Tryptophan metabolism and bacterial commensals prevent fungal dysbiosis in Arabidopsis roots

In nature, roots of healthy plants are colonized by multikingdom microbial communities that include bacteria, fungi, and oomycetes. A key question is how plants control the assembly of these diverse microbes in roots to maintain host–microbe homeostasis and health. Using microbiota reconstitution experiments with a set of immunocompromised Arabidopsis thaliana mutants and a multikingdom synthetic microbial community (SynCom) representative of the natural A. thaliana root microbiota, we observed that microbiota-mediated plant growth promotion was abolished in most of the tested immunocompromised mutants. Notably, more than 40% of between-genotype variation in these microbiota-induced growth differences was explained by fungal but not bacterial or oomycete load in roots. Extensive fungal overgrowth in roots and altered plant growth was evident at both vegetative and reproductive stages for a mutant impaired in the production of tryptophan-derived, specialized metabolites (cyp79b2/b3). Microbiota manipulation experiments with single- and multikingdom microbial SynComs further demonstrated that 1) the presence of fungi in the multikingdom SynCom was the direct cause of the dysbiotic phenotype in the cyp79b2/b3 mutant and 2) bacterial commensals and host tryptophan metabolism are both necessary to control fungal load, thereby promoting A. thaliana growth and survival. Our results indicate that protective activities of bacterial root commensals are as critical as the host tryptophan metabolic pathway in preventing fungal dysbiosis in the A. thaliana root endosphere.

Model-Based Growth Comparisons between Loblolly and Slash Pine and between Silvicultural Intensities in East Texas

Growth differences between key commercial species and between silvicultural intensities (phases) within a species in a region are of great interest to foresters. This study used modeling methods to investigate these differences in east Texas. Datasets collected from loblolly and slash pine plots installed in extensively managed plantations (Phase I) and loblolly pine plots installed in intensively managed plantations (Phase II) were used. Species and silvicultural phase growth differences were determined by comparing their height–age, diameter–age, and height–diameter relationships. Slash and loblolly pine had significantly different parameter estimates for the Chapman and Richards function-based height– and diameter–age models. Slash pine grew faster than loblolly pine, with the superiority in height increasing while that of diameter growth decreased slightly with age. Slash and loblolly pine differed also in all parameter estimates of the exponential function-based height-diameter model. Loblolly pine was taller than the slash for small size (DBH ≤ 18 cm) trees, but thereafter, slash pine outperformed loblolly. While these results may encourage planting slash pine in the region, more studies are needed before definitive conclusions can be made. The differences in the height–age models for loblolly pine Phase I and II plots suggest that intensive management significantly enhanced tree height growth. However, this enhancement did not substantially change the maximum height; instead, trees reached the maximum height younger, thus effectively shortening the rotation age.

Root Growth Dynamics and Structure in Seedlings of Four Shade Tolerant Mediterranean Species Grown under Moderate and Low Light

Specific functional traits such as shade tolerance or leaf habits can enhance root growth dynamics and structure of planted seedlings in the understory of planted forests. We assessed how low and moderate light levels (17 and 33% of full sunlight, mimicking after-thinning stocking) affect the root growth dynamics and structure of four late successional trees, three deciduous (Acer monspessulanum L., Quercus pyrenaica Willd and Sorbus torminalis (L.) Crantz) and one evergreen (Quercus ilex L.) species. Rooting depth, dynamics and structure were mainly explained by species functional differences. Roots of deciduous trees elongated faster and deeper and were larger than the roots of the evergreen Q. ilex. Among deciduous trees, S. torminalis had the lowest root growth. Specific leaf area and nutrient concentration were positively related to root growth, highlighting the importance of traits related to the plant economic spectrum, as determinants of species root growth differences. Moderate light level slightly enhanced root growth and decreased the specific leaf area (SLA). Species differences in water potential under drought were positively related to rooting depth, evidencing the importance of its role in overcoming drought stress during seedling establishment. These findings can guide the selection of late successional, shade tolerant tree species for underplanting thinned Mediterranean plantations and provide insights into their ecology.

The effect of probiotic and prebiotic-MOS on the survival, growth and immune competence on spiny lobster Panulirus homarus culture

The use of probiotics and prebiotic to improve growth and health status of spiny lobster has been evaluated. The purpose of this study was to obtain the effect of probiotics and prebiotics for the culture of spiny lobster Panulirus homarus. The method was initiated with culturing of probiotics (4 strains) and supplemented it in a moist diets. Spiny lobster was collected from Jembrana-Bali waters with an initial body weight of 70.34 ± 4.5 g and cultured in concrete tanks with volume of 4 m3. Initial stock density for each treatment was 15 pcs / m3. The treatments tested were supplemented on moist diets with (A) probiotics, (B) probiotics and prebiotics-MOS (Mannan Oligo Sacharida) and (C) Controle (without probiotics and prebiotic) and each treatment with three replication. The results obtained that the survival rate of spiny lobster was not significantly different (P> 0.05), i.e. (A) 92.70%, (B) 93.33 (%) and (C) 93.33% respectively. However, the results of probiotics supplementation as well as a combination of probiotics and prebiotics showed growth differences compared to control (P<0.05), namely (A) 156.97 ± 6.17 g, (B) 153.75 ± 9.17 g, while (C) control 131.47 ± 7.91 g. The probiotics supplementation on moist diets could increased health status of spiny lobsters, this was expressed by target genes related to immunity (ALFHa-1, ALFHa-4, SAA, ProPO, Tgase and CP). Spiny lobster immunity increased by 2.60 to 42.7 times after challenging with MHD (Milky Haemolymph Disease). The supplementation of probiotics and prebiotics (MOS) could increase immune response by 2.10 to 25.75 times, respectively after challenging with MHD.

Analysis of Weather-Related Growth Differences in Winter Wheat in a Three-Year Field Trial in North-East Germany

Winter wheat is the most important crop in Germany, which is why a three-year field trial (2015–17) investigated the effects of weather on biometric parameters in relation to the phenological growth stage of the winter wheat varieties Opal, Kerubino, Edgar. In Brandenburg, there have been frequent extreme weather events in the growth phases that are relevant to grain yields. Two winter wheat varieties were grown per trial year and parts of the experimental field areas were irrigated. In addition, soil physical, biometric and meteorological data were collected during the growing season (March until end of July). There were five dry periods in 2015, six in 2016, and two in 2017 associated with low soil moisture. Notably, in 2016 the plant height was 5 cm lower and the cover was 15% lower than on irrigated plots. The grain yield was increased by 19% and 31% respectively by irrigation. However, due to irrigation costs, the net grain yield on irrigated plots was lower than on the unirrigated plots. It turned out that in dry years there were hardly any differences between winter wheat varieties. Multiple regression analysis showed a strong correlation between the biometric parameters considered here and the grain yield.

Sentinel-2 Imagery Monitoring Vine Growth Related to Topography in a Protected Designation of Origin Region

Remote sensing satellite platforms provide accurate temporal and spatial information useful in viticulture with an increasing interest in their use. This study aims to identify the possibilities of freely available and with frequent revisit time Sentinel-2 satellites, to monitor vine growth at regional scale on a vine-growing Protected Designation of Origin (PDO) zone during the growing season of the year 2019. This study aims to: (i) investigate through several Vegetation Indices (VIs) the vine growth differences across the zone and relations with topographic parameters; (ii) identify VIs that best recognize differences on subzones of different climatic conditions; (iii) explore the effectiveness of the Sentinel-2 data monitoring management applications. A total of 27 vineyards were selected for field and satellite data collection. Several VIs have been calculated per vineyard from a 20-date time series dataset. VIs showed high negative correlation with topographic parameter of elevation on the flowering stage. The analysis of variance between the VIs of the subzones showed that these regions have statistically significant differences, that most VIs can expose on the flowering and harvest stage, and only Normalized Difference Vegetation Index (NDVI) and VIs using Red-Edge bands during the veraison period. Sentinel-2 data show great effectiveness on monitoring management applications (tillage and trimming).

Field Performance of False Horn Plantain (Musa AAB) Corms Treated Mechanically and with Hormone Solutions

The growth and yield performance of macropropagated plantlets of the False Horn plantain cultivar ‘Apantu’ was evaluated due to the lack of reliable data on the effectiveness of that planting material under typical farming conditions in West Africa, Ghana. Corms were either mechanically treated by the Plants Issus de Fragments de tige (PIF) technique to destroy the apical meristem or remained intact as untreated controls. Subsequently, PIF-treated corms were vacuum infiltrated with either natural or synthetic plant hormone solutions. Emerging plantlets were harvested, acclimatized for three months and planted in a freshly prepared field. Vegetative growth characteristics of each mother (main) plant were taken at 6 and 9 months after planting and for the main and first sucker crop along with yield parameters at harvest, respectively. The results indicated that treatment induced growth differences at 6 and 9 months after planting and were no longer significant at harvest. Consequently, final growth performance was quite homogenous across all treatments for the main and sucker crop, respectively. In contrast, fruit yield parameters of the main and sucker crops were to some extent affected by treatment; however, hormone infiltration tended to have little additional effect over the PIF-treatment. Nevertheless, treating corms with hormonal solutions enhanced the production of rooted plantlets at the nursery stage and ensured improved field performance.

Let’s Talk about Placental Sex, Baby: Understanding Mechanisms That Drive Female- and Male-Specific Fetal Growth and Developmental Outcomes

It is well understood that sex differences exist between females and males even before they are born. These sex-dependent differences may contribute to altered growth and developmental outcomes for the fetus. Based on our initial observations in the human placenta, we hypothesised that the male prioritises growth pathways in order to maximise growth through to adulthood, thereby ensuring the greatest chance of reproductive success. However, this male-specific “evolutionary advantage” likely contributes to males being less adaptable to shifts in the in-utero environment, which then places them at a greater risk for intrauterine morbidities or mortality. Comparatively, females are more adaptable to changes in the in-utero environment at the cost of growth, which may reduce their risk of poor perinatal outcomes. The mechanisms that drive these sex-specific adaptations to a change in the in-utero environment remain unclear, but an increasing body of evidence within the field of developmental biology would suggest that alterations to placental function, as well as the feto-placental hormonal milieu, is an important contributing factor. Herein, we have addressed the current knowledge regarding sex-specific intrauterine growth differences and have examined how certain pregnancy complications may alter these female- and male-specific adaptations.