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1.
KC Silva‐Santos CR Ferreira GMG Santos MN Eberlin LS Siloto CO Rosa TN Marcantonio MM Seneda 《Reproduction in domestic animals》2014,49(5):711-718
The aim of the present study was to compare the lipid profile in oocytes of indicus and 1/2 indicus × taurus cows with high and low antral follicle count (AFC)/oocyte yields. After an OPU procedure (D0), antral follicles ≥3 mm were counted by ultrasonography (D4, 19, 34, 49, 64), and cows were assigned to groups with either high AFC (≥30 follicles; indicus, NH group; 1/2 indicus × taurus, AH group) or low AFC (≤15 antral follicles; indicus, NL group; 1/2 indicus × taurus, AL group). The lipid profiles of the oocytes were determined by MALDI‐MS. For GI, GII and GIII oocytes, the indicus samples tend to cluster separately from the 1/2 indicus × taurus samples. The lipid species [PC (P‐38:5) + H]+ and/or [PC (P‐36:2) + Na]+, [PC (38:2) + H]+, [PC (38:5) + Na]+ and [TAG (60:8) + NH4]+ were more abundant in indicus (NH and NL groups) than 1/2 indicus × taurus. The higher lipid content in the indicus oocytes likely reflects differences in the rate of lipid metabolism and may contribute to oocyte competence and embryo development. 相似文献
2.
Summary Ten cultivars of oats (Avena sativa L.) were investigated for their isozymes of esterase (E), leucine aminopeptidase (LAP), and anodal and cathodal peroxidase (APX and CPX).From repeated observations, a typical zymogram was prepared for each enzyme system, and the frequencies of the isozyme bands were scored for each variety separately. The results showed that: (1) most of the isozyme bands are very stable in their appearance on the gel: (2) each variety has a characteristic isozyme pattern; (3) 7 out of 10 oat cultivars showed no intravarietal isozyme variation. Some variation was found for the varieties Mesa, Rapida and Curt. This overall high level of homozygosity and homogeneity of these varieties for the isozyme bands makes this technique useful for varietal identification. 相似文献
3.
Among the wheatgrasses that are possible sources of genetic resistance for wheat to barley yellow-dwarf-virus disease (BYD) are those that have been commonly subsumed under the name Agropyron elongatum (Host) P. Beauv. Two of these wheatgrass species are the diploid Lophopymm elongatum (Host) Á. Löve (2n = 2x = 14) and the decaploid L. ponticum (Podp.) Á. Löve (2n = 10x = 70). These two species, the addition and substitution lines of L. elongatum chromosomes in hexaploid wheat (Triticum aestivum L.), and derivatives of hybrids between hexaploid wheat and L. ponticum, were screened for resistance to BYD, as defined by visual symptoms in field-grown plants. The two species, an amphiploid derived from L. elongatumבChinese Spring’ wheat, and the derivatives involving L. ponticum chromosomes were all highly resistant. The substitution and addition lines of L. elongatum chromosomes in ‘Chinese Spring’ revealed that the genetic control of resistance in L. elongatum must be complex, with more than one critical locus involved. Chromosomes 2E and 5E are involved and there are lesser contributions to resistance from the remaining wheatgrass chromosomes. One highly resistant derivative was determined to have only three pairs of L. ponticum chromosomes. It has a wheat-like morphology and shows promise for further characterization. 相似文献
4.
Summary The gametocidal effects of RH-531, RH-532, and RH-2956 were studied with three rates and times of foliar application on two spring wheat (Triticum aestivum L.) varieties, Anza and Yecora 70. RH-531 and RH-532 applied at or before booting stage caused rather large reduction in plant height while RH-2956 had a small effect on height. Application of any of the three chemicals on Anza at meiotic stages reduced self-pollination (SP) fertility by 97–99%. If 90% SP fertility reduction is acceptable, the application time could vary from premeiosis to postmeiosis for Anza. Yecora 70 was less sensitive than Anza to gametocide treatments. The lowest SP fertility obtained in Yecora 70 with RH-531, RH-532, and RH-2956 was by treatment at booting (4 kg/ha), at premeiosis (2 kg/ha), and heading (8 kg/ha), and the corresponding SP fertility reductions were 74, 89, and 71%. Pollen stainability-determined by aceto-carmine, IKI, and Alexander's stains-was not affected by gametocide treatment and was not useful in evaluating sterility induced by these chemicals. For the RH-531-treated Anza and Yecora 70 and the RH-532-treated Anza, more than 94% of the seeds produced by open-pollination on treated plants were from self-or sib-pollination as determined by progeny testing. However, RH-532-treated Yecora 70 and RH-2956-treated Anza and Yecora 70 did result in more crossed seeds, with a maximum of 20% outcrossing. It was believed that spike compactness induced by the chemicals and the related poor flower opening were the major limitations for outcrossing. Artificial pollinations made to the test varieties showed that RH-531 induced both male and female sterility and was undesirable for practical use. RH-532, however, could be applied at the booting stage to avoid severe female sterility, and RH-2956 clearly was the best of the three chemicals, with the female fertility very close to those of the untreated checks of both Anza and Yecora 70. Of the three chemicals, RH-2956 gave the highest percentage of hybrid plants in the progeny of hand-or open-pollinated spikes. Its practical use for hybrid seed production, however, will depend largely on improvement of methods to increase cross pollination in wheat. 相似文献
5.
Seedling emergence,coleoptile length,and plant height relationships in crosses of dwarf and standard-height wheats 总被引:2,自引:0,他引:2
Summary Seedling emergence was closely correlated with coleoptile length and plant height among parents, F2 and F3, populations of crosses involving dwarf wheats Olesen Dwarf (CI 14497), Norin 10 derivative D6301, Tom Thumb derivative D6899, and the standard-height varieties Ramona 50 and Nainari 60. Genetic mechanisms that governed plant height also influenced coleoptile length, but the relative effects of genes showing dominant or epistatic effects appeared to be different. With respect to the two parents involved in each of 15 crosses, mean F2 coleoptile lengths were consistently closer to the low parent value than were corresponding mean F2 plant heights. A slight curvilinear relationship was also found between coleoptile length and plant height of F3 lines. The results suggest that selection of semidwarf wheats with long coleoptiles and improved emergence properties from crosses involving the dwarf wheats of this study would be unlikely. 相似文献
6.
7.
研究和探讨了虾加工副产物的酶解产物(Enzymatic Hydrolysis Production,EHP)对蛋鸡产蛋率和蛋品质的影响。以虾加工副产物为原料,应用复合生物酶酶解技术制备EHP,选择产蛋率在80%以上的300日龄笼养褐壳蛋鸡288只,随机分成3组,在基础日粮中分别添加0、1.5g/100g、3g/100g虾加工副产物EHP,并替代相应重量的鱼粉,试验期为60天。EHP,可显著提高鸡蛋的哈夫单位(P〈0.05),试验组蛋鸡产蛋率平均提高3.14%,料蛋比相应低于对照组。表明虾加工副产物EHP可显著提高产蛋高峰期过后处于衰减期的鸡蛋的哈夫单位及产蛋率。 相似文献
8.
甘蓝型油菜高含油量隐性胞核雄性不育两型系的选育 总被引:2,自引:0,他引:2
采用复合回交方法,选育出甘蓝型油菜双低隐性核不育两型系。双低不育系121AB、123AB、175AB、932AB、933AB等表现高含油量、产量高等性状,品质优良。其中175AB、932AB、933AB含油量42.7%~44.0%,蛋白质含量24.2%~25.3%。组配的德油系列优质杂交油菜新组合在比较试验中均比对照种油研七号增产,增产率9.98%~27.34%,表现出较大的增产潜力。 相似文献
9.
高新技术在茶叶加工中的应用 总被引:1,自引:0,他引:1
本文简述了膜分离技术,超临界流体萃取技术,冷杀菌技术及真空冷冻干燥等新技术的基本原理及其在茶叶加工中的应用状况。 相似文献
10.