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71.
72.
Fernando Shintate Galindo Marcelo Carvalho Minhoto Teixeira Filho Salatiér Buzetti José Mateus Kondo Santini Eduardo Henrique Marcandalli Boleta Willian Lima Rodrigues 《Journal of plant nutrition》2020,43(8):1057-1069
AbstractNew studies are needed to optimize the nitrogen (N) amount that can be applied to utilize the Azospirillum brasilense benefits. In addition, information regarding the interaction between the urease inhibitor and biological nitrogen fixation (BNF) and how they affect the macronutrients accumulation are also needed. We evaluate the effect of N sources and doses associated with A. brasilense regarding the macronutrients accumulation in straw and grains and wheat grain yield in tropical conditions. A randomized block experimental design was used with four replications in a 2?×?5?×?2 factorial arrangement as follows: two N sources (urea and urea with urease enzyme inhibitor NBPT; five N doses (0, 50, 100, 150, and 200?kg ha?1) applied in topdressing; with and without A. brasilense inoculation. We found that an increase in N doses positively influenced the accumulation of macronutrients in straw and grains and the wheat grain yield. N sources have similar effects. Inoculation with A. brasilense increased accumulation of Mg and S in straw and P, Ca, and Mg in grains, regardless of the N dose. The inoculation with A. brasilense associated with 140?kg ha?1 of N increased wheat grain yield. The inoculation can contribute in a more sustainable way to wheat nutrition and optimizing N fertilization. 相似文献
73.
Renan Francisco Rimoldi Tavanti Grace David Queiroz Anne Caroline Da Rocha Silva Walmor Moya Peres Amanda Pereira Paixão Fernando Shintate Galindo 《Archives of Agronomy and Soil Science》2020,66(6):743-762
ABSTRACTThis study aimed to assess the physiological and biochemical responses of cotton plants to manganese (Mn2+) nutrition. Four cotton genotypes (G1 – TMG 47; G2 – FM 975 WS; G3 – TMG 11 WS and G4 – IMA 8405 GLT) were grown in nutrient solution under two Mn2+ concentrations (2 and 200 µmol L?1) for 10 days. No visible symptoms of Mn2+ toxicity were observed in the genotypes tested. All genotypes showed a marked increase in leaf chlorophylls, pheophytins, carotenoids, sucrose and total sugars concentration in response to high Mn2+ in a nutrient solution. However, the net photosynthetic rate, stomatal conductance, internal carbon dioxide concentration and transpiration decreased in genotypes G1 and G2 growing under 200 µmol L?1. Antioxidant enzymes such as superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR) activities increased in genotypes G1, G3 and G4. Cotton genotypes showed an increased leaf antioxidant and sugar metabolism as a possible strategy to mitigate oxidative stress. The decrease in the net photosynthetic rate and stomatal conductance; the increased antioxidant enzymes activities (SOD, APX and GR); and the increase in leaf sucrose and total sugar concentration were the main physiological and biochemical responses in cotton plants to Mn2+ stress. 相似文献
74.
Vallejo F García-Viguera C Tomás-Barberán FA 《Journal of agricultural and food chemistry》2003,51(13):3776-3782
Changes in phenolic compounds, total glucosinolates, and vitamin C were monitored during the productive period along five inflorescence development stages of three broccoli commercial cultivars (Marathon, Monterrey, and Vencedor). In an attempt to identify differences due to agronomic factors, broccoli cultivars were grown under different sulfur fertilization with poor (15 kg/ha) and rich (150 kg/ha) rates. Phenolic compounds and vitamin C concentrations showed, in all broccoli cultivars, a rising trend from the first stage until the over-maturity stage, both for rich and poor sulfur fertilization. Significant differences were detected in the first two stages between rich and poor sulfur fertilization in total glucosinolates for all broccoli cultivars, where the highest concentration was always observed in the second development stage (used as minimally processed product) during poor fertilization. With regard to the last three stages, the glucosinolate concentration in the poor sulfur fertilization started to slope down until the over-maturity stage. Where rich sulfur fertilization is concerned, the highest level was reached during the third stage (used as minimally processed product also), and after that, glucosinolate concentration decreased until the fifth stage. 相似文献
75.
Valéria Amorim Conforti Fernando Cesar Cascelli de Azevedo 《Biological conservation》2003,111(2):215-221
Jaguars (Panthera onca) have been killed by local residents within the boundaries and lands surrounding Iguaçu National Park (INP), Brazil. Both jaguars and pumas (Puma concolor) occur in the region, however, livestock predation by pumas has rarely been reported. Our objective was to assess the local perceptions about jaguars and pumas. We identified two major factors that distinguished the perceptions towards the two species: less people feared the puma than the jaguar; and most people believed that jaguars, but not pumas, were released into INP by local authorities. Interestingly, despite those major differences in these perceptions, feelings towards the two species tended to be the same. Perceptions towards jaguars were not influenced by the predation history of the properties, suggesting that the predation impact was not remarkable enough to influence local perceptions towards carnivores. This is apparently the first study on local perceptions towards large carnivores in Brazil. 相似文献
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78.
This paper discusses the results of a lichenometrical and geomorphological study of one of the few remaining active snow hollows in the central region of the Iberian Peninsula. The study area, located on a glacial shoulder, is called Hoya del Cuchillar de las Navajas. A protalus rampart occurs at the base of the hollow. Our studies, conducted between 1992 and 1998, were designed to determine the geomorphological characteristics of Hoya, the mobility of the deposits, and the characteristics of the snow cover. These data formed the basis for a study of the lichen colonization on the blocks and on the wall surrounding the snow hollow. All of the lichen species found were analyzed according to their abundance, distribution and the extent of their surface cover. Measurements of the diameter of the thalli of the species Rhizocarpon geographicum were also obtained. Thalli of this species were found to require a mean snow-free growing season of at least 95 days (13.5 weeks) per year. Maximum mean thallus diameters indicate that the protalus rampart was formed during the Little Ice Age and became inactive 130 years ago. 相似文献
79.
80.
Schiestl FP Peakall R Mant JG Ibarra F Schulz C Franke S Francke W 《Science (New York, N.Y.)》2003,302(5644):437-438
The "sexually deceptive" orchid Chiloglottis trapeziformis attracts males of its pollinator species, the thynnine wasp Neozeleboria cryptoides, by emitting a unique volatile compound, 2-ethyl-5-propylcyclohexan-1,3-dione, which is also produced by female wasps as a male-attracting sex pheromone. 相似文献