Nitrogen supply method affects growth, yield and must composition of young grape vines (Vitis vinifera L. cv Alicante Bouschet) in southern Brazil.

The aim of this study was to evaluate yield and chemical composition of the must in grapevines subjected to Nitrogen (N) supply methods in sandy soils. The vineyard cultivar was ?Alicante Bouschet? (Vitis vinifera L.) grafted on 1103 Paulsen rootstock, in southern Brazil. The treatments consisted of the application of 20+20 kg N ha−1 without irrigation (NWI), 20+20 kg N ha−1 followed by irrigation (NFI), 20+20 kg N ha−1 via fertigation (NF), 20 kg N ha−1 via fertigation (½NF), and a control (C) without N application. The study was conducted during four crop seasons. Leaves were collected at flowering and veraison to determination N concentration. Stem diameter, grape yield and its components were determined. In the must were evaluated the total soluble solids (TSS), pH, total titratable acidity (TTA) and total anthocyanins (TA). The concentration of nitrate and ammonium in soil solution was determined. N application followed by irrigation or N supplied via fertigation provided to the vines larger stem diameters and leaf N concentrations, in most crop seasons. Grapevines submitted to N application via fertigation or followed by irrigation presented higher yields than conventional application without irrigation, and between two and three times higher than the control. N supply methods little affected total soluble solids contents. The application of N to the soil, regardless of the N supply method, decreased the anthocyanin concentration in the grape must, due to the dilution effect on the pulp/skin ratio, promoted by the yield increase

Integrated crop–livestock systems in paddy fields: New strategies for flooded rice nutrition

Integrated crop–livestock systems (ICLSs) appear as a good alternative to increase nutrient use efficiency (NUE) in rice (Oryza sativa L.) through the improvement in nutrient cycling and soil chemical attributes in paddy fields. The objective of this study was to evaluate the impact of an ICLS on soil chemical attributes and on the fertilization requirement of N, P, and K by flooded rice in the Brazilian subtropical region. Nutritional status, yield, and NUE of flooded rice were evaluated by fertilization trials through rice response to different fertilization rates of N, P, and K. Soil chemical attributes were evaluated at the beginning of the experiment and 30 mo later. Different fertilization rates were applied in two systems: (a) a conventional system (CS), based on intensive tillage, rice monocropping and winter fallow, and (b) ICLS, characterized by no-tillage and winter cattle grazing in annual ryegrass (Lolium multiflorum Lam.) pasture. Rice shoot accumulation of N, P, and K was greater under CS than ICLS at all fertilization levels. On the other hand, higher rice yields were observed under ICLS at almost every fertilization level, suggesting higher NUE than CS. In addition, rice yield was increased by 40% by fertilization of P and K under CS, whereas no response was observed under ICLS. These benefits were possibly related to greater nutrient cycling and greater synchronism between rice’s nutrient uptake and nutrient release of the soil. Our results indicate that the adoption of ICLS ensures greater NUE becoming a system less dependent on external inputs