Agriculture has caused numerous concerns regarding the preservation of natural resources. In this context, agroforestrysystems are emerging as a more sustainable alternative. The present study aimed to evaluate growth characteristics, radiation use efficiency, biomass partition, andyieldofsoybean grown in two agroforestrysystemsand full sun. A field experiment was conducted in Southern Brazil during the 2014/2015 crop year, in which transmissivity of solar radiation, leaf area index, radiation use efficiency, andyieldofsoybean were evaluated. The solar radiation dynamics varied among the study factors, mainly due to the agroforestry arrangements. Shading influenced the leaf area index, radiation use efficiency, biomass partition, andsoybeanyield. Based on the soybeanyield values generated in this study, the use of more spaced agroforestry arrangements and Peltophorum dubium forest species is recommended. However, because the yield values were below the expected levels, it is not yet possible to confirm the full potential ofsoybean crop inagroforestrysystems. Thus, new studies should be conducted in order to generate alternatives that make soybean cultivation feasible inagroforestrysystems, such as assessing the use of more spaced agroforestry arrangements, the insertion of the soybean crop in the initial years of cultivation ofagroforestry, as well as reduce intraspecific competition by decreasing the plant population of the crop.
system may enhance its sustainability. This study aimed to evaluate the yield components, yieldand grain quality ofsoybean cultivars, in an agroforestry system containing Eucalyptus grandis. A complete randomized block design, in a split-plot arrangement, with three replications, was used. Four soybean cultivars were allocated into the plots (BRS 359 RR, BRS 360 RR, BMX Potência RR and NA 5909 RR). The subplots consisted of five positions between the rows of E. grandis (spaced in 28 m - close to the trees on the east and west sides, intermediate position on the east and west sides and at the center of the row). The yield components andsoybean grain yield reduce significantly the closer the plants are seeded to the rows of E. grandis. However, the oil and protein contents insoybean grains are not influenced by the position between rows, regardless of the cultivar. Among all evaluated cultivars, NA 5909 RR presents the best agronomic performance in the agroforestry system containing eucalyptus.
Agroforestrysystems are characterized by the use of woody tree species in association with agricultural crops, simultaneously or alternately in time and space (Magalhães et al., 2013; Melloni et al., 2018). Inagroforestrysystems, tree species can make microclimate conditions more suitable for coffee, and increase crop yield; provide greater input of plant residues on the soil surface, which may contribute to greater soil protection and decreased erosion losses; increased organic matter content and soil fertility, in addition to improved soil physical quality (Carmo et al., 2014; Guimarães et al., 2014; Araújo et al., 2015; Souza et al., 2017).
The system that used cowpea and Stylosanthes sp. showed low production of biomass for the second crops in 2014 and 2015 (Figure 2). Cowpea plants showed fast initial growth, but with a short phenological cycle, resulting in unsatisfactory biomass yieldand soil cover rate. Stylosanthes sp. plants showed slow initial growth, which did not allow their use for biomass yieldin the second crop. Another negative factor of this species was the difficult control with herbicides used in desiccation, which led to a significant regrowing during soybean grown in succession planting. The low-biomass production of Stylosanthes sp. was also observed by Dantas et al. (2015), with DM amount of 97.5 kg ha -1 , which was a disadvantage in comparison
ABSTRACT: Brazil is the world’s main sugarcane producer and the production system has changed abiding to legal and technical recommendation. In Piracicaba many smallholders grow sugarcane in steep areas. Under such situation, mechanization at harvest makes cultivation impossible. This work assess the viability ofagroforestrysystems on joining crop production and conservation of natural resources. Soils at 12-20% slope class were identified, tree species which could be cultivated along with sugarcane were selected, and the design of the systems to be adopted was evaluated. Identified area occupies 11,556 ha and the most representative soil types are Typic Kandiuldult and Lithic Hapludoll. The exotic species coconut, eucalyptus, pejibaye and rubber, and eight native species have potential to be grown in contourhedgerows with sugarcane. Initial planting of exotic, domesticated trees is recommended, and gradual introduction of native, non- domesticated species, can be set according to their ecological requirements.
Mineral fertilizer management is one of the most important agronomic techniques applied in papaya cultivation, which generally extracts large amounts of nutrients from soil, especially nitrogen, which is the nutrient required in larger quantities throughout the crop cycle (MARINHO et al., 2010). Traditionally, it is used different N sources for papaya nitrogen fertilization, such as ammonium nitrate, ammonium sulfate, and most commonly, the urea, as observed in studies developed by Santos et al. (2014) and Santos et al. (2016). However, these soluble N forms are more susceptible to losses to the environment through ammonia volatilization and nitrate leaching (NOELLSCH et al., 2009).
The species A. auriculiformis A. Cunn. ex Benth. and A. mangium Willd may be adequate to formation of energy forests, because of their rapid growth rate and high wood biomass production (BARROS et al., 2009; KRISNAWATI et al., 2011). However, the best understanding of these species performance in terms of energy production in the Amazonas climate and soil conditions still need improvement. In this context, the present study aimed to answer three principal questions: i) Are there differences in terms of energy production between the species A. auriculiformis and A. mangium? ii) If such differences exist, which characteristics most contribute to them? and iii) Which of the species would be the more indicated to plant energy forests in the Amazon region? Thus, aim of the present work was to investigate growthand energy productivity of Acacia auriculiformis and Acacia mangium in short- rotation forest plantations in the Amazonas state.
(Figure 1, Tables 1 and 5). This interpretation is in agreement with the literature, which states that lime application on the surface is efficient in impeding a surge of exchangeable Al; however, it shows limitations at greater depths (Rheinheimer et al., 2000; Caires et al., 2008). The effects of mechanical intervention on the soil structure at the beginning of the experiment diminished three years after setting up the NT (Miotto, 2009) and were totally mitigated after five years (Tables 2 and 5). This fact reaffirms the interpretation that certain soil physical properties subject to mechanical intervention have the capacity to be resilient in some situations (Vezzani & Mielcnizuc, 2009). Nevertheless, soil acidity, if not neutralized, will continue without change at greater depths, which is a limiting factor for soybean root growth (Figure 1) and will have yield consequences (Table 4). Barriers to soybean root growth cannot be explained only by Ds and RP variations at greater depths because these properties are very similar in all the treatments evaluated. It was observed that soil layers or zones which are chemically poor hinder root lengthening and branching in the soybean crop, limiting its yield. However, this was not enough to reduce dry matter production in the oat crop because oat is a more aggressive crop (Figure 1 and Table 4). Finally, the form of lime application highlights the chemical factor, which hinders root growthand distribution, especially related to Al contents at the depth of 20 cm (Figure 1 and Table 5). This is clear upon observing that in the treatments that received incorporated lime, there was root development up to 40 cm (Figure 1 and Table 5). Plant roots avoid soil zones which offer stress, especially stress linked to Al toxicity (Delhaiza & Ryan, 1995; Hodge, 2004). This response was enough for soybean grain yieldin the treatments with incorporated lime to be 482.97 kg ha -1 greater than surface lime treatment (Table 4).
The data from soil mechanical resistance to penetration (RP) were collected three and a half months after soil tillage using an IAA/Planalsucar-Stolf impact penetrometer (Stolf et al., 2011). RP determinations at plots were carried out every 0.225 m width × 0.10 m depth within the traffic band (five rows of the seed drill), totaling twenty-eight sample points. RP data were collected at depths of 0.00–0.10, 0.10–0.20, 0.20–0.30, and 0.30–0.40 m, transformed into MPa (Stolf, 1991), and analyzed per treatment at depth and considering the individual mean per depth, in addition to the spatialization of soil profiles.
with a summer without soybean); after white oats, in the system III (soybean for two consecutive years and a summer without soybean), was higher than insoybean grown after wheat, in the system I (monoculture wheat/soybean). In this case, the system I is a winter monoculture and a summer monoculture. This greater difference observed insoybean grain yield per hectare (Table 5) can be explained in part by the grain weight (Table 8) and by the of 1,000-grain weight (Table 10), which were greater in crop rotation systems compared with monoculture soybean. In this case, there was a beneficial effect of crop rotation on soybean grain yield compared with soybean grown for all the years in the same area. During this period, soybeans expressed its greatest genetic potential, relative to the other crops studied.
In this sense, the application of phosphorus in a localized way through coating soybean seeds, combined with the split application of phosphorus at the dose applied to the soil, can contribute to a more efficient use of this nutrient by the plant, coupled with the lower retention to the soil and finally contributing to achieving higher yields. Thus, the objective of this study was to evaluate the effect of split application of phosphorus doses in the soil and coating the seeds with phosphorus in nodulation, growthandyield components ofsoybean plants.
The maize (Zea mays L.) is the main crop cultivatedin mixtures system by Brazilian farmers and, the Brazilian productivity is growing with technological advancementin, in 2009 occupying the third place in the world production of the grain . Although the maize cultivation has great expression in what concerns the national or world production, it’s considered subsistence cultivation and, in general, cultivated mixed with other grains. Teófilo et al.  reported that cowpea (Vigna unguiculata L. Walp.), is an activity of great importance to the North and Northeast, both in economics with the nutrition, it’s the staple food in the diet of the poor, exerting social function. Cowpea is tolerant to the shadowing according to the results from Cavalcante et al.  that do not find decrease on the assimilation of carbon by cowpea cultivatedin mixture with manioc. Besides, because it’s a leguminous, it converts atmospheric nitrogen in nutrient available in the soil can be leveraged by the culture in the consortium.
ABSTRACT: Thermal units or degree day systems can both be used to quantify relationships between plants and air temperature. The Northern Fluminense region holds no tradition for irrigated papaya (Carica papaya L.) cropping and, because of the need for irrigation, it is important knowing its growthand development characteristics under these conditions. This study aimed to determine the relationship between growth rate of papaya plants and degree days, and its effect on crop productivity, under different irrigation levels. An experiment was set up with the cultivar “Improved Sunrise Soil 72/12”, in a randomized blocks design, with seven irrigation water depths and three repetitions; crop growthandyield parameters were evaluated. There were significant correlations between water depths and degree days. Polynomial models of 2 nd
PATRA, D.D.; BROOKES, P.C.; COLEMAN, K.; JENKINSON, D.S. Seasonal changes of soil microbial biomass in an arable and a grassland soil which have been under uniform management for many years. Soil Biology and Biochemistry, v.22, p.739-742, 1990. PEREZ, K.S.S.; RAMOS, M.L.G.; McMANUS, C. Carbono da biomassa microbiana em solo cultivado com soja sob diferentes sistemas de manejo nos cerrados. Pesquisa Agropecuária Brasileira, v.39, p.567-573, 2004
recorded, number that was then considered ET to start insecticide spraying at that crop. At cotton, only 2.08 whiteflies per leaf were responsible for 30.84% ofyield loss (ALENCAR et al., 2002). Differently, JEON et al. (2009) observed a higher tolerance on cucumber plants when fruit damage only occurred from 63 days after Trialeurodes vaporariorum infestation. This indicates a great variability of plant response to whitefly injury. Therefore, new trials with different soybean cultivars and climatic conditions are also important since this kind of variation in the results might also occur among different soybean cultivars and areas where the crop is cultivated. Nevertheless, our data are the first report on soybean response to whitefly attack and can be taken as a primary result for future researches.
The experimental design was randomized blocks with four replicates, and the treatments were composed of three maize hybrids (P1630, LG6030 and P30F53) cultivatedin monoculture and intercropped with two soybean cultivars (TMG7062 and P95R51), resulting in nine treatments (P1630+TMG7062, P1630+P95R51, P1630, LG6030+TMG7062, LG6030+P95R51, LG6030, P30F53+TMG7062, P30F53+P95R51 and P30F53), and 36 plots of 72 m² (3.6 x 20 m). These plots were subdivided into two usable areas with 36 m² (3.6 x 10 m), one for evaluation of silage yield components and the other for evaluation of grain yield components. The observation units (OU) consisted of the two central rows of maize andsoybean with length of
In the second evaluation, greater differences were observed for PR among treatments, mainly at the depth range of 0.15-0.20 m. Treatments under NT showed higher values than those under chiseled soil, showing peaks close to 0.20 m in depth. Under NT and without gypsum application, soils were the most resistant to penetration. Despite not having PR peaks, chiseled soils also showed the highest values at the 0.20 m depth layer when gypsum was not applied. These results coincide with the high IR values of the same treatments. Lower PR values may be due to soil adhesion reduction after chisel breaking and increased porosity, which is responsible for a faster water flow throughout the soil profile.
Garden coffee production systems are widely practiced in the vicinity of farmers’ residences. Its praxis usually mixes crops or shade trees and some improved management can occur by planting in orthogonal patterns where shading trees are adjacent to coffee plants. This type of production system is widely used in South, South-western and Eastern parts of Ethiopia (Woldemariam et al., 2003; Bossolasco, 2009). In Garden coffee, the most representative production system, coffee is intercropped with fruits, herb, cash crop or forage in the same unit of land (Teketay and Tegineh, 1991; Negash and Kanninen, 2015), but it is also grown under the shade of trees and shrub species, corresponding to a typical example ofagroforestrysystems. In Ethiopia, coffee is commonly grown as understory of different tree species depending on the region (Table 1), where 69 % of the trees in south-eastern region are leguminous (Teketay and Tegineh, 1991).
This report is an output from work-package 6 which contributes to the third objective. Work- package 6 focuses on the field- and farm-scale evaluation of innovation research that have arisen from about 40 agroforestry stakeholder groups created across Europe. Some research, for example tree protection options, are best determined by technical evaluations in the field. However some research questions require a modelling approach to predict, for example, the financial and economic impact of a new practice over a number of years. This report seeks to identify those agroforestrysystemsand practices which could be usefully assessed using biophysical agroforestry models such as Yield-SAFE (van der Werf et al., 2007) and Hi-sAFe (Talbot, 2011), or bio-economic models such as Farm-SAFE (Graves et al., 2011).
Guerreiro et al. (2017) analyzed the distribution of soil nutrients in the Tapajós National Forest using geostatistics, and adjusted the exponential model for pH (H 2 O) and zinc, the Gaussian model for phosphorus and copper, and the spherical model for potassium and manganese. All of these chemical attributes presented a moderate spatial dependence, while carbon, nitrogen, sodium, calcium, magnesium, aluminum, and iron showed no spatial dependence, which differs from the results in this study. The authors suggest that PNE occurs because the spacing between samples is larger than necessary to detect spatial dependence.