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81.
Zhi-Shan Lin Zhi-Fu Cui Xiang-Yan Zeng You-Zhi Ma Zeng-Yan Zhang Toshiki Nakamura Goro Ishikawa Kazuhiro Nakamura Hisashi Yoshida Zhi-Yong Xin 《Euphytica》2007,158(1-2):109-118
Chromosome compositions of seven lines, derived from hybrids between a wheat cultivar and the wheat-Thinopyrum intermedium addition line Z6, with barley yellow dwarf virus (BYDV) resistance, were determined by genomic in situ hybridization, cytogenetic and SSR assays. The results showed that
line N522 was a disomic addition line, lines N420 and N439 were 2Ai-2(2B) chromosome substitution lines, lines N431 and N452
were 2Ai-2(2D) chromosome substitution lines, line N523 was a 2Ai-2S(2D) ditelosomic substitution line, and line N530 was
a double ditelosomic line with the mitotic chromosome number of 2n = 40 + 4t. One pair of telosomes in line N530 lacked several proximal SSR markers of chromosome 2AS, but possessed certain
terminal markers, which were consistent with an acrocentric structure, and the other pair of chromosome arms were presumably
2Ai-2S telosomes with BYDV-resistance. These wheat-Th. intermedium lines provide useful genetic resources for developing alien chromosome translocation lines. 相似文献
82.
83.
杂交稻抗二化螟的胞质遗传效应分析 总被引:1,自引:0,他引:1
以一套6种细胞质的同核异质广亲和不育系和两套同质(野败型和印水型)异核不育系与恢复系蜀恢162和密阳46配组的F1为材料,测定二化螟的幼虫存活率、幼虫体重和田间水稻枯心率,分析了不育系的细胞质、细胞核和质核互作对二化螟抗性的遗传效应。结果表明,二化螟幼虫在同核异质不育系的矮败型“国广2A”、D型“国广4A”、印水型“国广5A”和K型“国广6A”上的体重显著低于在野败型“国广1A”和冈型“国广3A”上的;在国广4A和国广5A上的枯心率(12.9%和14.1%)显著低于在其他同核异质不育系上的。水稻枯心率在野败型和印水型同质异核不育系的2种不育系之间均表现出显著差异。同核异质不育系和印水型同质异核不育系对二化螟存活率没有细胞质效应和质核互作效应。同核异质不育系的质核互作效应(47.1%)和细胞质效应(29.4%)是影响幼虫体重的主要因素;细胞核效应(76.0%)、细胞质(12.1%)和质核互作效应(10.4%)都影响着水稻枯心率。野败型同质异核不育系的细胞核效应(78.5%)是影响幼虫体重的主要因素,其次是细胞质效应(17.7%);枯心率受到细胞核效应(58.5%)和质核互作效应(35.7%)的影响。印水型同质异核不育系影响幼虫体重和枯心率的质核互作效应分别是26.5%和66.9%;影响幼虫体重的还有细胞核效应(50.7%)和细胞质效应(21.9%)。 相似文献
84.
采用普通小麦与天蓝偃麦草属间远缘杂种后代八倍体小偃麦(AABBDDEE)为母本,与羊草(滨麦草属)杂交,获得三属杂种后,再用普通小麦回交2 ̄3次,并对三属杂种以及回交世代中几个主要性状的遗传表现进行了研究,结果表明:①三属杂种F1的不育性,采用普通小麦通过回交可得到克服,并且随着回交次数的增加,结实率逐步提高;②回交后代有明显的超矮亲遗传现象;③天蓝偃麦草与羊草的抗病、大穗、多花多实等性状可直接传 相似文献
85.
Dilson A. Bisognin David S. Douches Kazimierz Jastrzebski William W. Kirk 《Euphytica》2002,125(1):129-138
The objectives of this study were to evaluate the use of potato (Solanum tuberosum L.) late blight (Phytophthora infestans (Mont.) de Bary) resistant parents in cultivar development and identify superior clones possessing moderate to high late
blight resistance combined with acceptable maturity and tuber quality. Ninety-five crosses were made between eight unadapted
parents with reported late blight resistance (B0718-3, Bertita, Bzura, Greta, Libertas, Stobrawa, Tollocan and Zarevo) and
susceptible parents (cultivars or advanced breeding clones) adapted to North American growing conditions. A total of 408 field
selected clones were assessed for late blight resistance in the greenhouse and in the field using a mixture of US8 P. infestans isolates (A2 mating type, metalaxyl resistant) that overcame all known R-genes except R8 and R9. Clones with ≤ 10% infected
foliar area in the greenhouse test or ≤ 0.30 RAUDPC (relative area under the disease progress curve) value in the field in
1998 were re-tested in 1999. A total of 118 (29% of 408) putative late blight resistant clones were selected. The eight late
blight resistant parents differed in both the ability to transmit late blight resistance and in the level of resistance transmitted
to the progeny. The Tollocan and B0718-3 families (half-sib progeny) had the greatest degree of resistance and frequency of
resistant clones. Scott-Knott cluster analysis ranked 79 clones (67% of 118) in the high and moderate late blight resistant
groups. Among these 79 clones, 19 clones had vine maturity equal to or earlier than mid-season combined with acceptable tuber
quality. Further selection in 2000 resulted in eight advanced selected clones (six from Tollocan and two from B0718-3 families)
with the same level of resistance as the parent combined with vine maturity and tuber quality equivalent to Atlantic, a standard
cultivar for chip processing in North America. The results indicate that this breeding approach can be used to select parents
for late blight resistance breeding and to identify superior clones with high levels of late blight resistance and marketable
vine maturity and tuber quality.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
86.
Nobuyoshi Watanabe 《Euphytica》1993,72(1-2):143-147
Summary The effect of specific plant characteristics on the grain and biomass yield of durum wheat can be accurately determined by using isogenic lines, which, however, were not usually available. This study reported the effects of long glume, glaucousness, glume pubescence, black glume and purple culm on the yield and its associated characteristics in near-isogenic lines of durum wheat cv. LD222, which were developed by continuous backcrossing. The long glume trait which resulted in a large photosynthetic area did not enhance yield. Increased glume size associated with the P gene tended to increase the main culm dominance, characterized such as vigorous main culm and weak tillers, and plant height, but to reduce tillering and spike number. Consequently, grain yield and harvest index declined. Under the adequate water supplying condition of the present study, the glaucous trait was beneficial for grain yield. The trait of glume pubescence did not excert any significant effect on the yield related characteristics in the LD222 background. The traits of black glume and purple culm reduced the number of spikes per unit area and the number of kernels per unit area. 相似文献
87.
Summary The near-isogenic lines of the wheat variety Triple Dirk supposed to differ only for Vrn genes have been investigated for their similarity to Triple Dirk and for purity. The NILs were found to differ from Triple Dirk. It was also discovered that Triple Dirk and the NILs each exist of more than one genotype. It is recommended that each NIL is tested for its Vrn-genotype and purified. New sets of Vrn NILs can only be made with these checked NILs and with one-plant progeny of the newly used recurrent parents. 相似文献
88.
89.
浙江省海宁市同仁养殖场沼气发电综合利用工程及效益分析 总被引:9,自引:0,他引:9
养殖业的污染已经成为制约规模化养殖业可持续发展的重要因素。浙江省海宁市同仁养殖园沼气发电综合利用工程,日处理养殖污水60余t,年处理量达2.37×104t,可每年节省开支1.9万元。日产沼气500 m3,用于发电,年可发电32万度,每年可创收12.8万元。太阳能集热装置100.8 m2,每年可节省开支1.26万元。年产有机肥480 t,每年仅有机肥一项的收入就可达到28.8万元。沼液经管道输送,作为附近10 hm2示范桑园及13.3 hm2稻田有机肥,又可为农民节约2.8万元。沼液、沼渣等的使用可提高土壤有机质含量,改良土壤,有利于土地资源的可持续利用。 相似文献
90.
应用GOMPERTZ模型预测了出行强度,并通过实际数据对GOMPERTZ模型参数进行了标定,采用实例对模型进行了比较分析。结果证明了GOMPERTZ模型用于小区居民出行强度预测的可行性,以及具有一定的优越性。再根据小区预测年的的人口便可以得到小区的交通生成量。 相似文献