Mixed systems of agriculture incorporating combinations of trees and crops have formed key elements of the landscape of Europe throughout historical times, and many such systems continue to function ...in the present day. In many cases they represent formerly widespread traditional systems in decline and a number have already become extinct or exist only in a threatened state. The causes are both practical and economic. The agricultural subsidy regime within the European Union is presently unfavourable towards silvoarable practices, which has been a major factor in their recent decline. The silvoarable systems of Europe can be split into two classes according to location - northern Europe and the Mediterranean. The latter contains not only a greater area of silvoarable cultivation, but also a greater diversity of systems due to the broader range of commercial tree and crop species grown. In general, the systems of northern Europe are limited by light, whilst those of the Mediterranean are limited by the availability of water. Mixed systems of agriculture present an opportunity for future European rural development and have the potential to contribute towards the increased sustainability of agriculture and enhancement of biodiversity, whilst preserving landscapes that are both culturally important and aesthetically pleasing. A better understanding of the legacy of traditional silvoarable systems, combined with the formulation of a consistent definition and specific European policy towards them will be invaluable in ensuring that the benefits of mixed agriculture are fully exploited in the future.PUBLICATION ABSTRACT
An experiment comparing the fresh and dry matter yields of four willow cultivars (Ulv,
Salix viminalis, Jorr,
S. viminalis, Tora,
S.
viminalis
×
S.
schwerinii
and Ashton Stott,
S.
viminalis
×
S.
...burjatica
) at four planting densities (10,000, 15,000, 20,000 and 25,000
plants
ha
-
1
)
was established within a commercial SRC plantation in northern England. Data are presented for the first cut one year after planting (2001) and for a harvest after one complete growth cycle of three years (2004) and for annual yield production. There were significantly higher yields with increased density, and there were significant differences between cultivars. The cultivar Ashton Stott gave considerably higher fresh and dry yields than Ulv, Jorr and Tora, despite having a lower percentage dry matter content, with annual yields exceeding
10
t
oven dry
matter
ha
-
1
yr
-
1
at the highest two densities.
▶ Yields of tomato fruits were increased by addition of poultry manure to the growth medium. ▶ The fruit concentration of zinc was increased by supply of poultry manure to the plants. ▶ The fruit ...concentration of potentially harmful bromide was decreased by supply of poultry manure. ▶ Fruit calcium concentration was decreased by poultry manure, but not enough to risk blossom end rot.
Poultry manure (PM) must be disposed of from poultry farms, but is a potentially valuable source of macro- and micronutrients for plant growth. The objective of this study was to examine the effects of poultry manure on the growth of tomato (
Lycopersicon esculentum) plants. Yields of fruits and vegetative material of plants grown in soil with 0, 10, 20 and 40
g
kg
−1 PM added were measured. Concentrations of N, P, K, Ca, Mg, S, Fe, Zn, Cu, Mn, Mo, Cl, Si, Br, Rb, Sr and Ba in leaves at flowering and at final harvest and in fruits were determined by polarized energy dispersive X-ray fluorescence (PEDXRF). Poultry manure fertilization improved tomato shoot growth and also fruit yield and increased leaf N concentrations at the harvest stage. In addition, P concentrations of the leaves and fruits were increased as the application rate of PM was increased. Fruit Ca and Mg were significantly reduced by increased rate of PM application, but not to the extent to cause the calcium deficiency disorder blossom end rot. Applied high levels of PM slightly increased the concentrations of leaf Mo and Br at the harvest stage. Poultry manure applications had a positive effect on the concentrations of leaf Zn, Cu, Cl and Rb at both sampling stages, but leaf Si concentration was reduced by PM treatments. The concentrations of Zn and Rb were increased in the fruits by PM treatments, but the concentrations of Br were decreased. Applied PM levels had no significant effects on the concentrations of K, S, Fe, Sr or Ba in tomato plants. It is concluded that the increased fruit yield, and the increased concentration of Zn (an element required in the human diet) and the lowered concentration of potentially harmful Br in the fruit make poultry manure a valuable growing medium for tomato production.
We tested the hypothesis that induction of cyclo‐oxygenase (COX) 2 mediates some effects of bone morphogenetic protein (BMP) 2 on bone. BMP‐2 induced COX‐2 mRNA and prostaglandin (PG) production in ...cultured osteoblasts. BMP‐2 increased luciferase activity in calvarial osteoblasts from mice transgenic for a COX‐2 promoter‐luciferase reporter construct (Pluc) and in MC3T3‐E1 cells transfected with Pluc. Deletion analysis identified the −300/−213‐bp region of the COX‐2 promoter as necessary for BMP‐2 stimulation of luciferase activity. Mutation of core‐binding factor activity 1 (muCbfa1) consensus sequence (5′‐AACCACA‐3′) at −267/−261 bp decreased BMP‐2 stimulation of luciferase activity by 82%. Binding of nuclear proteins to an oligonucleotide spanning the Cbfa1 site was inhibited or supershifted by specific antibodies to Cbfa1. In cultured osteoblasts from calvariae of COX‐2 knockout (−/−) and wild‐type (+/+) mice, the absence of COX‐2 expression reduced the BMP‐2 stimulation of both ALP activity and osteocalcin mRNA expression. In cultured marrow cells flushed from long bones, BMP‐2 induced osteoclast formation in cells from COX‐2+/+ mice but not in cells from COX‐2−/− mice. In vivo, BMP‐2 (10 μg/pellet) induced mineralization in pellets of lyophilized collagen implanted in the flanks of mice. Mineralization of pellets, measured by microcomputed tomography (μCT), was decreased by 78% in COX‐2−/− mice compared with COX‐2+/+ mice. We conclude that BMP‐2 transcriptionally induces COX‐2 in osteoblasts via a Cbfa1 binding site and that the BMP‐2 induction of COX‐2 can contribute to effects of BMP‐2 on osteoblastic differentiation and osteoclast formation in vitro and to the BMP‐2 stimulation of ectopic bone formation in vivo.
Tomato (Lycopersicon esculentum) plants were grown in hydroponic culture with nitrogen (N): phosphorus (P) supply ratios from 18:1 to 2:1. Nitrate and phosphate were supplied daily in pre-set ratios ...to maintain a constant P concentration, giving varying degrees of N limitation. Plant dry weight, weights of plant fractions and N and P concentrations in plant parts were measured at 9 and 18 days. Relative growth rate was related to ratio of N:P supplied, with higher ratios giving a higher growth rate, but a noticeably reduced rate was only apparent at 4:1 and 2:1 ratios. Relative growth rate was largely independent of internal N and P concentrations, although there was an optimum internal N:P ratio of approximately 14:1. The plants took up N and P at rates adjusting towards this 14:1 ratio. Depressed relative growth rate of plants inadequately supplied N was linearly correlated with decreased shoot fraction.
Alfalfa crops were grown in the field at the University of Ankara (473939 E, 4385149 N), over two seasons between 2001 and 2003 with sulfur (S) supplied at two different rates. The experimental ...design was a randomized complete block with five replicates and three cutting dates in each season. Sulfur was applied at rates of 0 (control), 160 (S1), and 240 (S2) kg ha-1 as gypsum. Alfalfa hay was harvested three times each year, and the concentrations of elements in the hay were measured by polarized energy dispersive x-ray fluorescence (PEDXRF). Sulfur fertilization increased S concentrations and improved alfalfa hay yield for both years. Applied S slightly reduced phosphorus (P) and magnesium (Mg) concentrations in the first year and had no significant effect on the potassium (K) and calcium (Ca) concentrations of alfalfa hay for either year. The highest S (240 kg ha-1 S) level increased sodium (Na) concentrations in the first year but decreased them in the second year. Sulfur application also decreased chloride (Cl) concentration in the first year. Molybdenum (Mo) concentration of the alfalfa was significantly reduced by S1 treatment in year 1. Iron (Fe) concentration was increased by S2 treatment in the second year, and zinc (Zn) concentration was increased by S1 treatment in the first year. However, applied S had no effect on manganese (Mn), copper (Cu), titanium (Ti), vanadium (V), cobalt (Co), nickel (Ni), barium (Ba), uranium (U), and lead (Pb) concentrations for either year. Applied S decreased aluminum (Al) and silicon (Si) and increased bromine (Br) and rubidium (Rb) concentrations of alfalfa in the first year. In addition, strontium (Sr) concentration was increased by S2 treatment in the first year but was decreased in the second year. The stage of cutting greatly affected mineral concentrations. Compared with the first cutting, S concentrations were higher in the second and third harvest for both years. In general, the concentrations of P, Mg, Na, Cl, Mo, Ti, V, Br, Co, Ba, Sr, Rb, U, and Pb were increased, whereas the concentrations of Fe, Zn, Mn, Cu, and Ni were decreased with later cutting. The concentrations of K and Ca did not vary between cuts.
Seeds of sorghum Sorghum bicolor (L.) Moench cv 'Wrangler' dressed with three increasing concentrations of an iron ethylenediamine-di-O-hydroxphenylacetic acid (FeEDDHA) product up to 480 mg Fe kg- 1 ...seed as a sole source of iron supply as well as a treatment without any dressing were grown for 19 days after germination in sand culture buffered to pH 8 by calcium carbonate. Nitrogen was supplied either as ammonium (NH4)-N or nitrate (NO3)-N, the former being supplemented with nitrapyrin (N Serve) to prevent nitrification. Chlorosis of the younger leaves was evident in all treatments except at the two higher levels of NH4-supplied plants. Dry matter yields of the shoots were raised only relatively slightly by the increasing levels of Fe supply and at each level the NH4 form was superior to that of NO3 -N. At the end of the growth period the pH of the sand around the roots had fallen by about 0.5 of a unit for NH4-fed plants and increased by about 0.2 of a unit for NO3-fed plants. At each level of Fe supply, NH4 nutrition approximately doubled the micronutrient Fe, zinc (Zn), copper (Cu), manganese (Mn) shoot concentrations and uptakes as compared with NO3-nutrition. For the NO3 -fed plants, increasing rates of Fe seed dressing had little effect on shoot Fe concentrations or uptakes, the concentration values determined (about 40 μ g g- 1 dry wt.) being below the range of critical deficiency concentration. Similarly concentrations of Mn were also in the deficiency range in the seed dressed NO3-fed plants (11-12 μ g g- 1 dry wt) so that in the NO3 treatments chlorosis may have resulted from a lack of Mn as well as Fe. Dressing sorghum seeds with Fe chelates in conjunction with NH4 fertilization supplemented with an inhibitor to prevent nitrification would appear to be a worthwhile approach to ensure an initial source of Fe to the young developing plant in the avoidance of iron-induced chlorosis in the growth of sorghum on high pH calcareous soils.
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