer of PLRV resistance fromSolanum verrucosum Schlechdt to potato (S. tuberosum L.) by protoplast electrofusion

Summary Somatic fusions between an accession of the diploid wild speciesSolanum verrucosum and a dihaploid S.tuberosum genotype were produced in order to incorporate resistance to potato leafroll virus (PLRV). In total 15 somatic hybrids out of 16 regenerants were obtained. Identification of hybrids was based on additive RAPD patterns, general morphological characteristics, chromosome numbers and chloroplast counts in stomata guard cells. A field trial was performed with the hybrids, their two parents and the control cultivar Kennebec to assess field performance and phenotypic variability. Yield parameters varied considerably among somatic hybrids. Some of the hybrids gave significantly higher yields, tuber numbers and tuber weights than both parents. Pollen fertility of hybrids ranged from 19 to 77%. Twelve hybrids were found to be resistant to PLRV.