Repeseed adaptation in Northern New South Wales. II.* Predicting plant development of Brassica campestris L. and Brassica napus L. and its implications for planting time, designed to avoid water deficit and frost

1978 ◽  
Vol 29 (4) ◽  
pp. 711 ◽  
Author(s):  
AS Hodgson

Two experiments were conducted to determine the growing degree-day (D°) requirements of annual B. campestris and B. napus cultivars, and to evaluate their use in planning crop development strategies to avoid frost and moisture deficit at three locations. In the first experiment, base temperatures and D° requirements were calculated for four phases from planting to grain-filling, on the basis of linear temperature-development rate responses measured in the field at Tamworth, N.S.W. The phenological pattern of each species was predicted for several planting dates at locations representing the north-west slopes, northern tablelands and an intermediate region, by using long-term mean daily temperatures and calculated Do requirements. From these predictions and long-term mean daily rainfall and pan evaporation rates, the available soil moisture depletion was estimated for each planting date. For each location, planting date strategies for both species were evaluated for avoidance of frost and moisture deficit. The predicted optimum planting dates for B. napus and B. campestris were, respectively, 20 June and 5 August for the north-west slopes, 20 August and 1 October for the northern tablelands, and 30 June and 18 August for the intermediate region. In the second experiment, the influence of planting date on the grain yield of B. campestris and B. napus was studied in several seasons at each of the locations studied in the first experiment. The planting date that gave the highest yield varied between species and locations. B. campestris was favoured by later dates than B. napus. For both species these dates were earliest on the north-west slopes and latest on the northern tablelands. Yields of B. napus were higher than those of B. campestris at all locations when each species was planted at a favourable time. Predicted optimum planting dates from experiment 1 are discussed in relation to the field results from experiment 2. _____________________ *Part I, Aust. J. Agric. Res., 29: 693 (1978).

Author(s):  
Tatiana Vasilievna Pomogaeva ◽  
Aliya Ahmetovna Aseinova ◽  
Yuriy Aleksandrovich Paritskiy ◽  
Vjacheslav Petrovich Razinkov

The article presents annual statistical data of the Caspian Research Institute of Fishery. There has been kept track of the long term dynamics of the stocks of three species of Caspian sprat (anchovy, big-eyed kilka, sprat) and investigated a process of substituting a food item of sprats Eurytemora grimmi to a small-celled copepod species Acartia tonsa Dana. According to the research results, there has been determined growth potential of stocks of each species. Ctenophoran-Mnemiopsis has an adverse effect on sprat population by eating fish eggs and larvae. Ctenophoram - Mnemiopsis is a nutritional competitor to the full-grown fishes. The article gives recommendations on reclamation of stocks of the most perspective species - common sprat, whose biological characteristics helped not to suffer during Ctenophoram outburst and to increase its population during change of the main food item. Hydroacoustic survey data prove the intensive growth of common sprat biomass in the north-west part of the Middle Caspian. According to the results of the research it may be concluded that to realize the volumes of recommended sprat catch it is necessary to organize the marine fishery of common sprat at the Russian Middle Caspian shelf.


2008 ◽  
Vol 59 (3) ◽  
pp. 247 ◽  
Author(s):  
David W. Lester ◽  
Colin J. Birch ◽  
Chris W. Dowling

Nitrogen (N) and phosphorus (P) are the 2 most limiting nutrients for grain production within the northern grains region of Australia. The response to fertiliser N and P inputs is influenced partly by the age of cultivation for cropping, following a land use change from native pasture. There are few studies that have assessed the effects of both N and P fertiliser inputs on grain yield and soil fertility in the long term on soils with contrasting ages of cultivation with fertility levels that are running down v. those already at the new equilibrium. Two long-term N × P experiments were established in the northern grains region: one in 1985 on an old (>40 years) cultivation soil on the Darling Downs, Qld; the second in 1996 on relatively new (10 years) cultivation on the north-west plains of NSW. Both experiments consisted of fertiliser N rates from nil to 120 kg N/ha.crop in factorial combination with fertiliser P from nil to 20 kg P/ha.crop. Opportunity cropping is practiced at both sites, with winter and summer cereals and legumes sown. On the old cultivation soil, fertiliser N responses were large and consistent for short-fallow crops, while long fallowing reduced the size and frequency of N response. Short-fallow sorghum in particular has responded up to the highest rate of fertiliser N (120 kg N/ha.crop). Average yield increase with fertiliser N compared with nil for 5 short-fallow sorghum crops was 1440, 2650, and 3010 kg/ha for the 40, 80, and 120 kg N/ha, respectively. Average agronomic efficiency of N for these crops was 36, 33, and 25 kg grain/kg fertiliser N applied. This contrasts with relatively new cultivation soil, where fertiliser N response was generally limited to the first 30 kg N/ha applied during periods of high cropping intensity. Response to P input was consistent for crop species, VAM sensitivity, and starting soil test P level. At both the old and new cultivation sites, generally all winter cereals responded to a 10 kg P/ha application, and more than half of long-fallow sorghum crops from both sites had increased grain yield with P application. At the old cultivation site, average yield gain for 10 kg P/ha.crop treatment was 480 kg/ha for all winter cereal sowings, and 180 kg/ha for long-fallow sorghum. Short-fallow sorghum did not show yield response to P treatment.


Weed Science ◽  
1997 ◽  
Vol 45 (2) ◽  
pp. 261-268 ◽  
Author(s):  
Francisca López-Granados ◽  
Luis García-Torres

A mathematical model of crenate broomrape populations in broad bean as affected by cropping frequency and planting dates in the absence of crenate broomrape control practices was constructed using previously reported data. In consecutive broad bean cropping, broomrape populations reached a maximum infection severity (D) of 62, 47, and 30 emerged broomrape m−2for early (mid-October), intermediate (mid-November), and late (mid-December) planting dates, respectively. The maximumDvalues were reached earlier as planting dates were brought forward, taking from 4 to 6 yr, starting from very low initial infections (D ≤0.2 emerged broomrape m−2). If broad bean was cropped every 3 yr, 15, 21, and 27 yr were needed, respectively, according to the model, to reach the maximumDfor the three planting dates considered. A sensitivity analysis was conducted to determine the effect of changing the values of the main demographic parameters in broomrape life cycle (germination, attachment, and seed loss) on the output of the model under different management strategies (planting dates and cropping frequency). Generally, an increase in seed attachment and a decrease in seed loss affected broomrape population dynamics. Between the two processes evaluated, the time taken to reach the maximum infection severity (D) was less sensitive than the maximum broomrape population values. Model predictions were validated using results from long-term field studies at the late planting date sown every year. Simulated values generated good predictions (R2= 0.82).


Author(s):  
A. J. Southward

The inshore fishery for the pilchard in Cornish waters has existed for several hundred years, and such records as are available concerning fluctuation in catches and market conditions have been reviewed by Couch (1865), Cushing (1957) and Culley (1971). Although pilchard have been landed from Lyme Bay, from the eastern half of the Channel, and from the southern North Sea (Couch, 1865; Furnestin, 1945; Cushing, 1957; personal communications G. T. Boalch) the catches have usually been incidental to other fisheries and more sporadic than in Cornish waters. Traditionally there are three areas fished for the Cornish pilchard: on the north-west coast around St Ives; in Mounts Bay and towards the Scillies; and between the Lizard Pt and Bolt Tail in Devon (Couch, 1865; Culley, 1971). The latter region, constituting the inshore waters of south-east Cornwall and south Devon, effectively forms the eastern limits of the regular occurrence of commercial shoals. Knowledge of the breeding and life-history of the fish in this region has always been scarce and subject to much hearsay evidence (reviewed in Southward, 1963). Up to quite recently it was thought that the main spawning area lay well to the west of the entrance to the Channel, and it was not until the investigations reported by Corbin (1947,195°) a nd Cushing (1957)tnat it was conclusively shown that extensive spawning can occur within the English Channel from May to October. The relationship of the spawning in the western Channel to the other areas of spawning off the entrance to the Channel and in the northern Bay of Biscay is illustrated in a recent series of reports (Arbault & Boutin, 1968; Arbault & Lacroix-Boutin, 1969; Arbault & Lacroix, 1971; Wallace, P. D. & Pleasants, C. A., duplicated ICES meeting paper CM 1972/J: 8), and is further demonstrated by Demir & Southward (1974) in discussing the results of a study of small scale seasonal changes in spawning intensity in inshore waters.


Author(s):  
A. T. Grevtsova ◽  
T. B. Vakulenko ◽  
N. S Nоnischenko

The main task of the expeditions was the search for the following species of natural Siberian flora and theintroduction of live plants and seeds to the Botanical Garden named after acad. A. V. Fomin: Cotoneaster mongolicus.C. neo-popvii, C. tjulinae, which are currently presented in our collection. In addition, long-term phenological observations in the conditions of the north-west of Ukraine allowed to isolate new species from the imported material: C. kyachticus.C. logginovii. They are described in the materials of the XIV and XVII conferences “Problems of botany of Southern Siberiaand Mongolia”. A trip to the lake Zun-Torei was dedicated to the search for C. mongolicus. As it turned out later, under theC. mongolicus mother’s plant, we dug up a plant different from the mother’s plant, to which we gave the name C. logginovii.This article provides materials to identify the parents pair in the formation of this hybrid pitchfork. For this purpose,materials of herbarium collections from the vicinity of the lake were used Zun-Torei experienced local botanists, as wellas personal fees. Comparison of the samples allowed to establish their identity with C. mongolicus, as well as to certify it asone of the parents of C. logginovii. Morphological descriptions of annual shoots leaves, flowers, fruits, seeds of three typesof Cotoneasters: C. megalocarpus, C. mongolicus, C. yakuticus; micrographs of endocarp of bones of the previous speciesand C. logginovii, C. melanocarpus, C. uniflorus are given. The herbarium samples of C. mongolicus collected in the areaof the lake Zun-Torey were analyzed. The material is illustrated with photographs of plants introduced in the north-westof Ukraine (Kiev). The introduction of plants by the method of genus complexes by F. N. Rusanov allowed to create theCotoneaster collection, which includes 200 taxa of the genus. In the Botanical Garden named after acad. A .V. Fomin fromthe flora of Siberia preserved 11 species of Cotoneaster: C. commixtus, C. kyachticus. C laxiflorus. C. logginovii, C. lucidus,C. neo-popovii, C. megalocarpus, C. mongolicus, C. tjulinae, C. uniflorus, C. yakuticus.


Author(s):  
I. B. Uskov ◽  
◽  
K. G. Moiseyev ◽  
M. V. Nikolaev ◽  
O. V. Kononenko ◽  
...  

Purpose: to analyze the soil-climatic and anthropogenic reasons of decreasing drainage efficiency of closed pottery tubular drainage on the reclaimed lands of the North-West of Russia under the observed local weather conditions against the background of global climate changes. Materials and methods. The objects of research are seasonal precipitation regimes, reclaimed lands and drainage systems of closed tubular drainage. The methods of applied mathematical statistics, the ensemble method of processing and generalization of climate forecasts of the Intergovernmental Panel on Climate Change (IPCC), modernized by the authors were used in research. Monitoring data on changes in the physical properties of soils of reclaimed lands during their long-term operation were obtained using laboratory agrophysical methods for studying samples taken in the field. Results. It is shown that under the conditions of the observed climatic changes, the frequency, intensity and extremeness of atmospheric precipitation are increased. Long-term exploitation of lands with a leaching drainage regime is accompanied by changes in the hydrophysical properties of soils, for example, the coefficient of heterogeneity of the subsurface horizons of soils texture of automorphic genesis decreased from 26 to 6. The system “precipitation – soil – drainage” in climatically abnormal weather conditions exceeding the initial calculated precipitation level mode by 10–20 %, is unable to ensure the removal of excess moisture from the root layer. Conclusions: when creating and reconstructing such reclamation drainage systems it is recommended to take into account the tendencies of changes in the spatial-temporal statistical structure of precipitation and to design technologies for regulating the water regime with systems for intercepting and diverting surface runoff on such reclaimed lands.


Author(s):  
Xonné Haywood ◽  
Anita Elizabeth Pienaar

Poor socio-economic status contributes to undernutrition which, in turn, can increase the risk of academic underachievement. This study wants to determine if stunting, being underweight, and thinness show long term relations with academic performance in primary school girls aged 6 to 13 in the North West province of South Africa. A randomized and stratified longitudinal research design including a baseline and two time-point measurements over seven school years was used. The sample included girls aged 6 to 13 years (N = 198) in the North West province of South Africa. Academic performance in the June school assessments and national and provincial assessments in grades 1, 4, and 7 were used to determine academic performance. Independent t-testing was used to determine differences between thinness, underweight and stunted girls as opposed to a reference group with no undernutrition indices. A repeated measures ANOVA and post hoc Bonferroni adjustment analyzed relations over time. Normal weight girls significantly outperformed stunted girls academically (p < 0.05) over time. Stunting had prolonged and significant negative influences on language, mathematics, and grade point average (p < 0.05). Early identification of undernutrition, especially stunting, is important for intervention and the implementation of timely prevention strategies, especially during early childhood years.


HortScience ◽  
2006 ◽  
Vol 41 (3) ◽  
pp. 640-645 ◽  
Author(s):  
Robert J. Dufault ◽  
Brian Ward ◽  
Richard L. Hassell

The objective of this study was to determine the best combination of planting dates (PDs) and cultivars on yield and quality for long-term production of romaine lettuce. `Green Forest' (GF), `Apache' (AP), `Darkland' (DK), `Green Tower' (GT), `Ideal Cos' (IC), and `Tall Guzmaine' (TG) were successfully grown to harvest maturity on 19 PDs from September 1998 to April 2001. Lettuce planted in September and April PDs (pooled over cultivars and year), required as little as 47 and 49 days, respectively, to reach harvest (all cultivars harvested on the same day). Lettuce planted in October, November, February, and March PDs (pooled over cultivars and year), required on average 64, 66, 75, and 67 days to reach harvest, respectively, but in the coldest PDs of December and January, 90 and 98 days, respectively, were needed to reach maturity. Of the eight PDs evaluated, marketable numbers/plot (pooled over cultivars and years) were greatest in the September PD, followed by April (–8% decrease from September PD) > March (–13%) > October (–17%) > November (–21%) > December = January = February (about –30%) and heads weighed the most in September > January = February (–7% decrease from September PD) > March = April (–14%) > October (–21%) > December (–25%) > November (–31%). Cull heads/plot (pooled over cultivars and years) were greatest in April > December (–5% decrease from April PD) > January = February (–16%) > November (–27%) > October (–34%) > March (–44%) > September (–49%). Two out of three November PDs were lost to freezing damage and this PD should be avoided. Significant bolting occurred primarily in the September and October PDs (in 1 of 3 years) with negligible bolting in the November, December, and January PDs, but bolting recurred again in the February, March and April PDs. Marketable numbers/plot (pooled over all PDs and years) were greatest for GF > GT (–7% decrease from GF) > AP (–8%) > IC (–9%) > DK (–11%) > TG (–21%). The interaction effect of cultivar × PD indicated that GF yielded the most marketable heads in 6 out of 8 PDs. The best performing cultivars by PD (pooled over years) were September and February = GF and IC; October = TG; November = AP; December, January, March, and April = GF.


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