Nitrogen partitioning and cycling in barley-soil systems under conventional and zero tillage in central Alberta

1993 ◽  
Vol 73 (2) ◽  
pp. 183-196 ◽  
Author(s):  
K. Haugen-Kozyra ◽  
N. G. Juma ◽  
M. Nyborg
Keyword(s):  
Hordeum Vulgare ◽  
Nitrogen Partitioning ◽  
Urea Solution ◽  
Organic N ◽  
N Recovery ◽  
Growth Stages ◽  
Zero Tillage ◽  
Hordeum Vulgare L ◽  
Soil Systems ◽  
Microbial N

Cropping systems which conserve soil, water and nutrients are needed on the Canadian prairies. The objectives of this study were: (1) to assess the effects of urea injection on N partitioning in barley-soil systems under conventional (CT) and zero tillage (ZT); and (2) to measure the dynamics of fertilizer and soil N over the growing season. Twelve microplots were installed in each of CT and ZT plots located on a Black Chernozemic soil and were fertilized (59 kg N ha−1) with 15N urea solution, sown to barley (Hordeum vulgare (L.) 'Empress') and destructively sampled at the fifth leaf, ear emergence, grain filling and ripening growth stages. Distribution of 14N and 15N in shoots, roots, mineral N, microbial N, and soil organic N were measured. The recovery of fertilizer N in the soil-plant system was not different between treatments. Microbial N and non-microbial organic N accounted for > 80% of residual 15N in both treatments. Nitrogen budgets showed that grain removal from CT was 76 kg ha−1 and 56 kg ha−1 in ZT. Our study suggests that more 15N from injected urea was converted to organic N under ZT than CT; thus ZT systems have the potential of conserving N. Tillage practices affect the fate of added N. Key words: Typic Cryoboroll, 15N, organic matter, Hordeum vulgare, N recovery, zero tillage

ANNUAL WEED CONTROL WITH PARAQUAT IN COMBINATION WITH OTHER HERBICIDES

1986 ◽  
Vol 66 (1) ◽  
pp. 153-160 ◽  
Author(s):  
J. T. O’DONOVAN ◽  
P. A. O’SULLIVAN
Keyword(s):  
Triticum Aestivum ◽  
Hordeum Vulgare ◽  
Weed Control ◽  
Avena Sativa ◽  
Brassica Campestris ◽  
Triticum Aestivum L ◽  
Field Trials ◽  
Zero Tillage ◽  
Hordeum Vulgare L ◽  
Key Words Wheat

Paraquat at 0.28 kg/ha effectively controlled barley (Hordeum vulgare L. ’Galt’), wheat (Triticum aestivum L. ’Neepawa’) and oat (Avena sativa L. ’Random’) in field trials conducted during 1982 and 1983. Grass control was excellent with paraquat and its activity was unaffected when it was applied in combination with either clopyralid, picloram, metribuzin, linuron, or chlorsulfuron. Slight reductions in paraquat phytotoxicity occurred in some instances when paraquat was applied in combination with commercially formulated mixtured of clopyralid plus 2,4-D, clopyralid plus MCPA or picloram plus 2,4-D, but grass control was still acceptable (90% or greater). However, a commercially formulated mixture of cyanazine plus MCPA consistently reduced the phytotoxicity of paraquat and rendered grass control unacceptable. Control of rapeseed (Brassica campestris L. ’Candle’) with paraquat and most paraquat mixtures was excellent in 1982 but was poor and variable in 1983.Key words: Wheat, barley, oat, rapeseed, zero tillage, chemical summerfallow

scholarly journals The Pattern of Lignin Deposition in The Cell Walls of Internodes During Barley (Hordeum vulgare L.) Development

2015 ◽  
Vol 57 (2) ◽  
pp. 55-66 ◽  
Author(s):  
Lidija Begović ◽  
Jelena Ravlić ◽  
Hrvoje Lepeduš ◽  
Dunja Leljak-Levanić ◽  
Vera Cesar
Keyword(s):  
Cell Wall ◽  
Hordeum Vulgare ◽  
Peroxidase Activity ◽  
Cell Walls ◽  
Grain Filling ◽  
Deposition Process ◽  
Growth Stages ◽  
Hordeum Vulgare L ◽  
Anatomical Changes ◽  
Lignin Deposition

Abstract The aim of this paper is to elucidate relationship between anatomical changes and lignin deposition dynamics in the cell wall of barley (Hordeum vulgare L.) internodes during four growth stages: heading, flowering, grain filling and ripening. Microscopy was used to analyze anatomical changes related to lignin deposition whereas peroxidase activity was spectrophotometrically determined. In transversal sections lignin was found to be predominant in the sclerenchyma ring in cortex, where particularly lignified cell walls were found. Peroxidase activity was increased in older internodes and their localization in situ was in positive correlation with tissue lignification. Our results showed that, depending on the cultivar, at the flowering and grain filling stages intensive lignin synthesis and deposition occurred. This showed that deposition of lignin in the cell wall at a particular growth stage is in correlation with the lodging resistant phenotype of the investigated cultivars. The results contribute to the understanding of the lignin deposition process during barley development and consequential cell wall thickness.

Ultrastructure and Senescence in an Achloroplastic Mutant of Hordeum vulgare L. cv. Dyan

1992 ◽  
Vol 50 (1) ◽  
pp. 844-845
Author(s):  
R.H.M. Cross ◽  
C.E.J. Botha ◽  
A.K. Cowan ◽  
B.J. Hartley
Keyword(s):  
Cell Wall ◽  
Hordeum Vulgare ◽  
Leaf Tissue ◽  
Ultrastructural Changes ◽  
Hordeum Vulgare L ◽  
Mesophyll Cells ◽  
Lethal Mutant ◽  
Cytoplasmic Matrix ◽  
Close Proximity ◽  
Pinocytotic Vesicles

Senescence is an ordered degenerative process leading to death of individual cells, organs and organisms. The detection of a conditional lethal mutant (achloroplastic) of Hordeum vulgare has enabled us to investigate ultrastructural changes occurring in leaf tissue during foliar senescence.Examination of the tonoplast structure in six and 14 day-old mutant tissue revealed a progressive degeneration and disappearance of the membrane, apparently starting by day six in the vicinity of the mitochondria associated with the degenerating proplastid (Fig. 1.) where neither of the plastid membrane leaflets is evident (arrows, Fig. 1.). At this stage there was evidence that the mitochondrial membranes were undergoing retrogressive changes, coupled with disorganization of cristae (Fig. 2.). Proplastids (P) lack definitive prolamellar bodies. The cytoplasmic matrix is largely agranular, with few endoplasmic reticulum (ER) cisternae or polyribosomal aggregates. Interestingly, large numbers of actively-budding dictysomes, associated with pinocytotic vesicles, were observed in close proximity to the plasmalemma of mesophyll cells (Fig. 3.). By day 14 however, mesophyll cells showed almost complete breakdown of subcellular organelle structure (Fig. 4.), and further evidence for the breakdown of the tonoplast. The final stage of senescence is characterized by the solubilization of the cell wall due to expression and activity of polygalacturonase and/or cellulose. The presence of dictyosomes with associated pinocytotic vesicles formed from the mature face, in close proximity to both the plasmalemma and the cell wall, would appear to support the model proposed by Christopherson for the secretion of cellulase. This pathway of synthesis is typical for secretory glycoproteins.

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