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The efficient use of phosphate fertilizers and optimization of the amounts of irrigation water can maximize tomato growth and fruit production. This study aimed to evaluate the effects of different phosphorus (P) doses and sources on the growth and production components of tomato plants of the cultivar Gaúcho Melhorado Nova Seleção subjected to different irrigation water percentages. To achieve this, we set up an experiment using a factorial design to test the effects of four doses of P2O5 (corresponding to 25%, 50%, 100%, and 200% of the recommended dose), two P sources (monoammonium phosphate—MAP and organomineral—OM), and four irrigation water percentages (50%, 75%, 100%, and 125% of field capacity). Tomato plant growth improved when water was supplied at a percentage close to 100% of field capacity, with increased plant height, leaf length, and number of flowers observed (increases of 11.95%, 7.33%, and 13.87%, respectively, compared to 50% of field capacity). However, both excess and deficit irrigation resulted in morphological changes in tomato plants. Additionally, we observed that OM was more effective than MAP in increasing plant diameter and number of flowers, with increases of up to 36.4% and 227.6%, respectively, when using OM. Conversely, tomato growth was negatively affected by higher doses of MAP doses, suggesting that 25% of the recommended dose may yield the best growth rates. We verified that tomato plants can compensate for low phosphorus doses by increasing productivity with higher water amounts (125%–42.40 t ha−1), but high phosphorus doses result in greater fruit production with lower water percentages (50%–41.52 t ha−1). [ABSTRACT FROM AUTHOR]

Aim: The response of South American seasonally dry tropical forest (SDTF) and savanna species to the Quaternary climate changes is still poorly understood. Here we use multi‐model inference approach to compare the phylogeography and demographic history of five trumpet tree species (also known as pau‐d'arco) and draw general biogeographical patterns: Handroanthus impetiginosus, H. ochraceus, H. serratifolius, Tabebuia aurea and T. roseoalba. Location: Amazonia, Atlantic Forest, Cerrado and Caatinga ecoregions, South America and Brazil. Taxa: Bignoniaceae, Tabebuia Alliance, trees. Methods: We compiled genetic data, occurrence records and ecological niche modelling (ENM) from published articles. We used coalescent modelling to test patterns of co‐divergence, and analysed niche breadth and overlap and spatial patterns in genetic diversity using quantile regressions. Results: Species showed concordant lineage divergence times in the Pleistocene. Lineage diversification and phylogeographical patterns are more related to species niche breadth than to biome (savanna or SDTF). Differences in genetic diversity among species matches the expected for the demographic scenarios obtained with coalescent simulations and ENMs: species with wider range expansion during the Last Glacial Maximum had higher diversity than species with range retraction or multiple refugia. Main Conclusions: Diversification burst in the Pliocene, and major diversification of lineages during the Pleistocene seems to be a general pattern in SDTF and savannas in the South America. The high number of haplotypes at the Central Brazil, corresponding to the Cerrado ecoregion, highlights the importance of Protected Areas for SDTFs and savannas, highly threatened biomes in Brazil. [ABSTRACT FROM AUTHOR]

Biotic stress in cotton plants caused by the phytopathogenic fungus Colletotrichum gossypii var. cephalosporioides triggers symptoms of ramulosis, a disease characterized by necrotic spots on young leaves, followed by death of the affected branch's apical meristem, plant growth paralysis, and stimulation of lateral bud production. Severe cases of ramulosis can cause up to 85% yield losses in cotton plantations. Currently, this disease is controlled exclusively by using fungicides. However, few studies have focused on biological alternatives for mitigating the effects of contamination by C. gossypii var. cephalosporioides on cotton plants. Thus, the hypothesis raised is that endophytic fungi isolated from an Arecaceae species (Butia purpurascens), endemic to the Cerrado biome, have the potential to reduce physiological damage caused by ramulosis, decreasing its severity in these plants. This hypothesis was tested using plants grown from seeds contaminated with the pathogen and inoculated with strains of Gibberella moniliformis (BP10EF), Hamigera insecticola (BP33EF), Codinaeopsis sp. (BP328EF), G. moniliformis (BP335EF), and Aspergillus sp. (BP340EF). C. gossypii var. cephalosporioides is a leaf pathogen; thus, the evaluations were focused on leaf parameters: gas exchange, chlorophyll a fluorescence, and oxidative metabolism. The hypothesis that inoculation with endophytic strains can mitigate physiological and photochemical damage caused by ramulosis in cotton was confirmed, as the fungi improved plant growth and stomatal index and density, increased net photosynthetic rate (A) and carboxylation efficiency (A/Ci), and decreased photochemical stress (ABS/RC and DI0/RC) and oxidative stress by reducing enzyme activity (CAT, SOD, and APX) and the synthesis of malondialdehyde (MDA). Control plants developed leaves with a low adaxial stomatal index and density to reduce colonization of leaf tissues by C. gossypii var. cephalosporioides due to the absence of fungal antagonism. The Codinaeopsis sp. strain BP328EF can efficiently inhibit C. gossypii var. cephalosporioides in vitro (81.11% relative inhibition), improve gas exchange parameters, reduce photochemical stress of chlorophyll-a, and decrease lipid peroxidation in attacked leaves. Thus, BP328EF should be further evaluated for its potential effect as a biological alternative for enhancing the resistance of G. hirsutum plants and minimizing yield losses caused by C. gossypii var. cephalosporioides. [ABSTRACT FROM AUTHOR]

Although sugarcane yield is directly influenced by the availability of nitrogen (N), the efficiency of mineral N (MN) fertilization is considered to be low due to nitrate leaching and ammonia volatilization. Thus, the search for alternative sources of N that are cheaper and more consistent with sustainable farming practices has been stimulated. As chicken litter is an organic waste with the potential to supply N to major crops, we tested the hypothesis that the use of this litter as a source of organic N (ON) is as efficient as the application of MN (ammonium nitrate) in promoting the growth, nutrition, and yield of sugarcane plants grown during both plant cane and ratoon cane seasons. Experiments were conducted in a 5 × 5 × 2 subdivided plot scheme in the growing area of the Denusa Mill, Destilaria Nova União S/A, located in the midwest region of Brazil, with treatments consisting of five doses each of MN (0, 40, 80, 120, and 160 kg ha−1) and ON (0, 2, 4, 6, and 8 T ha−1), evaluated in two crop seasons (plant cane-2019/2020 and ratoon cane-2020/2021). The application of different doses of MN or ON influenced the height and number of tillers of sugar cane plants, and the application of ON, supplied by chicken litter, to this crop was as efficient as that of MN in promoting plant growth. MN and ON also increased the leaf content of N, P, and K; moreover, the absence of one source of nitrogen was compensated by the other. ON application (up to 4.8 T ha−1) also increased sugarcane yield in addition to promoting growth. Furthermore, this study highlighted the superior quality of the regrowth observed in the IACSP95-5094 cultivar, which manifested in increased tillering and stem diameter, resulting in consistently higher yields in the ratoon crop. [ABSTRACT FROM AUTHOR]

Treatments that increase the germination potential and vigor of Glycine max seedlings are continuously being stimulated, with the aim of achieving a higher percentage of emergence and better performance in the field. Considering the relationship of tryptophan with germination-associated phytohormones, this study tested the hypothesis that exogenous supply of tryptophan to soybean seeds can affect germination, physiological vigor, and the accumulation of primary and oxidative metabolism molecules in seedlings. Soybean seeds were exposed to soaking solutions containing different concentrations of the amino acid (0, 25, 50, 100, and 200 µM), and the seedlings were evaluated at three time periods, at 8 h after sowing (HAS), and 5 and 14 days after sowing (DAS). Treated seeds showed better germination fitness and seedlings showed greater vigor, and these parameters increased with increasing concentrations of tryptophan. In the initial hours and days of germination process evaluation (14 HAS and 5 DAS), the activities of starch metabolism enzymes (α- and β-amylase) tended to be higher, resulting in increased contents of sucrose, reducing sugars, and total soluble solids at 8 DAS, constituting an important metabolic effect for seedling growth. On the other hand, the induction of germination and vigor promoted by exogenous tryptophan in soybean seedlings occurred by stimulating the metabolic pathways of oxidative stress, resulting in increased concentrations of H2O2, malondialdehyde, and proline in the tissues. Additionally, it led to increased activities of the antioxidant enzymes superoxide dismutase and ascorbate peroxidase. These parameters were responsive to increasing supplied concentrations of tryptophan. Thus, the metabolic stress in soybean seeds induced by auxin seems to be an important inductive pathway for germination and vigor of G. max seeds. [ABSTRACT FROM AUTHOR]

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