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101.
Summary Three triticale lines, Siskiyou, M2A-Beagle, and OK 77842 have been reported to possess resistance to bacterial leaf streak caused by Xanthomonas campestris, pv. translucens (Xct.). The three resistant lines were crossed to susceptible lines and crossed with each other. F2, BC1-F1, BC2-F1 plants were inoculated with a mixture of two Xct strains. The segregation data indicate the presence of a single dominant gene in each of the three resistant lines to bacterial leaf streak. These three genes are either the same or closely linked herein designated as Xct1.  相似文献   
102.
G. S. Deol    G. E. Wilde  B. S. Gill 《Plant Breeding》1995,114(6):545-546
A total of 259 accessions of wild Triticum species originating from different countries, along with 91 triticale (6×)× bread wheat true-breeding derivatives, two bread wheat, and three triticale cultivars were screened for resistance to the Russian wheat aphid, a serious insect pest of the wheat crop. Twenty-four entries with low damage ratings on the basis of amount of leaf rolling and leaf chlorosis were retested along with resistant and susceptible controls. On the basis of leaf roll damage ratings, eight entries including four Triticum monococcum var. boeoticum (T. boeoticum), one T. monococcum var. monococcum (T. monococcum), two T. timopheevii var. araraticum (T. araraticum), and one triticale cultivar were significantly superior to ‘Karl’ (susceptible control) wheat. Among these, four accessions — three T. boeoticum and one T. araraticum— were significantly superior to all other entries and were equal to the resistant control (PI 372129) in resistance rating based on leaf rolling and leaf chlorosis (except T. boeoticum TA 202). The leaf chlorosis damage rating of all accessions were significantly lower than that of the susceptible check.  相似文献   
103.
Bronco 90 is an advanced line of hexaploid triticale and was reported to be a 2D(2R) chromosome substitution type. In F1 hybrids of this triticale with bread wheat, however, a meiotic configuration of 16 bivalents and 10 univalents was frequently observed indicating the presence of an additional D(R) chromosome substitution or D/R translocation. To determine the chromosome constitution of Bronco 90, C-banding and fluorescent in situ hybridization techniques were applied to somatic and meiotic metaphase chromosomes. These analyses revealed that in Bronco 90, the terminal 7% of the long arm of rye chromosome 5R is derived from the long arm of chromosome 4D. This translocated chromosome (5RS.5RL-4DL) and telosome 4DL formed metaphase I bonds at a frequency of 71%, demonstrating the significance of small terminal chromosome segments for pairing. This novel rye-wheat translocation is probably generated by homoeologous crossing-over because the distal region of 5RL is known to be homoeologous to that of 4DL. Possible association of this translocation with the absence of hairy peduncle character in Bronco 90 is discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
104.
Leena Maarit  Hömmö 《Plant Breeding》1994,112(4):285-293
Profound hardening is the prerequisite for survival of a cultivar over winter. In the present study, hardening abilities of 13 winter wheat, 10 rye, 3 triticale and 6 winter barley cultivars were determined in field samples collected during the autumns of 1990 and 1991 by measuring the amount of ion leakage from frost-treated leaf segments. The cultivars tested were selected from the Inter-Nordic Winterhardiness Project, in which Field Survival Indices were determined for a total of 23 winter wheat, 13 rye, 5 triticale and 11 winter barley cultivars in order to estimate winter survival potentials under Finnish conditions. The winter survival of the materials studied correlated well with their hardening ability assessed by using the electrolyte leakage method.  相似文献   
105.
Summary In the synthesis of primary hexaploid triticale, a cross-incompatibility barrier exists when tetraploid wheat (4X) is crossed with diploid (2X) rye. Fertilization may occur, however, abnormal endosperm development usually leads to premature embryo death. Four selected tetraploid wheat lines were crossed as females with seven open-pollinated rye lines and the resulting embryos were rescued in vitro 13–16 days after pollination. The wheat genotypes showed a major influence on crossability (seed set), embryo development and plant recovery. The highest efficiency of amphihaploid plant recovery (18.3 plants per 100 pollinated florets) was obtained from one 4X wheat line originally selected from the cross T. carthlicum × T. dicoccoides. Some of the 3X amphihaploid plants (ABR) derived from two wheat lines showed relatively high level of partial fertility presumably as a result of meiotic restitution. Correlation analysis showed that crossability (seed set), normal hybrid embryo development in vivo and embryo culturability were independent of each other.  相似文献   
106.
ABSTRACT

The aim of the study was to determine the long-term effect of legumes as forecrops on the productivity of rotation with nitrogen fertilisation. The rotation included: legumes + spring barley, winter triticale and winter rape. The study was conducted as a two-factorial field experiment with four replications. The present study showed that legumes, as forecrops, increased the yield of WT cultivated in the second year of rotation. The seed yield of WR cultivated in the third year of rotation significantly increased after all legume forecrops, with the exception of PEA. Yielding of these crops depended also on nitrogen fertilisation. In the case of WT doses 120 kg N ha?1 and 180 kg N ha?1 there was an increased yield compared with control independent of forecrop, but there were no significant differences between doses 120 and 180 kg N ha?1. The conclusion is that we do not need to use dose 180 kg N ha?1 for WT cultivated directly after legumes. In the cultivation of WR in the third year of rotation there is no need to use a dose of nitrogen 180 kg N ha?1 if the fore-fore-crops were indeterminate cultivars of BL or YL.  相似文献   
107.
ABSTRACT

In experiments with weed harrowing crops are negatively affected by competing weeds but also by the destructive effect of used implement. This research was carried out to find growth stages during which mixture of oat (Avena sativa L.) and triticaleTriticosecale Wittm.) was resistant to harrowing and was able to effectively recover from this physical disturbance. Plots were harrowed 1–3 times on the same day at six consecutive stages of mixture growth with spring-tine harrow. After the latest harrowing, all plots were sprayed with herbicide to exclude competitive effect of weeds on the mixture. Compared to non-harrowed plots plant density of mixture was significantly reduced after a single cultivation at 1- and 2-leaf stage (20% and 23% respectively), two cultivations at 3-leaf stage (22%) and three at the beginning of the tillering (21%). No yield penalty was noticed for the density reductions, thus showing high ability of mixture to recover from physical disturbance. We recommend plant emergence as an appropriate growth stage for single harrowing of oat-triticale mixture. Two cultivations on the same day should not be planned earlier than at the beginning of tillering.  相似文献   
108.
【目的】 研究冬性小黑麦种质资源表型性状的遗传多样性关系及筛选综合性状优异的冬性小黑麦种质,为冬性小黑麦育种、亲本选配及重要性状研究提供理论依据。【方法】 对113份冬性小黑麦8个表型性状采用Shannon-Wiener’s多样性指数进行遗传多样性分析,研究参试冬性小黑麦种质8个表型性状在连续2年的频次分布规律,分析各性状利用相关性及性状间关系,利用主成分分析构建冬性小黑麦种质综合评价体系,通过聚类分析明确参试材料的分类。【结果】 8个表型性状的平均变异系数为13.02%,单株籽粒产量、千粒重、每穗粒数、单株穗数、穗长、株高的变异系数超过10%,其中单株籽粒产量最大为18.01%,粒宽最小为5.09%;各性状遗传力均在85%以上;各性状遗传多样性指数为1.33~2.24,单株籽粒产量遗传多样性最高,粒长的遗传多样性最低;各性状存在着不同的相互关联,单株籽粒产量与每穗粒数、千粒重、穗长、粒长、株高呈极显著正相关,单株穗数与千粒重、每穗粒数呈极显著负相关。主成分分析提取到了3个主成分,累计贡献率为80.43%,第一主成分是籽粒产量主成分与单株籽粒产量、每穗粒数、千粒重有关,第二主成分是籽粒形态主成分与粒长和粒宽有关,第三主成分是株高主成分与株高和穗长有关;聚类分析将参试材料分为4类,第一类包含12份材料,属于高秆型材料,第二类包含40份材料,属于多穗型材料,第三类包含30份材料,属于高产型材料,第四类包含31材料,属于大粒型材料。【结论】 冬性小黑麦综合性评价筛选出表现优良籽粒高产型小黑麦11份。参试材料的遗传多样性丰富,综合评价较好,可有效补充小黑麦种质资源。  相似文献   
109.
为探究小黑麦(×Triticale Wittmack)干草对舍饲羔羊生产性能和采食行为的影响,本研究选用18只舍饲湖羊公羔,随机分为对照组、试验Ⅰ组和Ⅱ组,每组6只;对照组饲喂基础日粮,试验Ⅰ组和Ⅱ组在基础日粮中分别用10%、20%的小黑麦干草等量替代粗料。结果表明:Ⅰ组试验羊的平均日增重为189.72 g,显著高于对照组和Ⅱ组(P<0.05);试验羊采食量随小黑麦干草添加比例的增加而降低,Ⅱ组采食量显著低于Ⅰ组和对照组(P<0.05),采食时长极显著高于Ⅰ组和对照组(P<0.01);Ⅰ组试验羊排泄次数显著高于对照组(P<0.05),与Ⅱ组无显著差异(P>0.05);Ⅰ组试验羊反刍周期、反刍时间、反刍食团数和食团咀嚼总次数都极显著高于Ⅱ组(P<0.01)。综上可知,小黑麦干草作为粗饲料在羔羊日粮中适宜添加比例为10%,这为小黑麦干草饲料化开发利用提供了理论基础。  相似文献   
110.
This study aimed to determine whether powdery mildew caused by Blumeria graminis is an endemic pathogen of triticaleTriticosecale: Triticum × Secale), emerging as a result of recent changes in its pathogenicity, or whether it is a new pathogen, possibly resulting from hybridization between ff. spp. tritici and secalis. A secondary aim was to consider breeding practices that may have favoured this emergence. Phylogenetic analyses based upon six genes revealed the close relatedness of the novel entity and the ff. spp. tritici and secalis, but the IGS marker finally grouped together the isolates collected on triticale and on wheat, supporting the scenario of a recent host‐range expansion from wheat to triticale. Pathotype analyses concluded that virulence spectra of B. graminis infecting triticale were new in comparison to those observed for other reference formae speciales, and lack of fungicide resistance in triticale isolates strengthens the hypothesis of no or little genetic exchange between wheat and triticale populations of powdery mildew. This adaptation may follow the breakdown of plant resistance genes, which are probably not very diverse in current triticale cultivars since this criterion was not considered as a major one until recent years. Moreover, the complex selection and genetics of this hybrid cereal makes it difficult to predict the transmission of powdery mildew resistance genes.  相似文献   
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