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161.
A 42‐day study was conducted where prawns (0.32 g) were fed diets where 0, 20, 50, 75 and 100 g (100 g)?1 of fish meal was replaced by soya bean meal (SBM). Feed intake was not significantly affected by inclusion of SBM, while specific growth rate and conversion efficiency decreased with increasing dietary SBM. Standard metabolic rate was significantly affected by dietary soya bean level, and was the highest in the 75 g (100 g)?1 SBM group. Carcass dry matter, crude fat and energy value declined with increasing SBM inclusion. SBM, without supplementation of amino acids or other additives, was not suitable as a major protein source in freshwater‐prawn diets.  相似文献   
162.
以苏蚕2号、海门大青皮、上虞田鸡青、美国蚕豆、陵西一寸、通鲜6号、日本大白皮、慈溪大白蚕以及自主研制新品系(长荚型蚕豆)共9个鲜食蚕豆品种为试材,进行低温保鲜比较试验。结果表明:以豆荚形式贮藏,以上虞田鸡青的保鲜效果最好,慈溪大白蚕、日本大白皮和长荚型蚕豆等3个品种次之,以2℃贮藏28d为宜。以豆粒形式贮藏,日本大白皮和慈溪大白蚕等2个品种保鲜效果最好,以2℃贮藏21d为宜。  相似文献   
163.
蚕豆蛋白亚基是蚕豆种子贮藏蛋白重要组成部分,深入鉴定蚕豆蛋白亚基,对了解蚕豆种子蛋白不同亚基的结构和功能具有重要意义。本研究应用液相色谱、电喷雾离子化与串联质谱联用技术和生物信息技术对蚕豆种子贮藏蛋白6个特异亚基进行了质谱鉴定。结果表明:这些特异亚基中的64、47、42及38ku分别鉴定出4个蛋白:豌豆球蛋白、豆球蛋白前体、假定糖结合蛋白、LEGB7_VICFA;97ku亚基蛋白为分子伴侣GroEL;96ku亚基蛋白由6个具有不同代谢功能的蛋白组成。  相似文献   
164.
蚯蚓蛋白水解酶对大豆蛋白的分解作用   总被引:2,自引:0,他引:2  
通过琼脂糖蛋白平板及水解度测定两种方法从定性、定量两个方面研究了蚯蚓蛋白水解酶对大豆蛋白的分解作用.同时测定并比较了蚯蚓豆粕反应物的氨基酸含量。结果表明.蚯蚓蛋白水解酶对大豆蛋白具有一定的酶解活性.其水解度达2.75%。利用蚯蚓处理豆粕,反应物中多种氨基酸含量均有不同程度增加,氨基酸总量与豆粕相比上升了27.83%,而且各种必需氨基酸的比例也更趋合理。因此,利用蚯蚓蛋白水解酶对大豆蛋白的分解作用可以有效地改善豆粕饲料的品质.  相似文献   
165.
南方小花蝽的发育与繁殖研究   总被引:1,自引:0,他引:1  
研究了在27℃条件下,南方小花蝽取食蚕豆蚜的发育和繁殖情况,并组建了实验种群生命表和繁殖特征生命表,计算了生命表的有关参数。结果表明,南方小花蝽取食蚕豆蚜时的未成熟期平均为21.02d,雌成虫平均寿命为7.55d,其平均产卵量为35.55粒,日产卵量为6.29粒,平均产卵期5.6d。南方小花蝽的种群趋势指数为7.17,净生殖率为6.57;内禀增长能力为0.074 9,周限增长率为1.077 4,种群加倍时间为9.257 6d。  相似文献   
166.
刘彩琴  漆文选 《蔬菜》2022,(1):46-49
由于连年重茬种植,青豆(菜用鲜食春蚕豆)病虫害逐年加重发生,严重影响了产品品质和产量。据调查,发生的主要病害有蚕豆轮纹病、赤斑病、褐斑病、锈病等,发生的主要虫害有地下害虫及蚕豆根瘤蟓、蚜虫等。采用选茬轮作、选用良种、种子消毒及绿色药剂防控等措施,可有效控制病虫害的危害。  相似文献   
167.
Among the main causes of poor yield in common beans are fungal, viral and bacterial diseases. Common bacterial blight, caused by Xanthomonas axonopodis pv. phaseoli (Xap), is one of the major bacterial diseases leading to significant losses in Brazil. Chemical control is ineffective, therefore, the use of resistant varieties becomes an interesting alternative. The objective of the present work was to evaluate disease resistance under natural infection of the pathogen in 109 recombinant inbred lines (F7) of P. vulgaris originated from the cross HAB-52 (susceptible — snapbean) × BAC-6 (resistant — common bean) in two different environments, as well as to calculate genetic parameters to assist in the selection of promising materials to be used in the CBB resistance breeding program. The data of the genetic parameters were compared to those calculated for the F3 generation originated from the same cross. The heritability results for DI (disease index) and VI (variation index) in F3 were 26.85% and 0.26, respectively, whereas in F7 they were 91.77% and 1.36, respectively. These results demonstrate a potential to be explored for this advanced population, that in the future, along with other pathogen variability studies and tests in other environments, may provide more information regarding a more precise evaluation of promising genotypes to be used in common bean breeding programs aiming to obtain CBB resistant varieties. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
168.
 透射电镜观察比较了蚕豆萎蔫病毒2号(BBWV-2)分离物PV131和P158侵染昆诺藜(Chenopodium quinoa)和蚕豆(Vicia faba)的细胞超微结构变化。结果显示:受PV131分离物侵染的昆诺藜叶肉细胞质中膜结构大量增生,形成有膜状结构、大小泡囊及电子致密物质的特殊膜增生区;病毒粒子散布在细胞质中,形成大块结晶体和管状结构,该管状结构直径约75nm,横切面由9个病毒粒子组成;受PV131侵染的蚕豆叶肉细胞中也形成膜增生区和管状结构,未见病毒结晶体。受P158分离物侵染的昆诺藜和蚕豆叶肉细胞病变情况与PV131分离物相似,形成膜增生区和相同的管状结构,在蚕豆叶肉细胞中也未观察到病毒结晶体。上述结果表明:2个BBWV-2分离物虽然在不同寄主植物上引起的细胞病变程度有差异,但其细胞病理学特征是由病毒基因结构所决定,与寄主的种类无关。  相似文献   
169.
Summary A landrace seed lot of runner bean (Phaseolus coccineus L.), obtained from the Budapest region, Hungary, was separated into five seed groups according to seed coat colour. 131 plants were grown randomly, and observed for 27 morphological and physiological characters. The collected data were analysed by ANOVA.Numerical taxonomy of the data employed Principal Components Analysis to generate scatter diagrams and Cluster Analysis to generate dendrograms, both before and after removing data on the four anthocyanin colour characters (seed coat, calyx, stem and flower colour) as these characters are probably controlled by a single major gene. The progenies from the five distinct parental seed groups showed much overlap in characteristics, indicating that they were not distinct lines but comprised a largely panmictic population.Some character associations were detected: plants from white seeds matured significantly later than those from black seeds, plants from white seeds with a few dark spots produced seeds significantly heavier than average, whereas those from white or black seeds produced significantly lighter seeds, although the average seed yield per plant did not differ significatly.  相似文献   
170.
Summary The adaptability and productivity of cool-season food legumes (chickpea, faba bean, lentil, pea) are limited by major abiotic stresses including drought, heat, frost, chilling, waterlogging, salinity and mineral toxicities. The severity of these stresses is unpredictable in field experiments, so field trials are increasingly supplemented with controlled-environment testing and physiological screening. For drought testing, irrigation is used in dry fields and rain-out shelters in damp ones. Carbon isotope discrimination (Δ13C) is a well-established screen for drought tolerance in C3 cereal crops which is now being validated for use in grain legumes, but it is relatively expensive per sample and more economical methods include stomatal conductance and canopy temperature. Chickpea lines ICC4958 and FLIP87-59C and faba bean line ILB938 have demonstrated good drought tolerance parameters in different experiments. For frost tolerance, an efficient controlled-environment procedure involves exposing hardened pot-grown plants to sub-zero temperatures. Faba beans Cote d’Or and BPL4628 as well as lentil ILL5865 have demonstrated good freezing tolerance in such tests. Chilling-tolerance tests are more commonly conducted in the field and lentil line ILL1878 as well as derivatives of interspecific crosses between chickpea and its wild relatives have repeatedly shown good results. The timing of chilling is particularly important as temperatures which are not lethal to the plant can greatly disrupt fertilization of flowers. Salinity response can be determined using hydroponic methods with a sand or gravel substrate and rapid, efficient scoring is based on leaf symptoms. Many lines of chickpea, faba bean and lentil have shown good salinity tolerance in a single article but none has become a benchmark. Waterlogging tolerance can be evaluated using paired hydroponic systems, one oxygenated and the other de-oxygenated. The development of lysigenous cavities or aerenchyma in roots, common in warm-season legumes, is reported in pea and lentil but is not well established in chickpea or faba bean. Many stresses are associated with oxidative damage leading to changes in chlorophyll fluorescence, membrane stability and peroxidase levels. An additional factor relevant to the legumes is the response of the symbiotic nitrogen-fixing bacteria to the stress.  相似文献   
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