Annals of Agrarian Science最新文献

Improving productivity and farm income is the challenge for the grower in rice cultivation. Therefore, a series of on-farm field experiments were conducted to evaluate comparative performance of different nutrient management practices in boro rice production in south central coastal region of Bangladesh. The performance of high yielding rice varieties were tested with four fertilizer management options, viz. (i) use of Rice Crop Manager (RCM), (ii) Soil Test Based (STB) fertilizer application, (iii) BRRI Recommended Fertilizer (BRF) application, and (iv) Farmers' Fertilizer Practice (FFP). Fertilizer management practices and variety interacted significantly to influence yield components like panicle m⁻², grains panicle⁻¹ and 1000-grain weight of rice. Similarly, grain yield of rice also significantly varied with the interaction of fertilizer management and rice varieties. Application of BRF produced maximum grain yield of boro rice. However, the grain yield produced with RCM was comparable with that of BRF management. The RCM involved lower fertilizer cost than that of BRF and FFP. Hence, the gross return and profit of rice obtained from RCM was similar with that in BRF. The cost dominant analysis confirmed that RCM was economic and profitable fertilizer management practices in southern Bangladesh.

The aim of this work was to study and define the example of one pond fisheries of the Republic of glugеosis distribution of fish; the species composition of fish, affected by the causative agent of the disease; the intensity and extensity of invasion, and pathways of the pathogen into the territory of our Republic. Based on the results of the conducted research we can conclude that in pond farms of the Republic entered a new parasitic disease glugeosis, that threatens the successful development of pond fish farming. The most sensitive to infection with this disease is a subspecies of rainbow trout.

Plants are sessile and have to face the adaptation to various biotic as well as abiotic stress management. Plants are also capable to produce new organs and tissues throughout the course of their life to sustain its existence. Therefore, the plant needs precise and competent mechanisms of gene regulation in stress management as well as in growth and development. Epigenetics play a significant role in regulating gene expression and here, the recent significant advancements in plant epigenetics, from growth and development to stress management are being reviewed. The epigenetic-based programming in plants under biotic and abiotic stresses as well as during growth and development is carried out by methylation-demethylation, acetylation-deacetylation and small RNAs, which are involved in the regulation of gene expression without any change in the DNA sequences. Such review would be helpful to better understand the plants' epigenetics approaches under various stresses as well as for growth and developmental stages to enhance the plant tolerance and resistance against biotic and abiotic stresses and crop production by reprogramming gene regulation. It would also elaborate the recent epigenetics advancements in plants.

Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae), an agricultural pest originating from Southeast Asia, has been recorded for the first time in the Caucasus and may threaten crops within the region. In 2016, two introduced species, the Brown Marmorated Stink Bug – Halyomorpha halys Stal (Hemiptera: Pentatomidae) and the Buxus moth – Cydalima perspectalis (Walker) (Lepidoptera: Crambidae), were considered the most dangerous pest species in western Georgia and spreading rapidly east. Because the Spotted Wing Drosophila has only been recently recorded, its damage is not yet known.

The presented work concerns studying a possibility of using blue-green alga (cyanobacteria) Spirulina for cleaning water polluted with DDT (1,1'-(2,2,2-trichloroethane-1,1-diyl)bis (4-chlorobenzene)). For this aim, at first the influence of different concentrations of DDT (1, 10 and 50 ppm) on the ability of growing of Spirulina and the intensity of uptake of DDT by blue-green alga have been investigated. In parallel, the penetration of tested toxicant into Spirulina cells and the influence on cell ultrastructure by using electron microscopic method have been studied. The obtained results show that DDT easily penetrated Spirulina cells and caused partial destruction of organelles. According to obtained data, 10 ppm is acceptable concentration of DDT for Spirulina growing in polluted water. Finally, the model large-scale experiment in reservoir with volume 40 L for testing possibility of using Spirulina to clean artificially polluted water have been carried out. The obtained results have been shown that after 15 days of incubation Spirulina removes approximately 70% of DDT from polluted water. These results can become a basis for development of a new phytoremediation technology for cleaning of DDT-polluted waters based on application of Spirulina.

Georgian oak (Quercus iberica Stev.) is basically prevailed in moderately warm and dry climate zones of Eastern Georgia. Georgian oak naturally grows at elevations of 500–1000 m above sea level, it can reach 1400 m on the southern exposure slopes. Oak forests in Georgia are presented in the form of single and mixed stands. In total, in the living biomass of oak forests of Georgia 10,324 Tg C are accumulated, 7765 Tg C (75.2%) of this amount accounts for the aboveground biomass, and 2559 Tg C (24.8%) for the belowground biomass. 0.616 Tg of carbon are accumulated in the dead standing trees and fallen deadwood of the oak forests. The carbon stock per unit area attains to 2.48 t/ha. Forest dead cover - 0,637 Tg C (2.6 t/ha). Soil - 23,480 Tg C (94.6 t/ha). In the oak dominated forests of Georgia 35.06 Tg C are accumulated that correspond to 128.6 Tg CO₂, absorbed from the atmosphere. In the process of air exchange, oak dominated forests spread in Georgia on 248313 ha annually absorb from the atmosphere 565 Gg CO₂ on average and release in the atmosphere 438 Gg O₂.

A prospecting of habitats and mechanical support host species for the climber Eurasian wild grapevine, Vitis vinifera L. subsp. sylvestris (Gmelin) Hegi, was carried out on 13 natural populations situated along river bank forests, floodplains and colluvial positions in Georgia (Marneuli, Mtskheta and Gori districts, Gardabani Protected area and Lagodekhi Reserve), Armenia (Akhtala and Tavoush regions) and Azerbaijan (Quba region) during survey of 2013. The research demonstrated that Eurasian wild grapevine (Vitis vinifera subsp. sylvestris) is found in Southern Caucasus in a wide variety of habitats always linked to water availability. Punica granatum trees are the commonest mechanical support for wild grapevine in the South Caucasus and Hedera helix often shares the same support trees. However we documented wild grapevines climbing on other 24 different species of trees and large shrubs and, further, 32 associated species. We determined, four different clusters of localities using Structure software and the Weighted Neighbor Joining tree. These clusters are characterized by specific mechanical support and accompanying species. Other vines competing for host with Eurasian wild grapevine belong to the genera Clematis, Hedera, Humulus, Smilax and Vitis ssp.

The genotype × environment interaction (GxE) is a serious problem when comparing the performance of crop genotype across environments because it reduces the efficiency of the genetic gain through selection. GxE is said to occur when the relative performance of the crop genotype is not consistent from one environment to another. The purpose of the study is to use genotype-focused scaling for genotypic comparison and environment-focused scaling for environmental comparison. Yield data component were determined from 20 accessions of Cowpea from Nigeria across two locations during year 1 and year 2 planting seasons to study the effect of environment on genotype. Ten quantitative traits were analyzed and yield component, such as weight of seed in pod, weight of 100 seed/plant, number of seed/pod, pod length, and number of pods/plant, were measured and subjected to statistical analysis. From the result obtained, there were significant differences in weight of seed in pod, weight of 100 seed/plant, number of seed/pod, pod length, and number of pods/plant, having 0.084, 11.638, 13.182, 9.390, and 51.911 at P ≤ 0.01 across the two locations. The study revealed a significant effect of environment on yield component among the genotypes. However, the most stable genotypes across the two locations were NG/SA/07/083, NG/SA/DEC/07/035, and NG/SA/07/0042.

Passion fruit (Passiflora edulis [Sims]) is currently ranked third among fruit exports from Kenya and has great potential since demand for both fresh fruit and processed juice is on a continuous increase. Although assessment of genetic variability of germplasm is indispensable for improvement and development of superior cultivars, little information is available on the genetic diversity of passion fruit cultivated in Kenya. The objective of this study was to determine the genetic diversity of passion fruit genotypes from major growing regions in Kenya using sequence-related amplified polymorphism (SRAP) markers. Twenty four SRAP primer combinations were screened using three passion fruit genotypes and only seven that displayed polymorphic and stable amplification profiles were used to analyze 22 genotypes. The seven primer combinations amplified a total of 931 clear bands with an average of 133 bands per primer pair, of which 610 (65.5%) bands were polymorphic. The similarity coefficients among the 22 passion fruit germplasms ranged from 0.51 to 1.0 with an average of 0.755. The 22 passion fruit genotypes were classified into two groups by cluster analysis using unweighted pair-group method with arithmetic mean (UPGMA) with 12% similarity. Shannon's diversity index was 0.0934 and Nei's gene diversity index was 0.1370 in the present study. The study findings demonstrate the existence of a considerable amount of genetic variability among passion fruit genotypes grown in different regions of Kenya. This indicates the potential application of these genotypes in breeding programs by exploiting the use of molecular markers for selection of specific agronomic traits.

Degradation of soil due to unsuitable land management practices is a chief impairment of optimum land productivity. The spatial variability of soil properties is needed for agricultural productivity, food safety and environmental modeling. The present study was conducted in lateritic soils of West Bengal, India to understand the spatial variability of soil properties using a geostatistical model. Nitrogen (N), soil pH, electrical conductivity (EC), Phosphorus (P), Potassium (K) and organic carbon (OC) were measured. Surface maps of soil properties were prepared using the semivariogram model through Kriging techniques. A positive correlation was observed between OC and N. The Quantile-quantile plots showed a normal distribution of EC, K, pH, N, and OC. The value for nugget/sill of K, N, and EC were 0.25–0.75 indicating moderate spatial autocorrelation among the variables. Phosphorus (P) was highly concentrated in the eastern part, whereas the agglomeration of higher EC was found in the north east and south west corner of the study site. The cross validation results illustrated the smoothing effect of the spatial prediction. The present study suggests that the geostatistical model can directly reveal the spatial variability of lateritic soils and will help farmers and decision makers for improving soil-water management.