LONG-TERM EFFECTS OF ROW SPACING AND FERTILIZER ON THE PRODUCTIVITY OF RUSSIAN WILD RYEGRASS

1968 ◽  
Vol 48 (1) ◽  
pp. 75-84 ◽  
Author(s):  
T. Lawrence ◽  
D. H. Heinrichs

A study was conducted from 1947 to 1966 to determine the long-term effects of row spacings and applications of ammonium phosphate fertilizer (16–20–0) on the productivity and persistence of Russian wild ryegrass, Elymus junceus Fisch.The optimum row spacing for highest seed production was 0.9 m, whereas for highest forage production it was 0.6 m. The 280-kg/ha rate of fertilizer significantly increased the seed and forage yield over the 151-kg/ha rate, which in turn significantly increased the yield over the zero fertilizer treatment.Increases in precipitation in August and September increased the seed yield of Russian wild ryegrass the following year. Significant positive correlations were found between forage yields and precipitation during March, April, May, and the previous September for practically all treatments.Width of row increased with age of stand. During the 19-year period there was still bare ground between the grass rows seeded 0.9 and 1.2 m apart. These areas of bare ground were slightly narrower when fertilizer was used, indicating that fertilizer application tended to accelerate row-width development.Russian wild ryegrass was found to have excellent cold tolerance, drought tolerance and persistence. It survived through a long drought period and resisted invasion by weeds and volunteer grass seedlings after the third crop year.

2012 ◽  
Vol 40 (2) ◽  
pp. 210 ◽  
Author(s):  
Hamid MADANI ◽  
Mohammad Ali MALBOOBI ◽  
Kioomars BAKHSHKELARESTAGHI ◽  
Agnieszka STOKLOSA

A field experiment was conducted for investigation of different phosphorus fertilizer sources and their importance in rapeseed farms on 2007 at Arak, Iran. Ammonium phosphate fertilizer with 50% P2O5 (APF) was as chemical phosphorus sources with 3 rates of application and Phosphor solublizing bacteria (PSB) was as biological phosphorus surcease in 4 levels. Experiment was factorial arrangement in randomized complete block design with 3 replications. APF levels were control (AP0), 125kg/ha APF (AP1) and 250kg/ha (AP2) application and PSB levels were, control (PSB0), PSB at sowing time only (PSB1), PSB as top dress fertilizer after over wintering only (PSB2) and PSB at dual fertilizing in sowing time and also after over wintering (PSB3). The statistical analyses were showed that the PSB3 treatment was a great treatment for increasing seed yield. The heist rate of seed yield was recorded at 9.9t/ha under dual fertilizing in sowing time and after rosette over wintering stage. The interaction effects of phosphorus solublizing bacteria and ammonium phosphate fertilizer application had not significant effect on plant height, biomass yield, number of silique per plant, seed oil percent and seed yield. Interaction effects of phosphorus solublizing bacteria and ammonium phosphate fertilizer application were significant for plant tissues phosphorus content.


2000 ◽  
Vol 36 (2) ◽  
pp. 205-221 ◽  
Author(s):  
T. J. REGO ◽  
V. NAGESWARA RAO

In southern and central India, farmers crop Vertisols only in the post-rainy season, to avoid land management problems in the rainy season. In 1983 ICRISAT established a long-term trial seeking to intensify cropping. The trial included intercrops, sequential crops and appropriate Vertisol management technology to allow consecutive rainy-season and post-rainy season crops to be grown. Benefits provided by legumes to succeeding rainy-season sorghum (Sorghum bicolor) were analysed in relation to a non-legume system of sorghum + safflower (Carthamus tinctorius). Rainy-season sorghum grain yield production was sustained at about 2.7 t ha−1 over 12 years within a continuous sorghum–pigeonpea (Cajanus cajan) intercrop system. With a cowpea–pigeonpea intercrop system, succeeding sorghum benefitted each year by about 40 kg N ha−1 (fertilizer nitrogen (N) equivalent). Without N fertilizer application the sorghum grain yield was around 3.3 t ha−1. Legume benefits were less marked in the chickpea (Cicer arietinum)-based rotation than in the pigeonpea system, in which a 12-year build up of soil total N (about 125 μg g−1) was observed. Although sorghum benefitted from this system, pigeonpea yields declined over time due to soil-borne fungi and nematodes. Wider rotations of crops with pigeonpea may help to overcome these problems, while sustaining sorghum production.


1983 ◽  
Vol 63 (2) ◽  
pp. 443-452 ◽  
Author(s):  
GILLES DEPUIS

The effect of companion crop management on the establishment of alfalfa was evaluated. The studied variables included species of cereals, row spacing and seeding rate of companion crop, stage of maturity of the companion crop at harvest, and an additional nitrogen fertilizer application. The cereals were harvested as forage. In the year after the seeding year, the first yield of alfalfa was determined. In seven trials, forage yields of a pure stand of alfalfa were 3350 kg/ha in the first cut of the seeding year. These yields averaged 60% of forage yields obtained from the combination of alfalfa and companion crop. However, cereals substantially reduced the total digestible nutrients, crude protein and calcium contents of the forage as compared to the pure alfalfa. The additional 38 kg/ha of nitrogen at tillering provided an extra yield of 600 kg/ha. Row spacing had little or no effect on forage yield. Even though wider spacings has considerably reduced seeding rates increased spacing from 18 to 54 cm did not affect barley yield while wheat was reduced by 400 kg/ha and oat increased by 300 kg/ha. Also, the average number of stems per meter of row increased by 89% with an average weight gain of 23% for each stem at the 54-cm spacing. At the first cut in the year following establishment, yields of alfalfa established with a companion crop were equal to or lower than those in pure stand. Yield reductions varied from 0 to 13% with barley and wheat but approached 30% when oats were seeded in 18-cm rows. However, the yield reduction was only 14% in the 54-cm row spacing of oats.Key words: Medicago sativa L., nitrogen fertilization, companion crop


1982 ◽  
Vol 62 (3) ◽  
pp. 741-750 ◽  
Author(s):  
LARRY HUME

The effect of fertilizer application and three rotations (continuous cropping, fallow-wheat, and fallow-wheat-wheat rotations) on the species composition of the weed community was examined using rotations that had been running for 21–22 yr at Indian Head, Saskatchewan. Before spring seeding, stinkweed and lamb’s-quarters were more abundant on wheat after fallow than they were on either wheat following wheat after fallow or on continuous cropping. After seeding, continuous cropping produced the largest weed densities of green foxtail, thyme-leaved spurge, and vetch. In most instances, Canada thistle was most abundant on continuously cropped and nonfertilized plots. After spring seeding, green foxtail was the only species with a larger density on fertilized plots. Interactions between fertilizer application and rotation, and among species, influenced species composition in the weed community. Fertilizer application tended to reduce community differences between continuous cropping and short-term wheat-fallow rotations. Allelopathic effects of Canada thistle may have reduced green foxtail and redroot pigweed densities. With the use of 2-or 3-yr wheat-fallow rotations and herbicide application, weed problems can be minimized in southeastern Saskatchewan.


2002 ◽  
Vol 82 (1) ◽  
pp. 67-74
Author(s):  
A. J. Leyshon ◽  
P. G. Jefferson ◽  
J. Waddington

Widely seeded rows (>60 cm) of perennial grasses have exhibited greater long-term yield stability, but allow weed invasion in the first years after establishment. A 9-yr study was conducted at a semiarid site at Swift Current, Saskatchewan, Canada, to determine the effects of intercropping oats (Avena sativa L.) and slender wheatgrass [Elymus trachycaulus (Link) Gould ex Shinners] between rows of Russian wildrye [Psathyrostachys juncea (Fisch.) Nevski], and Altai wildrye [Leymus angustus (Trin) Pilger] seeded in 90-cm spacings either alone or in alternate rows with alfalfa (Medicago sativa L.). Two rows of oats depressed grass forage production in the year following establishment. Slender wheatgrass intercrops reduced grass forage yield and alfalfa forage yield. However, slender wheatgrass contributed to increased total forage yields while it persisted in the mixture. By the fifth year, it had disappeared from the Russian wildrye plots but persisted 2 more years when intercropped with Altai wildrye. Interseeded companion crops, either annual or short-lived perennials, for forage will give short-term yield gains, but long-lived perennial forages may not recover from the competition in the long-term. Key words: Avena sativa, Elymus trachycaulus, Psathyrostachys juncea, Leymus angustus, Medicago sativa, forage yield


Agronomy ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 353 ◽  
Author(s):  
Xu-Peng Zeng ◽  
Kai Zhu ◽  
Jian-Ming Lu ◽  
Yuan Jiang ◽  
Li-Tao Yang ◽  
...  

Nitrogen (N) plays an important role in sugarcane (Saccharum spp. hybrids) growth and development; however, long-term effects of N application levels on cane and sugar production in different sugarcane cultivars under field conditions remain unclear. In this study, we investigate the agronomic, yield, and quality traits in three sugarcane cultivars (GT11, B9, and ROC22) under different N levels (0, 150, and 300 kg/ha urea) from 2015 to 2019. Continuous four-year field experiments of plant and ratoon crops were carried out by using two-factor split-plot design. The results showed that N fertilizer application improved the tillering rate, stalk diameter, plant height, stalk weight, millable stalks/ha, cane yield, sugar yield and juice rate of cane, and the difference between N application and non-N application was significant. The cane yield, millable stalks/ha, juice rate, and juice gravity purity increased with the increase of N application, but the milled juice brix and sucrose % cane decreased with the increase of N application. The sugar yield was the highest at 150 kg/ha urea application, while the cane yield was the highest at 300 kg/ha urea application. Different N fertilizer application levels significantly regulated the activities of glutamic pyruvic transaminase (GPT) and glutamic oxaloacetic transaminase (GOT) and the contents of chlorophyll and nitrate N in plant leaves, which reflected the regulation in nitrogen metabolism and alteration in dry matter production and distribution, cane yield and sugar accumulation in different sugarcane cultivars. During the four-year experiment duration, the cane yield and sugar yield generally showed ROC22 > B9 > GT11. These data suggested that 300 kg/ha urea application was suitable for the plant and first ratoon crops, and 150 kg/ha urea application was suitable for the second and third ratoon crops. Both cane and sugar yields could be the highest in a four-year production cycle under this circumstance.


2016 ◽  
Vol 13 (18) ◽  
pp. 5221-5244 ◽  
Author(s):  
Arne Poyda ◽  
Thorsten Reinsch ◽  
Christof Kluß ◽  
Ralf Loges ◽  
Friedhelm Taube

Abstract. A large share of peatlands in northwestern Germany is drained for agricultural purposes, thereby emitting high amounts of greenhouse gases (GHGs). In order to quantify the climatic impact of fen soils in dairy farming systems of northern Germany, GHG exchange and forage yield were determined on four experimental sites which differed in terms of management and drainage intensity: (a) rewetted and unutilized grassland (UG), (b) intensive and wet grassland (GW), (c) intensive and moist grassland (GM) and (d) arable forage cropping (AR). Net ecosystem exchange (NEE) of CO2 and fluxes of CH4 and N2O were measured using closed manual chambers. CH4 fluxes were significantly affected by groundwater level (GWL) and soil temperature, whereas N2O fluxes showed a significant relation to the amount of nitrate in top soil. Annual balances of all three gases, as well as the global warming potential (GWP), were significantly correlated to mean annual GWL. A 2-year mean GWP, combined from CO2–C eq. of NEE, CH4 and N2O emissions, as well as C input (slurry) and C output (harvest), was 3.8, 11.7, 17.7 and 17.3 Mg CO2–C eq. ha−1 a−1 for sites UG, GW, GM and AR, respectively (standard error (SE) 2.8, 1.2, 1.8, 2.6). Yield-related emissions for the three agricultural sites were 201, 248 and 269 kg CO2–C eq. (GJ net energy lactation; NEL)−1 for sites GW, GM and AR, respectively (SE 17, 9, 19). The carbon footprint of agricultural commodities grown on fen soils depended on long-term drainage intensity rather than type of management, but management and climate strongly influenced interannual on-site variability. However, arable forage production revealed a high uncertainty of yield and therefore was an unsuitable land use option. Lowest yield-related GHG emissions were achieved by a three-cut system of productive grassland swards in combination with a high GWL (long-term mean  ≤  20 cm below the surface).


Sign in / Sign up

Export Citation Format

Share Document