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41.
42.
为筛选出适合于三江源区燕麦(Avena sativa)和小黑麦(×Triticale Wittmack)混播比例,在青海省甘德县进行了燕麦与小黑麦不同混播处理的研究。结果表明,在供试的5个混播处理中,混播组合燕麦60%+小黑麦40%处理下的干草产量最高,为13605 kg·hm–2,显著高于单播(P<0.05),和燕麦50%+小黑麦50%处理差异不显著(P>0.05)。燕麦60%+小黑麦40%处理下的燕麦株高最高,比燕麦单播提高6.5%。燕麦60%+小黑麦40%处理下的燕麦单株产量和单株地下生物量均显著高于燕麦单播和其他供试混播处理(P<0.05);小黑麦单株产量在燕麦40%+小黑麦60%处理下最高。燕麦60%+小黑麦40%处理下的燕麦和小黑麦的中性洗涤纤维和酸性洗涤纤维含量均低于单播,粗蛋白含量最高。利用干草产量、粗蛋白含量、可溶性糖含量、淀粉含量、酸性洗涤纤维含量和中性洗涤纤维含量的相对值进行隶属函数值综合评价,得出混播处理的最佳比例为燕麦60%+小黑麦40%。 相似文献
43.
小黑麦牧草产量与品质对施氮的响应 总被引:5,自引:0,他引:5
研究了施氮对不同刈割时期小黑麦中饲237 Triticale cereale cv. Zhongsi 237的饲草产量及营养成分的影响.结果表明:施氮和刈割时期对中饲237的草产量均有明显的影响,施氮可显著改善刈割后中饲237的再生性,促进植株生长,提高二茬鲜草、干草产量,且差异达极显著水平,同时可提高饲草的粗蛋白、粗脂肪、氨基酸含量,降低粗纤维含量,改善饲草品质.起身期刈割的处理,其二茬草的草产量、粗蛋白、粗脂肪产量均高于拔节期刈割的处理.追施氮肥处理的粗蛋白含量及产量均大于未追施氮肥的处理,而中性洗涤纤维、酸性洗涤纤维含量小于未追氮肥的处理. 相似文献
44.
The effect of interplant distance on the efficiency of mass selection was studied by performing five cycles of honeycomb selection
at two interplant distances (d), i.e. d = 100 cm (low plant density, implying absence of interplant competition) and d = 15
cm (high plant density, implying presence of intergenotypic competition). The offspring of plants selected either at low or
at high plant density were compared, both at high plant density and at low plant density, with the original population (in
fact: offspring of plants taken at random from this population). At high plant density offspring of plants selected at high
density performed better than the original population for most of the characters recorded on a per plant basis. At low plant
density offspring of plants selected either at high or at low density performed better than the original population for the
characters recorded on a per plant basis. The selections differed, however, significantly from each other: the offspring of
plants selected at low density performed better. As the latter did not occur at high density genotype × density interaction
was indicated. It is concluded that mass selection should be applied at the plant density used in commercial practice.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
45.
Genetic, agronomic and quality comparisons of two 1AL.1RS. wheat-rye chromosomal translocations 总被引:2,自引:0,他引:2
R. A. Graybosch J.-H. Lee C. J. Peterson D. R. Porter O. K. Chung 《Plant Breeding》1999,118(2):125-131
The 1AL.1RS wheat-rye chromosomal translocation originally found in ‘Amigo’ wheat possesses resistance genes for stem rust, powdery mildew and greenbug biotypes B and C, but also has a negative effect on wheat processing quality. Recently, a second 1AL.1RS translocation carrying Gb6, a gene conferring resistance to greenbug biotypes B, C, E, G and I, was identified in the wheat germplasm line ‘GRS1201′. Protein analytical methods, and the DNA polymerase chain reaction were used to identify markers capable of differentiating the 1RS chromosome arms derived from ‘Amigo’ and ‘GRS1201′. The secalin proteins encoded by genes on 1RS chromosome arms differed in ‘Amigo’ and ‘GRS1201′. A 70 kDa secalin was found in the ‘Amigo’1AL.1RS, but did not occur in the ‘GRS1201’1AL.1RS. Polymorphisms detected by PCR primers derived from a family of moderately repetitive rye DNA sequences also differentiated the two translocations. When ‘GRS1201’was mated with a non-1RS wheat, no recombinants between 1RS markers were observed. In crosses between 1RS and non-1RS parents, both DNA markers and secalins would be useful as selectable markers for 1RS-derived greenbug resistance. Recombination between 1RS markers did occur when 1RS from ‘Amigo’ and 1RS from ‘GRS1201’were combined, but in such intermatings, the molecular markers described herein could still be used to develop a population enriched in lines carrying Gb6. No differences in grain yield or grain and flour quality characteristics were observed when lines carrying 1RS from ‘Amigo’ were compared with lines with 1RS from ‘GRS1201′. Hence, differences in secalin composition did not result in differential quality effects. When compared with sister lines with 1AL.1AS derived from the wheat cultivar ‘Redland’, lines with ‘GRS1201’had equal grain yield, but produced flours with significantly shorter mix times, weaker doughs, and lower sodium dodecyl sulphate sedimentation volumes. 相似文献
46.
Fourteen accessions of rye when crossed to Triticum aestivum cv. C 306 (Ne1ne2ch1Ch2) yielded chlorotic F1 hybrids and six accessions involved in hybrid combination with the same tester produced normal F1 hybrid plants. Two rye accessions, namely, EC 179188 and EC 143825 when crossed to the wheat lines HD 2329 (ne1Ne2ch1Ch2) and NI 5439 (ne1ne2ch1Ch2) also produced chlorosis. The hybrids between T. macha and two rye accessions produced normal plants. Variable degrees of chlorosis were observed among different wheat × rye F1 hybrids. It is suggested that the rye accessions producing chlorosis in combination with wheat cvs. C 306, HD 2329 and NI 5439 (all Ch2-carriers) carry one of the complementary genes for chlorosis. Gene symbol Chr1 is proposed for the chlorosis gene of rye. 相似文献
47.
Whereas non-leguminous cover crops such as cereal rye (Secale cereale) or annual ryegrass (Lolium multiflorium) are capable of reducing nitrogen (N) leaching during wet seasons, leguminous cover crops such as hairy vetch (Vicia villosa) improve soil N fertility for succeeding crops. With mixtures of grasses and legumes as cover crop, the goal of reducing
N leaching while increasing soil N availability for crop production could be attainable. This study examined net N mineralization
of soil treated with hairy vetch residues mixed with either cereal rye or annual ryegrass and the effect of these mixtures
on growth and N uptake by cereal rye. Both cereal rye and annual ryegrass contained low total N, but high water-soluble carbon
and carbohydrate, compared with hairy vetch. Decreasing the proportion of hairy vetch in the mixed residues decreased net
N mineralization, rye plant growth and N uptake, but increased the crossover time (the time when the amount of net N mineralized
in the residue-amended soil equalled that of the non-amended control) required for net N mineralization to occur. When the
hairy vetch content was decreased to 40% or lower, net N immobilization in the first week of incubation increased markedly.
Residue N was significantly correlated with rye biomass (r=0.81, P<0.01) and N uptake (r=0.83, P<0.001), although the correlation was much higher between residue N and the potential initial N mineralization rate for rye
biomass (r=0.93, P<0.001) and N uptake (r=0.99, P<0.001). Judging from the effects of the mixed residues on rye N Concentration and N uptake, the proportion of rye or annual
ryegrass when mixed with residues of hairy vetch should not exceed 60% if the residues are to increase N availability. Further
study is needed to examine the influence of various mixtures of hairy vetch and rye or annual ryegrass on N leaching in soil.
Received: 10 March 1997 相似文献
48.
10个小黑麦品种(系)的遗传多样性分析 总被引:1,自引:0,他引:1
采用RAPD分子标记技术,对10个小黑麦品种(系)进行遗传多样性分析,结果表明,通过PCR扩增出384条带,其中79条谱带具有多态性,多态性比例为20.6%,平均扩增条带为20.3条,不同品种(系)间的遗传相似系数在0.250~0.833。聚类分析表明,以遗传相似系数0.580为阈值,可将10个小黑麦品种(系)分为3类。 相似文献
49.
内蒙古自治区乌兰察布市燕麦炭疽病病原鉴定 总被引:1,自引:0,他引:1
2010年8月,从内蒙古自治区乌兰察布市燕麦炭疽病病叶上分离得到产生镰刀形分生孢子的刺盘孢菌,依据柯赫氏法则、病菌形态特征和生物学特性,将其鉴定为Colletotrichum cereale Manns。病菌分生孢子盘生大量黑色针状刚毛;分生孢子单细胞,镰刀形,无色,(17.43~24.90)μm×(1.99~3.74)μm,平均(22.02±1.80)μm×(2.85±0.36)μm;分生孢子萌生的附着胞黑色,卵圆形或近圆形,(6.23~7.97)μm×(4.98~6.23)μm,平均(7.30±0.52)μm×(5.82±0.48)μm;菌丝生附着胞黑色,近圆形、长椭圆形或裂瓣状,(7.47~14.94)μm×(4.98~9.96)μm,平均(10.87±1.46)μm×(6.74±1.01)μm。病菌菌丝在5~35℃可生长,适宜生长温度为25℃;在人工接种条件下(离体叶片,23~25℃),菌株蒙-3-1对供试的2个裸燕麦品种和8个皮燕麦品种均具有强的致病性,但不侵染小麦、玉米、谷子和高粱。 相似文献
50.
The use of <Emphasis Type="Italic">Vp1</Emphasis> in real time RT-PCR to select for pre-harvest sprouting tolerance in triticale 总被引:1,自引:0,他引:1
In spite of the availability of laboratory and field tests there is still a major problem to select pre-harvest sprouting
(PHS) tolerant triticale varieties in a reliable, field-independent way. One approach to minimize the influence of environmental
conditions and physio-morphological traits on PHS detection is using molecular genetic tools. The ‘viviparous’ Vp1 gene has been repeatedly described to play an important role in dormancy in wheat. A quantitative RT-PCR assay based on the
expression of the Vp1 gene has been developed. Specific primers were designed for detecting Vp1 in both wheat and triticale. The expression levels of Vp1 were normalized using reference genes and relatively quantified with the comparative Ct-method. However, the first results indicate that the achieved Vp1 expression levels at 50 days post anthesis are not useful to select for PHS tolerance, both in wheat and triticale. This
negative outcome so far is possibly due to the existence of several splicing events or to the late assaying moment in the
kernel development, when Vp1 expression is found to be low. 相似文献