Формирование густоты стояния растений и урожайности семян сои в условиях Алтайского края

Relevance. Soybean (Glycine max (L.) Merrill is one of the most important protein- oilseed crops in world arable farming. An acute shortage of both food and feed protein is felt in many world’s countries. In this regard, the expansion of soybean seed production is relevant and is dictated by the need for import substitution of both food and feed soybean products.Materials and methods. In the research we studied the influence of two ecologically different cultivation zones: Priobskaya and Prialtaiskaya on the formation of plants density and seed yield of soybean. Three varieties Altom, Gratsia and Pripyat were taken as the objects of the research.Results. On average, over the years of research in full seedlings stage from 60 germinating seeds per square meter (600 thousand pieces/ha), in our experiment, about 56 plants were obtained per 1 m2 or 560 thousand plants per 1 hectare. This means that, on average, 93% of sown seeds give seedlings in field conditions. For harvesting after exposure of soybean crops to numerous biotic and abiotic factors, on average, there are about 52 plants per 1 m² or 520 thousand plants per 1 hectare, that is, 88% of the sown germinating seeds are saved for harvesting and give a yield. The maximum influence on the variability of plant density is exerted by vegetation conditions (years) – 37%. On average, over the years of the study, the maximum yield under Topchikha conditions was obtained in 2019 – 1.9 t/ha – in a year that was distinguished by not hot weather with sufficient rainfall during the growing season. Varieties Gratsia and Pripyat in Smolenskoye conditions significantly exceeded the standard in terms of yield in 2018 and 2020. On average, over the years of research, the Gratsia variety showed itself as more stable with Cv=11.3% in Topchikha conditions and Cv=9.8% in Smolenskoye conditions.Актуальность. Соя (Glycine max (L.) Merrill – одна из важнейших белковомасличных культур в мировом земледелии. Острый дефицит как пищевого, так и кормового белка ощущается во многих странах мира. В связи с этим расширение соевого производства актуально и продиктовано необходимостью импортозамещения пищевой и кормовой соевой продукции.Материал и методика исследований. Изучали влияние двух экологически различных зон возделывания: Приобской (Топчихинский район) и Приалтайской (Смоленский район) на формирование густоты стояния растений и урожайность семян сои. В качестве объектов исследования были взяты три сорта: Алтом, Грация и Припять.Результаты. В среднем за годы исследования в фазу полных всходов из 60 всхожих семян на 1 м² (600 тыс.шт./га) в нашем опыте получали около 56 шт. растений (560 тыс. раст./га. Это означает, что в среднем 93% высеянных семян дают в полевых условиях всходы. К уборке после воздействия на посевы сои многочисленных биотических и абиотических факторов в среднем на 1 м² остаётся 52 растения (520 тыс. шт./га), то есть 88% от высеянных всхожих семян сохраняются к уборке и дают урожай. Максимальное влияние на изменчивость густоты стояния растений оказывают условия вегетации (годы) – 37%. В среднем по годам исследования максимальная урожайность семян в условиях Топчихи была получена в 2019 году (1,9 т/га), который отличался нежаркой погодой с достаточным количеством осадков в период вегетации растений. Сорта Грация и Припять в условиях Смоленского достоверно превзошли стандарт по уровню урожайности в 2018 и 2020 годах. В среднем за годы исследования как более стабильный показал себя сорт Грация с Cv=11,3% – в условиях Топчихи и Cv=9,8% – в условиях Смоленского

Upscaling of solar induced chlorophyll fluorescence from leaf to canopy using the DART model and a realistic 3D forest scene

Non peer reviewe

On the Functional Relationship Between Fluorescence and Photochemical Yields in Complex Evergreen Needleleaf Canopies

Recent advancements in understanding remotely sensed solar‐induced chlorophyll fluorescence often suggest a linear relationship with gross primary productivity at large spatial scales. However, the quantum yields of fluorescence and photochemistry are not linearly related, and this relationship is largely driven by irradiance. This raises questions about the mechanistic basis of observed linearity from complex canopies that experience heterogeneous irradiance regimes at subcanopy scales. We present empirical data from two evergreen forest sites that demonstrate a nonlinear relationship between needle‐scale observations of steady‐state fluorescence yield and photochemical yield under ambient irradiance. We show that accounting for subcanopy and diurnal patterns of irradiance can help identify the physiological constraints on needle‐scale fluorescence at 70–80% accuracy. Our findings are placed in the context of how solar‐induced chlorophyll fluorescence observations from spaceborne sensors relate to diurnal variation in canopy‐scale physiology

Measuring the dynamic photosynthome

Background: Photosynthesis underpins plant productivity and yet is notoriously sensitive to small changes inenvironmental conditions, meaning that quantitation in nature across different time scales is not straightforward. The ‘dynamic’ changes in photosynthesis (i.e. the kinetics of the various reactions of photosynthesis in response to environmental shifts) are now known to be important in driving crop yield. Scope: It is known that photosynthesis does not respond in a timely manner, and even a small temporal “mismatch” between a change in the environment and the appropriate response of photosynthesis toward optimality can result in a fall in productivity. Yet the most commonly measured parameters are still made at steady state or a temporary steady state (including those for crop breeding purposes), meaning that new photosynthetic traits remain undiscovered. Conclusions: There is a great need to understand photosynthesis dynamics from a mechanistic and biological viewpoint especially when applied to the field of ‘phenomics’ which typically uses large genetically diverse populations of plants. Despite huge advances in measurement technology in recent years, it is still unclear whether we possess the capability of capturing and describing the physiologically relevant dynamic features of field photosynthesis in sufficient detail. Such traits are highly complex, hence we dub this the ‘photosynthome’. This review sets out the state of play and describes some approaches that could be made to address this challenge with reference to the relevant biological processes involved

Structural and photosynthetic dynamics mediate the response of SIF to water stress in a potato crop

Solar-induced Fluorescence (SIF) has an advantage over greenness-based Vegetation Indices in detecting drought. This advantage is the mechanistic coupling between SIF and Gross Primary Productivity (GPP). Under water stress, SIF tends to decrease with photosynthesis, due to an increase in non-photochemical quenching (NPQ), resulting in rapid and/or sustained reductions in the fluorescence quantum efficiency (phi F). Water stress also affects vegetation structure via highly dynamic changes in leaf angular distributions (LAD) or slower changes in leaf area index (LAI). Critically, these responses are entangled in space and time and their relative contribution to SIF, or to the coupling between SIF and GPP, is unclear. In this study, we quantify the relative effect of structural and photosynthetic dynamics on the diurnal and spatial variation of canopy SIF in a potato crop in response to a replicated paired-plot water stress experiment. We measured SIF using two platforms: a hydraulic lift and an Unmanned Aerial Vehicle (UAV) to capture temporal and spatial variation, respectively. LAD parameters were estimated from point clouds and photographic data and used to assess structural dynamics. Leaf phi F estimated from PAM fluorescence measurements were used to represent variations in photosynthetic regulation. We also measured foliar pigments, operating quantum yield of photosystem II (PSII), photosynthetic gas exchange, stomatal conductance and LAI. We used a radiative transfer model (SCOPE) to provide a means of decoupling structural and photosynthetic factors across the diurnal and spatial domains. The results demonstrate that diurnal variation in SIF is driven by photosynthetic and structural dynamics. The influence of phi F was prominent in the diurnal SIF response to water stress, with reduced fluorescence efficiencies in stressed plants. Structural factors dominated the spatial response of SIF to water stress over and above phi F. The results showed that the relationship between SIF and GPP is maintained in response to water stress where adjustments in NPQ and leaf angle co-operate to enhance the correlation between SIF and GPP. This study points to the complexity of interpreting and modelling the spatiotemporal connection between SIF and GPP which requires simultaneous knowledge of vegetation structural and photosynthetic dynamics.Peer reviewe

In vivo photoprotection mechanisms observed from leaf spectral absorbance changes showing VIS-NIR slow-induced conformational pigment bed changes

Regulated heat dissipation under excessive light comprises a complexity of mechanisms, whereby the supramolecular light-harvesting pigment-protein complex (LHC) shifts state from light harvesting towards heat dissipation, quenching the excess of photo-induced excitation energy in a non-photochemical way. Based on whole-leaf spectroscopy measuring upward and downward spectral radiance fluxes, we studied spectrally contiguous (hyperspectral) transient time series of absorbance A(λ,t) and passively induced chlorophyll fluorescence F(λ,t) dynamics of intact leaves in the visible and near-infrared wavelengths (VIS-NIR, 400-800 nm) after sudden strong natural-like illumination exposure. Besides light avoidance mechanism, we observed on absorbance signatures, calculated from simultaneous reflectance R(λ,t) and transmittance T(λ,t) measurements as A(λ,t) = 1 − R(λ,t) − T(λ,t), major dynamic events with specific onsets and kinetical behaviour. A consistent well-known fast carotenoid absorbance feature (500-570 nm) appears within the first seconds to minutes, seen from both the reflected (backscattered) and transmitted (forward scattered) radiance differences. Simultaneous fast Chl features are observed, either as an increased or decreased scattering behaviour during quick light adjustment consistent with re-organizations of the membrane. The carotenoid absorbance feature shows up simultaneously with a major F decrease and corresponds to the xanthophyll conversion, as quick response to the proton gradient build-up. After xanthophyll conversion (t = 3 min), a kinetically slower but major and smooth absorbance increase was occasionally observed from the transmitted radiance measurements as wide peaks in the green (~ 550 nm) and the near-infrared (~ 750 nm) wavelengths, involving no further F quenching. Surprisingly, in relation to the response to high light, this broad and consistent VIS-NIR feature indicates a slowly induced absorbance increase with a sigmoid kinetical behaviour. In analogy to sub-leaf-level observations, we suggest that this mechanism can be explained by a structure-induced low-energy-shifted energy redistribution involving both Car and Chl. These findings might pave the way towards a further non-invasive spectral investigation of antenna conformations and their relations with energy quenching at the intact leaf level, which is, in combination with F measurements, of a high importance for assessing plant photosynthesis in vivo and in addition from remote observations