Cultivated Fields Research Articles

Geospatial analysis of Musa acuminata cultivation using multi-temporal remote sensing – Uthal Balochistan

Climate change has made researchers realize there is a need to focus on crops consumed staple, including fruits.Uthal is the districts headquarter of Lasbela and has long been known for its valuable banana production. Due to scarcity of rainfall, aquifers are not recharging significantly, causing slow decrease in the Musa acuminate (common name banana) crop. Banana is a significant source of earnings for local cultivators. The primary objective of the present study is the fluctuation assessment of banana cultivation of Uthal. The methodology has been designed in three steps. The first was ground-truthing with the help of GPS survey of banana cultivation areas, the second, classification of greenery and banana crops based on Landsat 8 images via EVI and NDVI remote sensing tools. The third and last step was combined both data along with government published data for the accuracy assessment of banana cultivation areas. As per extracted results from NDVI, the share of banana total cultivated land of the study area has declined concerning the overall cultivated land of the study area which reduced from 1115 to 879 ha between 2013 and 2022. Results identified that the EVI-NDVI-GPS model is more significant for monitoring agricultural activities. The present study is an advanced contribution to the scientific field of Banana cultivation in Uthal.

Sunflower-YOLO: Detection of sunflower capitula in UAV remote sensing images

Accurate identification and monitoring of sunflower capitula are crucial for field phenotypic analysis, cultivation management, phenological monitoring, and yield prediction. Manual observation, however, faces significant challenges due to the complexity of field environments and the morphological diversity of sunflower capitula. Unmanned Aerial Vehicles (UAVs) have emerged as an ideal platform for monitoring sunflower capitula due to their low cost and high spatiotemporal resolution. This study introduces Sunflower-YOLO, an enhanced model based on YOLOv7-tiny, designed for detecting sunflower capitula in UAV remote sensing images. The model effectively identifies sunflower capitula and distinguishes between three specific states: open, half-open, and bud. Sunflower-YOLO incorporates several key improvements: the SiLU activation function replaces the original LeakyReLU, enhancing the model’s nonlinear expression capability; a shallow high-resolution feature map and an additional detection head for small targets are introduced during the feature fusion stage to improve the detection performance of small capitula; and the integration of deformable convolution and the SimAM attention mechanism enhances the ELAN structure in the backbone, creating a new DeformAtt-ELAN structure that improves the model’s ability to capture morphological variations and reduces noise interference. Experimental results demonstrate that Sunflower-YOLO achieves precision, recall, and mAP@0.5 of 92.3 %, 89.7 %, and 93 %, respectively, marking improvements of 4.2 %, 4.2 %, and 3.7 % over the original YOLOv7-tiny model. The average precision (AP) for the three growth states is 98.7 %, 93.4 %, and 87 %, with AP for the half-open and bud states improving by 6.5 % and 4.7 %, respectively. The model’s FLOPs is 17.7 G, its size is 13.8MB, and it achieves an FPS of 188.52. Compared to current mainstream state-of-the-art (SOTA) models for object detection, Sunflower-YOLO achieves the highest mAP@0.5 in detecting multiple types of sunflower capitula. The constructed capitulum density map offers a practical view for observing sunflower growth status. This study highlights the immense potential of combining UAV remote sensing technology with YOLO object detection algorithms in monitoring sunflower capitula and their growth processes, providing an innovative and effective approach for precision agriculture practices.

Identification of new phylogenetic lineage of Lasiodiplodia causing leaf spot and tip necrosis causing agent on Aloe vera in Sri Lanka and screening eco-friendly control measures

Aloe vera, a member of the Asphodelaceae family, is renowned globally for its medicinal properties and widespread applications in cosmetics, pharmaceuticals, and food production. In Sri Lanka, both cultivated and wild A. vera are susceptible to leaf spot and tip necrosis. The present aims to identify the causative agent of this disease and screen the effectiveness of various natural substances in disease control. Disease incidence was assessed in both cultivated fields and wild habitats, and the results showed a higher percentage in the wild. Isolates obtained from symptomatic leaves were identified as members of Lasiodiplodia based on morphological studies. The phylogenetic analysis, which combined sequences from the Internal Transcribed Spacer (ITS) region and a segment of the calmodulin (cmdA) gene, suggested that the isolates might represent a new lineage within the genus Lasiodiplodia. These isolates appeared to share a common ancestor with Lasiodiplodia hormozganensis. Koch's postulates validated the pathogenicity of the isolates. Natural substances, namely marine algal extracts, plant extract and cell-free supernatants (CFSs) of bacteria, were tested against the isolates. CFSs of Pseudomonas fluorescens and Bacillus megaterium showed significantly higher inhibition on conidial germination compared to the tested commercial fungicide. Further, CFS of P. fluorescens revealed the notable effectiveness on the development of leaf spot and tip necrosis on the leaf compared to the tested fungicide. These findings underscore the potential of P. fluorescens CFS in managing A. vera diseases caused by the isolates of Lasiodiplodia in Sri Lanka.

Comparison of fish biological indicators of Clarias gariepinus hybrids grown in ras and pond farming conditions

To improve technologies in the field of commercial cultivation of aquaculture objects and further development of the warm-water aquaculture sector in Russia, we previously undertook breeding methods and approaches to obtain high-quality planting material for a promising commercial object — the African catfish Clarias gariepinus. This article presents, in a comparative aspect, the experience of growing hybrid offspring of African catfish, obtained from crossing two breeds — Mikhailovskaya and Tamanskaya, in a closed water supply system and in a pond farm in the Astrakhan region in the summer. It was shown that hybrid individuals of clariid catfish bred in a pond farm during the feeding period under consideration (from July to September) were characterized by a high specific growth rate and low feed ratio compared to hybrids grown in a recirculation system, respectively, 11.4% versus 9.87% and 0.96 versus 1. Also, based on the results of fishing, over two months of cultivation in a pond farm, hybrids of clariid catfish increased the total biomass by 13 times, while in a recirculating system it increased by 15 times, but the final biomass of fish turned out to be greater when reared in open reservoir (46.875 versus 10.87 kg). It was shown that the final individual mass of hybrid fish cultured in pond conditions was 11.0% higher than the final mass of individuals in the recirculation system. The conducted studies showed that in the climatic conditions of the Astrakhan region (VI fish-breeding zone), a promising direction for aquaculture of African catfish is the feeding cultivation of hybrid juveniles in pond farms. It should be taken into account that in order to obtain marketable fish products (i.e. individuals weighing over 1000 g), it is necessary to use fish seeding material with an average weight of at least 100 g.

Effects of Different Tillage Years on Soil Composition and Ground-Dwelling Arthropod Diversity in Gravel-Sand Mulching Watermelon Fields

Arthropods play a crucial role in ecological processes and agricultural productivity. Soil physicochemical properties, indicators of soil health, are closely linked to arthropod communities. Gravel-sand mulching, commonly employed in arid farming, initially enhances water retention and temperature regulation but may contribute to land degradation with prolonged use. This study investigated how varying tillage durations affected soil properties and arthropod diversity under gravel-sand mulching. The analysis employed multiple comparison methods, covariance analysis (ANCOVA), non-metric multidimensional scaling (NMDS), and redundancy analysis (RDA). The results indicated that while soil fertility was better preserved in cultivated fields compared to in the desert grassland, arthropod diversity significantly decreased with longer cultivation periods. A total of 1099 arthropods from 79 species were sampled, by Barber trap. The highest diversity was observed in native grassland (NG), with 305 arthropods from 39 species, while tillage 21 years (GPS-21Y) exhibited the lowest diversity, with only 103 arthropods from 6 species. Dominant species included the carnivores Labidura japonica and Cataglyphis aenes. The analysis revealed low similarity in arthropod communities between GPS-21Y and other fields and high similarity in soil physicochemical properties between NG and the transition zone (STZ). RDA showed available potassium (APP) was negatively correlated with arthropod species diversity and concentration, total Nitrogen (TN) was positively correlated with arthropod species diversity but negatively correlated with species concentration, total phosphorus (TP) was negatively correlated with arthropod species diversity and concentration. This study provides insights into the relationship between maintaining soil fertility and supporting arthropod diversity in grassland agriculture. While soil fertility and arthropod diversity were correlated, continuous cropping practices negatively impacted arthropod diversity, offering valuable information for pest management and sustainable agricultural practices.

Screening of soil bacteria from cotton cultivated fields reveals actinobacteria as the main group of isolates with antagonistic activity against the oomycete Pythium ultimum in vitro

Screening of soil bacteria from cotton cultivated fields reveals actinobacteria as the main group of isolates with antagonistic activity against the oomycete Pythium ultimum in vitro

Novel antimicrobial polysaccharide hydrogel with fertilizer slow-release function for promoting Sesamum indicum L. seeds germination

The problem of seed germination is one of the important scientific and technological issues facing the field of agroforestry cultivation, and the germination process requires both sufficient water and certain nutrients. The high solubility of fertilizers and pesticides makes their utilization inefficient, while water resources are costly in difficult standing environments. This article innovatively provides the preparation of hydrogels with slow-release function by using cellulose and chitosan as substrates, which have high water retention capacity and long-lasting fertilizer release (CCH/PVA/NCC/NPK). In this study, cellulose chitosan hydrogel (CCH) with 50 wt% of chitosan, 1 wt% of polyvinyl alcohol solution (PVA), 0.5 wt% of nanocellulose solution (NCC), and 2.5 wt% of nitrogen, phosphorus, and potassium (NPK) solution were used in optimized conditions to successfully prepare hydrogel materials with swelling as high as 79 g g−1 of CCH/PVA/NCC/NPK. Under neutral conditions, CCH/PVA/NCC/NPK has the slowest water release rate and the strongest water retention capacity, and it can greatly reduce the amount of fertilizers and the consumption of water resources, and it has a wide range of applications and prospects for development.

Diverse biological communities promote SOM molecular diversity and compositional transformations during natural fallow stage in paddy fields

Monoculture cultivation patterns in agro-ecosystems only provide less varied soil organic matter (SOM) molecules of plant origin. Whether and how the natural fallow stage between cultivation seasons facilitates the restoration of SOM molecular diversity and mitigates the adverse impacts of constant cropping pattern is elusive. Here, we utilized FT-ICR-MS, UHPLC-MS/MS, and high-throughput sequencing to investigate the biological change processes in SOM molecular composition under cultivation and fallow status in a long-farmed paddy field. Our study showed that SOM molecular diversity increased by 45.70%–85.36% in fallow stage compared to rice cultivation season. SOM molecular diversity was positively correlated with bacterial diversity and root exudate molecular diversity, and negatively correlated with fungal diversity. Notably, root exudate molecular diversity accounted for 48.48% of the variation in SOM molecular diversity. The increased SOM molecular diversity in fallow stage was attributed more to the diverse plant-produced molecules than the microbe-consumed molecules. Plant species turnover resulted in the conversion of root exudate components to Organoheterocyclic compounds and Organic acids/derivatives from rice planting stage to fallow stage. Recruited microbes were dominated by Basidiomycita, Ascomycota, Acidobacteria, Chloroflexi and Proteobacteria, resulting in the transformation from carbohydrates, lipid-like SOM molecules to lipid-like and lignin-like SOM molecules. Both field and microcosm experiments confirmed that root exudates are the main source of SOM molecules, and are influenced by the soil microbial community. This study provides solid evidence that fallow status in agro-ecosystems provides explosion of biodiversity and counteracts the negative effects of long-term monoculture cultivation on SOM diversity.Graphical

Transcriptome analysis of the common moss Bryum pseudotriquetrum grown under Antarctic field condition.

Mosses are distributed all over the world including Antarctica. Although Antarctic mosses show active growth in a short summer season under harsh environments such as low temperature, drought and high levels of UV radiation, survival mechanisms for such multiple environmental stresses of Antarctic mosses have not yet been clarified. In the present study, transcriptome analyses were performed using one of the common mosses Bryum pseudotriquetrum grown under an Antarctic field and artificial cultivation conditions. Totally 88205 contigs were generated by de novo assembly, among which 1377 and 435 genes were significantly up and downregulated, respectively, under Antarctic field conditions compared with artificial cultivation conditions at 15°C. Among the upregulated genes, a number of lipid metabolism-related and oil body formation-related genes were identified. Expression levels of these genes were increased by artificial environmental stress treatments such as low temperature, salt and osmic stress treatments. Consistent with these results, B. pseudotriquetrum grown under Antarctic field conditions contained large amounts of fatty acids, especially α-linolenic acid, linolenic acid and arachidonic acid. In addition, proportion of unsaturated fatty acids, which enhance membrane fluidity, to the total fatty acids was also higher in B. pseudotriquetrum grown under Antarctic field conditions. Since lipid accumulation and unsaturation of fatty acids are generally important factors for the acquisition of various environmental stress tolerance in plants, these intracellular physiological and metabolic changes may be responsible for the survival of B. pseudotriquetrum under Antarctic harsh environments.

A cradle-to-customer life cycle assessment case study of UK vertical farming

Global population rise, increased rural to urban migration, climate change and conflict have placed strain on global trade and food supply chains. Vertical farming (VF) is a relatively novel method for cultivating many fresh fruits and vegetables, and often is claimed to have lower environmental impacts than field cultivation. However, to date there are few studies utilising primary data which have evaluated the environmental impact VF may have. This study utilised Life Cycle Assessment (LCA) to evaluate the environmental impact of lettuce production in a commercial vertical farm in the UK. This was compared with data from the literature on the impacts of lettuce in field cultivation. Scenarios were also examined to evaluate the impact of VF systems with varying electricity sources, and waste, water and nutrient management options. The VF was found to have a similar or lower Climate Change impact than field cultivation, depending on energy source used. VF had a slightly higher environmental impact than field cultivation in some other environmental impact categories such as freshwater eutrophication potential and acidification potential. Electricity demand and the medium used for ‘plugs’ in the VF were found to be the main hotspots of the system. The results of this study provide insights on the environmental impact and resource efficiency of VF, feasibility for larger scale deployment, and provide further empirical evidence to support the claims made previously in the literature.

Development of universal working bodies for cultivators in inter-row processing of cotton

Abstract The development of multifunctional universal working bodies that can perform various functions with quick and uncomplicated adjustment, low energy and material consumption, and ensure high-quality processing of row spacing throughout the entire growing season of plants is in high demand. The project documents were developed for mastering the production of a cultivator with a universal working body and were introduced into the design process at BMKB-Agromash JSC. As a result, a universal working body was developed and installed on the beam of the KXU-4B cultivator, featuring quick and easy adjustment and low metal consumption. The use of a cotton cultivator equipped with universal working bodies in inter-row processing of cotton is expected to reduce labor costs by 16.0%, exploitation costs by 15.56%, and metal consumption of the aggregate by 1.23 times, as well as fuel consumption per hectare of cultivated field by 11.26%. To achieve this, a universal working body was designed that performs all technological operations typically performed by multiple working bodies mounted on existing cultivators without compromising quality. The universal working body is equipped with a wide right and left blade, allowing for the cultivation of the middle of the cotton row, slopes, and weed cutting. The result is a constructive scheme of a universal working body, where working parts are concentrated in one column, enabling the performance of technological operations during different vegetative seasons.

Analysis of Physiological and Biochemical Parameters in the Radish (Raphanus sativus L.) Obtained in Different Cultivation Systems

This paper presents the results obtained from the analysis of physiological and biochemical parameters in the radish, species Raphanus sativus L., variety Rond Ecarlate, which was grown in three different systems (in the field, in the solarium and in the climate chamber). Several parameters necessary for the evaluation of biomass, physiological processes and nutritional values were determined. Regarding the biometric parameters, it was noticed that in the field cultivation the plants formed 11-12 leaves, in the solarium average 12-13 leaves, and in the climatic chamber the analyzed plants formed 7-9 leaves, on an average. The total biomass of the plant was recorded with the following average values: in the field 70.05 grams, in the solarium 92.3 grams and in the climate chamber 32.9 grams. Regarding the circumference of the tuberous hypocotyl axis, the values are higher in plants grown in solarium (16.9 cm), with the smallest dimensions being recorded in plants grown in the climate chamber (7.2 cm). The highest average pulp firmness value was observed in plants grown in the solarium (0.27 kg force), and the lowest values were seen in plants grown in the climate chamber (0.14 kg force). Regarding the amount of water lost through perspiration by the leaves of radish plants, the highest average values were recorded at plants grown in the solarium, and the lowest at plants grown in the climatic chamber. The average soluble dry matter content was higher (over 4%) in plants grown in the climate chamber compared to other harvesting systems. The analysis of the average carbohydrate content shows that the total soluble carbohydrates were present only in the hypocotyl axis and glucose was found both in the hypocotyl axis of the studied plants and in the leaves. Vitamin C was present in variable amounts, both in the hypocotyl axis and in the leaves. The average amino acid content (expressed in amino nitrogen) was between 0.003% and 0.006%. The anthocyanin was present with highest values (54.5 mg) in field-grown plants, and catalase activity was present both in the hypocotyl axis and in the leaves and roots. Air humidity and temperature had a high influence on the development of plant biomass, on the content of dry matter and on the loss of water through transpiration. The biometric, physiological and biochemical parameters varied depending on the cultivation system.

Challenges and Opportunities in the Sustainable Improvement of Carrot Production.

From an agricultural perspective, carrots are a significant tap root vegetable crop in the Apiaceae family because of their nutritional value, health advantages, and economic importance. The edible part of a carrot, known as the storage root, contains various beneficial compounds, such as carotenoids, anthocyanins, dietary fiber, vitamins, and other nutrients. It has a crucial role in human nutrition as a significant vegetable and raw material in the nutraceutical, food, and pharmaceutical industries. The cultivation of carrot fields is susceptible to a wide range of biotic and abiotic hazards, which can significantly damage the plants' health and decrease yield and quality. Scientific research mostly focuses on important biotic stressors, including pests, such as nematodes and carrot flies, as well as diseases, such as cavity spots, crown or cottony rot, black rot, and leaf blight, caused by bacteria, fungi, and oomycetes. The emerging challenges in the field include gaining a comprehensive understanding of the interaction between hosts and pathogens in the carrot-pathogen system, identifying the elements that contribute to disease development, expanding knowledge of systemic treatments, exploring host resistance mechanisms, developing integrated control programs, and enhancing resistance through breeding approaches. In fact, the primary carrot-growing regions in tropical and subtropical climates are experiencing abiotic pressures, such as drought, salinity, and heat stress, which limit carrot production. This review provides an extensive, up-to-date overview of the literature on biotic and abiotic factors for enhanced and sustainable carrot production, considering the use of different technologies for the shelf-life extension of carrots. Therefore, it addresses the current issues in the carrot production chain, opening new perspectives for the exploration of carrots both as a food commodity and as a source of natural compounds.

Impact of Inorganic Fertilizer and Organic Manure on Physico-chemical Properties of Soil in Pea (Pisum sativum. L) Cultivated Field

Impact of Inorganic Fertilizer and Organic Manure on Physico-chemical Properties of Soil in Pea (Pisum sativum. L) Cultivated Field

Characteristics of the Perianthic Endophytic Fungal Communities of the Rare Horticultural Plant Lirianthe delavayi and Their Changes under Artificial Cultivation.

Flower endophytic fungi play a major role in plant reproduction, stress resistance, and growth and development. However, little is known about how artificial cultivation affects the endophytic fungal community found in the tepals of rare horticultural plants. In this research, we used high-throughput sequencing technology combined with bioinformatics analysis to reveal the endophytic fungal community of tepals in Lirianthe delavayi and the effects of artificial cultivation on the community composition and function of these plants, using tepals of L. delavayi from wild habitat, cultivated campus habitat, and cultivated field habitat as research objects. The results showed that the variety of endophytic fungi in the tepals of L. delavayi was abundant, with a total of 907 Amplicon sequencing variants (ASVs) obtained from all the samples, which were further classified into 4 phyla, 23 classes, 51 orders, 97 families, 156 genera, and 214 species. We also found that artificial cultivation had a significant impact on the community composition of endophytic fungi. Although there was no significant difference at the phylum level, with Ascomycota and Basidiomycota being the main phyla, there were significant differences in dominant and unique genera. Artificial cultivation has led to the addition of new pathogenic fungal genera, such as Phaeosphaeria, Botryosphaeria, and Paraconiothyrium, increasing the risk of disease in L. delavayi. In addition, the abundance of the endophytic fungus Rhodotorula, which is typical in plant reproductive organs, decreased. Artificial cultivation also altered the metabolic pathways of endophytic fungi, decreasing their ability to resist pests and diseases and reducing their ability to reproduce. A comparison of endophytic fungi in tepals and leaves revealed significant differences in community composition and changes in the endophytic diversity caused by artificial cultivation. To summarize, our results indicate that endophytic fungi in the tepals of L. delavayi mainly consist of pathogenic and saprophytic fungi. Simultaneously, artificial cultivation introduces a great number of pathogenic fungi that alter the metabolic pathways associated with plant resistance to disease and pests, as well as reproduction, which can increase the risk of plant disease and reduce plant reproductive capacity. Our study provides an important reference for the conservation and breeding of rare horticultural plants.

Study on the Determination of Flavor Value of Rice Based on Grid Iterative Search Swarm Optimization Support Vector Machine Model and Hyperspectral Imaging.

In the field of rice processing and cultivation, it is crucial to adopt efficient, rapid and user-friendly techniques to detect the flavor values of various rice varieties. The conventional methods for flavor value assessment mainly rely on chemical analysis and technical evaluation, which not only deplete the rice resources but also incur significant time and labor costs. In this study, hyperspectral imaging technology was utilized in combination with an improved Particle Swarm Optimization Support Vector Machine (PSO-SVM) algorithm, i.e., the Grid Iterative Search Particle Swarm Optimization Support Vector Machine (GISPSO-SVM) algorithm, introducing a new non-destructive technique to determine the flavor value of rice. The method captures the hyperspectral feature data of different rice varieties through image acquisition, preprocessing and feature extraction, and then uses these features to train a model using an optimized machine learning algorithm. The results show that the introduction of GIS algorithms in a PSO-optimized SVM is very effective and can improve the parameter finding ability. In terms of flavor value prediction accuracy, the Principal Component Analysis (PCA) combined with the GISPSO-SVM algorithm achieved 96% accuracy, which was higher than the 93% of the Competitive Adaptive Weighted Sampling (CARS) algorithm. And the introduction of the GIS algorithm in different feature selection can improve the accuracy to different degrees. This novel approach helps to evaluate the flavor values of new rice varieties non-destructively and provides a new perspective for future rice flavor value detection methods.

High rhizospheric ammonium levels in Sorghum halepense (johnsongrass) suggests nitrification inhibition potential

AbstractPlants, such as sorghum (Sorghum bicolor), have been shown to secrete root exudates involved in biological nitrification inhibition (BNI), an ability to suppress the conversion of ammonium to nitrate and thereby minimize its loss. Johnsongrass (Sorghum halepense), a weedy relative of cultivated sorghum, may also possess BNI potential, but little is known in this regard. Here, we conducted a field survey at seven different sites in Southeast Texas to determine this evolutionary trait of johnsongrass in different soil environments. It was found that johnsongrass rhizosphere retains high levels (>60%) of ammonium within the total available N (ammonium + nitrate). Furthermore, the degree of ammonium retention by johnsongrass rhizosphere was significantly greater (up to 40%) in the roadside habitat compared to cultivated fields. The high ammonium retention potential by johnsongrass may explain, in part, their persistence and dominance, especially in marginal environments.Core Ideas Nitrogen is a limiting nutrient for plant growth, and nitrification causes loss of nitrogen. Ammonium retention was higher in roadside johnsongrass biotypes compared to that of cropland biotypes. The high rhizoshpheric ammonium retention by johnsongrass may explain, at least in part, its invasiveness. This trait could be further investigated and integrated into modern sorghum cultivars.

Is Klerksdorp die oudste dorp in Transvaal?

This article refutes the claim that Klerksdorp (and not Potchefstroom) is the Transvaal's oldest town, mainly because the assumption that Klerksdorp was founded in 1837 rests upon memory and tradition. It argues moreover that the history of the Great Trek rules out the probability of White settlement in the Western Transvaal before mid-1838. It concludes by indicating that no archival sources or evidence could be traced to prove that a settlement existed at Schoonspruit before March 1840. The settlement which took place there afterwards was basically not a town but a farm. The word erf was not used until the end of the 1840s and indeed referred to arable land or cultivated fields. Although by 1850 the Schoonspruit-settlement did resemble a town and was called Klerksdorp it bore no resemblance to any early Voortrekker dorp. The founding in 1888 of Nuwe Dorp was therefore not merely an extension of Ou Dorp but in fact the establishment of a separate town to provide for the needs of the new gold-diggings at Klerksdorp.

Comparative histology of abscission zones reveals the extent of convergence and divergence in seed shattering in weedy and cultivated rice.

The modification of seed shattering has been a recurring theme in rice evolution. The wild ancestor of cultivated rice disperses its seeds, but reduced shattering was selected during multiple domestication events to facilitate harvesting. Conversely, selection for increased shattering occurred during the evolution of weedy rice, a weed invading cultivated rice fields that has originated multiple times from domesticated ancestors. Shattering requires formation of a tissue known as the abscission zone (AZ), but how the AZ has been modified throughout rice evolution is unclear. We quantitatively characterized the AZ characteristics of relative length, discontinuity, and intensity in 86 cultivated and weedy rice accessions. We reconstructed AZ evolutionary trajectories and determined the degree of convergence among different cultivated varieties and among independent weedy rice populations. AZ relative length emerged as the best feature to distinguish high and low shattering rice. Cultivated varieties differed in average AZ morphology, revealing lack of convergence in how shattering reduction was achieved during domestication. In contrast, weedy rice populations typically converged on complete AZs, irrespective of origin. By examining AZ population-level morphology, our study reveals its evolutionary plasticity, and suggests that the genetic potential to modify the ecologically and agronomically important trait of shattering is plentiful in rice lineages.

Determination of operation performance indicators of unit for mowing crops with the simultaneous incorporation of their stubble into the soil

When harvesting grain crops and forage grasses using a two-phase method, trailed and/or mounted windrowers are usually used. After their passage, stubble remains on the field, which intensively loses soil moisture under sunlight and wind. To reduce these losses, the stubble, along with the soil, is crushed using disc harrows. Due to the use of two sequentially operating units (harvesting and soil-cultivating), their total operating time increases. This does little to preserve soil moisture in the cultivated field. This article provides an example of a more effective solution to this problem. It consists of using one machine-tractor unit instead of two. The proposed combined unit mows an agricultural crop in one working pass and ensures stubble crushing and incorporation into the top layer of soil. The unit consists of a wheeled tractor with a front hitch linkage, a front windrower and a disc harrow mounted behind the tractor. It has been established that the laboriousness of compiling such a unit, considering the tractor's transformation to reverse, is insignificant and amounts to 1442 person-hours. The use of the new unit assists in reducing soil moisture losses. Over a month, it can reach 4.1–5.2% in absolute terms and 15–45% in relative ones. The combined unit movement velocity should be close to 2.5 m s−1 to ensure such a reduction in soil moisture losses. Combining two technological operations performed by one machine-tractor unit does not impair its reliability. At the same time, there is a reduction in processing time for one field by almost half and a decrease in fuel consumption per unit of performed area by 2.25 times.