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Приведены основные результаты селекции сортов многолетних трав с фитоценотической устойчивостью и совместимостью в многови...
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Приведены основные результаты селекции сортов многолетних трав с фитоценотической устойчивостью и совместимостью в многовидовых посевах на пойменных и полевых землях степной части Центрально-Чернозёмного региона.
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Приведены основные результаты работы станции по селекции многолетних трав. Воронежская опытная станция по многолетним трава...
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Приведены основные результаты работы станции по селекции многолетних трав. Воронежская опытная станция по многолетним травам создана в1920 году как Павловская луговая опытная станция. В1935 году она была реорганизована в Павловское опытное поле по луговодству, входящее в состав НИИ сельского хозяйства ЦЧП им. Докучаева.
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Western salsify has recently formed dense stands in Conservation Reserve Program (CRP) lands in north-central Montana. Our objective was to test the effects of various herbicide treatments and mowing on western salsify and associa...
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Western salsify has recently formed dense stands in Conservation Reserve Program (CRP) lands in north-central Montana. Our objective was to test the effects of various herbicide treatments and mowing on western salsify and associated vegetation in CRP lands. Six herbicide treatments and one mowing treatment were applied at three sites in 2010. Herbicide treatments included combinations of glyphosate, 2,4-D, dicamba, and/or metsulfuron-methyl applied when western salsify was either in the rosette or early flowering stage. Mowing was applied at the early flowering stage. Herbicide treatments reduced western salsify and increased perennial grass at one of the three sites, which was the site most dominated by western salsify. When dicamba (0.14 kg ae ha-1) plus 2,4-D (0.48 kg ae ha-1) was applied at the rosette stage, western salsify adult plant density and biomass were reduced to zero and perennial grass biomass increased by 108% in 2010. In 2011, western salsify adult plant density was lower across all herbicide treatments compared to the mowed and nontreated plots. Annual grass density increased by up to 400% when herbicide applications including metsulfuron-methyl were applied at the early flowering stage. Mowing did not control western salsify. Results suggest dicamba plus 2,4-D applied at the rosette stage can provide effective control of western salsify and increase perennial grasses without stimulating the emergence of annual grasses.
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Spartina argentinensis, Panicum prionitis, and Arundo donax are perennial grasses and Geoffroea decorticans is a shrub, all
of which grow under adverse conditions in the Litoral region in Argentina. The pyrolytic conversion of th...
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Spartina argentinensis, Panicum prionitis, and Arundo donax are perennial grasses and Geoffroea decorticans is a shrub, all
of which grow under adverse conditions in the Litoral region in Argentina. The pyrolytic conversion of these biomasses
was studied at 550 ℃ in a fixed bed reactor during 30 min under N_2 flow with a 20 ℃ min~(−1) heating ramp starting at room
temperature. The main products were liquid, two phases (aqueous and oil) being observed with the aqueous phases
being the most important in all the cases (yields from 29.2 to 45.7 wt%). The highest yield for an oil phase (18 wt%) was
observed with the shrub and the yield of gases and chars were similar in all the cases. By means of sequential vacuum
distillation I was possible to selectively separate water, methanol and acetic acid which were present in the aqueous
phases, thus increasing the concentration of high value compounds such as ketones, phenols and furans in the residual
fraction. The concentration of phenolic compounds in the residual fraction was 60% higher than the initial one in the
aqueous phase. The oil phase mainly contained phenols, ketones and acids with high molecular weight. According to
these results, these biomasses can be considered as a source of energy, fuels or chemicals, and it is possible to propose
a methodology to upgrade the aqueous fractions in pyrolysis liquids.
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Biomass production and plant quality vary between plant species and morphological components of a plant. The purpose of this two-part experiment was (1) to study the influence of energycane [Saccharum sp. (L.) 'US 72-1153'] harves...
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Biomass production and plant quality vary between plant species and morphological components of a plant. The purpose of this two-part experiment was (1) to study the influence of energycane [Saccharum sp. (L.) 'US 72-1153'] harvest treatments (6) on dry biomass yield and (2) monitor changes in quantity and quality of plant components with increased plant height. Treatments for Part 1 determined the influence of plant height when harvested at 1.2, 2.5, and 3.7 m, mature stage in October (4.9 m, in flower), mature stage in December (4.9 m, in flower), and additional treatment harvested in October, which received half the total N (168 kg ha~(-1)) on dry biomass yield from 1986 to 1989. Part 2 treatments were to monitor changes in quantity and quality (crude protein and in vitro organic matter digestion) of plant components (green leaf, dead leaf, and stem) at 0.6 m plant height increments to a final height of 4.3 m during 1986 and 1987. Treatments from both parts of the study received 25 kg P ha~(-1) and 93 kg K ha~(-1) in one application and 336 kg N ha~(-1) yr~(-1) in single or split applications applied prior to growth of each harvest. Plants repeatedly harvested at the 1.2 m height (Part 1) and mature stage produced a 4-year average yield of 10 and 48 Mg ha~(-1) yr~(-1) dry biomass, respectively and decreased in dry biomass yield 89% (1.2 m harvest) and 53% (mature harvest) between years 1 and 4. The stem (1986 and 1987) and dead leaf (1986) plant components increased quadratically as plant height increased, and green leaf decreased from 70% (0.6 m) to 17% (4.3 m height). The crude protein concentration decreased 51% (green leaf) and 81% (stem) and in-vitro organic matter digestion decreased 54, 32, and 34% for dead leaf, green leaf, and stem, respectively as plant height increased from 0.6 to 4.3 m. These data indicate that harvest management is an important factor for energycane biomass yield, ratoon-crop success and plant quality if biomass is used as a methane source.
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Oxalate may cause hypocalcaemia or formation of urinary calculi in animals with prolonged grazing of Napier grass (Pennisetum purpureum) x pearl millet (bajra, P. glaucum) hybrid (NBH). We investigated the influence of nitrate met...
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Oxalate may cause hypocalcaemia or formation of urinary calculi in animals with prolonged grazing of Napier grass (Pennisetum purpureum) x pearl millet (bajra, P. glaucum) hybrid (NBH). We investigated the influence of nitrate metabolism, nitrogen (N) nutrition, N forms and seasonal variation on oxalate accumulation in leaves of NBH in a field experiment in Ludhiana, India. The experiment was a randomised block design with three N sources (nitrate, amide and ammonium), three application rates (50, 75 and 100 kg N/ha), four seasons (summer, monsoon, autumn, pre-winter) and three replicates. Applied N nutrition induced oxalate synthesis and activities of nitrate reductase (NR) and nitrite reductase (NiR) enzymes. A positive association of N nutrition with both oxalate accumulation and nitrate-reducing enzymes was found. Nitrate-N increased oxalate accumulation and NiR activity more than ammonium and amide. A differential effect of seasons on NR and NiR activities, as well as on oxalate accumulation, was observed. Among different harvest seasons, NR and NiR activities were positively associated with oxalate accumulation in summer and the monsoon season. These results suggest that N fertilisation, particularly in nitrate form, is associated with upregulation of nitrate-reducing enzymes, leading to oxalate accumulation in NBH leaves.
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Great Plant Picks, the new plant awards program sponsored by the Elisabeth C Miller Botanical Garden in Seattle, has endorsed almost sixty-five plants for 2002. The tree and shrub selections were discussed in the previous issue of...
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Great Plant Picks, the new plant awards program sponsored by the Elisabeth C Miller Botanical Garden in Seattle, has endorsed almost sixty-five plants for 2002. The tree and shrub selections were discussed in the previous issue of Pacific Horticulture (January 2002). The majority of the winners this year are in the perennial and bulb category. The perennial and bulb selection committee, chaired by Alex LaVilla of Swansons Nursery in Seattle, is an enthusiastic group of specialty growers and nurserystaff with a passion for excellence and horticultural variety.
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The conversion of California grasslands from a system dominated by perennial bunchgrasses to one dominated by exotic annual grasses is recognized as an ecologically significant biological invasion (D'Antonio and Vitousek 1992). Th...
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The conversion of California grasslands from a system dominated by perennial bunchgrasses to one dominated by exotic annual grasses is recognized as an ecologically significant biological invasion (D'Antonio and Vitousek 1992). The invasion by exotic annual grasses has drastically altered ecological structure and functional processes through the competitive suppression of native grass seedlings and adults, altering community response to disturbance, and causing changes in soil carbon, other soil nutrients, soil microbes, and soil water profiles (Holmes and Rice 1996, D'Antonio et al. 2007, Koteen et al. 2011).
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Sheep and hair fescue are perennial, tuft forming grasses that spread by seed and form dense sods in wild blueberry fields. These sods compete with the crop for resources and hinder harvest. Field and greenhouse studies were condu...
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Sheep and hair fescue are perennial, tuft forming grasses that spread by seed and form dense sods in wild blueberry fields. These sods compete with the crop for resources and hinder harvest. Field and greenhouse studies were conducted in 2015 to evaluate 1) the effect of sequential glufosinate and foram-sulfuron applications on suppression of fescues in the greenhouse and field, and 2) efficacy of glufosinate and foramsulfuron on fescue seedlings when applied at 2, 4, 6, and 8 wk after seedling emergence in the greenhouse. Glufosinate applications at 750 and 1,005 g ai ha(-1) followed by foramsulfuron application at 35 g ai ha(-)(1) reduced fescue leaf number and biomass relative to foramsulfuron application alone in the greenhouse. In the field study, fescue flowering tuft density, tuft inflorescence height, seed production, and seed viability were reduced by foramsulfuron alone, but there was a trend towards lower seed production and tuft height when fescues were treated with glufosinate at 1,005 g ha(-1) followed by foramsulfuron. Foramsulfuron caused low seedling mortality at all application timings evaluated, but glufosinate caused >90% mortality in seedlings when applied at 2, 4, 6, or 8 wk after seedling emergence. Our results suggest that sequential applications of these herbicides are less effective under field conditions relative to results obtained in the greenhouse, though burndown glufosinate applications may have a role in reducing fescue seedling recruitment. Additional research should be conducted to determine the effect of early spring and autumn glufosinate applications on fescue seedling recruitment and suppression of established fescue tufts with subsequent foramsulfuron applications.
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The ecological integrity of the Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle and A. Young) alliance is being severely interrupted by post-fire invasion of non-native annual grasses. To curtail this in...
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The ecological integrity of the Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle and A. Young) alliance is being severely interrupted by post-fire invasion of non-native annual grasses. To curtail this invasion, successful post-fire revegetation of perennial grasses is required. Environmental factors impacting post-fire restoration success vary across space within the Wyoming big sagebrush alliance; however, most restorative management practices are applied uniformly. Our objectives were to define probability of revegetation success over space using relevant soil-related environmental factors, use this information to model cost of successful revegetation and compare the importance of vegetation competition and soil factors to revegetation success. We studied a burned Wyoming big sagebrush landscape in southeast Oregon that was reseeded with perennial grasses. We collected soil and vegetation data at plots spaced at 30 m intervals along a 1.5 km transect in the first two years post-burn. Plots were classified as successful (>5 seedlings/m~2) or unsuccessful based on density of seeded species. Using logistic regression we found that abundance of competing vegetation correctly predicted revegetation success on 51 % of plots, and soil-related variables correctly predicted revegetation performance on 82.4 % of plots. Revegetation estimates varied from $167.06 to $43,033.94/ha across the 1.5 km transect based on probability of success, but were more homogenous at larger scales. Our experimental protocol provides managers with a technique to identify important environmental drivers of restoration success and this process will be of value for spatially allocating logistical and capital expenditures in a variable restoration environment.
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