Effect of rotation and cultivation systems on establishment and persistence of annual medics

1989 ◽  
Vol 29 (2) ◽  
pp. 183 ◽  
Author(s):  
EJ Crawford ◽  
BG Nankivell
Keyword(s):  
Lower Proportion ◽  
The Other ◽  
Annual Plant ◽  
Plant Populations ◽  
The Third ◽  
Permanent Pasture ◽  
Seed Reserves ◽  
Annual Medics ◽  
Annual Medicago ◽  
Medicago Species

The persistence and annual and seasonal regeneration of 3 annual Medicago species, M. rugosa cv. Paragosa, M. scutellata cv. Robinson and M. truncatula cvv. Cyprus and Jemalong, were compared between 1978 and 1985 over 3 rotation systems, permanent pasture (R1); pasture, barley, pasture, barley repeated (R2) and pasture, fallow, wheat, barley, repeated (R3). Ploughing practices adopted for the various rotations affected persistence and regeneration. Not all ofthe seed that was produced in 1978 produced seedlings. A much lower proportion of the seed reserve of cv. Paragosa produced seedlings compared with cv. Robinson and cvv. Cyprus and Jemalong. The poorer re-establishment of cv. Paragosa could have been due to its more permeable seed compared with the other cultivars. Seed reserves persisted for a maximum of 7 years. Annual re-establishment was greater for all cultivars under the system of permanent pasture than under either the pasture, barley or the pasture, fallow, wheat, barley rotations which disturbed the soil. Unlike the other cultivars, germination and establishment rates of cv. Robinson were low following the first autumn rains in all years. Germination of this cultivar usually occurred from June to November following a delayed breakdown in hardseededness. It also responded to cultivation so that with the exception of R2 in 1980, the highest annual plant populations in R2 and R3 were in the cropping and/or fallowing phases rather than the pasture phases. Although cv. Paragosa produced the highest seed yield in the year of sowing, its reserves were exhausted by the third year in all rotations, whereas the harder seeded cultivars maintained adequate seed reserves to enable good plant re-establishment in the sixth year under all rotations, except in the continuous pasture rotation, where seed reserves of cv. Robinson were exhausted by the fifth year. Cultivation and consequent pod burial in the 2 cropping rotations preserved seeds longer than did the continuous pasture system. Jemalong maintained higher (P< 0.05) seed reserves than cvv. Cyprus and Robinson in the sixth year.

A comparison of the persistence of Medicago truncatula cv. Paraggio with other annual medics in the Victorian Mallee

1993 ◽  
Vol 33 (4) ◽  
pp. 443 ◽  
Author(s):  
RA Latta ◽  
PE Quigley
Keyword(s):  
Plant Regeneration ◽  
Seed Production ◽  
Medicago Truncatula ◽  
Seed Set ◽  
Agricultural Productivity ◽  
The Other ◽  
Plant Densities ◽  
Seed Reserves ◽  
Annual Medics ◽  
Better Than

The annual medic Medicago truncatula cv. Paraggio has been widely sown in pastures throughout the Victorian Mallee region; however, its ability to persist in cereal pasture rotations is not known. Seed permeability and production, and plant regeneration of Paraggio, were studied in the field over 4 years, and the changes in its seed reserve were examined under 3 different cereal-pasture rotations. When compared with medic cvv. Parabinga, Harbinger, and Jemalong, Paraggio had up to twice the level of permeable seed over the summer-autumn period in 2 years (7-36% v. 2.5-19%). Paraggio produced 336-928 kg/ha of seed over 3 years, and after seed production was halted, it regenerated at densities of 150-1438 plants/m2 over the next 4 years. These results were generally the same as, or better than, the other cultivars. When seed set occurred in 1 and 2 years in the pasture phase of a 2- and 3-year rotation, respectively, Paraggio seed reserves were maintained at >4000 seeds/m2. This study demonstrated that Paraggio resulted in superior plant densities when grown in a number of typical rotations. It persisted satisfactorily and is expected to improve agricultural productivity in shor-tterm cereal-pasture rotations.

Nodulation and growth of pasture legumes with naturalised soil rhizobia. 1. Annual Medicago spp.

2000 ◽  
Vol 40 (7) ◽  
pp. 939 ◽  
Author(s):  
R. A. Ballard ◽  
N. Charman
Keyword(s):  
Dry Matter ◽  
Early Growth ◽  
The Other ◽  
Dry Matter Production ◽  
Soil Suspension ◽  
Pasture Legumes ◽  
Matter Production ◽  
Annual Medics ◽  
Annual Medicago ◽  
Inoculation Treatment

The ability of 11 species of annual medics (Medicago doliata, M. laciniata, M. littoralis, M. minima, M. orbicularis, M. polymorpha, M. praecox, M. rigidula, M. rigiduloides, M. tornata and M. truncatula) to nodulate and fix nitrogen with naturalised rhizobia from 28 South Australian soils was assessed. The number of rhizobia in the soils was estimated. Medic shoot dry matter production and nodulation were measured, after inoculation of medic seedlings with a soil suspension, in 2 glasshouse experiments. The number of medic rhizobia ranged from 0.4 10 2 to 1.5 10 6 per gram soil. Medicago laciniata was the only medic species tested which was not consistently nodulated by the soil rhizobia. While all the other species formed nodules, they varied widely in their ability to form an effective symbiosis. Symbiotic performance (which indicates how much growth the medic line achieved, when compared to an effective inoculation treatment) of the medic species ranged from 3% (M. rigiduloides) to 67% (M. praecox). Herald (M. littoralis) achieved a symbiotic performance of 49% and it was estimated that this would be insufficient to meet the nitrogen requirements of a Herald-based pasture during early growth. The symbiotic performance of Santiago (M. polymorpha) was low (17%) and erratic (from –6 to 72%). The ability of the rhizobia to form an effective symbiosis varied widely also between soil regions. For example, the rhizobia in Riverland soils resulted in only 31% of the shoot dry matter of those in Eyre Peninsula soils, in association with M. polymorpha. There are significant opportunities to improve the symbiotic performance of a number of the species of annual medics examined in this study. Options to improve the effectiveness of the symbiosis of medics with naturalised soil rhizobia are discussed.

scholarly journals DESCRIPCIÓN DEL HÁBITO ALIMENTARIO DE DOCE ESPECIES DE PECES ASOCIADOS A LA CIÉNAGA GRANDE DE SANTA MARTA, COLOMBIA

2016 ◽  
Vol 43 (1) ◽  
Author(s):  
Dáninso Gámez Barrera ◽  
Eliana Morón Granados ◽  
Juan Fuentes Reines
Keyword(s):  
Oreochromis Niloticus ◽  
Food Composition ◽  
Lower Proportion ◽  
The Other ◽  
Time And Space ◽  
Southeastern Part ◽  
Fish Feeding ◽  
The Third ◽  
Fish Predators ◽  
Mugil Incilis

Changes in food composition of 12 species of fishes from the southeastern part of the Ciénaga Grande de Santa Marta, Colombia were evaluated; a total of 2035 individuals were sampled. Significant changes in food composition with size, time and space were observed, mainly in Ariopsis sp., Cathorops mapale, Lycengraulis batesii, Astyanax magdalenae, and Aequidens pulcher. Regarding diet similarity between species, two main groups were observed. The first one was divided in three subgroups: one characterized by fish foraging on insects and zooplankton is composed by A. magdalenae and Roeboides dayi; the second one is composed by the generalists Ariopsis sp., L. batesii, and A. pulcher, and the third one by fish predators Caquetaia kraussii and C. mapale. The other group was characterized by fish feeding on phytoplankton and in a lower proportion on detritus and zooplankton (Oreochromis niloticus, Mugil incilis, M. liza, and M. curema) or on detritus (Cyphocharax magdalenae).

Annual Medicago species in Morocco. I. Species and their abundance

1992 ◽  
Vol 43 (3) ◽  
pp. 739 ◽  
Author(s):  
M Bounejmate ◽  
PE Beale ◽  
AD Robson
Keyword(s):  
Seed Yield ◽  
Genetic Erosion ◽  
Soil Surface ◽  
Annual Medics ◽  
Annual Medicago ◽  
Medicago Species ◽  
Collection Sites

An ecogeographic survey of the distribution of annual medics in Morocco was conducted in 1988 by sampling 161 sites within six agricultural zones. At each site all medic pods lying on the soil surface were collected from five quadrats placed at random. Of the 18 medic species reported to occur in Morocco, only 11 were recorded in 1988. M. polymorpha and M. truncatula were the most frequent. Thirty-five sites had no medics in quadrats and 15 sites had no medics in the near vicinity. The average seed yield for all collection sites was 12.6 kg ha-1. Nearly 60% of the sites yielded less than 20 kg ha-1. More than 50 kg seed ha-1 was recorded at less than 10% sites. Maximum seed yield at any site was only of 169 kg ha-1. Results suggest that genetic erosion is occurring but occasional sites can be found where medics are abundant.

Effect of water stress on the phasic development of annual Medicago species

1976 ◽  
Vol 27 (2) ◽  
pp. 227 ◽  
Author(s):  
NM Clarkson ◽  
JS Russell
Keyword(s):  
Water Stress ◽  
Life Span ◽  
Mean Delay ◽  
Severe Water Stress ◽  
Eastern Australia ◽  
The Mean ◽  
Annual Medics ◽  
Annual Medicago ◽  
Delayed Flowering ◽  
Medicago Species

Although annual medics (Medicago spp.) grow and persist in subtropical eastern Australia, their growth in the field is greatly affected by water stress, which can occur at any time after germination. To study this effect in some detail, the phasic development of six annual Medicago cultivars was measured under four water regimes in a glasshouse. Stress was varied by allowing the soil to dehydrate to different degrees before rewetting, the cycles being repeated continuously. Water stress delayed flowering in all medics except M. scutellata, the mean delay being 14 days. Corresponding delays occurred in the onset of pod production. In contrast the later stages of phasic development were accelerated in some species. Both the length of flowering and life span of the M. truncatula cultivars were significantly reduced by water stress. In the case of cv. Jemalong, severe water stress reduced its length of flowering by 53 days and its life span by 27 days. These results suggest that annual medics have no mechanisms for evading dry seasonal conditions by earlier flowering, but once flowering has begun phasic development is accelerated in some species by water stress. The implications of this study for the interpretation and prediction of field behaviour of annual medics are that water stress can affect phasic development mainly through a delay in flowering. However, the effects appear to be small compared with those due to vernalization, photoperiod and temperature.

Efficacy of some insecticide modules against major insect pests and spider population of rice, Oryza sativa L.

ENTOMON ◽  
2018 ◽  
Vol 43 (4) ◽  
pp. 257-262
Author(s):  
Atanu Seni ◽  
Bhimasen Naik
Keyword(s):  
Oryza Sativa ◽  
Grain Yield ◽  
Untreated Control ◽  
Insect Pests ◽  
Oryza Sativa L ◽  
Gall Midge ◽  
Stem Borer ◽  
The Other ◽  
The Third ◽  
Treated Plot

Experiments were carried out to assess some insecticide modules against major insect pests of rice. Each module consists of a basal application of carbofuran 3G @ 1 kg a.i ha-1 at 20 DAT and Rynaxypyr 20 SC @ 30 g a.i ha-1 at 45 DAT except untreated control. All modules differ with each other only in third treatment which was applied in 65 DAT. The third treatment includes: Imidacloprid 17.8 SL @ 27 g a.i ha-1, Pymetrozine 50 WG @ 150 g a.i ha-1, Triflumezopyrim 106 SC @ 27 g a.i ha-1, Buprofezin 25 SC @ 250 g a.i ha-1; Glamore (Imidacloprid 40+Ethiprole 40% w/w) 80 WG @ 100 g a.i. ha-1, Thiacloprid 24 SC @ 60 g a.i ha-1, Azadirachtin 0.03 EC @ 8 g a.i ha-1, Dinotefuran 20 SG@ 40 g a.i ha-1 and untreated control. All the treated plots recorded significantly lower percent of dead heart, white ear- head caused by stem borer and silver shoot caused by gall midge. Module with Pymetrozine 50 WG @ 150 g a.i ha-1 treated plot recorded significantly higher per cent reduction of plant hoppers (>80% over untreated control) and produced higher grain yield (50.75 qha-1) than the other modules. Among the different treated modules the maximum number of spiders was found in Azadirachtin 0.03 EC @ 8 g a.i ha-1 treated module plot followed by other treatments.

Retroaktive Neuverhandlung

2018 ◽  
Vol 63 (1) ◽  
Author(s):  
Daniel Martin Feige
Keyword(s):  
Original Work ◽  
The Other ◽  
Final Part ◽  
Critical Reading ◽  
The Third ◽  
Works Of Art ◽  
The Relationship

Der Beitrag widmet sich der Frage historischer Folgeverhältnisse in der Kunst. Gegenüber dem Gedanken, dass es ein ursprüngliches Werk in der Reihe von Werken gibt, das späteren Werken seinen Sinn gibt, schlägt der Text vor, das Verhältnis umgekehrt zu denken: Im Lichte späterer Werke wird der Sinn früherer Werke neu ausgehandelt. Dazu geht der Text in drei Schritten vor. Im ersten Teil formuliert er unter der Überschrift ›Form‹ in kritischer Abgrenzung zu Danto und Eco mit Adorno den Gedanken, dass Kunstwerke eigensinnig konstituierte Gegenstände sind. Die im Gedanken der Neuverhandlung früherer Werke im Lichte späterer Werke vorausgesetzte Unbestimmtheit des Sinns von Kunstwerken wird im zweiten Teil unter dem Schlagwort ›Zeitlichkeit‹ anhand des Paradigmas der Improvisation erörtert. Der dritte und letzte Teil wendet diese improvisatorische Logik unter dem Label ›Neuaushandlung‹ dann dezidiert auf das Verhältnis von Vorbild und Nachbild an. The article proposes a new understanding of historical succession in the realm of art. In contrast to the idea that there is an original work in the series of works that gives meaning to the works that come later, the text proposes to think it exactly the other way round: in the light of later works, the meanings of earlier works are renegotiated. The text proceeds in three steps to develop this idea. Under the heading ›Form‹ it develops in the first part a critical reading of Danto’s and Eco’s notion of the constitution of the artworks and argues with Adorno that each powerful work develops its own language. In the second part, the vagueness of the meaning of works of art presupposed in the idea of renegotiating earlier works in the light of later works is discussed under the term ›Temporality‹ in terms of the logic of improvisation. The third and final part uses this improvisational logic under the label ›Renegotiation‹ to understand the relationship between model and afterimage in the realm of art.

Features of the course and treatment of glaucoma during pregnancy

2020 ◽  
Vol 98 (3) ◽  
pp. 178-184
Author(s):  
T. V. Chernyakova ◽  
A. Yu. Brezhnev ◽  
I. R. Gazizova ◽  
A. V. Kuroyedov ◽  
A. V. Seleznev
Keyword(s):  
Pregnant Women ◽  
Laser Treatment ◽  
Progressive Disease ◽  
Clinical Course ◽  
The Other ◽  
Third Trimester ◽  
The Third ◽  
Chronic Progressive Disease ◽  
Hypotensive Therapy ◽  
Eye Pressure

In the review we have integrated all up-to-date knowledge concerning clinical course and treatment of glaucoma among pregnant women to help specialists choose a proper policy of treatment for such a complicated group of patients. Glaucoma is a chronic progressive disease. It rarely occurs among childbearing aged women. Nevertheless the probability to manage pregnant patients having glaucoma has been recently increasing. The situation is complicated by the fact that there are no recommendations on how to treat glaucoma among pregnant women. As we know, eye pressure is progressively going down from the first to the third trimester, so we often have to correct hypotensive therapy. Besides, it is necessary to take into account the effect of applied medicines on mother health and evaluate possible teratogenic complications for a fetus. The only medicine against glaucoma which belongs to category B according to FDA classification is brimonidine. Medicines of the other groups should be prescribed with care. Laser treatment or surgery may also be a relevant decision when monitoring patients who are planning pregnancy or just bearing a child. Such treatment should be also accompanied by medicines.

The Nile Delta during the Early Dynastic and Old Kingdom periods. Preliminary remarks on the evolution of settlement landscape

2020 ◽  
pp. 13-61
Author(s):  
Natalia Małecka-Drozd
Keyword(s):  
Nile Delta ◽  
Ancient Egypt ◽  
The Other ◽  
Old Kingdom ◽  
The Third ◽  
Other Hand ◽  
Early Dynastic ◽  
Territorial Structure ◽  
Settlement Landscape ◽  
New Settlements

The 3rd millennium BC appears to be a key period of development of the historical settlement landscape in ancient Egypt. After the unification of the country, the process of disappearance of the predynastic socio-political structures and settlement patterns associated with them significantly accelerated. Old chiefdoms, along with their centres and elites, declined and vanished. On the other hand, new settlements emerging in various parts of the country were often strictly related to the central authorities and formation of the new territorial administration. Not negligible were climatic changes, which influenced the shifting of the ecumene. Although these changes were evolutionary in their nature, some important stages may be recognized. According to data obtained during surveys and excavations, there are a number of sites that were considerably impoverished and/or abandoned before and at the beginning of the Old Kingdom. On the other hand, during the Third and Fourth Dynasties some important Egyptian settlements have emerged in the sources and begun their prosperity. Architectural remains as well as written sources indicate the growing interest of the state in the hierarchy of landscape elements and territorial structure of the country.

Avoiding Shame and Guilt

2018 ◽  
Author(s):  
C. Daniel Batson
Keyword(s):  
Empathic Concern ◽  
The Other ◽  
The Third ◽  
Helping Relationship ◽  
Shame And Guilt

After rejecting the remove–empathy hypothesis (Chapter 4), attention turned to the other two classic egoistic explanations for the motivation to help produced by empathic concern: empathy-specific punishment and empathy-specific reward. This chapter considers two kinds of empathy-specific punishment, shame and guilt. The shame hypothesis claims that we help more when we feel empathic concern because we’re motivated to avoid disapproval and censure from others. The guilt hypothesis says that we’re motivated to avoid self-condemnation for failing to do what we should. Contradicting the shame hypothesis, experiments revealed that even when no one else will know if participants fail to help, empathy still increased helping. Contradicting the guilt hypothesis, participants induced to feel empathy helped more even when provided a good excuse for not helping. Given that neither form of empathy-specific punishment could account for the empathy–helping relationship, our search shifted to the third classic egoistic explanation: pursuing pride.

Sign in / Sign up

Export Citation Format

Share Document