Plant responses to mechanical stimulation have a great potential for growth control of ornamentals plants and vegetable seedlings and is a major requirement to ensure plant compactness and stability. 21 days old tomato (Solanum lycopersicum cv. 'Romello') plants were exposed to regularly applied mechanical stimuli for 14 days by applying of a defined air stream through a custom-built air stream applicator. Air stream application gradually reduced total plant leaf area by 14% and promoted radial growth relative to internode length compared to the untreated control, resulting in a more compact and stable plant phenotype, which was also related to an increased stem dry matter content of the air stream-treated plants. The reduction in total plant leaf area was compensated for the translocation of proportionally more assimilates to light-harvesting tissues and to stems at the expense of dry mass accumulation in petioles. Total stem, leaf and root dry mass of air stream-treated plants were unaffected. The specific leaf area of the air stream treated plants was reduced compared to the control, resulting in an increased relative leaf greenness and consequently in an 8% higher net carbon assimilation rates on average compared to the control. Thereby, air stream-treated plants were able to maintain overall biomass accumulation at the same level as the control. Leaf transpiration rate of air stream treated plants was not markedly affected in the long-term. The technique presented should be easily transferable to other plants, such as ornamentals where the application of chemical plant growth regulators is still the most common technique for plant growth control.

Stem elongation control is a fundamental requirement for the production of high-quality seedlings in terms of plant compactness and stability. It is known that stem elongation of seedlings can be inhibited by mechanical stimulation. In this study, a custom-built air stream applicator was used to apply intermittent stimuli to tomato (Solanum lycopersicum cv. 'Romello'). Tomato plants were cultivated under greenhouse conditions for 21 days and then exposed to intermittent air stimuli at different air stream application frequencies (8, 24, 40, 56, 72 and 80 d−1) and different air stream velocities (0.7 – 6.0 m s−1) for 14 days. Tomato plants responded with an inhibition of stem elongation of approximately 31% compared to the untreated control, without a systematic dose-response relationship related to application frequency. In contrast, stem elongation inhibition was significantly affected by air velocity, with a sigmoid dose-response relationship with negligible effects up to 2.0 m s−1, followed by a steep increase in the reduction effect up to 4.7 m s−1 and a fading of the effect at 36 % reduction for air velocities beyond that. Dry mass of leaves, stems, and petioles was reduced by approximately 10%, 41%, and 19%, respectively, after 14 days of treatment at a gradually increasing air velocity from 3.5 m s−1 at day 0 to 6.1 m s−1 at day 14 and an application frequency of 8 d−1. Root dry mass was less affected by the air stream application, but showed a slight tendency to decrease compared to control plants.

Abstract Apple (Malus × domestica Borkh.) cropping behavior, if not regulated, is often manifested by high yields of small-sized fruit in so called ON-years, which are usually followed by strongly reduced crop loads in OFF-years. Such cropping pattern is defined as biennial bearing and causes significant losses in apple production. The growth of apple fruit overlaps with the formation of flower buds, which remain dormant until the following spring. Earlier works proposed that some fruit-derived mobile compounds, as e.g., phytohormones, could suppress flower bud formation that thereby leads to biennial bearing. We addressed this hypothesis by analyzing 39 phytohormones in apple seeds, fruit flesh and by measuring phytohormone export from the fruits of the biennial bearing cultivar ‘Fuji’ and of the regular bearing cultivar ‘Gala’. Moreover, we analyzed the same compounds in bourse buds from fruiting (ON-trees) and non-fruiting (OFF-trees) spurs of both apple cultivars over the period of flower bud formation. Our results showed that apple fruit exported at least 14 phytohormones including indole-3-acetic acid and gibberellin A3; however, their influence on flower bud formation was inconclusive. A gibberellin-like compound, which was detected exclusively in bourse buds, was significantly more abundant in bourse buds from ON-trees compared with OFF-trees. Cultivar differences were marked by the accumulation of trans-zeatin-O-glucoside in bourse buds of ‘Gala’ ON-trees, whereas the levels of this compound in ‘Gala’ OFF were significantly lower and comparable to those in ‘Fuji’ ON- and OFF-trees. Particular phytohormones including five cytokinin forms as well as abscisic acid and its degradation products had higher levels in bourse buds from OFF-trees compared with ON-trees and were therefore proposed as potential promotors of flower bud initiation. The work discusses regulatory roles of phytohormones in flower bud formation in apple based on the novel and to date most comprehensive phytohormone profiles of apple fruit and buds.

This study documents the impact of a gender-sensitive home garden project initiated to mitigate the food and nutritional insecurity of 114 households in seven Mbororo communities in Cameroon’s Northwest region. Key lessons learned regarding the empowerment of the Mbororo women; socio-economic and nutritional health benefits derived by Mbororo households from the cultivation of nutrient-rich, high market-value, and indigenous vegetables; and challenges faced during the project lifecycle are outlined. It is envisaged these lessons will support public, private, and civil society actors initiating similar home garden projects to address the food and nutrition insecurity of other minority groups in Sub-Saharan Africa.

The cropping behavior of biennial apple (Malus ×domestica Borkh.) cultivars is irregular and often follows a biennial bearing pattern with 'On' years (high crop load and inhibited floral bud formation) followed by 'Off' years (little crop load and a promoted formation of floral buds). To study proteomic differences between floral and vegetative buds, trees of the strongly alternating cultivar 'Fuji' and the regular bearing cultivar 'Gala' were either completely thinned or not thinned at full bloom to establish two cropping treatments with no ('Off') or a high ('On') crop load, respectively. Student's t-Tests indicated significant differences of protein profiles in buds from 2-year old spurs from both treatments at each sampling date. Abundance patterns of protein clusters coincided with the onset of floral bud initiation and were most noticeable in buds from 'On' trees with a decreased abundance of key enzymes of the phenylpropanoid and flavonoid pathways and an increased abundance of histone deacetylase and ferritins. Furthermore, an increased abundance of proteins involved in histone and DNA methylation was found in the buds from 'Off' trees. This study presents the first large-scale, label-free proteomic profiling of floral and vegetative apple buds during the period of floral bud initiation. SIGNIFICANCE: Although several studies exist that address the complex developmental processes associated with the formation of floral buds in apple (Malus ×domestica Borkh.) at transcriptomic level, no data is available for explaining the difference between floral and vegetative buds or biennial and regular bearing cultivars on a proteomic level. This study presents the first large-scale, label-free proteomic profiling of floral and vegetative apple buds from the two cultivars 'Fuji' and 'Royal Gala' during the period of floral bud initiation and renders possible the development of suitable biomarkers for biennial bearing in apple.

Apples are very susceptible to infections from various fungal pathogens during the growing season due to prolonged exposure to environmental influences in the field. Therefore, a strict and targeted fungicide strategy is essential to protect fruit and trees. Increased environmental and health concerns and pathogen resistance have resulted in a rising demand to reduce fungicide usage and residues on marketed fruit. Thus, producers must develop new plant protection strategies to conform to the legal and social demands while still offering high-quality apples. This study assessed the efficacy of a post-harvest fungicide treatment with pyrimethanil via thermo-nebulization for controlling storage rots and compared the results to those of standard pre-harvest fungicide strategies. The results showed that a single post-harvest application of pyrimethanil successfully controlled storage rots and is comparable to strategies using multiple pre-harvest fungicide applications. The control of fungal rot was sustained even after 5 months of storage and 2 weeks of shelf life. Thermo-nebulization into the storage facility allowed for a lower dosage of fungicide to be used compared to pre-harvest applications, while still maintaining optimal rot control. Residue analyses showed that the post-harvest fungicide treatment did not exceed legal or retailer's standards.

ISHS I International Symposium on Reproductive Biology of Fruit Tree Species What else don’t we know about biennial bearing? Phytohormone profile of seeds and seed number per fruit differ between a biennial and a non-biennial apple cultivar

This study investigated the dynamic changes in the anaerobic metabolism end products (ethanol, acetaldehyde and ethyl acetate) of different apple cultivars during 84-days of regular air (RA) and controlled atmosphere (CA) storage after 0-, 3-, 7- and 14-days of anoxia. Increasing the length of exposure to anoxia increased the anaerobic metabolites concentrations (AMC) in all cultivars. Fruit could recover from anoxia, and the AMC dissipated after 84-days of storage under both storage systems when the duration of anoxia was <7-days. The rate of metabolite dissipation following 14-days of anoxia differed among cultivars and storage systems. The reduction in AMC was faster under CA than RA-storage for 'Golden Delicious' and 'Jonagold' fruit, while the opposite trend was observed for 'Kanzi'. These results indicate that storage under CA post anoxia maintains better fruit quality during 84-days of storage than RA and effectively reduces the AMC.

Background Cherries are stone fruits and belong to the economically important plant family of Rosaceae with worldwide cultivation of different species. The ground cherry, Prunus fruticosa Pall. is one ancestor of cultivated sour cherry, an important tetraploid cherry species. Here, we present a long read chromosome-level draft genome assembly and related plastid sequences using the Oxford Nanopore Technology PromethION platform and R10.3 pore type. Finding The final assemblies obtained from 117.3 Gb cleaned reads representing 97x coverage of expected 1.2 Gb tetraploid (2n=4x=32) and 0.3 Gb haploid (1n=8) genome sequence of P. fruticosa were calculated. The N50 contig length ranged between 0.3 and 0.5 Mb with the longest contig being ∼6 Mb. BUSCO estimated a completeness between 98.7 % for the 4n and 96.1 % for the 1n datasets. Using a homology and reference based scaffolding method, we generated a final consensus genome sequence of 366 Mb comprising eight chromosomes. The N50 scaffold was ∼44 Mb with the longest chromosome being 66.5 Mb. The repeat content was estimated to ∼190 Mb (52 %) and 58,880 protein-coding genes were annotated. The chloroplast and mitochondrial genomes were 158,217 bp and 383,281 bp long, which is in accordance with previously published plastid sequences. Conclusion This is the first report of the genome of ground cherry ( P. fruticosa ) sequenced by long read technology only. The datasets obtained from this study provide a foundation for future breeding, molecular and evolutionary analysis in Prunus studies.

ISHS V International Humulus Symposium Genetic variations within the promoters of the genes for bitter acid and flavonoid biosynthesis of hop partly explain different levels of bitter acids between cultivars

Each year 25-75% of banana and plantain yields are lost because of rhizome damages caused by banana weevil (Cosmopolites sordidus) in growing regions of sub-Saharan Africa. However, the specific plant defence response of the rhizome tissue in relation to theC. sordidusattack is unknown. Consequently, in this study, we evaluated whether plant defence substances in the rhizome are correlated with the degree of larval damage and whether applications of methyl jasmonate (MJ) elicit a greater induction of the plant defence potential againstC. sordidus. Moreover, we attempted to reveal cellular modifications in response to the root feeding herbivore through histochemical staining. The banana cultivars "Km5" and "Mbwazirume" with tolerance and susceptibility toC. sordidus, respectively, were used in a pot experiment to evaluate percent rhizome damage, leaf chlorophyll content, total phenolic content (TPC), antioxidant capacity and cell morphology in response toC. sordidusattack and/or MJ applications compared to untreated control plants. We found thatC. sordidus-induced rhizome damage was 30% in the susceptible cultivar but less than 5% in the tolerant cultivar. The percent rhizome damage was not related to leaf chlorophyll content but showed a significant negative linear relationship to both TPC and antioxidant capacity. Larvae feeding induced a considerably greater increase of polyphenolic defence compounds in Km5 than in Mbwazirume; however, this response was opposite in the MJ treatment, suggesting that the phytohormone induced the susceptible plant to invest more into the synthesis of defence chemicals that in turn lead to reducedC. sordidusdamage. Tissue staining demonstrated a greater deposition of lignin and suberin inC. sordiduschallenged rhizome, presumably to seal off healthy tissue with a physical barrier from continued pest attack. It is concluded that MJ induces polyphenolics in susceptible Mbwazirume banana that reducedC. sordidusdamage.

The present study aimed to evaluate the effect of two ethanol vapor doses (250 and 500 ppm), 1-methylcyclopropene (1-MCP) (0.650 ppm) with or without ethylene application (150 ppm) on the aerobic and anaerobic metabolism and quality of 'Elstar', a fast ripening apple cultivar, and 'Nicoter', a slowly ripening apple cultivar, over 14 d of holding at room temperature (20 +/- 2 degrees C). Fruit were subjected to treatments for 24 h and analyses performed after 0, 7 and 14 d holding at room temperature (20 +/- 2 degrees C). For both cultivars studied, ethanol vapor treatments, especially 500 ppm, inhibited the ripening of apples even when combined with 150 ppm of ethylene, but not as much as 1-MCP treatment in 'Nicoter' apples. Fruit treated with ethanol vapor maintained lower electrolyte leakage, higher flesh firmness, greener color and had more healthy fruit. However, its application increased the pyruvate decarboxylase (PDC) and alcohol dehydrogenase (ADH) activity, acetaldehyde and ethyl acetate accumulation, but in concentrations below the odor threshold reported in the literature. The 1-MCP treatment increased decay incidence, reducing the healthy fruit amount in 'Nicoter' apples after 14 d, but maintained a very low ethylene production and respiration rate, which allowed higher acidity maintenance after 14 d holding at room temperature. There was no incidence of external and internal physiological disorders in both cultivars.

Purpose Limited data are available in facilitating nutritional interventions in developing countries. The objective of this study is to assess the mean dietary diversity score (DDS)of Mbororo minority women in the Northwest region of Cameroon. Design/methodology/approach The study used the random sampling technique within the Mbororo minority communities (Adorates). A questionnaire on dietary diversity, including 461 Mbororo women, provided information on food consumed using the 24-h dietary recall method. Findings Various socio-cultural and economic characteristics of the Mbororo women affected the nutrient level of their diet. Moreover, starchy staples, vitamin-A rich vegetables and palm oil and milk and milk products were consumed by more than half of the Mbororo community. Family herd size showed a positive influence on the dietary habit of the Mbororo population. The mean DDS significantly increased (p = 0.001), as herd size increased from below 50 (3.9 ± 1.1) to above 100 (4.8 ± 1.2). Practical implications Most of the diet consumed by the Mbororo women were low in iron, making them susceptible to nutrition anemia. The diet of the Aku women was more deficient in micronutrients than their Jaafun counterpart. These results indicate suitable areas of intervention for any nutrition program that targets the Mbororo minority group of Northwest Cameron. Social implications DDS can be used in assessing and classifying the population in rural communities according to the deficiencies in micronutrients of their diet. Originality/value The use of DDS to assess the nutrient quality of diets is frequently used to evaluate the prevalence of micronutrient deficiencies but has never been applied to Mbororo minority women.

The induction of flower buds in apple ( Malus × domestica Borkh.) is tightly connected to biennial bearing, which is characterized by alternating years with high (ON) and low or no (OFF) crop loads. In order to study this irregular cropping behavior, spur buds from ON- and OFF-trees of the biennial-bearing cultivar ‘Fuji’ and the regular bearing cultivar ‘Gala’ were collected. First, the time of flower bud initiation was precisely determined for both cultivars by histological analysis. Moreover, for a systematic understanding of flower bud induction in apple, the physiological and molecular mechanisms within the bud tissue were evaluated over four weeks prior to flower bud initiation by employing a multi-omics approach, including RNA sequencing, proteomic and metabolic profiling. Gene and protein enrichment analysis detected physiological pathways promoting and inhibiting early flower bud development. Metabolic profiles from the cropping treatments revealed a greater abundance of thiamine, chlorogenic acid, and an adenine derivative in spur buds from OFF-trees, whereas tryptophan was more abundant in the buds collected from ON-trees. Cultivar comparison indicated that chlorogenic acid was more abundant in ‘Gala’ than in ‘Fuji’ spur buds, whereas the opposite effect was found for tryptophan. Genes controlling tryptophan biosynthesis were not affected by ON- and OFF-treatments, but genes assigned to the metabolism of tryptophan into indoleacetate were differentially expressed between cultivars and treatments. The multi-omics approach permitted analyzing complex plant metabolic processes involved in early flower bud development and more specifically presumably in flower bud induction by tracing some pathways from gene to product level.