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1.
In the past five decades, constant research has been directed towards yield improvement in pigeonpea resulting in the deployment of several commercially acceptable cultivars in India. Though, the genesis of hybrid technology, the biggest breakthrough, enigma of stagnant productivity still remains unsolved. To sort this productivity disparity, genomic research along with conventional breeding was successfully initiated at ICRISAT. It endowed ample genomic resource providing insight in the pigeonpea genome combating production constraints in a precise and speedy manner. The availability of the draft genome sequence with a large‐scale marker resource, oriented the research towards trait mapping for flowering time, determinacy, fertility restoration, yield attributing traits and photo‐insensitivity. Defined core and mini‐core collection, still eased the pigeonpea breeding being accessible for existing genetic diversity and developing stress resistance. Modern genomic tools like next‐generation sequencing, genome‐wide selection helping in the appraisal of selection efficiency is leading towards next‐generation breeding, an awaited milestone in pigeonpea genetic enhancement. This paper emphasizes the ongoing genetic improvement in pigeonpea with an amalgam of conventional breeding as well as genomic research.  相似文献   
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将土、基础及上部结构物视为一个整体,在计入土的弹性抗力后对多跨无铰拱和连续刚构的上下部结构进行联合计算,并给出了算例,可供设计参考。  相似文献   
4.
The x-ray structure of chicken skeletal muscle troponin C (TnC), the Ca2+-binding subunit of the troponin complex, shows that the protein is about 70 angstroms long with an unusual dumbbell shape. The carboxyl and amino domains are separated by a single long alpha helix of about nine turns. Only the two high-affinity Ca2+-Mg2+ sites of the COOH-domain are occupied by metal ions resulting in conformational differences between the COOH- and NH2-domains. These differences are probably important in the triggering of muscle contraction by TnC. Also the structure of TnC is relevant in understanding the function of other calcium-regulated proteins, in particular that of calmodulin because of its strong similarity in amino acid sequence.  相似文献   
5.
Abstract.— Quantitative changes in the protein, lipid and carbohydrate were studied in the early larval stages of developing freshwater prawn Macrobrachium rosenbergii reared under fed and starved conditions to understand the relative importance of these nutrients in energy metabolism of the growing larvae. Larvae obtained from several females were stocked into three 250-L tanks at a density of 30 larvae/L. The feeding regime consisted of newly hatched Artemia nauplii. Protein was always the major organic constituent followed by lipids and then carbohydrates of both fed and starved larvae. Protein levels of both fed and starved larvae increased during development, suggesting an important role in morphogenesis. The decline of lipid during the larval growth that was more rapid for starved larvae, suggests a probable utilization of lipid as the major metabolic source of energy. Carbohydrates formed less than 5 and 2.4% of the larval dry weight of fed and starved larvae, respectively, suggesting their limited role in larval metabolism.  相似文献   
6.
1. Wheat, triticale 131 or triticale 72‐S could replace up to half the maize in broiler diets without affecting performance. Replacing more of the maize on either an equal nitrogen basis or a weight basis adversely affected performance.

2. Triticale 72‐S appeared to be superior to triticale 131 as a direct replacement for maize, but both grains were inferior to maize as energy sources.  相似文献   

7.
1. Dry rabbit excreta were found to contain 188.1 g crude protein, 6.6 g non‐protein nitrogen, 0.3 g ammonia, 89.8 g moisture, 8.0 g ether extractives, 135.2 g crude fibre, 266.9 g ash and 19.18 MJ gross energy/kg. Methionine and lysine contents were 3.95 and 4.29 g/100 g protein, respectively.

2. In one experiment, 0, 50, 100 or 200 g rabbit excreta/kg were substituted for maize in a broiler diet. Chickens receiving the diet containing 200 g rabbit excreta/kg gained significantly less weight to 8 weeks of age than those receiving other diets.

3. In a second experiment, 0, 100, 150 or 200 g rabbit excreta/kg were substituted primarily for maize in a broiler diet to provide equal energy and protein contents. Weight gains to 8 weeks of birds receiving these diets did not differ significantly. The uncorrected metabolisable energy content of the excreta was 9.15 MJ/kg.

4. There were no gross pathological changes in the birds fed on the experimental diets.  相似文献   

8.
1. The nitrogen‐corrected metabolisable energy contents of the triticale varieties Multi Graze, Graze Grain 70, 204 and 131 were 12.28, 12.69, 12.37 and 12.03 MJ/kg respectively.

2. Increasing proportions (0, 25, 50 or 75%) of the maize of a diet were replaced by triticale 131 to provide diets of equal energy and nitrogen contents for broilers. These diets resulted in weight gains of 1.775, 1.782, 1.713 and 1.808 kg respectively at 8 weeks and there were no significant differences among efficiencies of food conversions.

3. Dressed carcass weights as percentages of body weight were 74.38, 75.01, 73.98 and 74.50 respectively and did not differ significantly.

4. Triticale in the diet did not seem to influence the relative weights of either liver or gizzard.

5. The flavour of the meat seemed to become less acceptable as the triticale in the diet increased but there were no significant differences in tenderness and juiciness of the meat caused by the treatments.  相似文献   

9.
番茄果实采后一氧化氮处理对活性氧代谢的影响   总被引:13,自引:1,他引:13  
 以番茄品种‘百利’为试材, 研究了NO处理对其采后活性氧代谢的影响。结果表明: NO处理可推迟果实呼吸和乙烯高峰的出现, 抑制O·2 和H2O2 的累积, 保持了贮藏后期SOD、CAT、POD、APX 较高的活性以及GSH和AsA含量的较高水平, 延缓了MDA含量和膜相对透性的升高, 降低膜脂过氧化程度, 延缓了果实衰老。  相似文献   
10.
不同倍性西瓜的叶表皮微形态特征比较   总被引:12,自引:0,他引:12  
扫描电镜观察结果表明,随着西瓜倍性的增加,叶片保卫细胞和表皮细胞增大,叶片单位面积上的气孔和表皮细胞的数目减少,细胞的大小与西瓜倍性呈正相关,单位面积上的细胞数目与西瓜倍性呈负相关。通过FDA荧光记数法观察,4x、3x和2x的叶片保卫细胞中的叶绿体数目分别为19.9±3.4,15.9±2.2,11.5±1.5,其比例约为4∶3∶2,与西瓜的倍性一致。根据此方法可以快速有效地对西瓜倍性进行早期鉴定。  相似文献   
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