A METHOD OF PHENOLOGICAL SURVEY FOR USE IN FOREST INSECT STUDIES

1956 ◽  
Vol 34 (6) ◽  
pp. 533-540 ◽  
Author(s):  
R. F. Morris ◽  
F. E. Webb ◽  
C. W. Bennett

To ensure correct sequence in the timing of insect sampling or control operations over a large forest area it is desirable to know what phenological differences may be expected. Measurements of shoot elongation provide a simple and objective method for comparing a large number of phenological stations in one season. By this method one or more reference stations have to be visited weekly to permit the plotting of growth curves, but the great majority of the stations have to be visited only twice a year. At any one station the major source of variance in cumulative shoot growth on a given date is between trees and the optimum allocation of sampling resources will usually be based on the selection of one shoot per tree and 10 or more trees of balsam fir per station. The variance is greater for cherry and larger samples are necessary.

1970 ◽  
Vol 48 (6) ◽  
pp. 1093-1097 ◽  
Author(s):  
D. T. Lester

Measurements of total height and frequency of frost damage on 5-year-old trees demonstrated moderate to large variation associated with seed origin. Total height was measured at three nurseries in Wisconsin and Minnesota. Frost damage was measured at one nursery in central Wisconsin. The tallest seedlings were from eastern provenances. The seedlings least damaged by spring frost were from Wisconsin and Michigan provenances. Periodic measurements of shoot elongation indicated that variation in rate of elongation was the chief determinant of variation in total shoot elongation. Variation in time of shoot growth initiation was one cause of observed variation in frequency of frost damage. Variation among maternal progenies from six populations in Wisconsin and Michigan was similar to variation among range-wide provenances.


1977 ◽  
Vol 7 (4) ◽  
pp. 584-588 ◽  
Author(s):  
D. T. Lester ◽  
S. E. Lindow ◽  
C. D. Upper

Three-year-old seedlings of balsam fir (Abiesbalsamea (L.) Mill.) representing provenances with different rates of shoot growth initiation were exposed to four temperatures between −3.3 and −8.5 °C at two different times during shoot elongation. Exposure at −3.3 °C resulted in no bud, shoot, or leaf injury. Exposure at −8.5 °C resulted in injury to 53% of 2000 buds and shoots tested. Differences in provenance and in timing of exposure were significant at lower temperatures. Freezing injury was largely a function of the developmental stage of buds and shoots at each temperature of −4.5 °C or lower. One-year-old leaves were severely damaged at lower temperatures and effects of provenance and timing of exposure were present.


2008 ◽  
Vol 12 (3) ◽  
pp. 825-839 ◽  
Author(s):  
L. Gaál ◽  
J. Kyselý ◽  
J. Szolgay

Abstract. The paper compares different approaches to regional frequency analysis with the main focus on the implementation of the region-of-influence (ROI) technique for the modelling of probabilities of heavy precipitation amounts in the area of the Western Carpathians. Unlike the conventional regional frequency analysis where the at-site design values are estimated within a fixed pooling group (region), the ROI approach as a specific alternative to focused pooling techniques makes use of flexible pooling groups, i.e. each target site has its own group of sufficiently similar sites. In this paper, various ROI pooling schemes are constructed as combinations of different alternatives of sites' similarity (pooling groups defined according to climatological characteristics and geographical proximity of sites, respectively) and pooled weighting factors. The performance of the ROI pooling schemes and statistical models of conventional (regional and at-site) frequency analysis is assessed by means of Monte Carlo simulation studies for precipitation annual maxima for the 1-day and 5-day durations in Slovakia. It is demonstrated that a) all the frequency models based on the ROI method yield estimates of growth curves that are superior to the standard regional and at-site estimates at most individual sites, and b) the selection of a suitable ROI pooling scheme should be adjusted to the dominant character of the formation of heavy precipitation.


2005 ◽  
Vol 25 (2) ◽  
pp. 247-265 ◽  
Author(s):  
E. Borghi ◽  
M. de Onis ◽  
C. Garza ◽  
J. Van den Broeck ◽  
E. A. Frongillo ◽  
...  

2021 ◽  
Vol 42 (6supl2) ◽  
pp. 4059-4072
Author(s):  
Marcos Paulo Gonçalves de Rezende ◽  
◽  
Paulo Luiz Souza Carneiro ◽  
Riccardo Moretti ◽  
Johnny Iglesias Mendes Araujo ◽  
...  

The selection of animals with lower production costs can be achieved by using feed efficiency and growth curve information. Kleiber ratio (KR) is an alternative option for discriminating against the animals that have the greatest weight gain about their final weight. Alternative feed efficiency and growth curves for ostriches of the African Black (AB) and Red Neck (RN) breeds and their crossbreeds (CB) were investigated using KR and Gompertz equation. Univariate and multivariate analyses were used. The highest adult weight was identified in the RN and CB. AB was more precocious than the RN and CB individuals. Only AB animals reached 75% of their mature weight at one year of age. At 180 days, AB showed better KR. AB was different from the others, mainly for KR at 90 days and 180 days. Considering multivariate analysis, AB animals were different from the others, regardless of sex, mainly for KR at 90 days and KR at 180 days. Other subgroups separated the animals by sex. In a market preferring animals of minor structure (smaller cuts) and greater precocity, it would be suitable to opt for AB. When animals with greater body structure (larger cuts) are desired, males RN and CR is the best option, however, it will be slaughtered with greater age and lower value for KR (may generate a bigger production cost ). It is possible to obtain animals with precocity and high KR, being well represented by the AB breed.


1984 ◽  
Vol 14 (3) ◽  
pp. 447-451 ◽  
Author(s):  
C. H. A. Little

The entire crown of variously fertilized, unsheared Abiesbalsamea (L.) Mill. trees was sprayed once or twice weekly for 2, 4, or 8 weeks with an aqueous solution of 0 or 600 mg 6-benzylaminopurine (BAP) L−1 containing 1.5% dimethyl sulfoxide, 13.5% methanol, and 0.1% Tween 20, starting at different times during the period of shoot elongation. In the year of application, BAP inhibited the elongation of the current-year shoot, increased the number of lateral buds formed on this shoot, and induced lammas growth. Both BAP and the carrier solution caused some phytotoxicity in current-year needles. Responses to BAP treatment varied markedly with genotype, whorl position, and time of application, and decreased with mineral deficiency, and decreasing BAP dosage. After overwintering, many of the BAP-induced lateral buds elongated, resulting in an increased number of shoots, hence in a denser crown.


1981 ◽  
Vol 11 (4) ◽  
pp. 789-795 ◽  
Author(s):  
S. Thompson

When seedlings of a single seed source of Scots pine (Pinussylvestris L.) were raised for 26 weeks in a naturally lit, heated greenhouse, two types of shoot morphology were observed. Type 1 was that normally found in 1-year-old seedlings. Type 2 had a shoot morphology similar to that of seedlings raised outdoors for two growing seasons. When compared with type 1 plants, type 2 plants had an earlier start to shoot elongation, set their buds earlier, and stopped shoot elongation sooner. After one growing season, type 2 plants were shorter, had fewer stem units for shoot elongation in the second season, but carried a greater foliage biomass than 1-year-old type plants. After two seasons they remained shorter. Thus, plant rearing practices which result in the production of seedlings with this type of shoot morphology arc undesirable.The relationship between early "budsct," shoot morphology, and plant height suggests that the proportion of seedlings with a 2-year-old shoot morphology after one growing season in a heated greenhouse may be used as an early test for height growth potential in seed origins and possibly in progenies of north temperate pine species.


2015 ◽  
Vol 40 (3) ◽  
Author(s):  
Gülhan Orekici Temel ◽  
E. Arzu Kanık ◽  
Didem Derici Yildirim ◽  
H. Didem Ovla ◽  
Hakan Kalafat

AbstractObjective: The main objective of this study is to determine the methods used for dividing reference data into sub-groups and propose a new solution. Therefore, the newly proposed method is used to determine age sub-groups while calculating the reference interval of AST variable.Methods: The data of this study are composed of the registered patients who applied only once to the polyclinics at the Health Research and Application Hospital, Clinical Bio-Chemistry Laboratory of Mersin University. The main variables selected for the study are sex, age and aspartate transaminase (AST). MARS 2.0 package software was used for the statistical analysis. Harris&Boyd method was used for sex and age while the MARS method was used for the determination of age sub-groups.Results: According to the Harris&Boyd method, it was concluded that it is not necessary to create sub-groups for sex and age variables. Age sub-groups are determined with the MARS method by taking into account the correlations between AST variables and age. Age sub-groups are calculated as 5-9, 10-18 and 19+. Correlation between the age and AST variable is investigated for these sub-groups. It is obtained that the correlation is statistically not significant for the 5-9 age group (p=0.3189), significant for the 10-18 age group (p<0.001) and significant for 19 and above (p<0.001).Conclusion: The selection of transformation and outlier value elimination method and especially determination criteria for separation of sub-groups are made according to researcher’s subjective desicions in the application of many studies. Because of this reason, MARS can be used as an alternative and objective method for determining subgroups. In addition, results of MARS method being parallel with the findings of the producing company supported the usage of this method for determination of sub-groups.


2004 ◽  
Vol 44 (3) ◽  
pp. 353 ◽  
Author(s):  
R. S. Tegg ◽  
P. A. Lane

The increased use of semi and fully enclosed sports stadiums necessitates the ongoing selection, development and assessment of shade-tolerance in turfgrass species. Vertical shoot growth rate is a simple biological measure that may supplement visual turfgrass assessment and provide a useful measure of shade adaptation. Cool-season temperate turfgrasses; Kentucky bluegrass–perennial ryegrass (Poa pratensis L.–Lolium perenne L.), creeping bentgrass (Agrostis palustris Huds.), supina bluegrass (Poa supina Schrad.) and tall fescue (Festuca arundinacea Schreb.), and a warm season species, Bermudagrass (Cynodon dactylon L.), were established in pot and field experiments and subjected to 4 shade treatments (0, 26, 56 or 65% shade) under ambient conditions. Average light readings taken near the winter and summer solstice in full sunlight at midday, were 790 and 1980�μmol/m2.s, respectively. Field and pot trials confirmed supina bluegrass and tall fescue to have the greatest shade tolerance, producing high turf quality under 56 and 65% shade. However, all turfgrass species declined in quality under high shade levels as indicated by an increase in thin, succulent vertical growth, and a less-dense turf sward. Vertical shoot growth rates of all species increased linearly with increasing shade levels. Kentucky bluegrass–perennial ryegrass had the highest rate of increase in vertical shoot elongation under shade, approximately 3.5 times greater than supina bluegrass, which had the lowest. Low rates of increase in vertical shoot elongation under shade indicated shade tolerance whereas high rates inferred shade intolerance.


1985 ◽  
Vol 15 (4) ◽  
pp. 618-624 ◽  
Author(s):  
Stephen D. Ross

Young, potted grafts ofPiceaengelmannii were moved into a 30:20 °C (day:night) heated polyethylene house at different stages of lateral shoot elongation; and there they were subjected to low, moderate, or severe drought stress with and without branch applications of gibberellin A4/7 (GA4/7). The critical time for promoting flowering by high temperature was the late stage of slow shoot elongation, whereas for drought it was during early and rapid shoot growth. Each treatment inhibited flowering at the time the other was maximally effective and the effective treatment period for GA4/7 appeared to include that both for high temperature and drought. In contrast to drought, optimally timed heat treatment did not retard shoot elongation, nor did it result in a decreased needle water potential relative to well-watered grafts outdoors. It appears that heat and drought promote flowering through different mechanisms, albeit mechanisms which may be mediated, at least in part, through their influence on gibberellin metabolism. Advantages of indoor-potted orchards over conventional soil-based orchards for accelerating the breeding and production of genetically improved P. engelmannii seeds are discussed.


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