Annual Cycle Of Development Research Articles

Multivorious Sucking Insects and Mites Pests of Vegetables and Melons in Open and Covered Ground in Uzbekistan

To obtain a high yield of these crops, it is necessary to conduct skillful science-based pest control. For the effective implementation of protective measures, it is necessary to know the species composition, the annual cycle of development, the conditions that promote and suppress the development of pests and pathogens, their harmfulness, methods and means of combating them. Melon and pumpkin vegetable crops are damaged by polyphagous sucking pests that also parasitize other crops. The most common of them are melon aphid, whitefly, spider mite, tobacco thrips, bedbugs.

Biocollection of species of the genus barrenwort (Epimedium L.) in the botanical garden VILAR

Representatives of the genus Epimedium L. (family Berberidaceae) are herbaceous spring-flowering perennials with medicinal and decorative significance. The collection of the VILAR Botanical Garden contains three species of the genus of the Russian Federation flora - E. colchicum (Boiss.) Trautv., E. koreanum Nakai, E. macrosepalum Stearn and three hybrid taxa widely used as ornamental plants - E. х rubrum E. Morren, E. х versicolor E. Morren, E. х warleyense Stearn. The article presents the results of studying the phenological features of the seasonal development of four species of the genus Epimedium in the conditions of the VILAR Botanical Garden. It is shown that, in the conditions of the Botanical Garden, they go through the phases of the annual cycle of development, with the exception of fruiting; winter-hardy and drought-resistant, not affected by diseases; reproduce vegetatively; retain decorative foliage until late autumn; E. col-chicum (Boiss.) Trautv. keeps winter green leaves during wintering. The species E. colchicum, E. х rubrum, E. Morren, E. х versicolor are distinguished by long flowering. The introduction of rare and endangered representatives of this genus (E. colchicum, E. koreanum, E. macrosepalum) into the culture will contribute to the conservation of their diversity ex situ.

Autumn dynamics of phytoplankton, zooplankton and nutrients contents in the Novorossiysk harbour, the northeastern Black Sea

Nutrients contents, dissolved oxygen, numerical density, abundance of phytoplankton, holoplankton and meroplankton were obtained in the harbour of Novorossiysk Bay in the autumn season. At the beginning of the autumn 2015, the optimal water temperature in the upper layer of water and the absence of zooplanktonophagous (ctenophore predators) led to the intensive development of plankton communities. The phytoplankton was represented mainly by diatoms algae and zooplankton – by cladoceran, copepods and larvae invertebrates. However, at the beginning of autumn no meaningful relationship between plant and animal components, contents of nutrients and phytoplankton can be found. The zooplankton contained metazoan organisms with a wide range of nutrition including detritophagous. During the autumn season, the phytoplankton community began to transit at the mixotrophic-heterotrophic phase of the annual cycle of development. Probably in the Novorossiysk harbor, the detritus is the most important component in the biotic cycle of matter and energy.

Ріст і розвиток рослин Аsphodeline lutea Rchb. в культурі

The purpose of this work was to investigate ontomorphogenesis of Asphodeline lutea (L.) Rchb. (a rare Mediterranean species of plants for Ukraine) in culture, to analyze the features and describe plants in а different age stages and the sequence of their passage by individuals outside of the natural area in M.M. Gryshko National Botanical Garden of the National Academy of Sciences of Ukraine (Kyiv). In the article detailed morphological descriptions of plants in different age stages are given. The plants were studied in culture. Observations were conducted during 5 year period (2014-2019). The growth and development of individuals in this article are considered as components of ontogenetic changes in plants within a large life cycle. Ontomorphogenesis was studied by conventional methods. For the description of the ontogenetic development degree of individuals, the terms "age-stage" and "age-period" are used. To describe the variation of the passage by individuals of ontogeny stages we divided stages into ontomorphs, which determined the degree of development-degradation of plants. Due to the fact that A. lutea is included in the Red Book of Ukraine (2009), after research of the the specimens they were planted in the soil for further growth. It has been established that A. lutea plants go through four periods of ontomorphogenesis and eight age stages in culture. Plants annually bloom, form seeds and seedlings. As a result of observations of individuals, it has been established that A. lutea plants are drought-resistant and winter-stable in Kyiv, and their annual cycle of development depends on seasonal climatic variations. Asphodeline lutea is a perennial herb with a short rhizome and monocarpic generative shoots, vegetatively mobile. The underground part is a rhizome with renewal buds and stocking roots. Vegetative recovery occurs from underground buds. Pregenerative period lasts 5 years or more. Seedlings and juvenile plаnts are formed during one period of vegetation. Due to the degree of development of juvenile and immature plants they are divided into ontomorphotypes. Such differentiation determines the possibility of multivariate development in individuals. We noted that the virginіle plants can be represented as a separate shoots or а clone, that is formed as a result of "tillering". In the generative period a further vegetative growth is characteristic for A. lutea, which is successfully used for artificial vegetative reproduction of these plants in culture. Formation of subsenile and senile plants is a result of prolonged cultivation in one place or in stressful conditions. In the postgenerative period of ontogenesis for the preservation of plants in a culture, it is necessary to "rejuvenate" them by separating and planting members of clonе to a new place. Due to the biological characteristics of the species, the examination of plants for the study of the ontogenetic structure of cenopopulations is best carried out during flowering, as later on, an overland part of the juvenile species may already be absent, which will affect the assessment of the age range of the population.

Temporal and Spatial Variation of Terpenoids in Eastern Hemlock (Tsuga canadensis) in Relation to Feeding by Adelges tsugae

The terpenoid content of eastern hemlock (Tsuga canadensis) foliage was measured over an annual cycle of development from bud opening, shoot elongation, shoot maturation, to bud-break at the start of the next growing season. The objective was to determine if variation in terpenoid composition is linked with spatial and temporal feeding preferences of the hemlock woolly adelgid (HWA; Adelges tsugae). The HWA has two periods of feeding over the course of 1 yr spanning two complete generations. There are two periods of feeding separated by a nonfeeding period where the adelgid estivates. HWA prefers to feed on mature, rather than young, expanding tissue. Feeding occurs in the leaf cushion at the base of the needle. The needle is the only tissue in hemlock with resin canals that store terpenoids. The needle and leaf cushion of both the current and previous years' growth were analyzed separately over a 1-yr period to examine the variation of terpenoid composition in space and time. Terpenoids were quantified by using headspace solid-phase microextraction/gas chromatography/mass spectrometry (SPME/GC/MS). New growth needles and leaf cushions do not resemble the previous year's growth either visually or in chemical composition until October/November, when the adelgid breaks estivation and begins feeding. Nearly all of the 23 terpenoids present exceeding 0.1% varied significantly either temporally or spatially, usually with complex interactions. Ordination and factor analysis revealed that terpenoids are less variable in mature leaf cushions than in young tissue. By entering a nonfeeding diapause during the late spring and summer, HWA avoids the unstable, variable levels of terpenoids in the immature leaf cushion and needles.

Adaptation of the timing of bud burst of Norway spruce to temperate and boreal climates

The adaptation of the annual cycle of development of boreal and temperate trees to climatic conditions has been seen as a result of stabilizing selection caused by two opposite driving forces of natural selection, i.e. the tolerance of unfavorable conditions during the frost exposed season (survival adaptation) and the effective use of growth resources during the growing season (capacity adaptation). In this study, two theories of the effects of climate on the adaptation of the timing of bud burst of trees were evaluated. This was done with computer simulations by applying a temperature sum model for predicting the timing of bud burst of different Norway spruce genotypes on the basis of air temperature data from various climatic conditions. High geographical variation in the temperature response of bud burst, typical for Norway spruce, was included in the theoretical analyses. The average timing of bud burst and the corresponding risk of occurrence of damaging frost during the susceptible period after bud burst were calculated for each genotype in each climate. Two contrasting theories of the stabilizing selection were evaluated, i.e. the overall adaptedness of each genotype was evaluated either 1) by assuming a fixed threshold for the risk of frost damage, or 2) by assuming a tradeoff between the risk of frost damage and the length of the growing season. The tradeoff assumption produced predictions of between provenance variation in bud burst which correspond more closely with empirical observations available in literature, compared to the fixed threshold assumption.

Effects of climatic change on trees from cool and temperate regions: an ecophysiological approach to modelling of bud burst phenology

A framework is presented for modelling bud burst phenology of trees from the cool and temperate regions. Three ecophysiological aspects affecting the timing of bud burst are considered: (i) effects of environmental factors on the rest status of the bud, (ii) effect of rest status on the ability for bud burst, and (iii) direct effect of air temperature on the rate of development towards bud burst. Any model for bud burst phenology can be presented within the framework with three submodels, each of them addressing one of the corresponding three ecophysiological aspects. A total of 96 hypothetical models were synthesized by combining submodels presented in the literature. The models were tested in two experiments with saplings of Pinus sylvestris L. growing in experimental chambers at their natural site in eastern Finland. In the first experiment, air temperature and (or) concentration of atmospheric CO2was elevated. Elevation of the air temperature hastened bud burst, whereas elevation of the concentration of CO2did not affect it. Several models accurately predicted the timing of bud burst for natural conditions but too early for bud burst at the elevated temperatures. This finding suggests that (i) the risk of a premature bud burst with subsequent frost damage, as a result of climatic warming, was overestimated in a recent simulation study, and (ii) bud burst observations in natural conditions alone are not sufficient for the testing of these mechanistic models. Several models did predict the timing of bud burst accurately for all treatments, but none of them obtained sufficiently strong support from the findings to stand out as superior or uniquely correct. In the second experiment a photoperiod submodel for rest break was tested by exposing the saplings to short-day conditions. The short-day treatment had only a minor effect on the timing of bud burst. These results demonstrated the importance of the concept of model realism: the accuracy of a model can be lost in new conditions (e.g., global warming), unless the model correctly addresses the essential ecophysiological aspects of the regulation of timing of bud burst. Key words: annual cycle of development, chilling, dormancy, field test, photoperiod, rest break.

Thyroid-gonad and thyroid-body weight relationship in the red-vented bulbul, Molpastes cafer

Male and female gonads, but not the body weight, of the red-vented bulbul Molpastes cafer undergo an annual cycle of development. Gonads are small and inactive during winter and large and active during spring and early summer months. When during December (day length, 10.26L:13.34D) male birds were transferred to 9L:15D photoperiod, the gonads remained small and inactive, and when exposed to 15L:9D, the testes developed rapidly, reached a maximum, and then regressed. Exposure to 15L:9D during April (day length, 12.45:11.15D), however, produced no significant effect either on the size or on the rate of growth of the gonads. Thyroidectomy led to rapid collapse of the partially or fully developed testes irrespective of whether the birds were exposed to natural or long photoperiod. The body weight of the birds was not affected significantly either by day length or by thyroidectomy. It is suggested that while the thyroid is essential for sustaining the growth of the gonads and reproduction it has no significant influence on the body weight of the bird.

Studies on the Dormancy of Calluna vulgaris (L.) Hull, during Winter: The Effect of Photoperiod and Temperature on the Induction of Dormancy and the Annual Cycle of Development

The effects of daylength and temperature on the induction of dormancy in shoots of Calluna vulgaris were investigated using controlled environment growth rooms. Short days did not induce dormancy in Calluna but flowering was inhibited and shoots having a characteristic end-of-season morphology were formed. Short days combined with low temperatures arrested growth but the depth of dormancy was not as great as that of plants in the field in late autumn. Long days combined with low temperature did not induce dormancy or the end-of-season morphology. Results from the growth room experiments may be interpreted in relation to the annual cycle of development of Calluna under field conditions.

Structure and Seasonal Activity of the Vegetative Shoot Apex of Daphne pseudo-mezereum

1. The structure and seasonal activity of the vegetative shoot apex of Daphne pseudo-mezereum A. Gray were analyzed using longisections and transections. 2. There are four phases in the shoot development: the autumn-active, winter-inactive, springactive, and summer-inactive phases. 3. The apex is flat or slightly convex in longisectional view and has a somewhat complicated angular form in superficial or transectional view. 4. Both a tunica-corpus organization and a cytohistologic zonation with a central zone, peripheral meristem, and rib meristem are recognized. The number of tunica layers varies from three to seven, the mean in an annual cycle of development being above four. 5. The procambium of the stem differentiates from the third to fifth layers of the tunica. The direction of procambial differentiation is always acropetal. 6. In superficial or transectional view cells of the central zone and their derivatives are recognizable. The latter, part of the peripheral meristem, are arranged in radial files originating from the central zone. 7. The central zone, which in any one layer contains ten to twelve centrally located cells, is recognized not only by appearance but by arrangement of cells in superficial or transectional view. Cell divisions occur in the central zone. 8. Four or five "apical sectors," each of which consists of a few radial files of cells in the first, second, third, and even fourth layers of the tunica, occur on a shoot apex in connection with leaf formation. 9. An apical sector differentiates into a leaf primordium and an "evanescent apical cell connection" (or cell connection). The fully developed cell connection gives rise to a newly initiating sector and part of the stem. 10. Sectoral changes within and between apical sectors are recognizable and four growth stages are distinguished for convenience: (a) sector initiation, (b) sector development, (c) sector declination, and (d) sector destruction. Stage b may be subdivided into the stages of leaf initiation and leaf elevation. 11. The area required for an apical sector is relatively constant during the annual cycle of shoot development irrespective of fluctuation in size of the shoot apex. The number of sectors in an apex is positively correlated with the size of the shoot apex. 12. Obvious seasonal variations in the annual cycle of development of the shoot apex occur in the form and size of the apex, in the number of tunica layers, in the appearance of the central zone, peripheral meristem, and rib meristem, in development of the pith and procambium, and in correlations between sectors.