The Relative Response of Two Foxtail (Setaria) Species to Diclofop

Weed Science ◽  
1984 ◽  
Vol 32 (5) ◽  
pp. 686-690 ◽  
Author(s):  
Ian N. Morrison ◽  
Denise C. Maurice
Keyword(s):  
Dry Weight ◽  
Regression Equations ◽  
Growth Reduction ◽  
Relative Growth ◽  
Leaf Stage ◽  
Relative Response ◽  
Green Foxtail ◽  
Higher Ed ◽  
Significant Difference ◽  
The Difference

ED50values (the dosage required to reduce the posttreatment gain in dry weight by 50%) for diclofop applied to green and yellow foxtail [Setaria viridis(L.) Beauv. ♯3SETVI andS. lutescens(Weigel.) Hubb. ♯ SETLU] at the two- and four-leaf stages were calculated from linear regression equations derived by plotting the logarithm of the applied dosage against the relative growth reduction expressed as a probit value. At the two-leaf stage, green foxtail was more susceptible to the chemical than yellow foxtail but at the four-leaf stage there was no significant difference in response of the two species. At least part of the difference in sensitivity of the two species at the two-leaf stage could be accounted for by differences in spray retention, with green foxtail retaining 1.8 times (expressed as μL/cm2) or 3.5 times (expressed as μL/g dry weight) as much spray as yellow foxtail, despite the fact that yellow foxtail had a greater projected leaf area. At the four-leaf stage, the amount of spray retained by both species calculated on a per gram dry-weight basis was significantly less than at the two-leaf stage, accounting in part for the higher ED50values obtained at the later growth stage. However, there appeared to be no direct relationship between the amount of spray retained and the comparative growth response of the two weeds at the later stage of application.

Comparison of Green Foxtail (Setaria viridis) and Wild Oat (Avena fatua) Growth, Development, and Competitiveness under Three Temperature Regimes

Weed Science ◽  
1993 ◽  
Vol 41 (3) ◽  
pp. 369-378 ◽  
Author(s):  
David A. Wall
Keyword(s):  
Leaf Area ◽  
Dry Weight ◽  
Mature Seed ◽  
Wild Oat ◽  
Replacement Series ◽  
Relative Growth ◽  
Temperature Regimes ◽  
Green Foxtail ◽  
Increasing Temperature ◽  
Series Study

In a replacement series study, barley was more competitive than green foxtail and wild oat at 28/22 and 22/16 C. Wild oat was more competitive with green foxtail at 22/16 C than at 28/22 C. Maximum green foxtail dry weight and leaf area was produced at 28/22 C. As temperature increased, maximum dry weight and leaf area occurred earlier during plant growth. Similarly, maximum wild oat leaf area occurred earlier with increasing temperature, but the greatest leaf area was observed at 16/10 C. Leaf area ratio (LAR) and relative growth rate (RGR) of wild oat did not differ markedly between temperature regimes. Green foxtail LAR was higher while RGR was lower at 16/10 C than at 22/16 or 28/22 C. Under the 16/10 C regime green foxtail produced little mature seed. Greatest seed numbers were produced at 28/22 C. Wild oat produced mature seed under all temperature regimes with the greatest seed numbers produced at 22/16 C.

The growth and activity of winter wheat roots in the field: the effect of sowing date and soil type on root growth of high-yielding crops

1984 ◽  
Vol 103 (1) ◽  
pp. 59-74 ◽  
Author(s):  
P. B. Barraclough ◽  
R. A. Leigh
Keyword(s):  
Winter Wheat ◽  
Root Growth ◽  
Grain Yield ◽  
Dry Weight ◽  
Sowing Date ◽  
Thermal Time ◽  
Regression Equations ◽  
Root Dry Weight ◽  
Significant Difference ◽  
Distribution Of Roots

SummaryThe effect of sowing date on root growth of high-yielding crops (8–1 It grain/ha, 85% D.M.) of winter wheat (Triticum aestivum L. cv. Hustler) was measured at Rothamsted and Woburn in 1980 and 1981. Roots were sampled by coring on five occasions and changes in root dry weight and length were determined. The average growth rate between March and June was about 1 g/m2/day (200 m/m2/day), over 5 times that measured between December and March. Increases in root weight or length with time were generally exponential to anthesis when the crops had 101–172 g root/m2 (20–32 km/m2). September-sown wheat had more root than October-sown wheat at all times, but whereas early differences in length were maintained throughout the season, root weights converged between March and June. Overall, there was no significant difference in root dry-matter production between sites at anthesis, but there was a substantial difference between years. Differences in root growth between crops were reduced by plotting the amount of root against either the number of days from sowing or accumulated thermal time. Using che latter, root growth between December and June was reasonably linear although there was some indication of a lag below 500 °C days. Regression equations obtained for the relationships between root growth and accumulated thermal time also fitted previously published data and may provide general descriptions of root growth with time.Roots of September-sown crops reached 1 m depth by December but those of October-sown crops were not detectable at this depth until April. For most crops the distribution of roots with depth was reasonably described by an exponential decay function, with over 50% of the roots in the top 20 cm of soil at all times. At Woburn in 1981, a plough-pan restricted roots to the upper soil horizons for most of the season but apparently had little effect on the total amount of root produced. For one of the experimental crops an empirical mathematical function describing the distribution of roots with depth and time is presented.Using the data from this and previously published studies, the relationship between grain yield and the amount of root at anthesis was investigated. Total root length was positively correlated with grain yield but nonetheless similarly yielding crops could have different-sized root systems. Total root dry weight was poorly correlated with grain yield.

scholarly journals Maize Genotypes With Different Zinc Efficiency in Response to Low Zinc Stress and Heterogeneous Zinc Supply

2021 ◽  
Vol 12 ◽  
Author(s):  
Jianqin Xu ◽  
Xuejie Wang ◽  
Huaqing Zhu ◽  
Futong Yu
Keyword(s):  
Functional Characterization ◽  
Dry Weight ◽  
Inbred Lines ◽  
Foraging Strategies ◽  
Zn Deficiency ◽  
Genotypic Differences ◽  
Zinc Efficiency ◽  
Significant Difference ◽  
The Difference ◽  
Zn Stress

All over the world, a common problem in the soil is the low content of available zinc (Zn), which is unevenly distributed and difficult to move. However, information on the foraging strategies of roots in response to heterogeneous Zn supply is still very limited. Few studies have analyzed the adaptability of maize inbred lines with different Zn efficiencies to different low Zn stress time lengths in maize. This study analyzed the effects of different time lengths of low Zn stress on various related traits in different inbred lines. In addition, morphological plasticity of roots and the response of Zn-related important gene iron-regulated transporter-like proteins (ZIPs) were studied via simulating the heterogeneity of Zn nutrition in the soil. In this report, when Zn deficiency stress duration was extended (from 14 to 21 days), under Zn-deficient supply (0.5 μM), Zn efficiency (ZE) based on shoot dry weight of Wu312 displayed no significant difference, and ZE for Ye478 was increased by 92.9%. Under longer-term Zn deficiency, shoot, and root dry weights of Ye478 were 6.5 and 2.1-fold higher than those of Wu312, respectively. Uneven Zn supply strongly inhibited the development of some root traits in the -Zn region. Difference in shoot dry weights between Wu312 and Ye478 was larger in T1 (1.97 times) than in T2 (1.53 times). Under heterogeneous condition of Zn supply, both the –Zn region and the +Zn region upregulated the expressions of ZmZIP3, ZmZIP4, ZmZIP5, ZmZIP7, and ZmZIP8 in the roots of two inbred lines. These results indicate that extended time length of low-Zn stress will enlarge the difference of multiple physiological traits, especially biomass, between Zn-sensitive and Zn-tolerant inbred lines. There were significant genotypic differences of root morphology in response to heterogeneous Zn supply. Compared with split-supply with +Zn/+Zn, the difference of above-ground biomass between Zn-sensitive and Zn-tolerant inbred lines under split-supply with –Zn/+Zn was higher. Under the condition of heterogeneous Zn supply, several ZmZIP genes may play important roles in tolerance to low Zn stress, which can provide a basis for further functional characterization.

THE EFFECT OF INGESTED CHLORTETRACYCLINE ON SOME HYDROLASES AND ORGANS ASSOCIATED WITH THE DIGESTIVE PROCESS IN GROWING PIGS: II. PANCREAS–DRY WEIGHT, FAT CONTENT, PROTEASE, AND AMYLASE ACTIVITY

1957 ◽  
Vol 35 (3) ◽  
pp. 187-193 ◽  
Author(s):  
M. A. A. Vonk ◽  
L. W. McElroy ◽  
J. P. Bowland ◽  
R. T. Berg
Keyword(s):  
Protease Activity ◽  
Dry Matter ◽  
Amylase Activity ◽  
Dry Weight ◽  
Feed Utilization ◽  
Fat Content ◽  
Growing Pigs ◽  
Significant Difference ◽  
Pancreatic Protease ◽  
The Difference

Results of experiments to investigate the effect of dietary chlortetracycline on pancreas dry weight and on the crude fat content and hydrolase activity of the gland are presented. Chlortetracycline fed at a level of 20 g. per ton of feed caused an increase in rate of gain and efficiency of feed utilization by pigs between the ages of 9 and 17 weeks. An effect on the pancreas was indicated by significant increases in: (a) dry weight, (b) total protease and amylase activity, and (c) amylase activity per gram dry matter of the glands from animals receiving the supplemented ration. The difference remained significant after adjustment for body weight by covariance in the case of amylase activity but not for dry weight or protease activity, indicating that the effect of chlortetracycline on amylase activity was more pronounced than that on rate of gain of pigs, pancreas dry weight, or pancreatic protease activity. No significant difference in the crude fat content of the pancreas attributable to the inclusion of chlortetracycline in the ration was observed.

Lowered pulmonary arterial pressure prevents edema after endotoxin in sheep

1987 ◽  
Vol 63 (3) ◽  
pp. 1008-1011 ◽  
Author(s):  
S. J. Allen ◽  
R. E. Drake ◽  
J. Katz ◽  
J. C. Gabel ◽  
G. A. Laine
Keyword(s):  
Pulmonary Hypertension ◽  
Arterial Pressure ◽  
Pulmonary Arterial Pressure ◽  
Venous Pressure ◽  
Dry Weight ◽  
Base Line ◽  
Capillary Membrane ◽  
Significant Difference ◽  
Pulmonary Arterial ◽  
The Difference

Escherichia coli endotoxin causes increased capillary membrane permeability and increased pulmonary arterial pressure (PAP) in sheep. If the pulmonary hypertension extends to the level of the microvasculature, then the increased microvascular pressure may contribute to the pulmonary edema caused by endotoxin. We tested the hypothesis that reducing the pulmonary hypertension would reduce the amount of edema caused by endotoxin. Twelve sheep were chronically instrumented with catheters to measure PAP, left atrial pressure, and central venous pressure. The sheep were divided into two groups. One group (E) of six sheep received an intravenous infusion of 4 micrograms/kg of E. coli endotoxin. The second group (E + SNP) received the same dose of endotoxin as well as a continuous infusion of sodium nitroprusside (SNP) to reduce PAP. Three hours after the endotoxin infusions, the sheep were terminated and the extravascular fluid-to-blood-free dry weight ratios of the lungs were determined (EVF). The base-line PAP was 17.5 +/- 2.7 mmHg. A two-way analysis of variance demonstrated a significant difference (P less than 0.01) in PAP between the E and E + SNP groups. Although PAP in each group varied as a function of time, the difference between the two groups did not. The mean PAP for the E + SNP group (20.9 +/- 1.5 mmHg) was lower than the E group PAP of 27.3 +/- 2.1 mmHg after the endotoxin spike. Furthermore, the E + SNP group EVF (3.9 +/- 0.2) was significantly less than the EVF of the E group (4.7 +/- 0.5).(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of Limited Water Supply on Photosynthetic Characteristics of Spring Maize (Zea Mays)

2013 ◽  
Vol 404 ◽  
pp. 420-424
Author(s):  
Heng Jia Zhang ◽  
Jun Hui Li
Keyword(s):  
Growth Rate ◽  
Water Supply ◽  
Grain Filling ◽  
Growth Stages ◽  
Relative Growth ◽  
Crop Growth Rate ◽  
Leaf Stage ◽  
Spring Maize ◽  
Significant Difference ◽  
Leaf Area Duration

A trial was carried out to investigate the effect of limited water supply on leaf area duration (LAD), relative growth rate (RGR), crop growth rate (CGR), and above-ground biomass (AB) of spring maize. The results indicated that the LAD was significantly (p<0.05) increased by 10.6%, 15.4%, 16.9%, 19.3%, 13.4% and 17.0%,12.2%, 19.7%, 18.4%, 20.9% in MI1, MI3, MI4, MI5, CK than MI2 during both 12-leaf stage to heading and heading to silking. There was no significant difference (p>0.05) in RGR among all the treatments and check during 6-leaf to 12-leaf stage and silking to middle grain filling, but significant difference occurred during other measured stages. Also, significant difference was found in CGR among some treatments and check during all the measured growth stages. The maximum AB of maize was maintained in CK with 23.0 t ha-1, significantly improved by 16.2%, 16.2%, 22.3% and 41.1%, 35.3% respectively than in MI1, MI4, MI5 and MI2, MI3, and the minimum AB was recorded in MI2 with 16.3 t ha-1.

COMPARISON OF PHOTOSYNTHESIS IN NORMAL AND TRIAZINE-RESISTANT Brassica

1987 ◽  
Vol 67 (2) ◽  
pp. 457-466 ◽  
Author(s):  
S. L. A. HOBBS
Keyword(s):  
Carbon Dioxide ◽  
Exchange Rate ◽  
Chlorophyll A ◽  
Dry Weight ◽  
Stomatal Resistance ◽  
Carbon Dioxide Exchange ◽  
Shoot Dry Weight ◽  
Significant Difference ◽  
The Difference ◽  
Net Assimilation

In spaced field plantings, triazine-resistant types of Brassica campestris L. and B. napus L. had a carbon dioxide exchange rate (CER) 28% lower in 1983 and 25% lower in 1984 than normal (triazine-susceptible) types. In plots simulating agronomic spacings in 1984, the difference between CER in normal and resistant types was 17% for B. campestris, 14% for B. napus and 13% for B. juncea L. Differences were apparent throughout the season and were not associated with any particular stage of growth. Resistant progeny from reciprocal crosses between resistant and susceptible plants of B. napus exhibited reduced CER at all levels of photosynthetically active radiation and at all temperatures. There was no significant difference between plant types for chlorophyll a + b content or chlorophyll a/b ratio. Shoot dry weight, stomatal resistance and specific leaf weight were higher in the normal types, but there was no difference between types in either relative growth rate or net assimilation rate. The reduced biomass was not therefore linked to reduced CER.Key words: Carbon dioxide exchange rate, herbicide, oilseed, rapeseed

scholarly journals Ammonium/nitrate ratio affects the growth and glucosinolates content of pakchoi

2020 ◽  
Vol 38 (3) ◽  
pp. 246-253
Author(s):  
Jing Yang ◽  
Biao Zhu ◽  
Xiaolei Ni ◽  
Yong He
Keyword(s):  
Plant Growth ◽  
Ammonium Nitrate ◽  
Dry Weight ◽  
Hydroponic System ◽  
N Supply ◽  
Significant Difference ◽  
The Difference ◽  
Ammonium Level ◽  
The Individual ◽  
Β Carotene

ABSTRACT Nitrogen (N) strongly affects plant growth. However, little is known about the effects of the ammonium/nitrate ratio on pakchoi (Brassica rapa), especially its glucosinolates (GSs) contents which are involved in plant defense and many of them benefit to human health. The aim of this study was to evaluate the effects of a constant N supply (8 mM) but with five ammonium/nitrate ratios (namely 0/8 mM, 2/6 mM, 4/4 mM, 6/2 mM and 8/0 mM) on the growth of pakchoi in a hydroponic system in 2 years. In both years, a higher biomass (dry weight) was in the 4/4 and 2/6 ammonium/nitrate treatments (2.3 and 2.2-fold compared to 8/0, respectively), with no significant difference in biomass between these two treatments. The biomass then decreased with increasing proportions of ammonium in the N supply from more than 10 g/pot to below 5 g/pot. The N and sulfur contents were strongly affected in the sole nitrate or ammonium treatments, as were the contents of chlorophyll, lutein, and β-carotene. Most of the individual glucosinolates (GSs) detected in pakchoi showed the highest concentrations in the sole ammonium treatment. The ammonium/nitrate ratio also affected the types of GSs. The highest proportion of indolyl GSs and the lowest proportion of aromatic GSs were in the sole ammonium treatment. We concluded that a high ammonium level decreases the biomass but increases the GSs concentrations in pakchoi. Further studies are required to explore the difference in GSs metabolism among plants supplied with different ammonium/nitrate ratios.

The pattern of flowering, seed set, seed growth and ripening along the ear of Lolium perenne

1998 ◽  
Vol 25 (2) ◽  
pp. 213 ◽  
Author(s):  
J.W. Warringa ◽  
P.C. Struik ◽  
R. de Visser ◽  
A.D.H. Kreuzer
Keyword(s):  
Growth Rate ◽  
Lolium Perenne ◽  
Seed Set ◽  
Dry Weight ◽  
Spatial And Temporal Patterns ◽  
Relative Growth ◽  
Lolium Perenne L ◽  
Seed Growth ◽  
The Difference ◽  
Main Factor

A greenhouse pot experiment was conducted to elucidate the pattern of decreasing seed set and seed dry weight found from the basal to the upper spikelet in Lolium perenne L. ears and—very markedly—acropetally within a spikelet. The changes in fresh and dry weight of the seed after anthesis were monitored for 12 positions within the ear. To determine the duration of seed growth, the spatial and temporal patterns of flowering and ripening along the ear were assessed. The proximal florets of the central spikelets flowered first, and the upper spikelets in the ear flowered before the basal spikelets, with flowering proceeding acropetally within a spikelet. The upper spikelets ripened earlier than the basal ones, and the seeds within a spikelet ripened simultaneously. These patterns of flowering and ripening along the ear resulted in different durations of seed growth along the ear. Thus from the proximal to the distal seed within a spikelet the duration of growth decreased by 26%, the rate of growth fell by 48% and seed set and seed dry weight also fell sharply. Of the total variation in maximum, final seed dry weight within the ear, 4% could be attributed to the difference in seed dry weight between spikelets and 89% to differences in seed dry weight within spikelets. Differences in duration and rate of seed growth and seed set were also much smaller between spikelets than within spikelets. About 60% of the differences in seed dry weight along the ear were attributable to differences in growth rate and about 30% to differences in the duration of seed growth. The relative growth rate did not differ between seeds in different positions. The main factor determining seed growth rate was the dry weight of the ovule at anthesis, which declined sharply from the proximal to the distal floret within a spikelet. Analysis of the fructose, glucose, sucrose and starch concentrations showed that seed growth was not limited by the availability of sucrose nor by the ability of the seeds to convert sucrose into starch. These conclusions were supported by results from a second greenhouse experiment in which all ovules in 50% of the spikelets were removed at anthesis. Dry weight of the remaining seeds increased by only 15%.

Development of equations for estimating yield losses caused by multi-species weed communities dominated by green foxtail [Setaria viridis (L.) Beauv.]

1993 ◽  
Vol 73 (2) ◽  
pp. 625-635 ◽  
Author(s):  
L. Hume
Keyword(s):  
Multiple Regression ◽  
Spring Wheat ◽  
Dry Weight ◽  
Crop Loss ◽  
Regression Equations ◽  
Setaria Viridis ◽  
Important Species ◽  
Weed Communities ◽  
Green Foxtail ◽  
Crop Density

Multiple regression equations were developed to describe the relationship between percentage hard red spring wheat (Triticum aestivum L.) loss and the density and shoot dry weight of multi-species weed communities dominated by green foxtail [Setaria viridis (L.) Beauv.]. Data were collected over a 10-yr period from fields sown by farmers near Regina, Saskatchewan. Weed densities averaged 470 plants m−2, with green foxtail constituting 85% of the total number of plants and 57% by dry weight. Other important species included in the equations were stinkweed (Thlaspi arvense L.), common lamb’s-quarters (Chenopodium album L.), wild buckwheat (Polygonum convolvulus L.), and wild mustard (Sinapis arvensis L.). Including crop density as a variable made a significant improvement in the efficiency of the equations. Precipitation and growing degree-days (base 5 °C) were related to the residuals from the analysis relating wheat loss to weed abundance. These environmental variables were significantly related to crop loss, but only for the residuals of the equation where weed densities were used as independent variables. Hyperbolic and sigmoidal equations were less efficient at describing the data than were multiple linear regression equations. Key words: Green foxtail, spring wheat, competition, multi-species, multiple regression, crop loss

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