CHANGES IN THE LIPID AND NITROGEN CONTENT DURING POSTEMBRYONIC DEVELOPMENT OF PSEUDALETIA UNIPUNCTA (LEPIDOPTER A: NOCTUIDAE)

1973 ◽  
Vol 105 (3) ◽  
pp. 471-478
Author(s):  
M. K. Mukerji ◽  
J. C. Guppy

AbstractChanges were recorded in dry matter content and in the metabolism of lipids and nitrogen during the postembryonic development of Pseudaletia unipuncta (Haw.) on corn. The study revealed that 22 to 24% of the lipids were used during moulting and pupal–adult transformation and that nitrogen was not lost during such periods. The coefficient of apparent utilization of nitrogen remained more or less constant; however, that of lipids decreased with larval development. No significant difference was evident in the relationship between lipid consumption and weight gain, and nitrogen consumption and weight gain during larval development. A direct linear relationship was obtained between nitrogen and lipid utilization during all instars. In terms of heterauxesis, the accumulation of lipids during larval development was opposed to that of nitrogen.

Forests ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 692
Author(s):  
Johanna Riikonen ◽  
Jaana Luoranen

Determination of safe times at which to transfer seedlings to freezer storage is problematic in forest tree nurseries. The present study aimed to determine the relationship between pre-storage frost hardiness (FH) of different plant parts, dry matter content (DMC), chilling hours (the sum of hours when temperature was between −5 °C and +5 °C), and post-storage vitality, and the impact of short-day (SD) treatment on these relationships. One and a half year old control seedlings and SD-treated seedlings of Norway spruce were transferred to freezer storage (−3 °C) on five occasions during autumn. On each occasion, the FH of buds, needles, stem, and roots, as well as DMC, were determined, and chilling hours were calculated. The vitality of the freezer-stored seedlings was determined through their root growth capacity in the subsequent spring, and through the field performance of the seedlings (shoot growth and seedling damage) at the end of the following two growing seasons. Seedlings were considered to be storable when the FH of the needles was at least −25 °C, and the FH of the roots was about −10 °C in both treatments. Early storage reduced the vitality of the seedlings. SD treatment did not advance the storability of the seedlings, although it alleviated some of the negative effects of early storage by improving the FH of needles and stem, but not that of the roots. The DMC value, indicating storability, was higher for SD-treated seedlings than for control seedlings. When data from five experiments conducted in Suonenjoki were combined, it was found that the relationship between accumulation of chilling hours and needle FH was dependent on nursery treatment and assessment year, which reduces the reliability of using chilling hours in predicting the storability of Norway spruce seedlings. The predicted climate change may complicate the fall acclimation of seedlings. New, user-friendly methods for determining storability of seedlings are urgently needed.


2000 ◽  
Vol 43 (4) ◽  
pp. 361-364
Author(s):  
Gilad Ashbell ◽  
Evert Evers ◽  
Ate H. Bosma

The correlation between dry matter (DM) content, electrical conductivity (EC) and ash content was found to be linear in grass and alfalfa during drying. While minerals in grass and alfalfa were very stable components during drying, their concentrations and EC increase accordingly; therefore, the EC value could serve as a measurement to determine DM content. Results indicated that EC measurement in grass and alfalfa during drying was simple, accurate, fast and easily repeatable, and could serve as an alternative method for DM determination.


1975 ◽  
Vol 84 (2) ◽  
pp. 365-372 ◽  
Author(s):  
C. Thomas ◽  
R. F. Wilson ◽  
R. J. Wilkins ◽  
J. M. Wilkinson

SUMMARYMaize was cut at 22·6, 27·0 and 41·6% dry matter and ensiled in 4 kg quantities in polythene bags without additive or after the addition of urea at 0·5, 1·0, 1·5 and 2·0% of the crop dry-matter content. Silos were opened at intervals up to 96 days. Maize of 23·4% dry-matter content was ensiled in 10 t butyl rubber silos without additive or after the addition of urea at 1·0% or fishmeal at 4·0% of the crop dry-matter content.Silages from the polythene bag silos were all well preserved. pH values increased and total acid content fell with increasing maturity of the crop. Addition of urea had little effect on these values. Only with the most mature crop did ammonia content increase markedly with increasing level of urea addition. All silages from the butyl rubber silos were well preserved with low pH values and similar total acid contents.Silages from the butyl rubber silos were used to measure voluntary, intake live-weight gain and efficiency of utilization of young beef cattle. The diets fed were silage without nitrogen supplement or supplemented with urea or fishmeal, added at ensiling, at feeding or included in a concentrate feed. One third of the total dry-matter intake of all cattle was provided by a pelleted concentrate feed consisting of equal quantities of dried grass and rolled barley.The increase in nitrogen content brought about by the addition of urea or fishmeal did not affect total dry-matter or organic-matter intake but was associated with 25% increase in nitrogen consumed. Live-weight gain on all treatments with added nitrogen was 20% higher than for the unsupplemented silage. This improvement in growth rate was accompanied by significant increases in efficiency of utilization of dietary dry matter and organic matter but efficiency of nitrogen utilization was reduced. The results indicate that neither the source nor site of addition of supplementary nitrogen significantly affect live-weight gain, dry-matter intake, organic-matter intake or utilization of dry matter or organic matter. They also demonstrate that urea can be used effectively to provide supplementary nitrogen to young cattle fed a maize silage-based ration.


1983 ◽  
Vol 63 (3) ◽  
pp. 601-609 ◽  
Author(s):  
M. R. VATTIKONDA ◽  
R. B. HUNTER

A 2-yr study was conducted at Elora and Brucefield, Ont. to examine the relationship between grain yield following grain physiological maturity and whole-plant dry matter (DM) yield and quality determined at the stage desirable for ensiling. Quality parameters analyzed include in vitro dry matter digestibility (IVD) of the stover, IVD of the whole plant, stover lignin content and stover protein content. There was a significant linear relationship between the performance of hybrids for grain yield production and their yield for silage production. However, the relationship was not complete enough to permit reliable selection of hybrids for silage production based on grain yield performance (coefficients of determination were 0.23 and 0.25 for Elora and Brucefield, respectively). Grain dry matter content, however, provided a satisfactory estimate of whole-plant maturity for silage production. Coefficients of determination between grain DM content and whole-plant DM content were 0.71 and 0.53 for Elora and Brucefield, respectively. There was considerable variation among hybrids for lignin content and IVD of stover. Differences were much less for whole-plant IVD. The findings of this study support the need for separate evaluation trials for corn grown for whole-plant silage production as opposed to grain production.Key words: Zea mays, corn silage, grain yield, hybrid performance


1986 ◽  
Vol 107 (3) ◽  
pp. 723-733 ◽  
Author(s):  
S. J. Wilcockson

Two experiments are reported which investigated the effects of time and method of crop defoliation and of extending the interval between defoliation and harvest on the relationship between dry-matter percentage and tuber size in Pentland Crown potatoes.Differences in average tuber dry-matter content between seasons and treatments were large, but the relationship between tuber dry-matter percentage and tuber size was always negatively quadratic. The dry-matter content of tubers of all sizes invariably decreased after defoliation, by about 0·6 % on average for each week that harvest was delayed in 1983 and 0·3 % in 1984. The largest decrease was from 22·7 to 16·7 % over the 10-week period following mechanical defoliation in mid-August 1983. In 1984, chemical defoliation in mid-August gave a smaller decrease than the mechanical method (0·25 and 0·38%/week) but their effects were similar when carried out in mid-September. Water uptake was the main factor responsible for the decrease because evidence showed that fresh weights of tubers increased proportionally following defoliation whilst dry weights remained virtually constant.Natural senescence was late in both seasons experiments so that the crops foliage was still mostly alive when defoliation occurred, even in September and early October. Thus, the relatively large effects of late defoliation may have been greater than might be expected where haulm senescence is already well advanced by this time and water uptake has almost ceased. Nevertheless, the decline in dry-matter percentage which may occur between defoliation and harvest can be extremely important where potatoes for processing are concerned. It could make them unacceptable for particular outlets and should be considered when defoliation and harvesting programmes are planned.


2020 ◽  
pp. 31
Author(s):  
M. P. Martín ◽  
J. Pacheco-Labrador ◽  
R. González-Cascón ◽  
G. Moreno ◽  
M. Migliavacca ◽  
...  

<p>Mixed vegetation systems such as wood pastures and shrubby pastures are vital for extensive and sustainable livestock production as well as for the conservation of biodiversity and provision of ecosystem services, and are mostly located in areas that are expected to be more strongly affected by climate change. However, the structural characteristics, phenology, and the optical properties of the vegetation in these mixed -ecosystems such as savanna-like ecosystems in the Iberian Peninsula which combines herbaceous and/or shrubby understory with a low density tree cover, constitute a serious challenge for the remote sensing studies. This work combines physical and empirical methods to improve the estimation of essential vegetation variables: leaf area index (<em>LAI</em>, m<sup>2</sup> / m<sup>2</sup> ), leaf (C<sub>ab,leaf</sub>, μg / cm<sup>2</sup> ) and canopy(C<sub>ab,canopy</sub>, g / m<sup>2 </sup>) chlorophyll content, and leaf (C<sub>m, leaf</sub>, g / cm<sup>2</sup> ) and canopy (C<sub>m,canopy</sub>, g / m<sup>2</sup> ) dry matter content in a dehesa ecosystem. For this purpose, a spectral simulated database for the four main phenological stages of the highly dynamic herbaceous layer (summer senescence, autumn regrowth, greenness peak and beginning of senescence), was built by coupling PROSAIL and FLIGHT radiative transfer models. This database was used to calibrate different predictive models based on vegetation indices (VI) proposed in the literature which combine different spectral bands; as well as Partial Least Squares Regression (PLSR) using all bands in the simulated spectral range (400-2500 nm). PLSR models offered greater predictive power (<em>R<sup>2</sup></em> ≥ 0.93, <em>RRMSE</em> ≤ 10.77 %) both for the leaf and canopy- level variables. The results suggest that directional and geometric effects control the relationships between simulated reflectance factors and the foliar parameters. High seasonal variability is observed in the relationship between biophysical variables and IVs, especially for <em>LAI</em> and <em>C<sub>ab</sub></em>, which is confirmed in the PLSR analysis. The models developed need to be validated with spectral data obtained either with proximal or remote sensors.</p>


Rangifer ◽  
1996 ◽  
Vol 16 (1) ◽  
pp. 21 ◽  
Author(s):  
Anna Nilsson ◽  
Ingemar Olsson ◽  
Per Lingvall

A study was made of whether the dry matter content of silage influenced performance when 17-month-old male reindeer were fed solely silage outdoor during winter. Two kinds of round-baled silages with different wilting times were offered to the animals; low dry matter (LDM silage) with a mean of 39% DM, or high dry matter (HDM silage) with a mean of 53% DM. The 115 reindeer were allotted to slaughter at the start of the experiment in October or to be fed until slaughter in January or March. During the first three weeks of the experiment small amounts of lichens were mixed with the silages and the reindeer adapted to the feeding without problems. The daily intake of DM did not differ significantly between reindeer fed the LDM or the HDM silage despite a highly significant difference in daily silage intake. This resulted in small but significantly higher gains in live weight for animals fed the LDM silage, caused by increased weight of the rumen content. All groups of reindeer either retained or lost carcass weight during the experiment, and no improvements or differences were obtained between the kinds of silages in carcass assessment or gains in fat in the abdominal cavity. Animals slaughtered in January had a lower carcass weight and dressing percentage than reindeer slaughtered in October and March. Environmental conditions during the experiment were good but nonetheless mobbing and illness still occurred. The present results concur with those of earlier studies suggesting that it seems to be the bulk of the ration rather than the dry matter content of the silage that limits the intake.


2019 ◽  
Vol 2019 ◽  
pp. 1-16 ◽  
Author(s):  
Loreto Atieno ◽  
Willis Owino ◽  
Elijah M. Ateka ◽  
Jane Ambuko

Various modes of edible coating application vary in their coat dispersion and film formation, hence the need to determine the most effective mode of application for cassava. Edible surface coatings have been found to be effective in preserving the quality of various food products. However, there are variations in effectiveness among the different coating solutions, hence the need for optimization of the concentrations of the gums used. This study aimed at determining the most efficient coating application method on the cassava postharvest quality. Physiologically mature cassava (variety KME 1) was harvested and divided into seven portions. The various portions were coated using 1.5% xanthan gum, 1.5% xanthan/guar gum, and 2% xanthan/guar gum by both dipping and spraying method. There was no significant difference on the colour, total cyanide, ethylene production, and total phenolic content between the two application methods. The 2% xanthan/guar gum coating showed a significant difference on the dry matter content while the 1.5% xanthan gum coating had a significant difference on the respiration rate and weight loss. The 1.5 xanthan treated roots had a final dry matter content of 72.5% for the sprayed samples and 75.98% for the dipped sample while the 2% xanthan/guar gum treated roots had a final dry matter content of 64.6% and 74.1% for the dipped and sprayed root samples, respectively. The 1.5% xanthan and 2% xanthan/guar gum treated roots showed no significant difference in their action on dry matter content. The 1.5% xanthan/guar dipped and sprayed samples differed significantly on their effect on flesh firmness with final values of 35.4N and 46.1N, respectively, at 20 days after harvest. This study suggested that based on the coating solution and the parameters being observed, there generally was no varying effect of dipping and spraying methods of coating application. The choice of the efficient mode of application to use will depend on other factors such as the easiness of application.


2018 ◽  
Vol 40 (2) ◽  
Author(s):  
Marcelo José Vieira ◽  
Luiz Carlos Argenta ◽  
James Peter Mattheis ◽  
Cassandro Vidal Talamini do Amarante ◽  
Cristiano André Steffens

Abstract Two experiments were carried out to evaluate the relationship between dry matter content (DMC) and maturity index of ‘Fuji’ apple fruit sports (‘Mishima’, ‘Fuji Select’ and ‘Fuji Suprema’) during the final stage of fruit growth, and the relationship between DMC at harvest and the post-harvest fruit quality. Fruit were harvested from orchards of three regions (Caçador, São Joaquim and Vacaria), on two rootstocks (M9 and Marubakaido with M9 interstock). In experiment 1 (2014), fruit were periodically sampled beginning 83 days before the commercial harvest period. In experiment 2, fruit were harvested at optimum maturity for long-term storage and stored in air at 0.5 ºC (2014) or after optimum maturity for long-term storage and stored in controlled atmosphere at 0.7 ºC (2014 and 2015). Apple fruit maturity on the tree was characterized by decreased flesh firmness and increased starch index and soluble solids content (SS) and by a small change in DMC. DMC at harvest was correlated with flesh firmness and SS in one of two years, but DMC was not correlated with the incidence of disorders after storage. The results show that DMC at harvest is not suitable as a maturity index of ‘Fuji’ apples, and its use as a post-harvest quality predictor is not consistent between crop years.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Jui-Fen Cheng ◽  
Xuan-Yi Huang ◽  
Te-Le Liu ◽  
Ruey-Yun Wang ◽  
Han-Yi Ching

Objective. To explore the relationship between body constitution (BC) types and weight change in patients with schizophrenia and who underwent second-generation antipsychotics (SGAs) treatment.Method. Body weight and waist circumference of eighty-five participants were measured for 6 consecutive weeks. Constitutions of Yin-Xu, Yang-Xu, and Stasis were assessed using the Body Constitution Questionnaire (BCQ).Results. Participants with body constitutions Yin-Xu (50.6%), Yang-Xu (49.4%), or Stasis (38.8%) exhibited worse physical condition and unhealthy daily habits, particularly in Stasis constitution. Moreover, Stasis constitution was significantly associated with several factors, including BMI, body weight, waist circumference, perception of stress, perception of health, staying up late, and less physical exercise. However, perception of stress showed significant difference in Yin-Xu, Yang-Xu, and Stasis. Generalized estimating equation (GEE) analysis revealed that significant time effects in body weight increase in the imbalanced BC types and gentleness BC type. SGAs induced weight gain in imbalanced BC type as well as gentleness BC type, especially treated with olanzapine.Conclusions. This is the first study to explore the longitudinal relationship between BC and weight gain in schizophrenia patients undergoing SGAs treatment. Health care providers should focus on weight gain problems in schizophrenia patients who underwent SGAs treatment.


Sign in / Sign up

Export Citation Format

Share Document