scholarly journals Boron deficiency in eucalypt plantations in China

1994 ◽  
Vol 24 (12) ◽  
pp. 2409-2416 ◽  
Author(s):  
B. Dell ◽  
N. Malajczuk

Boron deficiency is identified as one of the more important causes of poor stem form and malformed leaves in plantations of Eucalyptusglobulus in Yunnan Province, and of Eucalyptusgrandis, Eucalyptustereticornis, and Eucalyptusurophylla in Guandong Province. Symptoms of B deficiency in E. globulus were rolled and malformed leaves, stem dieback, and a prostrate form. In E. urophylla, leaf margins became chlorotic then necrotic, leaves turned brittle and corky, shoots died back, and the upper stem nodes were enlarged supporting numerous short-lived axillary shoots. In E. grandis, stem dieback was preceded by the basipetal accumulation of anthocyanin in leaves. Boron-deficient E. tereticornis leaves developed marginal and interveinal chlorosis and recurved margins. Depressed foliar B concentrations were associated with visible symptoms. In E. globulus, the mean B concentration in young leaves of healthy trees was 31 mg/kg dry matter compared with 10 mg/kg in prostrate trees. Symptoms did not appear in E. globulus trees supplied with B fertilizer at planting. Normal shoot growth was restored in E. urophylla by the addition of B to the soil.

1975 ◽  
Vol 23 (3) ◽  
pp. 459 ◽  
Author(s):  
RL Specht ◽  
YM Brouwer

Field data, collected at fortnightly intervals over a period of three years, show a distinctly bimodal rhythm in the shoot growth of Eucalyptus species in the Brisbane area of Queensland. Maximum growth occurs in autumn and spring; growth is reduced during summer and, apart from periods of warmer weather, virtually ceases during winter. The bimodal growth rhythm is due to the interacting influence of unimodal curves relating monthly values for dry matter production of the leaf canopy to the respective effects of mean daily temperature, intensity of solar radiation, and available water. When the mean monthly temperature falls below 16-18°C, most photosynthates are translocated to stems and roots: little canopy growth then occurs, thus accentuating the winter depression in shoot growth. Shoot growth in the Brisbane region is compared with that observed in other areas of Australia. Shoot growth is minimal in plant communities dominated by: (a) arid to subhumid species of Acacia when the mean monthly temperature falls below 24-26°C (b) Eucalyptus spp., Myoporum sp., Heterodendrum sp. and dominant heath species when the mean monthly temperature falls below 16-18° (c) Acmena smithii (at least at Wilson's Promontory) and Leptospermum myrsinoides when the temperature falls below 13-14° (d) Pinus radiata when the temperature falls below 10°. In contrast, Nothofagus cunninghamii shows little shoot growth when the temperature rises above 16°.


2005 ◽  
Vol 83 (6) ◽  
pp. 851-859 ◽  
Author(s):  
Stephen J Trumble ◽  
Michael A Castellini

To determine the effects of diet mixing on digestive performance, harbour seals (Phoca vitulina L., 1758) were offered either pure diets of Pacific herring (Clupea pallasii Valenciennes, 1847) or walleye pollock (Theragra chalcogramma (Pallas, 1814)) or a 1:1 mix of herring and pollock. Regardless of diet, retention time decreased approximately 40% as intake quadrupled. The mean apparent digestible dry matter (ADDM) was greatest on mixed diets during low feeding frequency trials; ADDM during high feeding frequency trials was significantly reduced as intake increased for animals on the single-species (pollock or herring) diets. As intake increased, up to 45% more digestible energy was assimilated from the mixed diet than from either single-species diet. The findings of this study suggest that a mixed diet consisting of prey differing in lipid and protein amounts increased digestible energy intake in harbour seals. Our measures of intake and ADDM in harbour seals revealed digestive flexibility and indicated that digestion in harbour seals was more efficient on a mixed diet.


2016 ◽  
Vol 56 (11) ◽  
pp. 1897 ◽  
Author(s):  
C. A. Ramírez-Restrepo ◽  
H. Clark ◽  
S. Muetzel

Daily methane (CH4) emissions (g) and CH4 yield (g/kg dry matter intake) were measured from 10 dairy heifers (<1 year old) and nine rumen-fistulated cows (>6 years old) fed ryegrass (Lolium perenne) chaffage indoors. The CH4 emissions were estimated using the sulfur hexafluoride tracer technique in four ~5-day periods beginning in June 2008 and repeated 4, 6 and 7 months later. Respiratory chambers were used in four ~13-day periods beginning in November 2008 and repeated 2, 5 and 6 months later. Third and fourth sulfur hexafluoride tracer periods overlapped with the first and second chamber measurement periods, respectively. Averaged over the four measurement periods the CH4 yields determined using both techniques were similar for heifers and cows. The mean CH4 yield estimated by the sulfur hexafluoride tracer technique was 25.3 ± 0.52 for heifers and 24.1 ± 0.55 for mature cows, whereas the mean CH4 yield measured in respiratory chambers was 23.7 ± 0.66 for heifers and 23.6 ± 0.66 for mature cows. Averaged over the eight measurements irrespective of technique, CH4 yields for heifers (24.5 ± 0.42) and cows (23.8 ± 0.43) were similar. There was also no difference between CH4 methods for assessing CH4 yield during the overlapping measurement periods. It was concluded that no consistent differences in CH4 yield existed between heifers and mature cows. Therefore, we do not recommend adoption of an age-related emission factor for cattle in the national inventory calculations for New Zealand.


1957 ◽  
Vol 35 (3) ◽  
pp. 195-202 ◽  
Author(s):  
M. A. A. Vonk ◽  
L. W. McElroy ◽  
R. T. Berg

Four treatments, involving differences in method of feeding and interval between last feed and slaughter, were employed in a study of the effect of dietary chlortetracycline on protease, amylase, and cellulase activity in the intestinal and cecal contents of 16 pairs of weanling pigs. Most consistent results were obtained with six pairs which were limited pair-fed except for the final feeding during which feed was available ad libitum for a 4-hour period ending 18 hours before slaughter. The mean total activities of all three hydrolases in the contents of the small intestines and of the ceca of the antibiotic-fed animals of these six pairs were significantly greater than in those of the control animals. Expressed as activity per gram dry matter of intestinal contents, significantly higher values for protease and amylase, but not for cellulase, were observed in the pigs that had received chlortetracycline. When the combined results obtained from all 16 pairs of the experimental animals were analyzed, the results showed that on a basis of activity per gram dry matter of intestinal contents, ingested chlortetracycline was associated with significant increases in amylase and cellulase but not in protease activity. Protease, amylase, and cellulase activities per gram dry matter of cecal contents were higher for pigs fed the antibiotic than for their controls. The mean wet weight of the empty small intestine and the mean dry weight of the mucosa scraped from the anterior 3-meter section of the small intestine were lower for the chlortetracycline-fed animals, but the differences were not statistically significant.


2019 ◽  
pp. 115-119
Author(s):  
Tímea Rubóczki ◽  
Mária Takácsné Hájos

An increasing interest has been observed of beetroot leaf as a salad component due to recent studies focusing on their nutritional value. The randomized field experiment was carried out on lowland chernozem soil with 6 varieties, 3 replications and 2 sowing dates. Sampling was performed on 23 of August 2018 at the stage of 30 and 50 days of vegetation, where leaf (30 and 50 days) and root (50 days) were collected. Total dry matter, folic acid and nitrate content were evaluated. The results of this investigation show that higher total dry matter content was measured in the root (8.47–10.30%) compared to the leaf in both developmental stages (6.47–9.20%). Nevertheless, higher folic acid content was found in the young leaves of 30 and 50 days of development (58.77–113.86 µg 100g-1). Among the examined varieties, Bonel has presented great amount of folic acid not only in the leaves (99.35–113.61 µg 100g-1), but also in the root (89.99 µg 100g-1). Finally, lower nitrate content was found in Libero (316.16 mg kg-1) at 30 days and in Akela (340.41 mg kg-1) at 50 days of development. Thereby, fresh consumption of beetroot leaves are highly recommended.


Weed Science ◽  
1986 ◽  
Vol 34 (2) ◽  
pp. 271-275 ◽  
Author(s):  
George Marshall

The growth and development of field horsetail (Equisetum arvenseL. # EQUAR) was measured outdoors using potted plants grown from one-node rhizome fragments. Shoot growth rate increased slowly after planting in March, accelerating to a maximum during July with maximas for shoot height during August and shoot number in September. Rhizome system growth rates initially followed a similar pattern to that of the shoots achieving a maximum during July. Dry matter accumulated in the rhizomes until October and declined thereafter throughout the winter. Tubers initiated during August grew in size and number until November, well beyond the period of active shoot growth and onset of senescence. The characteristics of the growth and development of field horsetail are discussed in relation to achieving weed control via cultural and herbicide treatments.


Energies ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4680 ◽  
Author(s):  
Moritz von Cossel ◽  
Anja Mangold ◽  
Yasir Iqbal ◽  
Iris Lewandowski

This study reports on the effects of two rhizome-based establishment procedures ‘miscanthus under maize’ (MUM) and ‘reference’ (REF) on the methane yield per hectare (MYH) of miscanthus in a field trial in southwest Germany. The dry matter yield (DMY) of aboveground biomass was determined each year in autumn over four years (2016–2019). A biogas batch experiment and a fiber analysis were conducted using plant samples from 2016–2018. Overall, MUM outperformed REF due to a high MYH of maize in 2016 (7211 m3N CH4 ha−1). The MYH of miscanthus in MUM was significantly lower compared to REF in 2016 and 2017 due to a lower DMY. Earlier maturation of miscanthus in MUM caused higher ash and lignin contents compared with REF. However, the mean substrate-specific methane yield of miscanthus was similar across the treatments (281.2 and 276.2 lN kg−1 volatile solid−1). Non-significant differences in MYH 2018 (1624 and 1957 m3N CH4 ha−1) and in DMY 2019 (15.6 and 21.7 Mg ha−1) between MUM and REF indicate, that MUM recovered from biotic and abiotic stress during 2016. Consequently, MUM could be a promising approach to close the methane yield gap of miscanthus cultivation in the first year of establishment.


2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 155-156
Author(s):  
Roman Castañeda-Serrano ◽  
Fabian Gutierrez-Oviedo ◽  
Marcela Diaz-Cristancho ◽  
Jairo Pardo-Guzman ◽  
Paula Lozano-Morales ◽  
...  

Abstract The objective of this study was to evaluate the effects of different energy sources on performance, and carcass characteristics in hair lambs finished in feedlots. Twenty-eight hair lambs with an initial body weight (BW) 20.8 ± 3.01, were randomly assigned to one of four dietary treatments included with seven lambs per treatment. The dietary treatments included an energy source included at 18% Dry matter: S. spectabilis flour (SF), palm kernel (PK), corn bran (CB) and rice bran (RB) in a diet based in corn silage, ground corn, soybean meal formulated to 13.0% PC and 2.6 Mcal/Kg of DM. The feeding trial was performed for 13 weeks. Water was allowed ad libitum. Animals were slaughtered after the feeding trial, and the carcasses were kept at 4°C for 24 h under Colombian standard guidelines. Data were analyzed by using the ANOVA procedure, SAS version 9.1 to perform a randomized complete experiment with four diets. For each studied variable, the mean and standard error of the mean (SEM) were calculated and differences between means were evaluated Using Tukey′s Test (P ≤ 0.05). Final body weight, hot carcass weight, cold carcass weight, hot dressing carcass (%), and cold dressing weight (%) were not different between the four treatments (P &gt; 0.05). Dry matter intake was superior to the S. spectabilis flour (P &lt; 0,001). Feed efficiency was higher in the CB and RB treatments (P &lt; 0,05). These results indicate that the inclusion of S. spectabilis and palm kernel could improve the dry matter intake and corn bran and rice bran the feed efficiency without effects on carcass characteristics


1979 ◽  
Vol 42 (1) ◽  
pp. 89-96 ◽  
Author(s):  
N. F. Suttle

1. The minced carcases of twenty-seven lambs, ranging from 18 to 69 kg in live weight, and twenty-five calves (30–90 kg) were analysed for copper, iron, manganese and zinc. The lambs were weaned whereas the calves were reared exclusively on milk.2. Mean concentrations of Fe, Mn and Zn for groups of lamb carcases fell within the ranges 52.6–75.1, 0.7–1.2 and 20.8–25.6 mg/kg fresh carcase weight respectively. The concentrations of Fe and Mn decreased while that of Zn increased slightly with age at slaughter. The concentrations of Fe, Mn and Zn in calves were close to thosein lambs.3. For both species, the concentration of Cu in the carcase varied erratically: variation in hepatic Cu storage was implicated. In an additional study of ten full-term foetuses from Cu-depleted or Cu-supplemented ewes, a dietary Cu supplement (10 mg/kg dry matter (DM)) increased foetal Cu status 10-fold, due largely to an increase in foetal liver Cu.4. The mean retentions of trace elements in the lamb carcases (%intake) were approximately: Cu 2.0, Fe 1.3, Mn 0.08, Zn 4.0. The corresponding values for the milk-fed calves were all probably much higher (Cu 23, Fe 43.7, Mn 4.9, Zn 34.0) but Cu intake was not accurately measured.5. After allowing for tissue storage of Fe and Mn, values of 55, 0.85 and 24 mg/kg carcase gain were taken to represent the approximate net growth requirements of lambs for Fe, Mn and Zn respectively: the corresponding value for Cu was probably < 1.0 mg/kg. Values for calves were similar to those for lambs.6. It was concluded that the total net requirements of ruminants for Fe and Zn shouldbe considered in terms of daily intakes of the metans rather than dietary concentrationsbecause of the relatively large and constant contribution of the growth component to thetotal requirement.


1986 ◽  
Vol 55 (1) ◽  
pp. 87-98 ◽  
Author(s):  
Anna L. Rainbird ◽  
A. G. Low

1. Simple gastric cannulas were surgically fitted to four pigs, initially of 30 kg live weight, to examine the effects of guar gum on gastric emptying.2. Four semi-purified high-fat diets based on starch, casein, soya-bean oil and tallow were given to each pig. They contained 0 (control), 20, 40 or 60 g powdered guar gum/kg diet. The meals as fed contained 257 g dry matter (DM)/kg.3. The contents of the stomach were evacuated, with rinsing, before feeding or 0.5, 1, 2 or 4 h after feeding.4. The mean pH of the digesta was unaffected by guar gum until 4 h after feeding when the value increased as the amount of guar gum in the diet rose.5. The only significant effects of guar gum on the emptying of digesta and its components (compared with the control diet) were to reduce the rate of emptying of (a) digesta 1 h after feeding (60 g/kg diet) and 4 h after feeding (40 and 60 g/kg diets), (b) dry matter and glucose 1 h after feeding (60 g/kg diet), (c) nitrogen 1 h after feeding (60 g/kg diet) and 4 h after feeding (40 and 60 g/kg diets).6. When expressed on a half-time (T50) basis, the emptying of digesta and N (but not of DM and glucose) were significantly slower for diets containing 40 and 60 g guar gum/kg than for the control diet.7. The apparent viscosity of the gastric digesta ranged between 0.5 and 23.7% of the values for the diets as consumed.8. It was concluded that the effects of guar gum on gastric emptying of high-solid meals were small, and that this was unlikely to be an important aspect of the mechanism by which guar gum reduces postprandial blood glucose concentrations.


Sign in / Sign up

Export Citation Format

Share Document