The relationship of several plant characters with grain yield in sorghum and their use in estimating grain loss through pest activity

1976 ◽  
Vol 16 (78) ◽  
pp. 129
Author(s):  
PN Vance

The relationship between grain yield and five plant characters in grain sorghum hybrid Pioneer 846 was studied. Grain yield was closely correlated with head weight, weight of a standard length of peduncle (WSP), peduncle perimeter (PP), head length and breadth. The close correlation of grain yield on WSP was shown to exist at a number of sites and for a number of varieties. However, regression equations differed for different sites, sowing dates and varieties. Of the two components of grain yield per head, single grain weight and grain number; only grain number was closely correlated with WSP. In one instance where moisture stress affected grain development, grain number but not yield was closely correlated with WSP. WSP was shown not to be affected by damage to the head and could therefore be used to estimate potential yield in agronomic trials where yield loss due to pest activity has occurred.

2018 ◽  
Vol 64 (No. 7) ◽  
pp. 310-316 ◽  
Author(s):  
Mirosavljevic Milan ◽  
Momcolovic Vojislava ◽  
Maksimovic Ivana ◽  
Putnik-Delic Marina ◽  
Pržulj Novo ◽  
...  

The aim of this study was to improve understanding of (1) the effect of genotypic and environmental factors on pre-anthesis development and leaf appearance traits of barley and wheat; (2) the relationship of these factors with grain yield, and (3) the differences between these two crops across different environments/sowing dates. Therefore, trials with six two-row winter barley and six winter wheat cultivars were carried out in two successive growing seasons on four sowing dates. Our study showed that the observed traits varied between species, cultivars and sowing dates. In both growing seasons, biomass at anthesis and grain yield declined almost linearly by delaying the sowing date. There was no clear advantage in grain yield of wheat over barley under conditions of later sowing dates. Generally, barley produced more leaf and had shorter phyllochron than wheat. Both wheat and barley showed a similar relationship between grain yield and different pre-anthesis traits.


Author(s):  
J Latchford ◽  
E C Chirwa ◽  
T Chen ◽  
M Mao

Car-rear-impact-induced cervical spine injuries present a serious burden on society and, in response, seats offering enhanced protection have been introduced. Seats are evaluated for neck protection performance but only at one specific backrest angle, whereas in the real world this varies greatly owing to the variation in occupant physique. Changing the backrest angle modifies the seat geometry and thereby the nature of its interaction with the occupant. Low-velocity rear-impact tests on a BioRID II anthropomorphic test dummy (ATD) have shown that changes in backrest angle have a significant proportionate effect on dummy kinematics. A close correlation was found between changes in backrest angle and the responses of neck injury predictors such as lower neck loading and lower neck shear but not for the neck injury criterion NICmax. Torso ramping was evident, however, with negligible effect in low-velocity impacts. The backrest angle ranged from 20° to 30° whereas the BioRID II spine was adapted to a range from 20° to 26.5°. Nevertheless, in general, instrumentation outputs correlated well, indicating that this ATD could be used for evaluating seats over a 20–30° range rather than solely at 25° as required by current approval test specifications.


2011 ◽  
Vol 48 (No. 5) ◽  
pp. 230-235
Author(s):  
M. Sabo ◽  
M. Bede ◽  
Ž.U. Hardi

Variability of grain yield components of some new winter wheat genotypes (e.g. Lara, Lenta, Kruna, Fiesta, Perla, and one line of AG-45) was examined. The analysis of grain yield components of these genotypes and the line was undertaken in a two-year research (1997/1998 and 1998/1999) at two different locations. Significant differences among genotypes, locations and research years were established. In the first experimental year (1997/1998) there was a high positive correlation between nearly all components of the grain yield. The most significant correlation was found between the grain number per spike and grain yield. In the second experimental year (1998/1999) the components did not show statistically significant correlation with the grain yield. It seems that the grain yield of examined genotypes depended significantly on the grain number per spike, grain mass per spike, and agroecological conditions during the vegetation period, whereby the potential yield was determined by the interaction among genotypes, location and production year. The biggest differences among examined genotypes of winter wheat were found in the stem height and spike length.


1956 ◽  
Vol 7 (6) ◽  
pp. 516 ◽  
Author(s):  
GC Wade

It is shown that under Tasmanian conditions there is a negative relation between the potassium status of apricot trees and their susceptibility to brown rot. From regression equations calculated, it is suggested that trees with a potassium content of about 4.6 per cent. in oven-dry leaves would be resistant to brown rot. Difficulty was experienced in increasing the potassium content of the trees by soil or spray applications of potassium fertilizer, but when this was achieved, some reduction in brown rot incidence occurred. Regular annual soil dressings of potassium chloride at the rate of 2 lb per tree was the most satisfactory treatment tested.


1946 ◽  
Vol 133 (872) ◽  
pp. 235-248 ◽  

Since a review of the conditions under which siderocytes appear will support a hypothesis that it is an ageing erythrocyte at least as strongly as Grüneberg’s (1941 a ) theory that it should be considered as a young cell, a search was made in blood films of stored mammalian blood and large numbers of siderocytes were found. The conditions affecting the rate of appearance of the siderocytes were studied, and it was found that adverse conditions would hasten their appearance. The relationship of the siderotic material to the 'easily split’ blood iron was also considered, and it seems probable that both are derived from a special and identical fraction of ‘haemoglobin’, and that this phenomenon is related to an intracorpuscular bile pigment formation. The occurrence of siderocytosis after the ingestion of acetyl phenylhydrazine by a ‘normal’ human being was followed, and a close correlation between siderocytosis, erythrocyte destruction and urinary siderosis as described by Peyton Rous (1918) is shown. The siderocyte extrudes its siderotic granules and reverts to a state at present morphologically indistinguishable from the normal erythrocyte, but appears to be susceptible of phagocytosis at this stage. The application of siderocyte counts to clinical medicine is suggested.


1994 ◽  
Vol 19 (1) ◽  
pp. 49-59 ◽  
Author(s):  
Yagesh Bhambhani ◽  
Stephen Norris ◽  
Gordon Bell

This study examined the relationship of oxygen pulse (O2 pulse) to stroke volume (SV) and arterio-venous oxygen difference [[Formula: see text] diff] during submaximal cycle exercise in untrained (UG) and trained (TG) males. Fourteen volunteers in each group completed an incremental [Formula: see text] max test and a submaximal test at 60% [Formula: see text] max to determine cardiac output (Q) via CO2 rebreathing. [Formula: see text], Q, and heart rate (HR) were used to calculate SV and [Formula: see text] diff. There were no significant differences (p >.05) between the two groups for O2 pulse, SV, and [Formula: see text] diff during submaximal exercise. Stroke volume index (SVI) was significantly higher (p <.05) in the TG. O2 pulse was significantly related to SV and SVI (p <.05) but not to [Formula: see text] diff in both groups. Regression equations for predicting SV from O2 pulse for UG and TG were Y = 6.81X + 26.7, SE = 21.4, r = 0.84, and Y = 10.33X - 32.3, SE = 14.2, r = 0.71, respectively. These results suggest that O2 pulse can be used to predict SV during submaximal cycle exercise in untrained and trained men. Key words: cardiac performance, exercise, training status


2012 ◽  
Vol 45 (3) ◽  
pp. 25-39 ◽  
Author(s):  
S. Mohammadi ◽  
M. Janmohammadi ◽  
A. Javanmard ◽  
N. Sabaghnia ◽  
M. Rezaie ◽  
...  

Abstract The capability of a genotype to achieve acceptable yield over a broad range of sub-optimum and suitable conditions is extremely imperative. Late planting and end-season drought stress are two main factors limiting wheat yield in northwest of Iran. In a 2-year field experiment at Miandoab, Iran, the ability of several selection indices to identify drought resistant genotypes under different sowing dates and moisture conditions were evaluated. Six genotypes of differing response to water scarcity were planted at 20-d intervals on three dates from 11 October to 20 November. Drought resistance indices were utilized on the basis of grain yield under end-season drought (Ys) and normal (YN) conditions. Evaluation of MP, HARM, GM, STI, TOL, SSI, RDI, YSI and Yr indicated that late sowing (20 Nov) significantly decreased drought tolerance in all investigated genotypes. However, yield comparisons under normal and terminal drought stress conditions revealed that promising lines (C-81-4, C-81- 10, C-81-14 and C-82-12) had better performance than local checks (Zarrin and Alvand). Furthermore under both moisture conditions C-81-10 genotype had the greatest grain yield. Based on drought indices like as MP, GMP, STI and HARM C-81-10 genotype introduced as the most tolerant genotype to end-season drought stress. Grain yield showed a positive and significant correlation with HARM, GMP, MP, STI and YI indices were more efficient for recognizing high performance genotypes under different sowing dates and diverse moisture stress.


2021 ◽  
Vol 7 (4) ◽  
pp. 18-23
Author(s):  
Roman Boroev ◽  
Mikhail Vasiliev

In this paper, we examine the relationship of the SME index with magnetic storm characteristics and interplanetary medium parameters during the main phase of magnetic storms caused by CIR and ICME events. Over the period 1990–2017, 107 magnetic storms driven by (64) CIR and (43) ICME events have been selected. In contrast to AE and Kp, a stronger correlation is shown to exist between the average SME index (SMEaver) and interplanetary medium parameters during the magnetic storm main phase. Close correlation coefficients between SMEaver and the SW electric field (southward IMF Bz) have been obtained for CIR and ICME events. SMEaver has been found to increase with the rate of magnetic storm development and |Dstmin|. For CIR and ICME events, no difference has been revealed between SMEaver and |Dstmin| in linear regression equations.


2016 ◽  
Vol 5 (5) ◽  
pp. 156-161
Author(s):  
Mehdi Savadkohi Mahforojaki ◽  
Reza Talebi ◽  
Sayyed Saeid Pourdad

In order to evaluate quantitative drought resistance criteria in some safflower genotypes, fiftheen genotypes were evaluated both under moisture stress and non-stress field environments using a randomized complete block design for each environment. The genotypes showed significant differences in grain yield and other traits. Grain yield under irrigated conditions was adversely correlated with water deficit condition, suggesting that high potential yield under optimal conditions does not necessarily result in improved yield under stress conditions. Genotypes G64, G92 and PI253527 showed lower yield reduction than the average of other genotypes. Surprisingly, most of the genotypes showed more than 30% yield reduction under drought stress. The positive correlation between TOL and irrigated yield (Yp) and the negative correlation between TOL and yield under stress (Ys) suggest that selection based on TOL will result in reduced yield under well-watered conditions. We conclude that GMP and STI are able to discriminate tolerant group of genotypes under both environments. Therefore, genotypes G47, G64, G42 and S411 are superior genotypes for both environments. Genotypes S310 , S149 and Almaneriz are more suitable for non-moisture stress than moisture-stress environment.


1957 ◽  
Vol 35 (1) ◽  
pp. 1-13 ◽  
Author(s):  
C. A. Miller

In a severe infestation late-instar spruce budworm larvae that normally feed on current foliage may be forced to complete development on old foliage. This results in a reduction in fecundity. The precise causes of this reduction are not known, but factors that may be involved are the amount and the age of the old foliage consumed. The relationship of pupal case size and fecundity is used as a basis for estimating the expected fecundity in a natural population under these conditions of partial larval starvation. Three regression equations applicable to conditions on the Green River area, New Brunswick, are presented. An index of the actual increase of a population is obtained from an E/F ratio. Ratios may be compared in order to indicate some aspects of oviposition. Actual and expected egg populations can also be compared, subject to certain limitations, to indicate some aspects of adult dispersal. The mean number of eggs per mass in relation to degree of infestation and a simplified method of counting eggs per mass are also discussed.


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