Phenological Growth Stages Research Articles

Phenological Growth Stages According to the BBCH Scale Elaeagnus multiflora Thunb.

Phenology is a key trait of plants of all species, as it determines their season and duration of growth and reproduction, as well as their ability to capture variable resources. Understanding the phenology of Elaeagnus multiflora Thunb. a rare but promising fruit and medicinal plant of Ukraine, namely the codification of the stages of seasonal development, according to the international BBCH scale, is important for the evaluation of breeding material and the development of new varieties, improving the technological qualities of fruits. In the climatic conditions of Ukraine (M.M. Gryshko National Botanical Garden of the National Academy of Sciences of Ukraine, Kyiv), the studied genotypes of E. multiflora go through a full cycle of development. Plants begin the growing season with the development of leaves and shoots. According to the international BBCH scale, they clearly distinguish eight of the ten main stages of seasonal development, in particular: the development of buds (Principal growth stage 0), leaves (Principal growth stage 1), shoots (Principal growth stage 3), inflorescence emergence (Principal growth stage 5), flowering (Principal growth stage 6), fruit development (Principal growth stage 7), fruit ripening (Principal growth stage 8) and senescence and the onset of dormancy (Principal growth stage 9). The proposed BBCH scale for characterizing the phenological stages of E. multiflora plants can be used to guide the growers as to when to carry out orchard management practices such as canopy training and pruning, nutrient and water application, pest and disease control and post-harvest processing. Correct identification of phenological stages is of great importance for the characterization and management of E. multiflora. Thus, this study will ensure the dissemination of knowledge about E. multiflora cultivars among growers and researchers.

Effectiveness of snow harvesting and water productivity practices in combatting climate change‐induced drought in a Himalayan district of Nepal

Effectiveness of snow harvesting and water productivity practices in combatting climate change‐induced drought in a Himalayan district of Nepal

Phenological growth stages and growing degree days of peach [Prunus persica (L.) Batsch] in sub‐temperate climatic zone of North‐Western Himalayan region using BBCH scale

AbstractIn this study, the phenological stages of peach have been described for the first time according to the BBCH scale (Biologische Bundesanstalt, Bundessortenamt and Chemische Industrie) and Baggiolini codes for five cultivars (Pratap, Tropic Snow, Tropic Beauty, Redhaven and July Elberta) in sub‐temperate region of India, which markedly differentiates vegetative and reproductive stages occurring in peach. The growing degree days (GDD) are the best indicators for monitoring the different phenological growth stages and were determined from dormancy breaking to fruit harvest when the cultivars reached maturity. Pratap, Tropic Snow and Tropic Beauty were identified as early‐season maturing with 814 ± 5.10, 996 ± 8.13 and 1004 ± 8.72 GDD, respectively. While, Redhaven was mid‐season cultivar with 1502 ± 16.17 GDD, and July Elberta was the late‐season cultivar with 1894 ± 6.00 GDD. Mid‐season cultivar Redhaven performed better in India's sub‐temperate region, accounting for higher yield (54.87 kg per tree), fruit length: diameter (1.11), TSS (12.26%) and total sugars content (10.26%). The description presented in the paper will act as a tool to provide a consensual unified approach for standardisation of phenological stages in peach and also for various cultural inputs and timely planning of harvesting. Moreover, the BBCH scale will act as a tool to assess the impact of climate change on crop phenology and to evaluate the adaptation of particular peach cultivars to different conditions.

Phenological growth stage of tropical shallot (Allium cepa L. Aggregatum group) planted from seed in lowland area based on the BBCH scale

AbstractShallot (Allium cepa L. Aggregatum group) is an important Allium plant commonly grown in tropical countries, including Indonesia, and it is used as spice for daily cooking, medicine, cosmetics and dietary supplements. Since shallot is predominantly propagated vegetatively by bulbs, it augments pathogen accumulation which influences low seed bulb management as well as productivity. Hence, utilisation of seeds/True Seed Shallot (TSS) emerges an alternative propagation material. However, no information is available on the growth stages of shallot plants from TSS. The phenological growth stages of tropical shallot planted in lowland areas using seeds in accordance with the Biologische Bundesanstalt, Bundessortenamt nd CHemische Industrie (BBCH) scale are first described here. Five introduced TSS cultivars, that is, Tuk Tuk, Lokananta, Sanren, Maserati, Tropix and four landraces TSS cultivars, that is, Bima, Biru Lancor, Pancasona and Trisula, were used as planting materials to develop an extended numerical BBCH scale for the identification of different phenological growth stages of shallot from seed. The study was conducted in lowland areas under tropical conditions of Indonesia. Based on BBCH scale, phenology of tropical shallot from seed in lowland area exhibited five of the 10 principal stages (0–9): germination (stage 0), leaf development (stage 1), formation of lateral shoot/tiller of pseudostem (stage 2), development of bulb (harvestable vegetative part) (stage 4), and senescence (stage 9). The codification of the different growth stages is essential in determination of the correct timing for better crop management, particularly for transplanting, fertilisation, control of weeds, disease and pest, plant growth regulators application and harvest time. As an implication, these BBCH scales could be used in plant breeding activities to shorten the TSS life cycle.

Reproductive phenology of Vaccinium floribundum Kunth (Ericaceae) and codification according to the BBCH scale based on evidence from the volcano Chimborazo paramo (Ecuador)

• Deforestation, land conversion and natural resources overexploitation endanger “mortiño”. • Mortiño reproductive phenology not shows chronological orderly progression in monitored areas. • Different reproductive stages (bud, flower and fruit) were even observed within same individuals. • Extreme climatic conditions of paramo imposed physiological limitations on mortiño phenology. Vaccinium floribundum Kunth (Ericaceae) is a native Andean species with shrubby habit and edible fruits. It is mostly distributed in the paramos of the Andes, from Venezuela to Bolivia, where it is commonly known as "mortiño". In this study, we describe the reproductive phenological growth stages of V. floribundum in the paramo of the Chimborazo volcano in Ecuador, using an adaptation of the BBCH scale system, and according to semi-monthly observations conducted in three localities from January 2017 to June 2018 (18 months). In addition, a linear regression analysis was performed to detect any potential influence of climatic parameters on the reproductive phenology of “mortiño”. Throughout the monitoring period, different stages of reproductive growth such as bud, flower and fruit were simultaneously found among individuals and, sometimes, even in the same plant. The reproductive phenology of sampled individuals from sites 1 and 2 (Mindala Loma and Polylepis, respectively) were relatively synchronized, whereas individuals from site 3 (Mechahuasca) showed a different phenological pattern. A significant, apparently quick, loss of flowers was evident in all localities during the study period. The patterns observed could reflect physiological constraints imposed by the extreme weather conditions of the paramo.

A new phenology-based method for mapping wheat and barley using time-series of Sentinel-2 images

In recent years, various techniques have been developed to generate crop-type maps based on remote sensing data. Wheat and barley are two major cereal crops cultivated as the first and fourth largest grain crops across the globe. The variations in spectral temporal profile of both crops are generally insignificant at small scales and therefore the two crops are phenologically fairly clearly separated; however, at large scale areas the variance of phenological parameters increases for both crops due to the effects of various climatic and orographic factors which adversely influences discrimination of wheat and barley. Additionally, wheat and barley are usually cultivated as both spring and winter or early and late season crops in some areas, making it more difficult to distinguish them. Therefore, developing a new method based on remote sensing data for effective discrimination of wheat and barley is an important necessity in the field of precision agriculture. To this end, this research presents a new phenology-based method to discriminate barley from wheat. In this study, Sentinel-2 (S2) time-series data of a study site in Iran (Markazi) and two sites in the USA (Idaho and North California), are employed. Spectral reflectance values of wheat and barley are examined during the growing season and a new spectral-temporal feature is successfully developed for automatic identification of the barley heading date. The Relief-f algorithm is then employed to select appropriate spectral features of S2 to distinguish wheat from barley at the heading date. Finally, generated spectral features at the heading date are used as input to Support Vector Machine (SVM) and Random Forest (RF) to produce barley and wheat maps. The Kappa coefficient and overall accuracy (OA) obtained for the three study sites are more than 0.67 and 76%, respectively. The findings of this study demonstrate the potential of remote sensing data to identify the phenological growth stages of barley and distinguish it successfully from wheat.

Water uptake of soybean pods and seeds with different lignin contents

The identification of pod- and seed-related traits of soybean genotypes and their interaction with water uptake can be applied in breeding programs with a view to establishing cultivars developed for the production and maintenance of high-quality seeds. The objective was to evaluate the water uptake of pods and seeds of soybean cultivars with different lignin contents after different soaking periods. The experimental was arranged in a completely randomized, 7×10 factorial design, with four replications. The factors consisted of seven soybean cultivars and 10 soaking periods (1, 2, 3, 4, 5, 6, 7, 8, 24, 48 hours). The pods and seeds were grown in a greenhouse and harvested at the phenological growth stage R8 (at full maturation, when 95% of the pods had mature color). The following traits were evaluated: lignin content in pod and seed coat, moisture content, and rate of water uptake of pods and seeds. Soybean cultivars with pods with high lignin contents have a lower rate of water uptake. The lignin contents of the seed coats, within the chosen limits, did not affect the seed water uptake.

Effect of Rye cover crop on weed control, soybean (Glycine max L.) yield and profitability

Considerable variations in farm productivity were reported across soils and climates when winter cover crops (CC) were rotated with summer main cash crops. Hence, a three-year field study (2019-2021) was conducted on Dundee silt loam in a humid climate to assess soybean growth and yield, weed control, and profitability under no-till conditions in response to (i) no CC (NC), (ii) winter rye CC rolled when green, followed by soybean planting and desiccation by paraquat (GR) and iii) winter rye CC desiccated using paraquat and rolled followed by soybean planting (BR). No differences in phenological growth stages of soybean were observed among the treatments. Measured leaf area index was comparable among the treatments across the three seasons. The rate of rye CC biomass decay estimated eight weeks after planting (WAP) was much higher than at four WAP. In 2019, at eight WAP plant residue ranged from 29.3% under NC to 52.9% under GR, indicating the paraquat desiccated natural winter vegetation decays faster than the desiccated rye CC biomass. The weed biomass was 72% higher at eight WAP (0.29 Mg ha-1) than that of four WAP (0.17 Mg ha-1) and NC plots had higher weed biomass at both four WAP and eight WAP over CC plots. Field established soybean stand in the GR plots were consistently higher than the NC plots by 8%, 30%, and 22% in 2019, 2020, and 2021, respectively. Soybean yield in NC plot was 13% higher than GR and 15% higher than BR plots in 2019. However, in 2020 and 2021, soybean yield from BR and GR plots was significantly higher than NC plots (10% and 13%, respectively). In the three-year study, net returns from soybean with rye CC (regardless of GR or BR) in the first year was negative. In the second and third year, net returns in GR and BR were positive and comparable to NC. There were no differences in soybean yield and net returns between rye CC rolled green (GR) and rye CC desiccated (BR) prior to planting. These results show that a rye CC–based soybean conservation production system could be an economically a viable choice after the first year with an invaluable potential for carbon sequestration, weed suppression and positive impact on summer soybean productivity.

Crop Identification Based on Multi-Temporal Active and Passive Remote Sensing Images

Although vegetation index time series from optical images are widely used for crop mapping, it remains difficult to obtain sufficient time-series data because of satellite revisit time and weather in some areas. To address this situation, this paper considered Wen County, Henan Province, Central China as the research area and fused multi-source features such as backscatter coefficient, vegetation index, and time series based on Sentinel-1 and -2 data to identify crops. Through comparative experiments, this paper studied the feasibility of identifying crops with multi-temporal data and fused data. The results showed that the accuracy of multi-temporal Sentinel-2 data increased by 9.2% compared with single-temporal Sentinel-2 data, and the accuracy of multi-temporal fusion data improved by 17.1% and 2.9%, respectively, compared with multi-temporal Sentinel-1 and Sentinel-2 data. Multi-temporal data well-characterizes the phenological stages of crop growth, thereby improving the classification accuracy. The fusion of Sentinel-1 synthetic aperture radar data and Sentinel-2 optical data provide sufficient time-series data for crop identification. This research can provide a reference for crop recognition in precision agriculture.

Application of extended BBCH scale for studying the development of Phacelia tanacetifolia Benth.

AbstractPhacelia tanacetifolia is a fast‐growing crop from the family of Hydrophyllaceae that can be grown as an intercrop or also as a main crop, especially for the production of seed. It is grown both for fodder and for green manure and it is also an excellent melliferous plant. As it has no relation to other cultivated crops, it is suitable as a break crop in rotation. Despite its agrotechnological significance, no detailed study of its phenological development and detailed characterisation of growth stages have been published so far. The precise description of growth stages is a tool very useful not only for farmers but also for researchers. This paper presents a detailed characterisation of the development of P. tanacetifolia from germination to senescence. Based on research results, a characterisation of phenological growth stages is proposed using the extended BBCH scale. Individual methods of the evaluation of growth stages in plants are discussed and possibilities are assessed for using these methods in evaluating the development of P. tanacetifolia. The individual phenological growth stages of P. tanacetifolia are described using both the two‐ and three‐digit BBCH coding system. Schematic drawings illustrating the most representative growth stages are presented, too.

The Timing of Vegetative and Generative Development of 'Memecik' and 'Gemlik' Olive Cultivars

The research is carried out to determine the effects of different dates and temperatures on shoot length, fruit weight, oil content %, and maturity index of Gemlik and Memecik olive cultivars. The phenological growth stages of cultivars in ‘yield’ year were also described in the study using the BBCH (Biologische Bundesanstalt, Bundessortenamt, Chemische Industrie) scale. The shoot length observations were made on trees in the ‘on’ and ‘off’ periods between March 15, 2017, and December 29, 2017, every 15 days. It was determined that the shoot elongation of the trees in the ‘off’ period was even longer compared to the trees in the ‘on’ year. While the fruit weight of Gemlik had the highest value (3.775 g) on October 30, it had the highest value (3.330 g) on November 15 in Memecik. While fruit weight increased for 153 days for Gemlik, this period was determined as 122 days for Memecik. The maximum oil contents (%) were determined in Gemlik with 29.071 % on December 30 and in Memecik with 22.180 % on December 15. The maturity index of olive fruits reached its maximum level on December 15 in both varieties. As a result, it has been revealed that there is no serious difference between the phenological stages of the trees in the period of ‘on’ and ‘off’ depending on the periodic fruit yield. Moreover, the shoot development is generally more in the trees with ‘off’in terms of the course of shoot development, and when the pomological analysis regarding the productivity status are examined, there are some serious differences.

Phenological growth stages of shea tree (Vitellaria paradoxa subsp. paradoxa) according to the BBCH scale

AbstractThe shea tree is among the socio‐economically and environmentally most important plants in the Sudano‐Sahelian region of Africa. Shea butter is internationally valued for use in pharmaceutical, cosmetic and confectionary industries. Scaling and describing phenological growth stages is of great importance in crops management. However, such phenological scale is still lacking for shea tree. To fill this gap, we documented the different growth stages of shea tree by referencing to the Biologische Bundesantalt, Bundessortenamt und Chemische Industrie (BBCH) scale. Eight of the ten principal growth stages (0–9) and 43 secondary growth stages (0–9) were described in shea tree. Among the eight principal stages, four were related to reproductive phenophases: inflorescence emergence stage (5), flowering stage (6), fruit development stage (7), and fruit maturity stage (8). The remaining four principal stages concerned vegetative phenophases and contained: bud development stage (0), leaf development stage (1), shoot development stage (3), and senescence stage (9). Observations of shea tree phenophases depicted asynchronous growth patterns with overlapping secondary growth stages of different principal stages within an individual tree canopy at the same time. The proposed phenological growth scale specific to shea tree but compatible with other crops is a valuable contribution for the implementation of crops management protocols and the standardisation of research between different laboratories.

Phenological description and thermal time requirement of tamarind (Tamarindus indica) in tropical conditions

AbstractTamarind is one of the highly valued fruit trees of the tropical world. Considering the potential of the crop, a precise standardised description of its growth stages and thermal time requirement were studied to ensure efficient agronomic practices. Phenological growth stages of tamarind are defined according to the BBCH (Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie) scale using a three‐digit numerical system. The phenology of tamarind is characterised by eight principal growth stages: bud growth, leaf growth, shoot growth, inflorescence growth, flower development, fruit growth, fruit maturation and dormancy. Principal growth stages of tamarind are defined and described through 39 secondary growth stages. For each phenological stage, duration and thermal time were also ascertained. It is evident that thermal time for fruit growth and maturation of tamarind is substantially high, whereas inflorescence and leaf require less thermal time to complete their growth. The study could be of great help to tamarind growers and scientists for implementation of efficient agronomic management protocols as well as for assessing the response of critical phenological growth stages to temperature.

Bacillus velezensis strain B26 modulates the inflorescence and root architecture of Brachypodium distachyon via hormone homeostasis

Plant growth-promoting rhizobacteria (PGPR) influence plant health. However, the genotypic variations in host organisms affect their response to PGPR. To understand the genotypic effect, we screened four diverse B. distachyon genotypes at varying growth stages for their ability to be colonized by B. velezensis strain B26. We reasoned that B26 may have an impact on the phenological growth stages of B. distachyon genotypes. Phenotypic data suggested the role of B26 in increasing the number of awns and root weight in wild type genotypes and overexpressing transgenic lines. Thus, we characterized the expression patterns of flowering pathway genes in inoculated plants and found that strain B26 modulates the transcript abundance of flowering genes. An increased root volume of inoculated plants was estimated by CT-scanning which suggests the role of B26 in altering the root architecture. B26 also modulated plant hormone homeostasis. A differential response was observed in the transcript abundance of auxin and gibberellins biosynthesis genes in inoculated roots. Our results reveal that B. distachyon plant genotype is an essential determinant of whether a PGPR provides benefit or harm to the host and shed new insight into the involvement of B. velezensis in the expression of flowering genes.

Chemical Composition, Antioxidant and Antimicrobial Potential of the Essential Oils from Aerial Parts of Tagetes patula L. at Different Phenological Stages

The current study aims at determining the variability in composition, antibacterial and antioxidant properties of the essential oils extracted from aerial parts of Tagetes patula at different phenological stages of plant growth i.e., the vegetative, full blooming and seed setting stages. The maximum average yield of hydrodistilled essential oils was obtained as 0.083 ± 0.003% (seed setting), 0.068±0.007% (full flowering) and 0.059±0.005% (pre flowering). (Z)-β-ocimene was found to be most abundant compound of essential oil of T. patula, and α-terpinolene, piperitenone, limonene and propanedinitrile, dicyclohexyl were found as major compounds in oil extracted at different phenological stages of plant. Contribution of (Z)-β-Ocimene was highest in full flowering stage (18.27±3.14%) as compared to other two stages where its amount ranged from 12.03-17.17 %. α-Terpinolene the second major component was found highest in the pre-flowering stage (13.86±1.15%) compared to other stages. Significant variation was observed in the percent content of piperitenone during all three phenological stages The antioxidant (DPPH radical scavenging) assay showed that T. patula oils have maximum activity at the pre-flowering stage. Antibacterial activities of the essential oils were observed at the pre-flowering stage against different bacteria; i.e., Bacillus sp., Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, Staphylococcus aureus and exhibited promising values of MIC (0.125 % v/v -0.5 % v/v) and MBC (0.25 v/v to 1% v/v) against bacterial cultures.

Phenolic Composition and Antioxidant, Anti-Inflammatory, Cytotoxic, and Antimicrobial Activities of Cardoon Blades at Different Growth Stages.

Simple SummaryThe rapid increase of the world population has promoted a more sustainable and efficient use of natural resources. To achieve complete and proper upcycling of plant crops, it is important to know their potential for industrial exploitation. Cardoon (Cynara cardunculus L.) is a species native to the Mediterranean basin widely used in different sectors, including food and pharmaceuticals. Despite their multiple industrial applications, not all plant tissues have been incorporated into the value chain. Therefore, this work aimed to characterize the phenolic composition and bioactive properties of cardoon blades throughout the phenological growth cycle. In addition to the structural variety of phytochemicals detected in the blade extracts, their antioxidant, anti-inflammatory, anti-proliferative, and antimicrobial properties were also highlighted. While immature material showed higher levels of phenolic compounds and greater potential to inhibit lipid peroxidation, samples at higher development stages had greater anti-proliferative, anti-inflammatory, and antimicrobial potential. These results demonstrate that the growth cycle influences the bioactive potential of cardoon blades and will be useful to establish suitable industrial applications, such as the development of ingredients for functional foods and nutraceuticals, among other products.Cardoon (Cynara cardunculus var. altilis) blades were collected at sixteen sampling dates (B1–B16) to study the influence of the phenological growth stage on the phenolic composition and biological properties. Twenty phenolic compounds were identified, among which trans 3,4-O-dicaffeoylquinic acid, 5-O-caffeoylquinic acid, and luteolin-O-hexoside (39.6, 42.6, and 101.0 mg/g extract, respectively) were the main compounds. Immature blades (B3) had a higher content of phenolic compounds (178 mg/g extract) and a greater ability to inhibit the formation of thiobarbituric acid reactive substances (IC50 of 1.61 µg/mL). Samples at more advanced growth stages revealed a greater capacity to inhibit oxidative hemolysis (B8, IC50 of 25 and 47.4 µg/mL for Δt of 60 and 120 min, respectively) and higher cytotoxic (B8–B13, GI50 between 7.1 and 17 µg/mL), anti-inflammatory (B13, IC50 of 10 µg/mL), and antibacterial activities. In turn, the antifungal activity varied depending on the tested fungi. All these results suggest that maturity influences the phenolic composition and bioactive properties of cardoon blades, which reveal great potential for the development of bioactive ingredients for food and pharmaceutical applications, among others.

Phenological growth stages of Meconopsis aculeata Royle, an endangered medicinal plant of western Himalaya, using BBCH scale

Alpine plant species are perennial but have a shorter growing period according to prevailing habitat conditions that remain snow-covered during winter. In these areas, many of the species are important sources of valuable drugs. Phenological observations on Meconopsis aculeata were recorded at a weekly interval in Tungnath region of western Himalaya. Phenological studies in alpine plants are minimal, especially in Indian Himalayas thus, the present study was carried out to describe detailed phenological stages of M. aculeata in Tungnath region of the Indian Himalaya. The BBCH (Biologische Bundesantalt, Bundessortenamt, and Chemische Industrie) scale was used to characterize seven primary growth stages from seed germination to senescence, as well as secondary growth stages. These stages include stage 0 (germination phase), stage 1 (leaf development), stage 5 (Inflorescence emergence), stage 6 (flowering), stage 7 (fruit development), stage 8 (Fruit ripening) and stage 9 (Senescence). Due to the high market demand of medicinal plants in local and international markets, work on the various aspects of domestication and crop improvement is a dire need, therefore the detailed phenological growth stages of M. aculeata could be helpful and complimentary for local growers, breeders and researchers.

Winter Wheat Yield Estimation Based on Optimal Weighted Vegetation Index and BHT-ARIMA Model

This study aims to use remote sensing (RS) time-series data to explore the intrinsic relationship between crop growth and yield formation at different fertility stages and construct a high-precision winter wheat yield estimation model applicable to short time-series RS data. Sentinel-2 images were acquired in this study at six key phenological stages (rejuvenation stage, rising stage, jointing stage, heading stage, filling stage, filling-maturity stage) of winter wheat growth, and various vegetation indexes (VIs) at different fertility stages were calculated. Based on the characteristics of yield data continuity, the RReliefF algorithm was introduced to filter the optimal vegetation index combinations suitable for the yield estimation of winter wheat for all fertility stages. The Absolutely Objective Improved Analytic Hierarchy Process (AOIAHP) was innovatively proposed to determine the proportional contribution of crop growth to yield formation in six different phenological stages. The selected VIs consisting of MTCI(RE2), EVI, REP, MTCI(RE1), RECI(RE1), NDVI(RE1), NDVI(RE3), NDVI(RE2), NDVI, and MSAVI were then fused with the weights of different fertility periods to obtain time-series weighted data. For the characteristics of short time length and a small number of sequences of RS time-series data in yield estimation, this study applied the multiplexed delayed embedding transformation (MDT) technique to realize the data augmentation of the original short time series. Tucker decomposition was performed on the block Hankel tensor (BHT) obtained after MDT enhancement, and the core tensor was extracted while preserving the intrinsic connection of the time-series data. Finally, the resulting multidimensional core tensor was trained with the Autoregressive Integrated Moving Average (ARIMA) model to obtain the BHT-ARIMA model for wheat yield estimation. Compared to the performance of the BHT-ARIMA model with unweighted time-series data as input, the weighted time-series input significantly improves yield estimation accuracy. The coefficients of determination (R2) were improved from 0.325 to 0.583. The root mean square error (RMSE) decreased from 492.990 to 323.637 kg/ha, the mean absolute error (MAE) dropped from 350.625 to 255.954, and the mean absolute percentage error (MAPE) decreased from 4.332% to 3.186%. Besides, BHT-ARMA and BHT-CNN models were also used to compare with BHT-ARIMA. The results indicated that the BHT-ARIMA model still had the best yield prediction accuracy. The proposed method of this study will provide fast and accurate guidance for crop yield estimation and will be of great value for the processing and application of time-series RS data.

Seedling size and nutrient availability in the fall determine nitrogen resorption and storage compound allocation in Quercus variabilis

Soil fertility and resorption of leaf compounds in the fall can influence resource buildup in plants. However, whether intraspecific differences in seedling size can affect nutrient reserve buildup is unknown. This study examined the effects of seedling size and fall fertilization on the uptake and resorption of nitrogen (N), as well as the allocation of non-structural carbohydrates (NSC) and N in cultivated Quercus variabilis Blume. After the formation of terminal buds (T1), seedlings were stratified into small (shoot height < 30 cm) and large seedlings. During the hardening period, seedlings were treated with three different rates of 15 N-enriched fertilizer (0, 12, or 24 mg N seedling−1) and monitored until leaf fall (T2). Small seedlings had lower N resorption efficiency and resorbed proportionally less N than large seedlings. Fall fertilization notably improved N and NSC reserves, without reducing N resorption efficiency. Large seedlings allocated proportionally less N to leaves than small seedlings although both sizes seedlings absorbed similar amounts of N from fall fertilization. The priority perennial organ for NSC allocation was roots, while N allocation was dependent on the phenological growth stage of the seedling. Roots were prioritized during the rapid growth phase, while stems were prioritized during the hardening period. Under same fertilizer regime during the growth phase, large seedlings tends to have lower N concentration and have higher resorption efficiency compare to small seedlings, fall fertilization can increase N storage in large seedlings and NSC levels in both seedling sizes, without affecting growth.

Effects of organic and inorganic fertilization on growth and yield of Physalis peruviana L. crop under Mediterranean conditions

Physalis peruviana L. is an Andean Solanaceae fruit crop with great nutraceutical qualities, potential health benefits and adaptability to Mediterranean climates. In the current study, a first approach on the effect of organic and inorganic fertilization on P. peruviana crop under Mediterranean semi-arid conditions was performed. A field experiment was laid out according to a completely randomized design, with three replicates and three fertilization treatments [untreated (control), organic fertilization (biocyclic humus soil) and inorganic fertilization (inorganic fertilizer 40-0-0+14.5 SO3)]. Phenological growth stages and their corresponded growing degree days were evaluated. In addition, some growth parameters, fruit yield and yield components were evaluated. The results indicated that the duration of phenological growth stages was in accordance with durations mentioned in tropical climate. The highest branches number per plant (24.4), leaf area per plant (1997.3 cm2), fruit number per plant (41.52), fruit yield (7.51 t ha-1) and average fruit weight (5.32 g) were found in inorganic fertilization plots, whereas the highest plant height (44.15 g) and fruit diameter (12.52 mm) were recorded under organic fertilization; however, the differences between the organic and inorganic fertilization were not statistically significant. In terms of dry weight per plant, there were significant differences among the fertilization treatment with the values obtained under inorganic fertilization (81.24 g). To sum up, P. peruviana showed satisfying adaptability under Mediterranean climate conditions and has great potential in becoming an alternative cultivation for small and medium producers of Mediterranean countries. In addition, the results indicated that organic fertilization (with biocyclic humus soil) should be considered as an alternative to inorganic fertilizers for P. peruviana production.