SOME EFFECTS OF NITRATE ON SOYBEAN ROOT DEVELOPMENT

1986 ◽  
Vol 66 (3) ◽  
pp. 505-510 ◽  
Author(s):  
J. A. STONE ◽  
B. R. BUTTERY

The objective of this study was to determine the effect of nitrate on some morphological aspects of soybean (Glycine max (L.) Merr.) root growth and to determine the role of drainage in the response. Two indeterminate soybean cultivars were grown on 0, 10 and 40% mixtures of perlite and Brookston clay loam, supplied with Bradyrhizobium japonicum strain USDA 110, and watered with nutrient solutions containing 0 or 6 mM nitrate. Plants were grown in acrylic tubes until 21 and 53 d after emergence in corresponding field and growth room experiments, respectively. Response variables measured were the rate of taproot extension, root counts at the acrylic-soil interface, and top, root, and nodule dry weight. Nitrate suppressed nodule development and increased top dry weight but had no effect on the rate of taproot extension. Nitrate increased root counts and root dry weights in the field test, but decreased root counts in the growth room test. Top:root ratio was increased in the growth room but not in the field test. Increasing the proportion of perlite generally increased rates of root extension, root counts, and top dry weights in the field and growth room experiments. However, the soil mixture had no effect on nodule dry weight at either location, or on root dry weight in the growth room.Key words: Root extension, Glycine max, indeterminate, drainage

1997 ◽  
Vol 77 (2) ◽  
pp. 201-205 ◽  
Author(s):  
D. L. Pazdernik ◽  
P. H. Graham ◽  
J. H. Orf

We have previously identified differences among soybean [Glycine max (L.) Merr.] lines in early nodulation and N2 fixation, and related early nodule development and overall plant performance under N-limited field conditions. The objectives of the present study were: 1) to estimate heritabilities for nodule fresh weight (NFW), shoot dry weight (SDW), and root dry weight (RDW) determined 17 d after inoculation (DAI); 2) to examine genetic variation for total nodule soluble protein (TSOLP) at 17 DAI, and SDW and shoot N derived from fixation (SNdfa) at the R5 growth stage; and 3) to assess relationships between early nodulation and subsequent R5 shoot mass and SNdfa. The two populations used were derived from the Minnesota-adapted cultivars Kasota and Parker, and two plant introductions PI 437966 and PI 384469B. Genetic variances within populations were significant for most traits measured at 17 DAI, and at the R5 growth stage. Heritability estimates ranged from 0.79–0.82 for NFW, 0.51–0.56 for SDW, and 0.38–0.40 for RDW, with SDW also correlated with seed size at 17 DAI (r = 0.88**). Additional correlation analyses showed SNdfa correlated with NFW (r = 0.33**) and TSOLP (r = 0.46**). The results of this study suggest that gains from selection are possible for NFW and SDW at early stages of plant development. Key words: Glycine max (L.) Merr., nodulation, nitrogen fixation, heritabilitynot available


Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 788
Author(s):  
Shaban R. M. Sayed ◽  
Shaimaa A. M. Abdelmohsen ◽  
Hani M. A. Abdelzaher ◽  
Mohammed A. Elnaghy ◽  
Ashraf A. Mostafa ◽  
...  

The role of Pythium oligandrum as a biocontrol agent against Pythium aphanidermatum was investigated to avoid the harmful impacts of fungicides. Three isolates of P. oligandrum (MS15, MS19, and MS31) were assessed facing the plant pathogenic P. aphanidermatum the causal agent of Glycine max damping-off. The tested Pythium species were recognized according to their cultural and microscopic characterizations. The identification was confirmed through sequencing of rDNA-ITS regions including the 5.8 S rDNA. The biocontrol agent, P. oligandrum, isolates decreased the mycelial growth of the pathogenic P. aphanidermatum with 71.3%, 67.1%, and 68.7% through mycoparasitism on CMA plates. While the half-strength millipore sterilized filtrates of P. oligandrum isolates degrade the pathogenic mycelial linear growth by 34.1%, 32.5%, and 31.7%, and reduce the mycelial dry weight of the pathogenic P. aphanidermatum by 40.1%, 37.4%, and 36.8%, respectively. Scanning electron microscopy (SEM) of the most effective antagonistic P. oligandrum isolate (MS15) interaction showed coiling, haustorial parts of P. oligandrum to P. aphanidermatum hyphae. Furthermore, P. oligandrum isolates were proven to enhance the germination of Glycine max seedling to 93.3% in damping-off infection using agar pots and promote germination of up to 80% during soil pot assay. On the other hand, P. oligandrum isolates increase the shoot, root lengths, and the number of lateral roots.


Weed Science ◽  
1979 ◽  
Vol 27 (3) ◽  
pp. 278-279 ◽  
Author(s):  
W. S. Hardcastle

Twenty-eight commercial soybean [Glycine max(L.) Merr.] cultivars of maturity classes V through VIII were evaluated for differences in response to metribuzin [4-amino-6-tert-butyl-3-(methylthio)-as-triazin-5(4H)-one] 0.125 ppm w/w in hydroponic culture. Top dry weight (TDW) of treated ‘FFR 666’ soybeans equaled that of the cultivar check and five other cultivars were not significantly different (P = 5%). ‘Semmes' was most sensitive to the herbicide with TDW 40% of cultivar check. ‘Tracy’ and ‘Coker 156’ were not significantly different (P = 5%) from Semmes. The other cultivars tested were intermediate in response to metribuzin.


2007 ◽  
Vol 193 (3) ◽  
pp. 177-188 ◽  
Author(s):  
T. L. Henshaw ◽  
R. A. Gilbert ◽  
J. M. S. Scholberg ◽  
T. R. Sinclair

2019 ◽  
Vol 70 (7) ◽  
pp. 585 ◽  
Author(s):  
Xiaoning Cao ◽  
Tingting Wu ◽  
Shi Sun ◽  
Cunxiang Wu ◽  
Caijie Wang ◽  
...  

Root traits are essential for optimising nutrient and water absorption and anchorage. However, changes in root traits and the contribution of root-to-shoot growth and development of soybean (Glycine max (L.) Merr.) across a century of breeding are poorly documented. In this study, we adopted a grafting technique, using 55 cultivars released in the three main soybean-production regions in China as rootstocks in a pot experiment and 24 cultivars from the Yellow-Huai-Hai Valley (YHH) region as rootstocks in a field experiment, with cv. Zigongdongdou as the common scion. Changes in soybean roots, including dry weight (DW) of roots, lateral root number (LRN) and taproot length (TRL), and their contribution to shoot development and biomass formation, including shoot DW, plant height and node number, were evaluated under optimal conditions in 2011. Aboveground traits declined with year of release in the YHH region and did not vary over time in the northern Heilongjiang province and mid-south Heilongjiang region except for shoot DW. The root traits root DW, LRN and TRL were similar over years of release in the pot and field experiments. The results suggest that the newer cultivars have lesser shoot growth and root capacity but the same amount of root growth as older cultivars. Root traits did not change during selection, suggesting that improvement in soybean root traits should be an aim in future breeding.


2009 ◽  
Vol 89 (2) ◽  
pp. 265-272
Author(s):  
L. R. Brown ◽  
D. E. Robinson ◽  
K. Chandler ◽  
C. J. Swanton ◽  
R. E. Nurse ◽  
...  

There have been anecdotal accounts of increased crop sensitivity due to herbicide drift followed by an in-crop herbicide. An experiment was conducted from 2005 to 2007 at Elora, Ridgetown, and Woodstock, Ontario, to determine the effects of simulated mesotrione drift followed by in-crop applications of glyphosate, imazethapyr, bentazon and glyphosate plus chlorimuron on glyphosate-resistant soybean [Glycine max (L.) Merr.] visual injury, plant height, plant density, shoot dry weight, and seed yield. As the rate of simulated mesotrione drift increased, there was an increase in soybean injury and a decrease in shoot dry weight, height, and yield. Simulated mesotrione drift followed by bentazon resulted in synergistic responses in injury shortly after application in some environments. This increase in injury was transient, with no synergistic responses in density, shoot dry weight, and yield. In contrast, antagonistic responses were observed when glyphosate, imazethapyr, or glyphosate plus chlorimuron were applied after simulated mesotrione drift in some environments. Further research is required to develop a better understanding of the interactions of drift followed by the application of an in-crop herbicide. Key words: Bentazon, chlorimuron, glyphosate, imazethapyr, mesotrione, synergism


Author(s):  
Ogbuehi HC ◽  
Ibe PK

A pot experiment was conducted under rainfed condition to study the effect of water hyacinth compost on the morpho-physiological parameters of soybean (Glycine max L.) at the Teaching and Research Farm of Faculty of Agriculture and Veterinary Medicine, Imo State University, Owerri. The treatments were control (T1) 100g (T2), 150g (T3) and 200g (T4) of water hyacinth compost and replicated four times. The treatments were arranged in Complete Randomized Design (CRD). The parameters measured were plant height, number of leaves, leaf area (cm2), leaf area index, relative growth rate (RGR), Net assimilation rate (NAR), shoot dry weight(g), yield and yield components (Number of pods, pods weight, 100 seed weight). The results obtained indicated that T3 significantly produced highest plant height (57.6cm) compare to control. While it was observed that T4 (200g) significantly produced the highest number of leaves (233.25), leaf area (631.80cm2), shoot dry weight (15.445g), number of pods (129.75), pod weights (25.38g) seed weight (7.23g) and yield (0.72kg/ha) relative to control and other treatment levels. Root parameters were also significantly improved by the rates of water hyacinth application compared to control. It will be worthy to note that there was no nodulation perhaps that was why the yield was poor. The results showed that soybean growth can effectively be improved with incorporation of water hyacinth into soil.


Sign in / Sign up

Export Citation Format

Share Document