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The demand for more sustainable farming is driving interest in alternative cropping systems, such as strip intercropping. In such systems, two or more crops are grown simultaneously on the same field, offering advantages such as increased biocontrol of weed, pest, diseases, and increasing productivity in resource-limited ecosystems. However, with strip intercropping, complexity increases and quantitative data to study the competition between plants are still limited due to the current manual process of acquiring data. While individual-plant data would facilitate this study, the manual acquisition is not feasible for large-scale experiments. Alternatively, unmanned aerial vehicles (UAV) equipped with high-resolution camera can cover large areas and estimate individual-plant growth from RGB imagery using automated image-processing methods. This study investigated its applicability to monitor the plant-height development of individual cabbage plants in space and time with sufficient accuracy and to identify the potential differences between strip intercropping treatments. Using RGB imagery and structure-from-motion analysis, a digital surface model (DSM) was created. Individual plant-height was calculated from the DSM by estimating the height of the vegetation and the height of the soil. Comparing the height estimations with ground-truth height measurements showed an overall root mean square error (RMSE) of 4.67 cm, which is in the same range as the 4 cm standard deviation between measurements of multiple observers. The UAV-based height estimation of individual plants was used not only to compare the development in a strip intercropping field to that in a monoculture but also to compare with various treatments in the strip intercropping system. The results show that the plants grew faster in intercropping conditions than in monocropping conditions, with a subtle difference between treatments. Our results illustrate that with a UAV-based imaging approach we can go beyond current experimental practice and collect vast amounts of data on individual plants with high spatial and temporal resolution with an accuracy similar to that of manual measurements.

O efeito da embebição de sementes de algodão cultivar IPR-120 com cloreto de mepiquat no crescimento e desenvolvimento inicial das plantas foi avaliado em casa de vegetação. Os tratamentos foram arranjados em esquema fatorial 5x3 (cinco concentrações do produto, três tempos de embebição), com cinco repetições. Altura e área foliar foram avaliadas, da emergência até o início do florescimento. Os tratamentos com cloreto de mepiquat reduziram a altura da planta desde a emergência, com interações entre os fatores analisados. O número de botões florais e de ramos, a área foliar, a matéria seca da parte aérea e a altura da inserção do nó cotiledonar também foram reduzidos pelos tratamentos.The effects of cotton seeds cultivar IPR-120, soaked with mepiquat chloride solutions on the initial growth and development of the plants, grown in 2,5 L plastic bags, were evaluated under greenhouse conditions. Treatments comprised five mepiquat chloride concentration solutions and three soaking durations, with five replications. Evaluations were carried out weekly from emergence to beginning of flowering stage. The treatments containing mepiquat chloride soaking reduced plant height since the emergence, with some interactions among the factors. They also reduced the number of flower buds and branches, leaf area, dry matter and the height of the cotyledon node.

In our research project under cultivation we examined 4 cultivars ('Soroksári 40', 'Lutea , 'Goral', 'Bona') and 28 wild populations of chamomile assuring all of them the same environmental conditions. Plant height, flower-diameter, essential-oil content, and the main terpenoid and flavonoid composition were analysed. The aim of our study was to establish the genetic background of breeding a new cultivar as well as encircle those natural habitats that give chamomile drug with the best quality. In the case of plant height populations from the Great Hungarian Plain were lower than plants from Transdanubia and the control cultivars. Between the wild and the standard individuals we found significant differences with relevance to the flower-diameter. With regard to the essential oil content the populations were very heterogeneous even those, which came from the same habitat. Populations form Transdanubia and Nagyiván reached the essential oil level of the cultivars (0.721-0.931 gi100g), and 75% of the examined plants exceeded the minimum requirement of the PhHg VIII. According to the essential oil composition our previous statement was confirmed that in the populations of Transdanubia and Northern part of Danube—Tisza Mid Region the main component is bisabolol-oxide A (30-41.2%), while plants native to the territory cast of the river Tisza are mainly characterised by a-bisabolol (32.3-48.4). In some samples the ratio of bisabolol-oxide B was more than 10%. The chamazulene content was higher in the cultivars selected to this component (above 20%), than in the wild populations (varied between 1.22 and 17.2%). Populations originated from the central part of Hortobágy region had extremely high apigenin content (10-13 mg/g), but in the case of chlorogenic acid, hyperoside and quercitrin we did not find any differences affected by the origin.