Assessment of changes in Grenache grapevine maturity in a Mediterranean context over the last half-century

This study aims to i) evaluate some descriptive variables for Grenache berry composition over the last 50 years in the southern Rhône Valley wine-growing region and ii) analyse the impacts of climate on the main annual developmental phases of the Grenache berry to understand recent changes observed in the vineyard. A large and spatialised historical, open database from the Rhône Valley grape maturity network (1969–2020) was used to explore trends in grape profile during maturity and at harvest. Then, gridded climate data was used for processing phenological stages and ecoclimatic indicators. Significant changes in grapevine phenology and maturity dynamics were found and linked with changes to ecoclimatic indicators by carrying out a correlation analysis. Depending on the phenological phases, a limited number of ecoclimatic indicators had a significant effect on the maturity profile. The results highlight direct climate impacts on different maturity and yield variables over the last 50 years. These results provide important information about future issues in grape production and the implications for managing viticulture adaptation strategies and thus serve as a basis for assessing, prioritising and optimising technical means of maintaining current grape quality and yield.This study uses an ecoclimatic approach for examining in detail the effects of climate change on the Grenache grape variety in a Mediterranean context. The open database provides the latest information from a large network of plots and over a long period of time, making it possible to validate many results recorded in the literature. This is the first study to use this open database and we wish this database could lead to further explorations and results in viticulture and climate change issues.

A study of agrometeorological parameters for the Kharif maize at Anand (Gujarat)

A study was conducted on the behaviour of evaporation, evapotranspiration and potential evapotranspiration in different phenological phases, during the years 1989, 1990 and 1991 for Kharif Maize crop at Anand (Gujarat). It has been noticed that evapotranspiration and potential evapotranspiration attained maximum values in grain phase. In harvesting phase relative evapotranspiration and crop coefficient had lowest values. The seasonal crop coefficient was obtained 0.84. An attempt has been made in this paper to develop the regression models to estimate potential evapotranspiration and relative evapotranspiration.

Growth and development of representatives of the genus Rosa L. in the Stavropol Botanical Garden

Relevance. To identify the features of the growth and development of species of roses of different geographical origin, to establish the biological minimum temperatures necessary for the beginning of flowering of representatives of the genus Rosa L., to study the morphological indicators of fruits.Methodology. The research material was 12 wild roses belonging to 4 sections: Canina Crep, Cinnamomeae DC, Luteae Crep, Pimpinellifoliae DC. The research was carried out using the methods of the Main Botanical Garden, floral and geographical analyses — according to Hrzhanovsky. A caliper was used to measure the length and diameter of 10 fruits. For the analysis of statistical data, the MS Excel table processor and the integrated MATLAB mathematical package were used.Results. The article presents the results of a study of species of roses in the Stavropol Botanical Garden of various geographical origin. The study involved 12 species belonging to 4 sections. The features of growth and development of plants in new soil and climatic conditions are revealed. The dates of the beginning of the main phenological phases andtheir duration have been established: spring regrowth of shoots, budding, beginning and end of flowering, fruiting. In the studied species of roses, the growing season begins in the first — second decade of March, flowering occurs in late May — early June, the fruits ripen in August — September. The dependence of the timing of the beginning of flowering in the studied roses on the dynamics of the accumulated average daily air temperatures and the sum of effective temperatures above 5 °C was revealed. Mathematically, it was proved that the lower limit of the air temperature required for the beginning of flowering of species of roses is +16 °C, when the sum of the average daily temperature air St° = 1007.75–1069.48 °С and St эф > 5 °С = 530.75–594.75 °С are accumulated. Early flowering species of roses include Rosa foetida Herrm., R. pendulina L., R. pimpinellifolia L., late flowering — R. caudata Baker and R. corymbifera Borkh. The shortest flowering period is in R. caudata Baker, R. jacutica Juz. and R. kamtschatica Vent. Representatives of those types mostly bloom once. Their flowers are formed on biennial and more mature shoots. The flowering period is 13–23 days. Rosa rugosa Thunb. blooms again, its flowering period is extended and long — from 40 to 48 days. All species of roses form fruits. The longest fruits are in R. pendulina L., R. caudata Baker, R. rugosa Thunb., R. corymbifera Borkh. and R. canina L., and large ones — in R. rugosa Thunb., R. marretii Lev. and R. roxburghi Tratt.

The need for the vernalization duration of soft winter wheat collection samples

The need for vernalization is a duration-dependent effect of low, positive temperatures in order to ensure the plants' transition to generative development. If the requirement for the duration of germination is not met, the plant will not enter the stage of forming generative organs. The vernalization requirements of winter soft wheat samples of different geographical origins are determined. An assessment of the vernalization period duration influence on the severity of the elements of the yield structure is given. The research material consisted of 15 cultivars of soft winter wheat of various geographic origin. The samples were germinated in paper rolls, then vernalized in a climatic chamber at a temperature of 3–5 ºС for 60, 50, and 40 days. At the end of vernalization, 10 plants of each sample were planted in a greenhouse. The dates of the onset of phenological phases were noted: tube emergence, earing, flowering. To determine the main elements of the yield structure, a structural analysis of plants was carried out. With an increase in the vernalization period, a decrease in the interfacial periods from tube emergence to flowering was noted. The influence of the timing of vernalization was noted on the manifestation of the spike length trait. It was found that the total number of stems and the number of productive stems in almost all varieties decreases with an increase in the period of vernalization. Significant differences between collection varieties in the need for vernalization, due to both their geographical origin and the genotype of plants are revealed. In all the studied forms, with an increase in the period of vernalization, the rate of plant development increased to varying degrees, the total number of stems, the productive stem and the length of the spike decreased.

Characterization and development perspectives of “Baby Kiwi “(Actinidia arguta Planch.) Culture in Georgia

The article presenta general description and development opportunities of “Baby Kiwi “(Actinidia arguta Planch,), one of the species of exotic fruit (Actinidia Lindl.), which is still in the experimental phase in Georgia and is an important topic in terms of the fruit assortment. The research has been carried out in collection orchard located in one of the leading regions of fruit-growing of Georgia - Shida (Inner) Kartli (vil. Jighaura, Saguramo Mtskheta municipality) and belonging to LEPL Scientific-Research Center of Agriculture (SRCA) in 2019-2020. The research aims at study of “Baby Kiwi “(Actinidia arguta Planch,) varieties ( Waik and Kens Reddy ) with the purpose of further propagation in Shida kartli itself and also in various fruit growing regions of Georgia. The following agronomic and biological characteristics were studied according to the cultivars: calendar periods of phenological phases; pomological description of fruits, their chemical analysis and productivity.

Features of the temperature regime effect on the duration of the crops vegetation period in Southern Ukraine

When modeling the prognostic changes in the temperature regime over the territory of Ukraine, the data of the research project for modeling the regional climate and assessing the consequences of its change (CORDEX) were used. The climate projection structure is based on a series of global climatic models (GCM) developed within the framework of CMIP5 project. The influence of the temperature factors on passing the phenological phases and oats yield in the South of Ukraine, implementing the RCP4.5 and RCP8.5 climate scenarios and comparing them with the long-term data is analyzed. As a result of the analysis of the changes in the temperature regime it was revealed that it will be warming the plants vegetation period. The probable change in the oats yield in the southern part of Ukraine under the conditions of climate change using the crop formation model was considered. It is assumed that by 2050 the timing of sowing and germinating the seedlings will be shifted to an earlier date, and the oats yield will increase by 1.26-1.32 times.

Description of Intra-Annual Changes in Cambial Activity and Differentiation of Secondary Conductive Tissues of Aesculus hippocastanum Trees Affected by the Leaf Miner Cameraria ohridella

Aesculus hippocastanum trees are commonly infested by the leaf miner Cameraria ohridella, whose larval activity causes the destruction of the leaf parenchyma and induces defoliation. Pest attacks result in, e.g., production of smaller fruits and tree re-flowering in autumn. Concerning pest influence on stem structure only scarce information of narrower annual growth rings of wood has been published. Therefore, we determined the effect of the presence of the leaf miner infestation on intra-annual cambial activity and on differentiation of conductive tissues. These data were compared with phenological phases and pest activity. Pest feeding resulted in changes in onset, cessation and duration of cambial divisions, and differentiation of secondary xylem. The duration of cambial activity was about a month shorter in heavily infested trees and was connected with premature tree defoliation. Affected trees were characterised by a reduction in cambial divisions and earlier cessation of wood differentiation resulting in narrower wood rings. Furthermore, the infested trees exhibited altered wood structure, with more vessels of smaller diameters, however these changes did not affect its theoretical hydraulic conductivity. Interestingly, pest attack did not influence secondary phloem differentiation. The probable influence of long-term infestation on tree growth and condition was discussed.

Raw materials of Hypericum perforatum L. of different geographical origin in the conditions of introduction

The results of studying the growth, development and formation of the raw phytomass of Hypericum perforatum plants of different geographic origin during the introduction in the middle taiga subzone of the Komi Republic are presented. Seven samples of Hypericum perforatum were examined, including two cultivars: Zolotodolinsky and Solnechny. A sample (Tallinn No. 885) was identified, which differed in earlier dates of the onset of phenological phases. Hypericum perforatum plants under culture conditions in the middle taiga subzone of the Komi Republic are characterized by a stable developmental rhythm. It has been determined that the number of generative shoots in Hypericum perforatum increases with age. So, in two-year-old plants this indicator was 3-4, in four-year-old plants - 18-26 pcs. per individual. It has been established that from the second year of life, with the seedling method of growing, Hypericum perforatum plants are able to form high yields of medicinal raw materials. As a result of an assessment of the productivity of samples of cultivar Solnechny and sample from Barnaul.