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针对当今天然纤维制酒精的研究中天然纤维水解糖化过程面临的种种技术问题,提出了探索一种利用木腐型食用真菌转化法水解糖化天然纤维的研究途径,并从八个方面论证了实现该途径的可行性. 相似文献
113.
Y. A. Nanja Reddy M. N. Keshava Murthy K. Virupakshappa R. Uma Shaanker 《Journal of Agronomy and Crop Science》1995,175(2):83-86
Measurement of total leaf area per plant in crop improvement programmes for a variety of purposes is often very tedious and time consuming. In this paper, we offer a rapid and non-destructive method of estimating the total leaf area in sunflower at the time of anthesis. We show that multiplying the leaf area of a specific leaf position from the apex by the total number of leaves per plant yields total leaf area with more than 95 % accuracy. The specific leaf position for any given genotype in sunflower can be arrived at by multiplying the total number of leaves per plant by the factor 0.355 and rounding off to the nearest highest integer. This technique can be used for the rapid estimation of leaf area per plant at anthesis for any given genotype of sunflower. 相似文献
114.
血耳是民间极感性趣的一种药用兼食用菌。本文从温度、湿度、pH、光线、水份、碳源、氮源、培养代料等因子对血耳菌丝生长原基分化、出耳的影响进行了生物学特性方面的研究,为开发利用血耳,进行人工栽培提供资料。 相似文献
115.
Forty-five accessions of sunflower collected from different countries were screened for salinity tolerance after 2 weeks growth in sand culture salinized with 150 meq l?1 of NaCl2+ CaCl2 (1:1 ratio equivalent wt. basis) in half strength Hoagland's nutrient solution. The results for plant biomass of 45 accessions show that there was considerable variation in salinity tolerance. In a further greenhouse experiment, the salinity tolerance of three tolerant (HO-1, Predovik, Euroflor) and two sensitive (SMH-24, 9UO-985) lines (selected on the basis of their performance in the seedling experiment) was assessed at the adult stage to evaluate the consistency of salinity tolerance at different growth stages. All three salt tolerant accessions produced significantly greater plant biomass, seed yield and seed oil content than the salt sensitive accessions. The tolerant accessions accumulated less Cl? and more K+ in the leaves under saline conditions compared with the salt sensitive accessions. The salt tolerant accessions also maintained relatively high leaf K:Na ratio and K+ versus Na+ selectivity. Although statistically nonsignificant, all three tolerant accessions had greater soluble carbohydrates, soluble proteins, total free amino acids and proline in the leaves than the sensitive accessions. A field trial conducted in a salt-affected field confirmed the greenhouse results of the selected accessions. This study shows that salinity tolerance of sunflower does not vary with stage of plant cycle, so selection for increased salt tolerance can be carried out at the initial growth stage. Secondly, it is found that there is great variation of salt tolerance in sunflower. Low uptake of Cl?, high uptake of K+, and maintenance of high K:Na ratios and K+ versus Na+ selectivity in the leaves and possibly the accumulation of organic osmotica such as soluble carbohydrates, soluble proteins, proline and free amino acids seem to be the important components of salt tolerance in sunflower. 相似文献
116.
本文分析了湖南省食用菌生产的现状及发展趋势,对食用菌生产的布局、重点等问题进行了探讨,并对今后食用菌的发展提出了若干建议。 相似文献
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食用菌育种方法的研究现状·存在的问题及展望 总被引:1,自引:0,他引:1
综述了食用菌选择育种、杂交育种、诱变育种、原生质体融合育种与基因工程育种的研究进展。对育种方法的运用进行了展望,认为随着分子生物学的快速发展,杂交育种等常规育种方法结合DNA分子标记辅助选择育种是今后食用菌育种的主要发展方向。 相似文献
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