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本文分析了现阶段我国人民的食物结构以及食品加工在开发蛋白质食物开源中的地位和作用,并从五个方面进行了论述。 相似文献
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柞蚕肠液理化性质与饲料效率的相关性研究 总被引:2,自引:0,他引:2
对柞蚕肠液的理化性质与饲料效率的相关性进行研究的结果表明 :柞蚕肠液对促进蚕体抗病与消化吸收功能有着重要作用 ,平均每头蚕有肠液 1 76mL ,品种间开差为 0 78mL ,相对开差 5 7 80 % ,肠液量越多 ,饲料效率越高 ;柞蚕不同品种肠液pH平均值未发现明显差异 ,但强健好养饲料效率高的品种个体间开差小 ;柞蚕肠液缓冲力除与品种强健性有关外 ,还与品种的饲料效率呈正相关 ,在强健丰产与高饲料效率品种中 ,肠液恢复pH原值所需时间越短 ,饲料效率越高 ,电刺法取出肠液后 ,肠液恢复缓冲力所需时间是恢复其pH原值时间的 1 8倍多 ,同恢复肠液pH原值所需时间长短与品种强健性和饲料效率的关系完全一致。 相似文献
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合理调整我国人民的食物结构是提高全民族身体素质,推进社会文明进步,具有深远的战略意义的一项国策。调整国民食物结构是一个科学性,政策性很强,社会涉及面广,地区人群民食习惯差别大的极为复杂的动态系统工程。作者针对山西省情实际,从追朔我国饮食传统,膳食民习,食物资源及演变趋向探求,提出合理调整山西人民食物结构的策略与途径。 相似文献
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Z. Ngoko K.F. Cardwell W.F.O. Marasas M.J. Wingfield R. Ndemah F. Schulthess 《European journal of plant pathology / European Foundation for Plant Pathology》2002,108(9):893-902
The aim was to identify biological and physical factors responsible for reducing maize yield in Cameroon. Two surveys were conducted in 137 fields in two agroecological zones in 1995–1997. In the Humid Forest (HF), Bipolaris maydis, Stenocarpella macrospora, Puccinia polysora, Rhizoctonia solani and soil fertility were factors that reduced maize production in 1995 and 1996. In the Western Highlands (WHL), Cercospora zeae-maydis, and the interaction between soil fertility and maize variety were the most important constraints to maize production in 1996. In 1997, C. zeae-maydis, S. macrospora, physiological spot and stem borer damage (Busseola fusca) were negatively related to ear weight. The combination of these biological factors (diseases and insects), and the physical parameter of soil fertility were responsible for reducing maize yield in these selected benchmarks of Cameroon. Maximum potential yield reductions were estimated at 68% due to B. maydis and 46% due to S. macrospora, respectively, in the HF in 1995. In 1996, maximum potential yield reductions in the HF were estimated at 34%, 41% and 30% due to S. macrospora, P. polysora and R. solani, respectively. In the WHL, C. zeae-maydis had the potential to cause a yield reduction of 79% in 1996. In the WHL in 1997, the interaction between C. zeae-maydis and B. fusca, stem diseases and the physiological spot caused potential reductions of 52%, 34% and 39%, respectively. 相似文献
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检测了黑龙江水稻主产区4个当地主栽品种的种子内部镰刀菌寄藏情况,测定了20%克福甲和20%克多甲种衣剂对种子带菌消毒处理效果及对水稻串珠镰刀菌(Fusarium moniliforme)的抑菌作用和联合毒力,并借助扫描电镜观察了上述2种混配种衣剂对串珠镰刀菌的形态毒理影响。结果表明,种子内部镰刀菌的分离频率高达56.7%~96.0%,其中串珠镰刀菌的分离频率为32.6%~48.2%,2种种衣剂对带菌种子具有显著的消毒处理效果。20%克福甲和20%克多甲种衣剂对镰刀菌F.moniliforme的毒力指数分别为457.11和802.04,增效倍数分别为6.53和0.13。20%克多甲种衣剂(多菌灵:甲基立枯磷为5:5,W/W)对串珠镰刀菌的抑菌作用优于20%克福甲种衣剂(福美双:甲基立枯磷为8:6,W/W),增效作用低于20%克福甲种衣剂。电镜观察表明,种衣剂低浓度至高浓度处理下均可引起串珠镰刀菌菌丝不同程度的异常生长,表现为主菌丝局部膨大或形成菌丝束,菌丝顶端异常膨大、缢缩或形成穗状和花絮状分枝。 相似文献
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Infection processes of Pyrenophora semeniperda on seedling and adult wheat leaves and wheat ears were investigated. Almost 100% germination of conidia occurred on seedling leaves, compared with 20–30% on adult leaves. Appressoria formed over the anticlinal epidermal cell walls and haloes always accompanied infection. Sometimes papillae formed within the leaves as a resistance mechanism. Infection hyphae ramified through the intercellular spaces of the mesophyll resulting in cellular disruption. The infection processes on floral tissues were similar to those observed on leaves; however, no infection occurred on anther, stigmatic or stylar tissues. Infection of ovarian tissue occurred both with and without appressoria formation. Hyphae grew mainly in the epidermal layers and appeared unable to breach the integumental layer as no growth was observed in endosperm or embryo tissues. The optimum dew period temperature for conidial germination was 23·6°C, compared with 19·9°C for lesion development, 20·4°C for the production of infection structures on seedling leaves and 23·7°C for floret infection. Leaf disease development occurred in a logistic manner in response to dew period, with maximum infection observed after 21 h compared with > 48 h in seeds. An initial dark phase during the dew period was necessary for infection and temperature after the dew period had an effect, with significantly more numerous and larger lesions being formed at 15°C compared with 30°C. Seedling leaves were found to be more susceptible than older leaves, under both field and controlled environment conditions. Infection of wheat seeds following inoculation of ears, or after harvest burial of inoculated disease-free seeds, was demonstrated. In the latter, 3-week-old seedlings were slightly stunted, whereas older plants were unaffected. The apparent unimportance of this plant pathogen as a cause of leaf disease in relation to its poor adaptation to dew periods and dew period temperature is discussed, along with the importance of its seed borne characteristics. 相似文献
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