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1.
Grain yield and yield components (grains per ear, grain weight, 1000-grain weight, ear weight, ear seed ratio and dry matter partitioning between ear and seed) were examined in a wheat genotype (PBW-343) with well-filled grains and a Triticale genotype (DT-46) with poorly filled grains (showing grain shrivelling) grown in pots. Six days after anthesis (DAA), benzyladenine (BA) @2 µg ear−1 and abscisic acid (ABA) @4 µg ear−1 were injected at the base of the mother shoot ear in both species. It was observed that, in both wheat and Triticale , BA increased the grain weight, grain number and partitioning of dry matter between ear and seed, whereas ABA decreased the grain weight, grain number and dry matter partitioning between ear and seed. However, these decreases were slower in Triticale than in wheat. BA treatment increased the grain dry matter accumulation, which in turn resulted in better filling of grains and increased the grain weight in both wheat and Triticale . The average grain weight of Triticale was lower than that of wheat. Thus, it appears that variation in grain weight between wheat and Triticale might be due to different availabilities of growth-promoting phytohormones such as cytokinins and assimilates.  相似文献   
2.
苏南丘陵区秋播苜蓿适用伴生作物筛选试验   总被引:3,自引:0,他引:3  
为解决苏南丘陵区苜蓿苗期的杂草问题,从保护播种入手,在多年生黑麦草、一年生黑麦草、黑麦、小黑麦四种作物共五个品种中寻找适宜的伴生作物.通过对产量、株高、杂草率等多个指标测定分析,筛选出中新830小黑麦、赣选一号黑麦草适于用作苜蓿播种的伴生作物,同时获得两个苜蓿存活率最高的处理:苜蓿(15kg/hm^2)+中新830小黑麦(150kg/hm^2)撒播及苜蓿(18 kg/hm^2)+中新830小黑麦(250kg/hm^2)30cm条播.试验还表明撒播方式下,苜蓿播量与其竞争力不成正比。  相似文献   
3.
为了解小黑麦耐盐性与离子吸收之间的关系,以4个耐盐性不同的小黑麦品种为材料,分析了不同浓度NaCl(0、50、100、200mmol·L-1)胁迫处理10d后,小黑麦幼苗鲜重、地上部分和根部Na+、K+、Cl-分布以及限钠能力和K+/Na+的变化。结果表明,随NaCl浓度的升高,4个小黑麦品种鲜重均逐步降低,Na+、Cl-含量大幅提高;除中饲828外,其他3个品种的地上部Na+、Cl-含量均高于根部;K+含量随NaCl浓度的升高而逐步下降,根部下降幅度大于地上部。随NaCl浓度的升高,小黑麦地上部限钠能力及地上部分和根部K+/Na+逐渐降低。在4个品种中,抗盐性强的中饲828地上部能维持相对较低的Na+、Cl-含量,具有较高的K+/Na+,生物量也较高;盐敏感品种劲松49则相反。说明限制地上部Na+的吸收和维持较高的K+/Na+是小黑麦耐盐的策略之一。  相似文献   
4.
Summary Fifteen lines of triticale were studied using the C-banding staining method. A typical, complete chromosomal complement was found in 11 lines, while the remaining lines demonstrated some variations. A slight modification in the technique is discussed.Supported in part by CSRS/USDA Grant No. 801-15-03A.  相似文献   
5.
Summary Callus was obtained from immature excised embryos of triticale using MS medium supplemented with 3 mg/l 2,4-D and 1 mg/l kinetin. The presence of 2,4-D was essential for continued callus proliferation. Plantlets were induced from the calli by sub-culturing on medium either devoid of auxin or containing 0.1 mg/l 2,4-D. The capacity to produce callus and to form organs and plantlets differed markedly among the genotypes used. Lines also had distinct response to presence and absence of 2,4-D in the regeneration media. The callus of most triticale lines used differentiated into organs more readily on MS medium supplemented with 0.1 mg/l 2,4-D than on medium without growth regulators. Very high frequencies (up to 75%) of plantlet regeneration were observed in several of the triticale lines studied.  相似文献   
6.
In cereals, chromosome doubling of microspore-derived haploid plants is a critical step in producing doubled haploid plants. This investigation was undertaken to study the effect of incorporation of colchicine in the induction medium for anther culture, and the effect of colchicine on anther culture-derived plants of triticale grown under controlled greenhouse conditions. In the latter case, chromosome doubling of adult sterile plants derived from anther culture of fourteen triticale populations was attempted, where androgenetic plants with non-dehiscent anthers were cloned and subjected to the colchicine treatment, and then grown with the aid of hydroponics. The hydroponic system provided optimal conditions for recovery of the affected haploids from the toxic effects of colchicine treatment and all colchicine-treated plants survived. A topcross-F1 (TC1F1) population with timopheevii cytoplasm produced the highest percentage of plants with seed-set either due to chromosome doubling by colchicine (98%) or spontaneous doubling of chromosome number (15%). Colchicine-treated anthers performed inferior than control in both induction and regeneration phases. One of the key observation of this study was the reversal from reproductive stage back to the vegetative stage which in turn enabled further cloning of haploid plants under hydroponic conditions once they were identified as sterile. The one hundred percent survival rate of in vitro-derived plants, 100% survival rate of colchicine treated haploid plants and the high chromosome doubling success rate (X = 82.3) observed in this study imply that a temperature-controlled greenhouse with an hydroponic system provides an efficient environment for inducing chromosome doubling of haploid plants in cereals. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
7.
通过对从国际玉米小麦改良中心(C IMMYT)新引进的183份小黑麦材料的主要农艺性状及细胞学特点鉴定,发现绝大部分材料对当地的气候环境条件有很强的适应性,生长发育良好,对白粉病免疫;且都是细胞学稳定的六倍体(2n=42)小黑麦;并从中筛选出了一些具有代表性的好材料。  相似文献   
8.
利用Griffing完全双列杂交方法Ⅱ,对新疆自育小黑麦6个亲本的单株产量、株高、穗下节间长、每穗粒数、穗长和千粒重6个产量性状的配合力进行了研究,结果表明,新小黑麦3号、新小黑麦4号的单株产量、千粒重、株高和穗下节间长4个性状的一般配合力效应值显著高于其它亲本,是相对较好的育种亲本;SD04-1 × HO3-7,XIN Triticale No.1×XIN Triticale No.3,XIN Triticale No.1×XIN Triticale No.4和04CAOJIAN3×XIN Triticale No.3组合的特殊配合力效应值在所有性状上均表现为正向效应,可以成为提高产量相对较好的组合.  相似文献   
9.
小麦、黑麦及小黑麦的耐盐性研究   总被引:15,自引:1,他引:15  
对小麦,黑麦及小黑麦在盐胁迫营养液培养后的芽长,根长,植株鲜重,干重及叶片细胞膜透性分析结果表明,NaCl胁迫下其生长速度及生长量均受到抑制,但不同材料及植株不同部位所受影响不尽相同,八倍体和六倍体小黑麦受抑制生活方式明显小于硬粒小麦和普通小麦,其叶片细胞在盐胁迫下的伤害率亦明显小于后者,盐对小麦,黑麦和小黑麦根部的影响大于对地上部的影响。  相似文献   
10.
综述小黑麦产量和品质方面潜在的生理学和酶学机理,同时探讨不同农艺措施对小黑麦产量和品质的影响,为进一步挖掘小黑麦的潜能提供借鉴。  相似文献   
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