scholarly journals Alternaria diseases of agricultural crops in Uzbekistan

2020 ◽  
Vol 13 (2) ◽  
pp. 062-067
Author(s):  
Gulchehra Kulmuminovna Khalmuminova ◽  
Shukhrat Ganievich Kamilov ◽  
Olga Antonovna Verushkina ◽  
Mutabar Kushakovna Khujanazarova
Keyword(s):  
Species Composition ◽  
Preliminary Data ◽  
Agricultural Crops ◽  
Vegetable Crops ◽  
Biochemical Traits ◽  
Accurate Identification ◽  
Crop Species ◽  
Wide Range ◽  
Pure Cultures ◽  
Identification Of Species

In the article the tasks have been set on the inventory of the species composition of fungi of the genus Alternaria Nees ex Walroth - pathogen of various Alternaria diseases of vegetable crops in Uzbekistan. More than 200 isolates were collected and about 150 monosporous pure cultures were obtained from them. According to preliminary data, they belong to 15 species of the genus Alternaria and have been isolated from the 12 most important crop species. It was found that a more accurate identification of species requires the study of a wide range of morphological and biochemical traits. The article discusses the issue of infection of vegetable seeds in Uzbekistan. The composition of micromycetes living on seeds of vegetable and green crops was revealed. In total, 21 species were recorded, of which 9 species includes to Alternaria genus.

scholarly journals DISTRIBUTION OF BRYOPHYTES OF AGALYK BASIN (KARATEPA MOUNTAINS OF ZERAVSHAN MOUNTAIN RANGE)

2015 ◽  
Vol 4 (2) ◽  
pp. 80-82
Author(s):  
Holmurod Akimovich Zhalov
Keyword(s):  
Species Composition ◽  
Point Of View ◽  
Mountain Range ◽  
Decayed Wood ◽  
Moss Species ◽  
Comparative Analyses ◽  
Wide Range ◽  
Identification Of Species ◽  
Characteristic Features ◽  
Research Period

From bryological point of view Zeravshan mountain range remains one of the least studied region. Identification of species composition of true mosses and their ecological-biological peculiarities were not earlier aimed for this region. In the territory of Agalyk basin Karatepa mountains can be divided into four types of substrates where moss species occur: soil, bark of living trees, decayed wood, stones. Characteristics of substrate groups become complicated due to wide range of ecological valency of moss species. Most species select not only one, but several substrates for their settling. During the research period in the soils of Agaliksay basin 20 species were recorded belonging to 13 genera and 10 family. On decayed wood 9 species were recorded belonging to 7 genera and 5 family. On the bark of living trees 15 moss species were recorded belonging to 8 genera and 6 family. Epilyte bryophytes occurred on rocky substrates. On rocky substrates of Agaliksay basin 34 moss species were recorded from 16 genera and 13 family. On the basis of results obtained during the study of substrate groups of mosses in Agaliksay basin, we have conducted comparative analyses of studied substrate groups with the purpose of determining their characteristic features.

THE BIOLOGY OF CANADIAN WEEDS.: 58. Galinsoga parviflora and G. quadriradiata (= G. ciliata).

1983 ◽  
Vol 63 (3) ◽  
pp. 695-709 ◽  
Author(s):  
S. I. WARWICK ◽  
R. D. SWEET
Keyword(s):  
Growing Season ◽  
Biological Information ◽  
Vegetable Crops ◽  
Crop Species ◽  
Short Period ◽  
Wide Range ◽  
Self Compatibility ◽  
Viable Seeds ◽  
Agricultural Areas ◽  
Disturbed Habitats

A summary of biological information is provided on two species of Galinsoga — G. parviflora (small-flowered galinsoga) and G. quadriradiata (hairy galinsoga). Originating in Central America, both species are weeds of disturbed habitats and agricultural areas, occurring in most of the temperate and subtropical regions of the world. In recent years the galinsogas have become troublesome weeds of low-growing vegetable crops in northeastern North America. The two species serve as alternate hosts for many insects, viruses and nematodes which affect crop species. Both species possess several features which predispose them to weediness and contribute to a rapid buildup of populations after an initial infestation. These include lack of seed dormancy, lack of special requirements for germination, rapid seedling development, the ability to flower after a short period of vegetative growth, the production of flowers and fruits throughout the growing season, the production of several generations in a single growing season, self-compatibility and the production of large numbers of viable seeds under a wide range of environmental circumstances.Key words: Galinsoga parviflora, G. quadriradiata, biology

Bemisia tabaci (MEAM1) (silverleaf whitefly).

2021 ◽  
Author(s):  
Andrew Cuthbertson
Keyword(s):  
Bemisia Tabaci ◽  
Plant Viruses ◽  
Biological Traits ◽  
Vegetable Crops ◽  
Indigenous Plants ◽  
Crop Species ◽  
Wide Range ◽  
The World ◽  
High Level ◽  
Agricultural Regions

Abstract The exact origin of the MEAM1 species of Bemisia tabaci, and the reasons why it became such an important pest are still not fully known. MEAM1 was first identified in the mid 1980s when it invaded the southern states of North America. Vast numbers of whiteflies were found to be infesting winter vegetable crops and consequently caused an estimated $500 million loss to the 1991 winter harvest in California. Investigations led to the assumption that the B biotype had spread to the USA on ornamental plants that were being transported around the world. Species such as poinsettia and gerbera were highlighted as probable hosts. During the 1990s MEAM1 was reported on every continent. Biological traits of MEAM1 implied that it had evolved within intensive agricultural regions with exposure to pesticides and modern cultural practices. These included an ability to feed and develop on a wide range of plant and crop species, a high level of fecundity and a predisposition to develop resistance to a wide range of pesticides. MEAM1 is also an effective vector of many different plant viruses which, in conjunction with its high level of polyphagy, make it extremely problematic within agricultural regions where crops may be susceptible to viruses acquired from indigenous plants. Despite B. tabaci being a tropical/sub-tropical whitefly species, MEAM1 is often transported on plant species to temperate regions of the world. Within these cooler regions, MEAM1 can survive within a protected environment and could feasibly spread virus diseases to new locations. It is for this reason that B. tabaci and members of its species complex, including MEAM1, are on EPPO A2 Alert list.

Analysis of production of main crops in Orenburg region

2021 ◽  
pp. 12-31
Author(s):  
Kh. B. Dusaev ◽  
A. H. Dusaeva
Keyword(s):  
Agricultural Sector ◽  
Climatic Conditions ◽  
Agricultural Crops ◽  
Vegetable Crops ◽  
Gradual Reduction ◽  
Orenburg Region ◽  
Regional Production ◽  
Wide Range ◽  
Leguminous Crops ◽  
Agroindustrial Complex

The article analyzes the regional production of major agricultural crops for 2000–2018, taking into account the areas of their crops and planting, gross harvest and yield in farms of all categories and agricultural organizations. During the study period, a gradual reduction in the acreage of grain and leguminous crops in the region was revealed, with stabilization at the level of 2.7 million hectares, with a wide range of variations in gross yields and yields depending on the weather and climatic conditions of cultivation. There was a reduction in the area, a decrease in gross collections and a tendency to increase the yield of potatoes and vegetable crops in farms of all categories. Measures are proposed to optimize the acreage, increase the gross yield and productivity of the main agricultural crops in the agricultural sector of the regional agroindustrial complex.

Analysis of the production of major agricultural crops in the Orenburg region

2021 ◽  
pp. 51-71
Author(s):  
Kh. B. Dusaev ◽  
A. Kh. Dusaeva
Keyword(s):  
Agricultural Sector ◽  
Climatic Conditions ◽  
Industrial Complex ◽  
Agricultural Crops ◽  
Vegetable Crops ◽  
Orenburg Region ◽  
Wide Range ◽  
The Russian Federation ◽  
Leguminous Crops

A detailed analysis of the production of the main agricultural crops in the Orenburg region for a long-term period, taking into account of their sown areas, gross yields and yields in farms of all categories has been provided in the article. The purpose of the research was to analyze the production of the main agricultural crops in the Orenburg region. Based on the conducted research, transformational changes and trends in the regional production of grain, potatoes and vegetable crops have been identified. During the study period, a gradual reduction in the acreage of grain and leguminous crops in the region was revealed with stabilization at the level of 2,7 million hectares with a wide range of variations in gross yields and productivity depending on the weather and climatic conditions of cultivation. The gross harvest of grain and leguminous crops in farms of all categories during the study period varied in a very wide range of 739,6–4207,2 thousand tons. The biggest gross harvests of grain and leguminous crops were observed in 2000, 2016 and 2017, respectively, 3141,7, 3138,6 and 4207,2 thousand tons in association with the most favorable natural and climatic conditions of their cultivation. There was the reduction in the area, the decrease in gross yields and the tendency to increase the yield of potatoes and vegetable crops in farms of all categories. Based on the analysis, measures are proposed to optimize the acreage, increase the gross yield and productivity of the main agricultural crops in the agricultural sector of the regional agro-industrial complex, as well as a set of measures for sustainable development and effective functioning of regional agricultural production with the possibility of applied use in other regions of the Russian Federation.

An Improved Membrane Filtration Method for Enumeration of Faecal Coliforms and E. Coli by a Fluorogenic β-Glucuronidase Assay

1993 ◽  
Vol 27 (3-4) ◽  
pp. 267-270 ◽  
Author(s):  
M. T. Augoustinos ◽  
N. A. Grabow ◽  
B. Genthe ◽  
R. Kfir
Keyword(s):  
Escherichia Coli ◽  
Water Samples ◽  
Membrane Filtration ◽  
Faecal Coliforms ◽  
Environmental Waters ◽  
Filtration Method ◽  
E Coli ◽  
Wide Range ◽  
Pure Cultures ◽  
Glucuronidase Assay

A fluorogenic β-glucuronidase assay comprising membrane filtration followed by selective enumeration on m-FC agar at 44.5°C and further confirmation using tlie 4-metliylumbelliferyl-β-D-glucuronide (MUG) containing medium was evaluated for the detection of Escherichia coli in water. A total of 200 typical blue and non-typical blue colonies were isolated from sea and fresh water samples using initial selective enumeration on m-FC agar. Pure cultures of the selected colonies were further tested using the MUG assay and identified using the API 20E method. Of the colonies tested which were shown to be positive using the MUG assay 99.4% were Escherichia coli. The results of this study indicate the combination of the m-FC method followed by the MUG assay to be highly efficient for the selection and confirmation of E. coli from a wide range of environmental waters.

scholarly journals Silicon Effects on the Root System of Diverse Crop Species Using Root Phenotyping Technology

Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 885
Author(s):  
Pooja Tripathi ◽  
Sangita Subedi ◽  
Abdul Latif Khan ◽  
Yong-Suk Chung ◽  
Yoonha Kim
Keyword(s):  
Root System ◽  
Root Morphology ◽  
Morphological Traits ◽  
Crop Production ◽  
Spatial Configuration ◽  
Global Climate ◽  
Learning Technologies ◽  
Climate Change Scenarios ◽  
Crop Species ◽  
Wide Range

Roots play an essential function in the plant life cycle, as they utilize water and essential nutrients to promote growth and plant productivity. In particular, root morphology characteristics (such as length, diameter, hairs, and lateral growth) and the architecture of the root system (spatial configuration in soil, shape, and structure) are the key elements that ensure growth and a fine-tuned response to stressful conditions. Silicon (Si) is a ubiquitous element in soil, and it can affect a wide range of physiological processes occurring in the rhizosphere of various crop species. Studies have shown that Si significantly and positively enhances root morphological traits, including root length in rice, soybean, barley, sorghum, mustard, alfalfa, ginseng, and wheat. The analysis of these morphological traits using conventional methods is particularly challenging. Currently, image analysis methods based on advanced machine learning technologies allowed researchers to screen numerous samples at the same time considering multiple features, and to investigate root functions after the application of Si. These methods include root scanning, endoscopy, two-dimensional, and three-dimensional imaging, which can measure Si uptake, translocation and root morphological traits. Small variations in root morphology and architecture can reveal different positive impacts of Si on the root system of crops, with or without exposure to stressful environmental conditions. This review comprehensively illustrates the influences of Si on root morphology and root architecture in various crop species. Furthermore, it includes recommendations in regard to advanced methods and strategies to be employed to maintain sustainable plant growth rates and crop production in the currently predicted global climate change scenarios.

Experimental Study of Static Friction in a Spherical Elastic-Plastic Contact

2008 ◽  
Author(s):  
Andrey Ovcharenko ◽  
Gregory Halperin ◽  
Izhak Etsion
Keyword(s):  
Friction Force ◽  
Normal Load ◽  
Static Friction ◽  
Tangential Displacement ◽  
Accurate Identification ◽  
Elastic Plastic ◽  
Static Friction Coefficient ◽  
Wide Range ◽  
Material Good ◽  
Contact Diameter

The elastic-plastic contact between a deformable sphere and a rigid flat during pre-sliding is studied experimentally. Measurements of friction force and contact area are done in real time along with an accurate identification of the instant of sliding inception. The static friction force and relative tangential displacement are investigated over a wide range of normal preloads for several sphere materials and diameters. It is found that at low normal loads the static friction coefficient depends on the normal load in breach of the classical laws of friction. The pre-sliding displacement is found to be less than 5 percent of the contact diameter, and the interface mean shear stress at sliding inception is found to be slightly below the shear strength of the sphere material. Good correlation is found between the present experimental results and a recent theoretical model in the elastic-plastic regime of deformation.

scholarly journals Angolan vegetable crops have unique genotypes of potential value for future breeding programmes

2016 ◽  
Vol Volume 112 (Number 3/4) ◽  
Author(s):  
José P. Domingos ◽  
Ana M. Fita ◽  
María B. Picó ◽  
Alicia Sifres ◽  
Isabel H. Daniel ◽  
...  
Keyword(s):  
Strong Dependence ◽  
The Other ◽  
Vegetable Crops ◽  
Cucurbita Maxima ◽  
Capsicum Chinense ◽  
Local Markets ◽  
Potential Value ◽  
Wide Range ◽  
Different Types ◽  
Breeding Programmes

Abstract A survey was carried out in Angola with the aim of collecting vegetable crops. Collecting expeditions were conducted in Kwanza-Sul, Benguela, Huíla and Namibe Provinces and a total of 80 accessions belonging to 22 species was collected from farmers and local markets. Species belonging to the Solanaceae (37 accessions) and Cucurbitaceae (36 accessions) families were the most frequently found with pepper and eggplant being the predominant solanaceous crops collected. Peppers were sold in local markets as a mixture of different types, even different species: Capsicum chinense, C. baccatum, C. frutescens and C. pubescens. Most of the eggplant accessions collected belonged to Solanum aethiopicum L. Gilo Group, the so-called ‘scarlet eggplant’. Cucurbita genus was better represented than the other cucurbit crops. A high morphological variation was present in the Cucurbita maxima and C. moschata accessions. A set of 22 Cucurbita accessions from Angola, along with 32 Cucurbita controls from a wide range of origins, was cultivated in Valencia, Spain and characterised based on morphology and molecularity using a set of 15 microsatellite markers. A strong dependence on latitude was found in most of the accessions and as a result, many accessions did not set fruit. The molecular analysis showed high molecular variability and uniqueness in the collected accessions, as shown by their segregation from the set of global controls. In summary, the material collected is quite valuable because of its uniqueness and the potential of the breeding characteristics it possesses.

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