排序方式: 共有2条查询结果,搜索用时 0 毫秒
1
1.
Abstract Green manure legumes are often used to compare biomass production as well as nitrogen-fixing capacity. Mineral deficiency often limits the symbiotic nitrogen fixation of many legumes, thus limiting their productivity despite their high yielding potential (O’Hara et al. 1988; Flis et al. 1993). Leguminous species require large amounts of P for growth, nodulation, and nitrogen fixation. Consequently, they are often unable to grow in acid soils with low available P. The low P availability in tropical acid soils often arises from fixation of P by Al and Fe in soil. Generally, Al and Fe-phosphates are relatively unavailable to plants (McLachlan 1976; Ae et al. 1990). 相似文献
2.
Instar 1 and 2 Jasus edwardsii (Decapoda; Palinuridae) phyllosoma larvae were fed an artificial diet formulation (based on fish and mussel) consisting of three different gelatin combinations (firm, 4% inclusion; medium, 2% inclusion; and soft, no gelatin). The diet contained ytterbium oxide (Yb2O3; 1% inclusion), an inert heavy metal marker, which was used to confirm diet consumption in instar 1 and 2 phyllosoma. Over a 6‐h feeding period, instar 1 phyllosoma showed a preference for the soft and medium diets as opposed to the firm diet, but this effect was not significant with instar 2. The artificial diets remained palatable over the duration of the experiments, suggesting leaching did not influence diet attractiveness. It is suggested that diets comprising softer food items such as microencapsulated pellets or gelatinous formulated diets and pastes are most suitable for early‐instar phyllosoma. Furthermore, it is also suggested that Yb2O3 is a potentially useful marker for ongoing quantitative work on diet utilization in lobster larvae. 相似文献
1