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1.
Sainfoin (Onobrychis viciifolia) is a temperate legume that contains condensed tannins (CT), i.e., polyphenols that are able to bind proteins and thus reduce protein degradation in the rumen. Few studies have investigated the relation between plant phenology, CT characteristics and nutritive value of sainfoin. In this study we investigated differences among three sainfoin varieties (Esparcette, Ambra and Villahoz) that were of different geographical origin, and which were cultivated at the same site over the course of two growth cycles and compared with a tannin‐free legume, lucerne (Aubigny). Plants were harvested on nine dates in the first and four dates in the second growth cycle. Phenological stages were analysed for leaf‐to‐whole‐plant ratio, nitrogen (N), organic matter digestibility (OMd) by the pepsin‐cellulase method, cell‐wall concentration, N solubility (solN) plus CT concentration, biological activity and structures. Leaf‐to‐whole‐plant, cell‐wall concentration, N of sainfoin and lucerne were closely related to the phenological stage. Although sainfoin developed earlier than lucerne, its pepsin‐cellulase digestibility was higher than or close to lucerne. Esparcette had the lowest OMd, N and solN and the highest CT concentration. CT concentration, proportion of prodelphinidins (PD) and mean degree of polymerization (mDP) increased with the phenological stage (or plant maturity), and these parameters were associated with lower biological activity of CT. Sainfoin varieties differed in their relationships between phenological stages, nutritional parameters and CT characteristics. The results demonstrated that sainfoin can be a valuable alternative forage legume to lucerne.  相似文献   

2.
Anaerobic digestion of biomass produces biogas for combustion and also provides a residual digestate. Although sometimes regarded as a waste product, the nutrient‐rich chemical composition of digestate makes it a potential organic fertilizer for agriculture. The goal of this study was to evaluate the effectiveness of digestate as a fertilizer on the biomass yield and chemical composition of cocksfoot (Dactylis glomerata L.). In a 5‐year small‐plot field experiment digestate fertilization treatments supplying 90, 180, 270, 360 and 450 kg N ha?1 were compared with untreated plots and plots fertilized with 180 kg N ha?1 of mineral N fertilizer. Swards fertilized with digestate produced higher biomass yield compared with the control. The same rate of nitrogen fertilizer (180 kg N ha?1) supplied as digestate and from mineral fertilizers gave similar results on biomass yield. Herbage in swards fertilized with digestate contained less nitrogen, but the C:N ratio was much more suitable for biogas production. Digestate fertilization resulted in higher concentrations of cellulose and hemicellulose in biomass and lower contents of the inhibitors of anaerobic digestion—sulphur, calcium, magnesium and phosphorus—compared with those of swards receiving mineral fertilizers.  相似文献   

3.
Forage maize grown in areas where spring temperatures are low and accumulated heat is limited will be restricted in terms of maturity and thus nutritional value. A stagnant growth phase is commonly caused by low temperatures between germination and the five-leaf stage, which could be caused by reduced mineral availability. The effects on maize plant development and harvest characteristics of supplying phosphorus and zinc to young plants in a foliar spray were investigated. Three different application dates, between the four-leaf and the seven-leaf stage, were compared. Applying the phosphorus and zinc foliar spray at the four-leaf stage resulted in a significant ( P  < 0·05) increase in starch content at harvest. Cob index [proportion of plant dry matter (DM) in the cob] was increased ( P  < 0·05) by applying the nutrient spray at the four-, five- and seven-leaf stages. However, there was no effect on DM yield, suggesting some alteration in partitioning within the plant.  相似文献   

4.
This study examined the relationships between botanical composition and forage parameters (yield and forage quality variables) in 153 permanent grasslands located in the Massif Central of France. Grasslands were sampled at two vegetation stages in the first growth cycle. Botanical composition, yield, ash, crude protein, neutral detergent fibre, acid detergent fibre, acid detergent lignin, organic matter digestibility (OMD) and voluntary intake (VI) were estimated for each sample. Temporal variability in species–forage parameter relationships were accounted for using innovative multivariate analyses applied mainly in ecological science. Crude protein and OMD were weakly correlated when each harvest time was analysed separately. Species–forage parameter relationships remained stable during the first growth cycle. The stability of these relationships indicates that permanent grasslands dominated by competitive species were associated with high yield and forage quality values whereas permanent grasslands composed of conservative species and/or high proportions of senescent material were associated with high structural carbohydrate values and low yield, OMD and VI values. Based on these relationships, we propose a typology of permanent grasslands along with a set of indicator species enabling non‐specialist botanists to easily classify grasslands for grassland management purposes.  相似文献   

5.
Four selections of three amaranth species were used in the study:A. cruentus (US Rodale 82S-1034),A. hypochondriacus (US Rodale 81S-1024).A. caudatus (Cusco, Peru CAC-2002) andA. cruentus (GUA-17). These were fertilized with levels of 0, 30, 60 and 90 kg/ha of a 12-24-12 fertilizer formulation applied to experimental plots 3×4m2 in four replications. The harvested grain was used for protein and fat analysis, and for protein quality evaluations on raw and on heat processed samples.A. cruentus (US) andA. hypochondriacus flowered at 43–44 days at 60 and 43cm, respectively,A. caudatus (Peru) at 51 days and 65cm, andA. cruentus (Gua) at 50 days and 80cm height. Days at harvest varied from 100 to 129 days at heights of 125 to 180cm. Yield of grain fromA. hypochondriacus (US) andA. cruentus (Gua) was higher than forA. cruentus (US) andA. caudatus, but did not differ for each pair. although not influencing yield, the application of fertilizer increased protein content forA. caudatus (Peru) from 12.35 to 14.50%; but not the protein content of the other selections. The fat content was affected differently in all four selections. The application of fertilizer did not affect protein quality either in raw or processed grain. On the other hand, processing increased protein quality, food intake, and animal performance significantly most clearly seen withA. cruentus (US) andA. caudatus (Peru) and to a lesser extent forA. hypochondriacus (US) andA. cruentus (Gua)). The data obtained showed inconsistent effects on yield and chemical composition, and no effect on protein quality with fertilizer application.  相似文献   

6.
Effects of season (SEAS), organic fertilization with laying hen manure (N) and harvest frequency (FREQ) on forage yield and composition were evaluated in a high‐density mulberry forage bank, established under low‐input tropical farming conditions. The experiment, replicated over two consecutive years, was arranged in 18 treatments resulting from a 3 × 3×2 factorial design which combined three FREQ (60, 90 and 120 d), 3 N rates (100, 300 and 500 kg N ha?1 year?1) and the two seasons (RAIN and DRY). Forage yield, leaf‐to‐stem ratio, the edible fraction (EDIB, %), nutrient content and the maturity indexes were monitored. Either forage yield or qualities by plant fraction were strongly affected by SEAS, FREQ, N rate and by their interactions. Effects of FREQ and N were modulated by SEAS. Increasing FREQ during RAIN negatively affected EDIB yield and quality after 90 d, while increasing ligneous fraction. During DRY, longer FREQ allowed higher total forage and EDIB yields. Leaves were more abundant in RAIN, and its yield was increased with fertilization but only during this season. Maturity indexes were higher in DRY than in RAIN. Under the conditions of this experiment, harvesting at 60 and 90 d in RAIN and DRY, respectively, with an N rate of 300 kg N ha?1 year?1 seems the best agronomic choice for an optimal compromise between forage yield and nutritive value.  相似文献   

7.
Grassland systems frequently exhibit small‐scale botanical and structural heterogeneity with pronounced spatio‐temporal dynamics. These features present particular challenges for sensor applications, in addition to limitations posed by the high cost and low spatial resolution of many available remote‐sensing (RS) systems. There has been little commercial application of RS for practical grassland farming. This article considers the developments in sensor performance, data analysis and modelling over recent decades, identifies significant advances in RS for grassland research and practice and reviews the most important sensor types and corresponding findings in research. Beside improvements of single sensor types, the development of systems with complementary sensors is seen as a very promising research area, and one that will help to overcome the limitations of single sensors and provide better information about grassland composition, yield and quality. From an agronomic point of view, thematic maps of farm fields are suggested as the central outcome of RS and data analysis. These maps could represent the relevant grassland features and constitute the basis for various farm management decisions at strategic, tactical and operational levels. The overarching goal will be to generate low cost, appropriate and timely information that can be provided to farmers to support their decision‐making.  相似文献   

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