INFLUENCE OF TEMPERATURE ON GROWTH OF FROKER OATS FOR FORAGE.: 1. DRY MATTER YIELDS AND GROWTH RATES

1974 ◽  
Vol 54 (4) ◽  
pp. 725-730 ◽  
Author(s):  
DALE SMITH

Oats (Avena sativa L. cv. Froker) were grown to initial panicle emergence in three day/night temperature regimes; H (32/26 C), W (27/21 C), and C (21/15 C). At initial panicle emergence, some plants were transferred to the other regimes until complete panicle emergence. Plants grown continuously in the W regime reached initial panicle emergence in 34 days and complete panicle emergence in 42 days. These stages were reached about a week later in C regime and about 2 wk later in H regime. As compared with plants retained at one temperature to complete panicle emergence, moving plants at initial panicle emergence from H to W or C, or from C to H or W, decreased time to complete panicle emergence by 4 to 6 days. However, complete panicle emergence was delayed 4 to 5 days when plants were moved from W to C or H. Dry matter yields and growth rates (mg/pot/day) of plants grown continuously in the same regime to initial and to complete panicle emergence were highest, and similar, in the W and C regimes, but were significantly lower in the H. As compared with plants retained at one temperature to complete panicle emergence, changing at initial panicle emergence from H to W or C increased dry matter yields and growth rates at complete panicle emergence, whereas changing from W or C to H decreased these parameters. Yields and growth were changed very little by change from W to C or from C to W.

1975 ◽  
Vol 55 (4) ◽  
pp. 897-901 ◽  
Author(s):  
DALE SMITH

Froker oats (Avena sativa L.) was grown from seed to initial panicle emergence in three day/night temperature regimes: hot (H) 32/26 C, warm (W) 27/21 C, and cool (C) 21/15 C. At initial panicle emergence, some plants were transferred to the other regimes to provide nine temperature treatments until harvest at complete panicle emergence. High herbage concentrations of in vitro digestible dry matter (IVDDM) and total nonstructural carbohydrates (TNC) generally resulted when C temperatures prevailed after initial panicle emergence, whereas high crude protein (CP) and elemental concentrations generally resulted when H temperatures prevailed after initial panicle emergence. In general, yields (g/pot) of DM, IVDDM, TNC, CP, fat, and ash were influenced more by temperature before than after initial panicle emergence. However, yields of DM, IVDDM, and TNC were reduced markedly by the change from C to W and from C to H, and were increased by the change from H to C.


1986 ◽  
Vol 66 (2) ◽  
pp. 221-227 ◽  
Author(s):  
ZHEGONG FAN ◽  
B. R. STEFANSSON

The effect of temperature on two cytoplasmic male-sterility (CMS) systems in rape (Brassica napus L.) was investigated. These were the nap CMS system with cytoplasm which occurs in most Canadian cultivars and the pol CMS system with cytoplasm from the cultivar Polima. The day/night temperature regimes used were 22/16, 26/20 and 30/24 °C. Two floral characteristics, anther type and stamen length, were influenced by temperature treatments. Male sterility of both CMS systems was expressed consistently at the lowest temperature. The nap male-sterile plants became partially sterile at the second temperature and fully fertile at the highest temperature. The pol male-sterile plants were more stable and became partially sterile only at the highest temperature.Key words: Rape, Brassica napus L., CMS, temperature


1993 ◽  
Vol 41 (1) ◽  
pp. 91 ◽  
Author(s):  
TL Bell ◽  
JS Pate

Study of Lyginia barbata across its distribution range in south-western Australia identified five distinctive morphotypes, viz. a tall-culmed, densely tufted fire-sensitive obligate seeder (S morphotype), a tall densely tufted fire-resistant resprouter (R1), a short flexuose-culmed, tufted resprouter (R2), a weakly clonal, semi-tufted resprouter (R3) and a short-culmed, widely spreading clonal form (R4). There was little variation within a morphotype between habitat locations and no evidence of intergrading of cohabiting morphotypes. Morphotype-specific differences were observed in culm height, rhizome morphology, culm density and spikelet morphology. Differences in reproductive biology related to the time of first reproduction in juvenile recruits, spikelet number per male and female culm, ovule number per female culm and seed : ovule ratio. Differences of a physiological nature were observed in seedling growth rates and proportional biomass (dry matter) allocations to culms, rhizomes, spikelets and seeds. Comparative quantitative scorings of the above features according to concepts of r- and K-selection rated the S form strongly r-selected, the R4 form equally strongly K-selected and the other forms (R1, R2 and R3) intermediate and with the R1 form possibly more r-selected than the others. It is suggested that the data provide a basis on which future taxonomic decisions regarding the taxon might be made.


1982 ◽  
Vol 99 (1) ◽  
pp. 153-161 ◽  
Author(s):  
D. A. Davies ◽  
T. E. H. Morgan

SUMMARYHerbage characteristics of perennial ryegrass (Lolium perenne L.), cocksfoot (Dactylis glomerata L.), tall fescue (Festuca arundinacea Schreb.) and timothy (Phleum pratense L.) pastures were obtained whilst rotationally grazed by ewes and their single lambs at a fixed stocking rate of 25/ha on an upland site (305 m O.D.) in mid-Wales. Drymatter production of cocksfoot averaged 32·1 kg/ha/day over the 3-year duration of the trial (1975·7) and was 13·3 kg/ha/day lower than that of the other three grass species. This resulted in a 8 kg/ha/day reduction in dry-matter intake on cocksfoot; this was significantly lower (P < 0·05) than that achieved on the other grasses, which were similar to one another around 36 kg/ha/day.In vitro digestibility of the herbage ranked in the order perennial ryegrass > timothy = cocksfoot > tall fescue. Intake of digestible organic matter (DOMI) was lower on cocksfoot than on perennial ryegrass and timothy. Differences were also detected in crude protein, water-soluble carbohydrates and sodium composition between species.Dry-matter intake was positively correlated with herbage growth rates (r = 0·95, P < 0·001) but not to digestibility of herbage on offer (r = 0·18). Both ewe and lamb live-weight gains were positively related to intake of dry matter and DOMI.Reference is made to comparative yield data between the grasses obtained under cutting trials. In the 2nd and 3rd harvest years (1967–1967) growth rates in the grazing experiment were 76, 61, 81 and 80% of the 66·2, 66·7, 67·8 and 65·0 kg D.M./ha/day obtained under a cutting regime on perennial ryegrass, cocksfoot, tall fescue and timothy swards respectively. This illustrates the danger involved in assessing the potential of grasses based on such information.The results are discussed in relation to the value of the species for use under grazing in the uplands.


Weed Science ◽  
1978 ◽  
Vol 26 (6) ◽  
pp. 566-570 ◽  
Author(s):  
C. E. G. Mulder ◽  
J. D. Nalewaja

Experiments were conducted in controlled environmental chambers to determine the influence of temperature on the phytotoxicity of seven soil-applied herbicides. Diclofop {2-[4-(2,4-dichlorophenoxy)phenoxy] propanoic acid} soil incorporated or surface applied, was more toxic to wild oat(Avena fatuaL.) shoots at 10 and 17 C than at 24 C. Efficacy of diclofop was enhanced with soil incorporation. Diclofop toxicity to wild oat roots was not influenced by a change in temperature. EPTC(S-ethyl dipropylthiocarbamate) stimulated sugarbeet(Beta vulgarisL. ‘American Crystal Hybrid B’) shoot dry weight production at 10 C and caused dry weight reduction at 24 C. Atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] toxicity to barley(Hordeum vulgareL. ‘Larker’) and alachlor [2-chloro-2′,6′-diethyl-N-(methoxymethyl)acetanilide] toxicity to oats(Avena sativaL. ‘Chief’) increased with increased temperature from 10 to 17 C. Temperatures within the range of 10 to 24 C did not affect trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine) toxicity to barley or BAY-5653 [N-(2-benzothiazolyl)-N-methylurea] or chloamben (3-amino-2,5-dichlorobenzoic acid) toxicity to oats.


1979 ◽  
Vol 19 (99) ◽  
pp. 437 ◽  
Author(s):  
AC Andrews ◽  
FC Crofts

Four ecotypes of hybrid Bermudagrass (Cynodon dactylon) were compared with common couch (C. dactylon) and kikuyu (Pennisetum clandestinum) at five sites in coastal districts of New South Wales. The sites were Grafton and Coaldale (Lat. 30�S), Mitchells Island (Lat. 32�S) and Richmond and Badgerys Creek (Lat. 34�S). Hybrid Bermudagrass ecotypes 6389 and 692 were established quickly at all sites while ecotypes 71 9 and 632 were satsifactory. Kikuyu was strong at all sites except Grafton but the rate of establishment of common couch was poor. At the frost-free sandy site of Mitchells Island, Bermudagrass ecotypes 719, 692, 6389, and 632 outyielded kikuyu by 75, 65, 65 and 35%, respectively. However, at Grafton and Coaldale, the highest yielding Bermudagrass ecotype, 719, had only 35% higher production than kikuyu. At the frost prone southern sites of Richmond and Badgerys Creek, the annual production of kikuyu was equal to that of ecotypes 719, 6389, 692 and 632. Common couch yields were equal to kikuyu at all sites except at Richmond. At Mitchells Island, the hybrid Bermudagrasses outyielded kikuyu in spring, summer and early autumn but in the late autumn kikuyu had equal and sometimes higher growth rates than the best Bermudagrasses. In winter, the growth of both species was negligible, although kikuyu, unlike the Bermudagrasses, did produce some new shoots at the base of the sward. Data on persistence under grazing were collected from only three of the sites but trends were similar to establishment. Ecotype 6389 had the highest persistence rating of the Bermudagrasses. Kikuyu failed at the poorly drained sandy site of Grafton but remained strong at the other sites. It was concluded that hybrid Bermudagrasses were of potential value for pastures in New South Wales, especially for sites with sandy soils and low frost incidence.


The law of Neumann assumes that when an atom enters into chemical combination it retains the same capacity for heat as when in the uncombined or elemental state. This generalisation is, however, based on the values observed for the mean specific heats of elements and their compounds between 0° and 100° C. Attention was directed in Part II. of this investigation to the great differences found in the influence of temperature on the specific heats of various metals, such as aluminium on the one hand, and silver or platinum on the other. The experiments now about to be described were undertaken with the object of ascertaining to what extent these differences persist in the compounds of such elements.


Agromet ◽  
2018 ◽  
Vol 28 (1) ◽  
pp. 33
Author(s):  
Muhammad Syafei ◽  
Rini Hidayati

<em>This study aimed to determine the effect of altitude and rainfall on the incidence of disease ( IR ) diarrhea, and to obtain threshold values ​​of rainfall that often cause diarrhea. Determination category of normal rate of diarrhea IR is based on diarrhea IR by DINKES Bogor in the amount of 20-25/1000 population per year, while the determination of precipitation category is based on consideration of Oldeman climate classification. The results showed that there were two districts with very high levels of vulnerability i.e.  Cisarua and Cijeruk, while the other regions only at a moderate level. The negative influence of altitude (or positive influence of temperature) on the IR will be evident if the analysis is separated between in the highlands (&gt; 600 asl) and the lowlands (&lt; 600 asl). This influence is significant, especially at altitudes above 600 meters above sea level. The correlation of the precipitation is significant negative linear to the incidence of diarrhea in the district Cisarua, Cibinong, Jonggol, and Jasinga. In districts Cibinong, Jonggol, and Jasinga, precipitation should be anticipated in the range of 100-200 mm/month, where moderate IR often occurs, while in the district Cisarua, is in the range of precipitation 300-400 mm/month, where high IR often occurs.</em>


Author(s):  
B.G. Croy ◽  
W.C. Weeda

In 1971-3 and 1972-4 two successive generations of Friesian male weaners were carried to slaughter on two self-contained farmlets, one all pasture, the other with half its area in pasture and half in lucerne. The pasture farmlet produced slightly less herbage dry matter than the pasture/lucerne farmlet. Average net hot carcass production was 922 and 829 kg/ha/yr respectively. The stocking rate was 4.85 animals/ha with an overlap of two generations from November to February. Herbage yields and animal intakes were estimated by before and after grazing cuts. The lucerne was grazed at a 40-day rotation in its growing season. To obtain high cattle growth rates, much stalk was left ungrazed, being 15 to 20% of the total dry matter standing before grazing above a height of 3 to 4 cm. Overall conversion efficiency of ingested forage was lower on the lucerne/pasture farmlet than on the pasture farmlet and it was also more variable on the former. With the grazing rotation and pressure adopted in this trial, bloat was no serious problem.


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