Nitrogen fixation and transfer by some tropical and temperate pasture legumes in sand culture

1962 ◽  
Vol 2 (6) ◽  
pp. 132 ◽  
Author(s):  
EF Henzell
Keyword(s):  
Nitrogen Fixation ◽  
White Clover ◽  
Sand Culture ◽  
Tropical Species ◽  
First Year ◽  
Pasture Legumes ◽  
Total Fixation ◽  
Nitrogen Donor ◽  
Second Year ◽  
Indigofera Spicata

Nitrogen fixation by four tropical pasture legumes-Indigofera spicata Forsk., Desmodium uncinatum (Jacq.) D.C., Lotononis bainesii Bak., and Stylosanthes bojeri Vogel-and by lucerne (Medicago sativa L.) and white clover (Trifolium repens L.), was measured in sand culturere in the glasshouse. During a two year period lucerne and white clover fixed significantly more nitrogen than any of the tropical species. Indigofera spicata fixed as much nitrogen as lucerne during the first year, but was only half as productive as lucerne during the second year. Lotononis bainesii added as much nitrogen as Indigofera spicata, while smaller amounts were fixed by Desmodium uncinatum and Stylosanthes bojeri. It is likely that nitrogen fixation by Lotononis bainesii, Desmodium uncinatum, and Stylosanthes bojeri was restricted by strains of Rhizobium that were not fully effective. Paspalum commersonii Lam. was grown in association with four of the legumes. White clover was the most efficient nitrogen donor in the first year and Desmodium uncinatum was superior to the other legumes during the second year. The proportion of nitrogen transferred to the grass over two years was only 0.6 to 1.7 per cent of total fixation. Some possible reasons for this result are discussed.

NEW CLOVER CULTIVARS FOR WAIKATO DAIRY PASTURE: ESTABLISHMENT, PRODUCTION AND NITROGEN FIXATION DURING THE FIRST YEAR

1988 ◽  
pp. 207-211
Author(s):  
S.F. Ledgard ◽  
G.J. Brier ◽  
R.N. Watson
Keyword(s):  
Nitrogen Fixation ◽  
White Clover ◽  
Dairy Cow ◽  
Red Clover ◽  
First Year ◽  
Buried Seed

Clover cultivars grown with ryegrass were compared in an establishment year under dairy cow grazing. There was no difference in total annual productton but summer production was greater with Pawera red clover and with Kopu or Pitau white clovers. Clovers differed little in the proportion of nitrogen fixed, except during summer when values were highest for Pawera. Pawera was less prone to nematode attack than white clover cultivars but was more susceptible to clover rot. Resident clovers and high buried seed levels (e.g., 11-91 kg/ha) made introduction of new clover cultivars difficult. Sown clovers established best (50-70% of total clover plants) when drilled into soil treated with dicamba and glyphosate. Keywords: white clover, red clover, nematodes. nitrogen fixation, pasture renovation

scholarly journals The key to successful second year white clover seed crops

1996 ◽  
Vol 6 ◽  
pp. 40-40
Author(s):  
B.L. Mccloy ◽  
S.R. White
Keyword(s):  
Seed Yield ◽  
White Clover ◽  
Block Design ◽  
First Year ◽  
Flower Number ◽  
Mature Flower ◽  
Second Year ◽  
Clover Seed ◽  
Seed Crops ◽  
Rotary Type

In recent years there has been an increase in the number of white clover seed crops taken for a second harvest. Traditionally yields from second year crops are substantially lower than first year crops. A trial was established investigating techniques to increase yields in second year crops. The trial was located in a dryland crop of white clover (cv. Grasslands Demand) 4 km east of Methven, mid Canterbury. It involved 10 herbicide treatments and 8 'inter-row' treatments arranged in a split block design. Number of mature flower heads were recorded on all treatments at harvest as an indirect estimate of yield. Additionally, selected treatments were cut and collected using a rotary type mower, threshed, and machine dressed for direct estimates of seed yield. Flower number and machine dressed seed yield were significantly (P

Resistance of New Zealand dairy pastures to ingress of summer-active annual grass weeds

2012 ◽  
Vol 63 (10) ◽  
pp. 1026 ◽  
Author(s):  
K. N. Tozer ◽  
E. Minneé ◽  
C. A. Cameron
Keyword(s):  
Perennial Ryegrass ◽  
White Clover ◽  
Tall Fescue ◽  
Festuca Arundinacea ◽  
Control Measures ◽  
First Year ◽  
Similar Distribution ◽  
Annual Grass ◽  
Bare Ground ◽  
Second Year

Yellow bristle grass (Setaria pumila) and summer grass (Digitaria sanguinalis) are summer-active annual grass weeds which infest temperate dairy pastures. A study was undertaken over 2 years to compare hand-sown yellow bristle and summer grass establishment, survival, and seed production in pastures grazed by dairy cows and based on (i) tetraploid perennial ryegrass (Lolium perenne), (ii) tetraploid perennial ryegrass and white clover (Trifolium repens), and (iii) tall fescue (Festuca arundinacea) and white clover, to determine which pasture type offered the greatest resistance to these grass weeds. Ingress of grass weeds was similar in all three pasture types. Total dry matter production was similar for all pasture types for the first year and lower in tall fescue + clover than perennial ryegrass pasture in the second year. All pasture types had a similar distribution of microsite types (bare ground ± canopy, basal cover ± canopy) in both years. The annual grass weeds were most prevalent in bare ground + canopy microsites, which were also the most frequent of the four microsite types. In the first year, <5% of microsites were occupied within 2 months of sowing, whereas in the second year, microsite occupation remained >13% for all assessments. In the first year, panicle production of yellow bristle and summer grass was similar (averaging 4.1 panicles plant–1); in the second year, panicle production was greater for summer grass (0.80 v. 0.16 panicles plant–1, respectively). Where present, these annual grass weeds are likely to spread in dryland dairy pastures sown with either perennial ryegrass or tall fescue. Variability in their panicle production between years shows how their impact on pasture performance and consequent need for control measures will also vary from year to year.

scholarly journals Nitrogen Fixation and Nutritional Yield of Cowpea-Amaranth Intercrop

Agronomy ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 565
Author(s):  
Buhlebelive Mndzebele ◽  
Bhekumthetho Ncube ◽  
Melvin Nyathi ◽  
Sheku Alfred Kanu ◽  
Melake Fessehazion ◽  
...  
Keyword(s):  
Nitrogen Fixation ◽  
Rural Communities ◽  
Soil Nutrient ◽  
Micronutrient Deficiency ◽  
Sub Saharan Africa ◽  
First Year ◽  
Iron And Zinc ◽  
Second Year ◽  
Sub Saharan ◽  
Phosphorus And Potassium

Nutrient-poor soils coupled with micronutrient deficiency among many rural resource-poor communities remain a challenge in sub-Saharan Africa. Nutrient-poor soils can be managed through various soil amendment or fertilisation strategies. Micronutrients can be supplied through plants. The study was aimed at determining the symbiotic nitrogen fixation of cowpea as well as the contribution of inter-cropping under varying levels of nitrogen, phosphorus, and potassium (NPK) fertilisation. In addition, the amount of micronutrients supplied by cowpea and amaranth were determined. The experiment was laid out in a 2 × 4 factorial treatment structure in a completely randomised design, with inter-cropping (cowpea and amaranth) and fertiliser (control, 25%, 50%, and 100% of the recommended NPK levels) as treatment factors with four replications. Symbiotic N2 fixation of cowpea decreased from 341–448 kgN.ha−1 to 77–91 kgN.ha−1 for the first year and 557–227 kgN.ha−1 to 92−164 kgN.ha−1 for the second year with fertilisation. The iron and zinc nutritional yield increased (61–210 g.ha−1 for first year and 304–867 g.ha−1, for second year), proportional to fertiliser application to both crops. The research shows the benefits of leguminous crops in soil nutrient fertility and inorganic fertilisation with inter-cropping in managing micronutrient deficiency to meet the nutritional needs of rural communities.

The productivity of irrigated legumes in northern Victoria. 2. Effect of grazing management

2005 ◽  
Vol 45 (12) ◽  
pp. 1577 ◽  
Author(s):  
K. B. Kelly ◽  
C .R. Stockdale ◽  
W. K. Mason
Keyword(s):  
Leaf Area ◽  
White Clover ◽  
Growth Rates ◽  
Carbon Balance ◽  
Red Clover ◽  
Subterranean Clover ◽  
Net Photosynthesis ◽  
First Year ◽  
Second Year ◽  
Persian Clover

The productivity of irrigated white (Trifolium repens L.) and red (Trifolium pratense L.) clover swards was compared in an experiment of more than 3 years duration. It was hypothesised that white clover would be more productive than red clover when defoliation was frequent and intense, and less productive when defoliation was infrequent and lax. The experiment was a factorial design involving 2 species of clover [white clover (cv. Haifa) and red clover (cv. Redquin)], 2 grazing frequencies and 2 grazing intensities (with the criteria for both being based on quantities of herbage present before/after grazing). There were 4 extra treatments sown: perennial ryegrass (Lolium perenne L. cv. Grasslands Nui) and white clover (cv. Haifa), lucerne (Medicago sativa L. cv. Validor), Persian clover (Trifolium resupinatum L. cv. Maral) or subterranean clover (Trifolium subterraneum L. cv. Trikkala), but only 1 defoliation treatment was used for each of these treatemnts. There were 4 replicated blocks of all treatments. Apparent growth rates [calculated from measurements of dry matter (DM) removed by grazing] of white clover ranged from a low of 10 kg DM/ha.day in winter to a high of 70 kg DM/ha.day in summer. The growth rates of white clover swards were superior to those of ryegrass and white clover swards over summer, but were generally lower from May to October. In 2 of the 4 years, frequent grazing of white clover resulted in greater (P<0.05) production than infrequent grazing (average of 12.8 v. 10.7 t DM/ha) whereas intensity of grazing only affected DM net accumulation in the first year (P<0.05). The data show no evidence of a decline in productivity over time. Sward structure of white clover was influenced by grazing treatment with the numerically highest yielding treatment (frequent and hard) having the highest density of stolon tips (vegetative buds). In relation to days of regrowth, the frequently grazed treatment had higher levels of net photosynthesis in spring and summer compared with the infrequently grazed treatment. The frequently grazed treatment achieved positive carbon balance immediately after grazing and reached maximum levels of photosynthesis at 8–10 days, whereas the infrequent treatment showed negative carbon balance for the first 2–3 days after grazing with maximum photosynthesis being achieved later than in the frequently grazed treatment. When net photosynthesis was related to leaf area, there were fewer differences between the 2 treatments. The exception was in spring when photosynthesis was lowest where the initial leaf area was highest in the infrequent and hard treatment. Maximum photosynthesis was achieved at diminishing leaf area index from spring through to winter. Red clover was the most productive legume in the first year after establishment, but it did not persist beyond the second year and its DM net accumulation was reduced by more frequent grazing (12.4 v. 15.3 t DM/ha in the first year and 6.1 v. 9.1 t DM/ha in the second year; P<0.05). The DM net accumulation of lucerne was greater than that in any other treatment (an average of 16.7 t DM/ha in the 2 completed years), whereas the annual legumes, subterranean clover and Persian clover, averaged 6.6 and 10.7 t DM/ha.year, respectively. The seasonal growth rate data showed that lucerne had very good summer production whereas the annuals tended to be at least as good as the perennials from May to October.

scholarly journals Weed Spread and Caraway (Carum carvi L.) Crop Productivity in a Multi-Cropping System

Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1172
Author(s):  
Aušra Marcinkevičienė ◽  
Aušra Rudinskienė ◽  
Rimantas Velička ◽  
Robertas Kosteckas ◽  
Zita Kriaučiūnienė
Keyword(s):  
Spring Wheat ◽  
White Clover ◽  
Spring Barley ◽  
Cropping System ◽  
Crop Productivity ◽  
First Year ◽  
The Third ◽  
Perennial Weeds ◽  
Second Year ◽  
Vegetative Season

The field experiment was carried out at the Experimental Station of Vytautas Magnus University Agriculture Academy (Lithuania) in 2017–2019. The aim of the study was to determine and to compare weed spread and caraway crop productivity in sole (spring barley, spring wheat, pea, caraway), binary (spring barley-caraway, spring wheat-caraway, pea-caraway) and trinary (spring barley-caraway-white clover, spring wheat-caraway-white clover, pea-caraway-white clover) crops. In the second and the third years of caraway cultivation, it was estimated that the abundance of perennial weeds in the crops increased. In the first year, significantly the highest dry matter mass of weeds was determined in non-sprayed with herbicides binary crops with undersown caraway and in trinary crops with undersown caraway and clover; in the second year—in the caraway binary crops, when they were grown after barley and wheat without clover; in the third year—in caraway binary and trinary crops when they were grown after barley, wheat and pea without clover and after barley and wheat with clover. In the second year, the highest yields of caraway seeds were obtained by growing them in peas, and in the third year by growing them in wheat together with clover. Caraway can be grown in trinary crops, including white clover, and harvested in the second or the third year of the vegetative season.

An inevitable crisis? From first to second year in counsellor training

2020 ◽  
Vol 5 (1) ◽  
pp. 74-89
Author(s):  
Hugh Crago
Keyword(s):  
Right Hemisphere ◽  
Training Programme ◽  
First Year ◽  
Training Experience ◽  
Counsellor Training ◽  
Student Dropout ◽  
Second Year ◽  
Neurological Research ◽  
First Year Of Life ◽  
And Control

In a seminal 1973 paper, Robert Clark described the very different “cultures” of the first and second year students in a four year clinical psychology PhD programme. The author applies Clark’s template to his own experiences as trainee or trainer in five different counsellor education programmes, one in the US and four in Australia. Each of the programmes, to varying degrees, demonstrates key features of the pattern identified by Clark, where the first year is “therapeutic” and other-oriented, the second is “professional” and self-focused. The author concludes that all the surveyed programmes exhibited some level of “second year crisis”, in which a significant number of students felt abandoned, dissatisfied, or rebellious. The author extends and refines Clark’s developmental analogy (first year = childhood; second year = adolescence) to reflect recent neurological research, in particular, the shift from a right hemisphere-dominant first year of life, prioritising affiliative needs, to a left hemisphere-dominant second year, prioritising autonomy and control. This shift is paralleled later by a more gradual move from a protective, supportive childhood to necessary, but sometimes conflictual, individuation in adolescence. The first two years of a counsellor training programme broadly echo this process, a process exacerbated by the second year internship/placement, in which students must “leave home” and adjust to unfamiliar, potentially less nurturing, authority figures. Finally, the author suggests introducing more rigorous “academic holding” into the first year, and greater attention to “therapeutic holding” of dissident students in the second, hopefully decreasing student dropout, and achieving a better balanced training experience.

Implementation of the Second-year course in an Engineering Professional Spine

2018 ◽  
Author(s):  
Umar Iqbal ◽  
Deena Salem ◽  
David Strong
Keyword(s):  
Learning Outcomes ◽  
Research University ◽  
Engineering Students ◽  
Employability Skills ◽  
First Year ◽  
Computer Engineering ◽  
Core Courses ◽  
Second Year ◽  
First Time ◽  
Academic Year

The objective of this paper is to document the experience of developing and implementing a second-year course in an engineering professional spine that was developed in a first-tier research university and relies on project-based core courses. The main objective of this spine is to develop the students’ cognitive and employability skills that will allow them to stand out from the crowd of other engineering graduates.The spine was developed and delivered for the first time in the academic year 2010-2011 for first-year general engineering students. In the year 2011-2012, those students joined different programs, and accordingly the second-year course was tailored to align with the different programs’ learning outcomes. This paper discusses the development and implementation of the course in the Electrical and Computer Engineering (ECE) department.

Exploring the Implementation of Early Math Assessments in Kindergarten Classrooms: A Research-Practice Collaboration

2020 ◽  
Author(s):  
Jennifer McDonald ◽  
Rebecca Merkley ◽  
Jacqueline Mickle ◽  
Lisa Collimore ◽  
Daniel Ansari
Keyword(s):  
Mathematical Thinking ◽  
Math Education ◽  
Kindergarten Students ◽  
First Year ◽  
Research Practice ◽  
Early Numeracy ◽  
Future Directions ◽  
Collaborative Project ◽  
Practice Gap ◽  
Second Year

Research in cognitive development has highlighted that early numeracy skills are associated with later math achievement, suggesting that these skills should be targeted in early math education. Here we tested whether tools used by researchers to assess mathematical thinking could be useful in the classroom. This paper describes a collaborative project between cognitive scientists and school board researchers/educators implementing numeracy screeners with kindergarten students over the course of three school years. The Give-A-Number task (Wynn, 1990) was used with first-year kindergarten students and the Numeracy Screener [BLINDED] with second-year kindergarten students. Results indicated that educators (N = 59) found the tools feasible to implement and helpful for exploring their students’ thinking and targeting instruction. The Educators’ feedback also helped inform improvements to the implementation of the tools and future directions for both the schools and the researchers. This work emphasizes the importance of transdisciplinary collaboration to address the research-practice gap.

Influence of abiotic factors and hosts on seasonal dynamic of green lacewing, Chrysoperla carnea (Stephens)

2016 ◽  
Vol 3 (3) ◽  
Author(s):  
ARVIND KUMAR ◽  
POOJA KHULBE
Keyword(s):  
Abiotic Factors ◽  
Host Population ◽  
Maximum Temperature ◽  
First Year ◽  
Green Lacewing ◽  
Larval Population ◽  
Correlation Studies ◽  
Helianthus Annus ◽  
Sunflower Crop ◽  
Second Year

Influence of abiotic factors and hosts on population dynamics of green lacewing, Chrysoper lacarnea (Stephens) was studied in sunflower, Helianthus annus (Linn.).The maximum number of C. carnea population was found during mid March –mid April in the first year and mid April – mid May in the second year in sunflower crop. The maximum number of host population viz. egg and larva of Helicoverpa armigera and Myzuspe rsicae population were found during mid March –mid April in both the year and correlation studies revealed the positive and significant correlation between larval population of H. armigera, M. persicae and predator C. carnea. While there was no significant relationship found between eggs of H. armigera and C. carnea. The C. carnea population on H. annus during both the year was positively correlated with maximum temperature and found significant,while negatively correlated with relative humidity.However, no significant correlation of C. carnea was found with minimum temperature in both the year.

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