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11.
Nineteen tetraploid wheats (Triticum turgidum), differing in their agronomical behaviour and geographic origins were grown in two experiments and analysed for the following physiological traits: soluble leaf protein content, rubisco content, initial and potential carboxylase activities of this enzyme as well as its relative content in percentage of protein, the specific activity of the enzyme and its activation state. The results show a high genetic variability for all studied traits and more particularly for the initial carboxylase activity. High phenotypic correlation was observed between the rubisco content and its potential activities, in the first experiment. Correlation between souble leaf protein and rubisco content was significant in 9 genotypes of the second experiment. 相似文献
12.
Summary A combination of compatible second pollinations and embryo rescue was applied for systematic production of true tetraploid hybrids from crosses between disomic tetraploid Solanum acaule and tetrasomic tetraploid potato, S. tuberosum. Several genotypes of tetraploid potatoes were pollinated with S. acaule, and the compatible second pollinations were made on the following day, with a genotype of S. phureja, IvP 35 to promote fruit development. Embryo rescue was carried out in 21 families, 14 to 27 days after the first pollination. A total of eight plants were obtained from the embryo rescue and their chromosome numbers were counted in the root tips. Three of the eight plants were identified as tetraploid, and five others as diploid. Morphology, isozyme banding patterns, and pollen stainability, as well as potato spindle tuber viroid (PSTVd) resistance, indicated the hybrid nature of the three plants. This is the first report of successful tetraploid hybrid production between disomic tetraploid S. acaule (4x) and tetrasomic tetraploid potatoes. Seed set from the crosses between one of hybrids and diploid potatoes indicated workable levels of both male and female fertility for introgression of valuable genes from S. acaule into the cultivated potato gene pool. The methodology used may be applied to other disomic tetraploid tuber-bearing Solanum species and with some modifications also to distantly related solanaceous species and genera. 相似文献
13.
Helena Poyarkova 《Euphytica》1988,38(1):11-23
Summary Research on the morphology, geography and infraspecific taxonomics of Triticum dicoccoides Körn. performed during the 80 years since its rediscovery by Aaronsohn is reviewed. T. dicoccoides is a vluable genetic resource for the improvement of cultivated wheat. Its intraspecific structure is, however, not known sufficiently. It is evident that T. dicoccoides is subdivided into two morphologically and geographically distinct forms. The intepretations of these forms by various authors are diverse. There is also no consensus concerning their geographical within the general range of T. dicoccoides. It is necessary to carry out a detailed morphological study in order to define their taxonomical rank and specify their ranges. It would be expedient to perform comparative genetic, biochemical and agronomic investigations of the two T. dicoccoides infraspecific types. 相似文献
14.
J. B. O. Owuor 《Euphytica》1985,34(2):355-360
Summary Melosis was studied in Coffea arabica, in induced tetraploid C. canephora, in their F1 hybrid (arabusta hybrid) and in backcross generations of the hybrid with C. arabica as recurrent parent. Irregularities were observed, consisting of univalents (especially in the arabusta hybrid), multivalents (especially in tetraploid C. canephora) and uneven distribution of chromosomes at first anaphase. Chromosome distribution was improved by backcrossing. Meiotic irregularities wer negatively correlated with pollen fertility. 相似文献
15.
Summary A genetic study of a range of NORIN 10 based semi-dwarf durum wheats showed that only Gai/Rht 1, located on chromosome 4A, was present. No varieties carrying a second Gai/Rht allele were identified and deliberate attempts to introduce Gai/Rht2 into tetraploid wheats have so far been unsuccessful.In a spaced plant trial of homozygous random F3 lines from two tall x semi-dwarf crosses, the semi-dwarfs has lower ear yields, due mainly to reduced kernel weight, but had higher tiller numbers than the tall genotypes. Although there was no difference in overall plant yield between talls and semi-dwarfs, an analysis of character associations within the semi-dwarf F3's showed positive height-yield and height-kernel weight correlations indicating that selection for tall dwarfs may be a useful breeding strategy in tetraploid wheats. 相似文献
16.
四倍体刺槐生态饲料林栽培试验 总被引:1,自引:0,他引:1
四倍体刺槐是近几年培育成功的刺槐新品种,它不但保持了普通刺槐的原有属性,同时又具有很多新的特性.通过对四倍体刺槐生态饲料林栽培技术的试验研究,结果表明,不同定植密度对苗木成活率无显著影响,但对采割量影响显著.以每667 m2定植3 300株枝条采割量最大;四倍体刺槐2号和5号与普通刺槐相比,粗纤维和粗蛋白含量高,灰分含... 相似文献
17.
四倍体苇状羊茅和多花黑麦草F_1杂种的幼胚培养及再生植株的形态特征 总被引:3,自引:0,他引:3
研究了在直接成苗培养基上不萌动的四倍体苇状羊茅和多花黑麦草杂种幼胚通过诱导愈伤组织获得再生杂种苗的方法。结果表明,杂种愈伤组织随着继代培养时间的延长,分化成苗能力逐步下降,在不改变培养基的情况下,分化能力可保持8个月;改变脱分化培养基中NH4NO3或KNO3的浓度可显著提高愈伤组织的分化能力。此外,还讨论了再生植株的形态变异 相似文献
18.
19.
四川四倍体小麦地方品种酯酶同工酶 总被引:9,自引:1,他引:9
对30份产于四川的四倍体小麦地方品种(T.TurgidumL.)的酯酶同工酶分析表明,四倍体小麦的幼苗、剑叶和幼穗间酯酶同工酶存在较大差异。其中,幼苗有14条带,12种类型;剑叶15条带,13种类型;幼穗13条带,11种类型。3次测定合并分析,则产生21种类型。若仅以1次测定看,多样性指数以剑叶最高,为0 1119,说明剑叶酯酶同工酶能更好地反映其遗传多样性。同时酯酶同工酶的差异证明,来源相同又同名但原始编号不同的两份"棒棒南麦"和两份"早佐"具有不同的基因型,应视为不同的品种。 相似文献
20.
Getachew Belay T. Tesemma E. Bechere D. Mitiku 《Genetic Resources and Crop Evolution》1995,42(4):387-391
Summary Purple-grain tetraploid wheats (Triticum turgidum L.) are widely cultivated in the Ethiopian highlands despite the claim that they have lower industrial quality properties
and market prices than the white or red/brown seed-colour types. In an attempt to find a possible explanation for this, the
three seed-colour groups were compared for grain yield, other 11 agronomic traits and protein content. Five traits displayed
significant differences between seed colour groups where the purple-seed was superior; earlier maturity, shorter height, and
higher fertility, tillering capacity and harvest index. Most of these are important adaptive traits to waterlogging stress
on dark-clay soils (pellic vertisols) where the great bulk of the Ethiopian tetraploid wheats have been grown. Furthermore,
among the three seed-colour groups, purple-seed wheat has the best malting quality for the preparation of arekie, a locally
distilled spirituous liquor. It, therefore, appears that both natural and human selections have been reponsible for their
continued cultivation. Hence, the notion that purple-seeded wheat is the “least preferred” should be interpreted carefully
not to necessarily address the whole community in Ethiopia. As to their taxonomy, all tetraploid wheat taxa (T. turgidum L. sensu lato, 2n = 4x = 28) that are found in Ethiopia, with the possible exception of T. dicoccon Shrank (locally known
as Adja), may possess the purple pericarp-colour, although in varying frequencies; very low inT. polonicum L., and high inT. carthlicum Nevski andT. durum Desf. 相似文献