Journal of Agricultural Science
SCOPUS (1905-2025)SCIE-ISI
0021-8596
1469-5146
Anh Quốc
Cơ quản chủ quản: CAMBRIDGE UNIV PRESS , Cambridge University Press
Lĩnh vực:
Animal Science and ZoologyAgronomy and Crop ScienceGenetics
Phân tích ảnh hưởng
Các bài báo tiêu biểu
The estimation of protein degradability in the rumen from incubation measurements weighted according to rate of passage
Tập 92 Số 2 - Trang 499-503 - 1979
SummaryA method is proposed for estimating the percentage of dietary protein
that is degraded by microbial action in the rumen when protein supplement is
added to a specified ration. The potential degradability, p, is measured by
incubating the supplement in artificial-fibre bags in the rumen and is related
to incubation time, t, by the equation p = a+b(1 – e-ct). The rate constant k,
measuring th...
Crop losses to pests
Tập 144 Số 1 - Trang 31-43 - 2006
Productivity of crops grown for human consumption is at risk due to the
incidence of pests, especially weeds, pathogens and animal pests. Crop losses
due to these harmful organisms can be substantial and may be prevented, or
reduced, by crop protection measures. An overview is given on different types of
crop losses as well as on various methods of pest control developed during the
last century.Es...
The determination of chromic oxide in faeces samples by atomic absorption spectrophotometry
Tập 59 Số 3 - Trang 381-385 - 1962
A rapid and accurate atomic absorption method for the determination of chromium
in faeces samples from pasture experiments using chromic oxide ‘markers’ is
described. Of the elements present after ashing and digesting the samples in a
phosphoric acid—manganese sulphate—potassium bromate solution silicate,
aluminium, calcium and magnesium were found to interfere in the determination.
The effects of...
The estimation of the digestibility and metabolizable energy content of ruminant feedingstuffs from the gas production when they are incubated with rumen liquor in vitro
Tập 93 Số 1 - Trang 217-222 - 1979
SUMMARYA rapid method for measuring gas production during incubation of
feedingstuffs with rumen liquor in vitro is described. Gas production in 24 h
from 200 mg feed dry matter was well correlated with digestibility of organic
matter, determined in vivo with sheep. Multiple regression analysis, when it
included data from proximate analysis, resulted in an equation (R = 0·98) for
prediction of met...
Determination of nitrogen in soil by the Kjeldahl method
Tập 55 Số 1 - Trang 11-33 - 1960
1. The reliability of the Kjeldahl method for the determination of nitrogen in
soils has been investigated using a range of soils containing from 0·03 to 2·7%
nitrogen.2. The same result was obtained when soil was analysed by a variety of
Kjeldahl procedures which included methods known to recover various forms of
nitrogen not determined by Kjeldahl procedures commonly employed for soil
analysis. ...
Number of kernels in wheat crops and the influence of solar radiation and temperature
Tập 105 Số 2 - Trang 447-461 - 1985
SUMMARYThe number of kernels per m2 (K) in well managed and watered wheat crops
was studied using results of experiments in Mexico and Australia in which short
spring wheat cultivars were subjected to independent variation in radiation,
largely via artificial shading, and in temperature. Also crops subjected to
differences in weather (year), sowing date and location within Mexico, revealed
respons...
A revised model for the estimation of protein degradability in the rumen
Tập 96 Số 1 - Trang 251-252 - 1981
Estimates of the degradability of protein in the rumen are essential for the
application of new systems which have been suggested for the evaluation of the
protein requirements of ruminants (Agricultural Research Council, 1980). The
effective percentage degradability (P) of protein supplements in the rumen is
dependent not only on the course of degradation of the protein particles in the
rumen, bu...
Perception of and adaptation to climate change by farmers in the Nile basin of Ethiopia
Tập 149 Số 1 - Trang 23-31 - 2011
SUMMARYThe present study employed the Heckman sample selection model to analyse
the two- step process of adaptation to climate change, which initially requires
farmers' perception that climate is changing prior to responding to changes
through adaptation. Farmers' perception of climate change was significantly
related to the age of the head of the household, wealth, knowledge of climate
change, so...
The analysis of crop cultivar breeding and evaluation trials: an overview of current mixed model approaches
Tập 143 Số 6 - Trang 449-462 - 2005
The analysis of series of crop variety trials has a long history with the
earliest approaches being based on ANOVA methods. Kempton (1984) discussed the
inadequacies of this approach, summarized the alternatives available at that
time and noted that all of these approaches could be classified as
multiplicative models. Recently, mixed model approaches have become popular for
the analysis of series ...
Radiation absorption, growth and yield of cereals
Tập 91 Số 1 - Trang 47-60 - 1978
SummaryAnalysis of measurements of absorbed radiation and leaf area indices of
wheat and barley crops showed that throughout most of growth the fraction of
absorbed solar radiation could be described by a simple exponential equation.For
several of these crops grown under a wide range of weather and husbandry at
Sutton Bonington and Rothamsted, 2-weekly values of crop growth rate (C) were
closely r...