Lunar escape systems /LESS/ feasibility study, volume 2 Final technical report

Lunar escape systems feasibility stud

Caracterização climática das regiões produtoras de batata no Brasil.

bitstream/item/33531/1/documento-133.pd

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

Development of maize and palisadegrass plants cultivated in intercrop under water deficit

The objective of this work was to evaluate the development and productive traits of palisadegrass single cultivated or intercropped with corn, in addition to corn intercropped with pasture, under water deficit at different development stages of the plants. It was used a complete block experimental design with split plots and three replicates. Periods of water deficit were placed in the plots and types of cultivation were placed in the subplots. Irrigation was stopped at germination and initial tillering of palisadegrass and at V4 and V15 stages of corn and returned when soil moisture was 40% of available water capacity. Tiller density and palisadegrass height were evaluated weekly. Dry matter (DM) of fractions of herbage mass as well as leaf area of the plants were evaluated at corn tasseling and when grains reached physiological maturity. Components of corn production were determined in the second sampling. In palisadegrass, water influenced only tillering, which was reduced in the plots in which water defict was forced at the moment of germination or at the beginning of tilering, in both cultivation systems. Plant height and DM production were affected only by cultivation, reducing when intercropped with corn. Evaluated production components did not influence corn grain productivity, which was similar in all treatments (average of 10,145 kg/ha). Palisadegrass plants produce more DM in single cultivation than intercropped with corn. Water deficit during germination and initial tillering reduces tillering of palisadegrass during establishment phase. Water deficit, applied in this trial, does not reduce DM yield in palisadegrass or corn