Use of glyphosate to prevent development of reproductive tillers and extend vegetative growth of bent grass (Agrostis castellana)

1996 ◽  
Vol 36 (6) ◽  
pp. 661 ◽  
Author(s):  
RD Hill ◽  
DJ Missen ◽  
RJ Taylor

The effect of glyphosate on seedhead development of bent grass (Agrostis castellana) was evaluated in an experiment at 2 sites in south-western Victoria.Application of glyphosate at 0.1350.225 kg a.i./ha on 7 November and 7 December 1993 prevented the formation of seedheads and stimulated the plant into renewed vegetative growth in response to following summer rain. The treatment with 0.135 kg a.i./ha of glyphosate, applied on 7 November, increased digestible dry matter of the regrowth by 20% and protein content by 70% compared with the unsprayed control which was dominated by seedheads. These results reflect the amount of new growth in treated plots and thus should not be confused with either the 'spraytopping' technique which aims to sterilise seeds after seedhead emergence or 'hay freezing' which and aims to preserve the feed value of existing vegetation by 'chemically curing' standing hay. We conclude that application of glyphosate at 0.135 kg a.i./ha in early November has the potential to reduce the dominance of bent grass, creating an opportunity for follow up fertiliser and management techniques to maintain productive pastures.

1976 ◽  
Vol 86 (1) ◽  
pp. 155-161 ◽  
Author(s):  
A. Hadjichristodoulou

SUMMARYThe effect of stage of harvesting on dry-matter (D.M.) yield and chemical composition of barley, wheat and the legumes common vetch (F. sativa), woollypod vetch (F. dasycarpa) and fodder peas (P. sativum) were studied in Cyprus under low rainfall conditions in a series of trials sown in four successive years. Cereals were harvested at the beginning of heading, 50% heading and the milk stage of grain, and legumes at three stages from preflowering to full pod formation, D.M., protein and digestible D.M. yields and percentage D.M. content increased with age, whereas percentage protein content and D.M. digestibility declined. Under moisture stress conditions before and during the harvesting period D.M. yields did not increase significantly with age. Protein content of cereals under low rainfall conditions was higher than that of cereals grown in the U.K. under higher N fertilization levels. Rainfall conditions affected drastically the performance of both cereals and legumes. However, average yields were satisfactory; the barley variety 628 gave 8·98 t/ha, the highest D.M. yield among all cereal and legume varieties.


1992 ◽  
Vol 72 (3) ◽  
pp. 635-641 ◽  
Author(s):  
A. E. Van Deynze ◽  
P. B. E. McVetty ◽  
R. Scarth ◽  
S. R. Rimmer

To compare the effects of varying seeding rate on the agronomic performance, phenology and seed quality of hybrid and conventional summer rape cultivars, four hybrid and two conventional summer rape cultivars were seeded at 1.5, 3.0, 4.5, 6.0 and 9.0 kg ha−1 at two locations for 3 yr. The hybrid cultivars were, very importantly, 24% higher yielding and produced 50% more total dry matter than the conventional cultivars. The hybrid cultivars were, on average, 1.3% lower in seed oil content, 1.0% higher in seed protein content and equal in sum of oil and protein in the seed compared with the conventional cultivars. The hybrid cultivars were on average, 1.3 d later to 50% flowering and 1.1 d later to maturity than the average for the conventional cultivars, (i.e., equal or earlier to flowering and maturity than Regent). The hybrid cultivars were also 3.9% lower in harvest index and 1.3 ppm lower in chlorophyll content than the conventional cultivars. In spite of these differences, there were no significant cultivar-by-seeding-rate interactions, indicating that the hybrid and conventional cultivars responded similarly to varying seeding rate. Lodging, days to 50% flowering, days to maturity, harvest index, survival, oil content and protein content displayed significant linear responses to varying seeding rate. Stand at maturity, seed yield and total dry matter production displayed significant linear and quadratic responses to varying seeding rate. Varying seeding rate had no effect on seed formation period, the sum of oil and protein content, or chlorophyll content. A seeding rate of 6 kg ha−1 maximized seed yield for both hybrid and conventional summer rape cultivars.Key words: Brassica napus, canola, seed quality, agronomy, phenology


1956 ◽  
Vol 7 (2) ◽  
pp. 98 ◽  
Author(s):  
JN Black

Changes in the pre-emergence distribution of dry matter in subterranean clover (Trifolium subterraneum L.) variety Bacchus Marsh were followed at 21°C, using three sizes of seed and three depths of sowing, ½, 1¼, and 2 in. Decreasing seed size and increasing depth of sowing both reduce the weight of the cotyledons a t emergence. Seed of the three sizes were sown a t three depths in pot culture a t staggered intervals so that emergence was simultaneous. Dry weight in the early vegetative stage was proportional to seed size, and total leaf area and leaf numbers showed similar trends. Plants of each seed size grew at the same relative rate. No effect of depth of sowing could be detected, and this was shown to be due to the cotyledon area a t emergence being constant for any given seed size, regardless of varying depth of sowing and hence of cotyledon weight. It was concluded that seed size in a plant having epigeal germination and without endosperm is of importance: firstly, in limiting the maximum hypocotyl elongation and hence depth of sowing, and secondly, in determining cotyledon area. Cotyledon area in turn influences seedling growth, which is not affected by cotyledon weight. Once emergence has taken place, cotyledonary reserves are of no further significance in the growth of the plants.


2018 ◽  
Vol 34 (3) ◽  
pp. 345-353 ◽  
Author(s):  
Violeta Mandic ◽  
Zorica Bijelic ◽  
Vesna Krnjaja ◽  
Aleksandar Simic ◽  
Maja Petricevic ◽  
...  

Maize is the very important silage source in the world. Timely harvesting ensure high maize forage yield and quality. Therefore, the study focused on the effects of four harvesting times (starting at the 12 August every 7 days) on yield and qualitative parameters of forage green mass of maize hybrid ZP 677. The experiment was set in Vojvodina Province, Serbia, during the 2013 and 2014 growing seasons. Plant height, stem diameter, number of leaves per plant, ear percentage, forage yield, dry matter content and crude protein content were higher, while stem percentage was lower in 2014 with favorable climatic condition. Forage yield, crude protein content, ADF and NDF decreased, while dry matter content significantly increased with delay in harvesting. The maize hybrid should be harvested when the milk line is three-quarter of the way down the grain that is in the third decade of August.


Author(s):  
João A. da Silva ◽  
Sérgio L. R. Donato ◽  
Paulo E. R. Donato ◽  
Evilasio dos S. Souza ◽  
Milton C. Padilha Júnior ◽  
...  

ABSTRACT The objective was to evaluate the effect of different spacings and mineral fertilizations on cactus pear growth and production in a randomized block design, with three replicates, in a 3 x 4 factorial scheme: three spacings, 1.00 x 0.50 m, 2.00 x 0.25 m and 3.00 x 1.00 x 0.25 m, and four fertilizations, 000-000-000, 000-150-000, 200-150-000 and 200-150-100 kg ha-1 of N, P2O5 and K2O, respectively. Plant growth was evaluated between 90 and 390 days and production and growth were evaluated at 620 days after planting. There were significant interactions between spacing and fertilization for plant height, number of cladodes and cladode area index from 90 to 390 days and for production of fresh and dry matter at 620 days after planting. Spacing influenced cladode area index, while fertilization influenced plant height, number of cladodes and cladode area index at 620 days after planting. Plant height showed cubic effect for the days after planting. Number of cladodes and cladode area index were dependent on spacing, fertilization and plant age, and fitted to cubic models. The best results of growth and production of fresh and dry matter are associated with NPK and NP fertilizations and the spacing of 1.00 x 0.50 m.


2008 ◽  
Vol 19 (3) ◽  
pp. 252 ◽  
Author(s):  
O. NISSINEN ◽  
P. KALLIAINEN ◽  
L. JAUHIAINEN

The development of the yield and nutritive value of timothy (Phleum pratense L.) both in the primary growth and in the regrowth were studied at MTT Plant Production Research, a unit of MTT Agrifood Research Finland, in Rovaniemi (66°35´N) in 1999–2001. The dry matter yield and leaf:stem ratio were measured from the crop samples, and the contents of crude protein and organic matter digestibility of both whole plant samples and leaf and stem fractions were analysed. In primary growth, the most rapid increase of dry matter, 220–240 kg ha-1 per day, was measured around the beginning of the heading stage. There was a very strong positive correlation between the proportion of stems and the amount of dry matter in the primary yield. The daily growth rate of the regrowth was less than half of that of the primary growth. The fastest decrease, 1 percentage unit per day, in crude protein content was measured at the pasture stage (4–5-leaf stage). During the entire sampling period, the average daily decline in crude protein content in the primary growth of timothy was 0.65 percentage units. The main cause for the rapid decline in crude protein content was the high proportion of stem matter and its low protein content. In the regrowth, during the last four weeks before the harvest, the average daily decline in crude protein content was 0.28 percentage units.The average decline in organic matter digestibility from early pasture stage to late silage stage was 0.9 percentage units per day. The most remarkable change was noticed at the growth stage of timothy when about the half of stems were heading and it was then that the digestibility decreased by more than one percentage unit per day. The rapid decline in organic matter digestibility was due to the low digestibility of stem matter. The daily change in forage digestibility in the regrowth was very small, on average 0.11%.;


2013 ◽  
Vol 59 (4) ◽  
pp. 167-177
Author(s):  
Miriam Kizeková ◽  
Ján Tomaškin ◽  
Jozef Čunderlík ◽  
Ľubica Jančová ◽  
Janka Martincová

Abstract This study highlights the effect of drought and ambient temperature on performance and herbage quality of legume monocultures and grass-legume mixtures. In a field experiment, the total dry matter yield, seasonal pattern of dry matter yield distribution, content of crude protein and crude fibre of monocultures of red clover and alfalfa and grass-legume mixtures were investigated during two consecutive dry years (2011-2012). Alfalfa cultivars Kamila and Tereza grown as monocultures or as mixtures with Festulolium braunii (cultivar Achilles) outperformed the red clover cultivars Fresko and Veles and provided a well-balanced total and seasonal dry matter yield during both years. Across all experimental years, crude protein content was significantly higher at alfalfa monocultures and mixture when compared with clover monocultures (P < 0.05). However, considerable lower content of crude fibre at clover monocultures in comparison with alfalfa ones was found. Responses of nutritive parameters of both legume species to weather variables were different. Crude protein content in red clover was independent of rainfall and temperature. In contrast, the crude fibre content correlated with temperature whereby the alfalfa monocultures showed stronger correlations (P < 0.05) than red clover monocultures.


2019 ◽  
Vol 11 (4) ◽  
pp. 197
Author(s):  
Diogo Mendes da Silva ◽  
Suzan Kelly Vilela Bertolucci ◽  
Smail Aazza ◽  
Alexandre Alves de Carvalho ◽  
Simony Carvalho Mendonça ◽  
...  

The purpose of the present work was to evaluate the vegetative growth of Mentha piperita L. cultivated under different water availability, as well its influence in content, chemical composition and in vitro antioxidant activity of its essential oil. Plants were propagated by mother plants microcutting and scions were transplanted to 5 L pots with soil and cattle manure. Afterward, were kept at field capacity for 30 days and under treatment for 40 days. It was treated with different levels of water deficit treatments: (T1): 100 of field capacity (FC); (T2): 80 of FC; (T3): 60 of FC; (T4) 40 of FC with 5 blocks. Vegetative growth was evaluated by dry matter contents of all part of plants and by root/aerial rate. The essential oil of the leaves was extracted by hydrodistillation, analyzed by GC-FID and GC-MS and in vitro antioxidant potential was evaluated. A significant decrease in the dry matter of leaves and stems accompanied with a decrease in the roots dry matter was observed with an increase in the water stress. Quantitative chemical differences were observed in the chemical composition of the essential oil, according water availability. Total antioxidant activity showed a gradual increase as water stress progressed.


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