Open Access Original Research Article

Maize Response to Leguminous Biomass Composted with Phosphate Rocks in the Northern Zone of Tanzania

Mawazo Shitindi, Kokoasse Kpomblekou-A, Wendell H. McElhenney, Ramble Ankumah, Johnson Semoka, Mateete Bekunda, Conrad Bonsi

Journal of Experimental Agriculture International, Page 1-15
DOI: 10.9734/jeai/2019/v35i430209

A study was conducted to evaluate maize response to leguminous biomass composted with phosphate rocks (PRs) in a split plot design. Field experiments were conducted at Wang’waray Farmers Training Center (F.T.C) located in Babati District of Manyara region in the Northern zone of Tanzania between December 2013 and June 2015. Three leguminous (Crotalaria juncea, Lablab purpureus and Mucuna pruriens) strips were cultivated in 2013/14 to produce a biomass which was harvested at flowering to early podding stage and air dried.  Air-dry biomass was composted with PRs from Minjingu (medium reactive PR) and Panda Hill (low reactive PR). Maize response to different treatments was evaluated across the field strips in 2014/15 season. The strips previously used to produce leguminous biomass were used as main plots and each strip was divided into seven subplots receiving different treatments at random. A medium term maize variety SC. 627 was used as a test crop. Average maize grain yields obtained from Crotalaria, Lablab and Mucuna strips reached 5.3, 4.5 and 4.0 t ha-1, respectively and were statistically different (P=.05). Application of Minjingu or Panda Hill PR alone didn’t increase maize grain yield above the control while Minjingu PR applied with urea or composted with biomass increased maize grain yield by 2.40 and 1.58 t ha-1, respectively above the control. Application of Panda Hill PR with urea or composted with biomass increased grain yield by 1.20 and 1.06 t ha-1, respectively above the control. The observed differences (0.82 and 0.14 t ha-1) were not statistically significant indicating that biomass composted with PR was as effective as the PR applied with urea.

Open Access Original Research Article

Effect of Sugar and Alcohol Industry Byproducts on Pre-Emergence Herbicide Efficacy

Ana Victoria Jerônimo, Rafael Pires da Silva, Bruna Ferrari Schendenffeldt, Andreia Cristina Silva Hirata, Patricia Andrea Monquero

Journal of Experimental Agriculture International, Page 1-10
DOI: 10.9734/jeai/2019/v35i430210

The present study evaluate the effects of vinasse and filter cake on the efficacy of indaziflam, saflufenacil, and sulfentrazone for the control of morning glory (Ipomoea triloba L.) and crabgrass (Digitaria horizontalis Wiild), as well as the effects of these byproducts on the emergence of these weeds. The experiments were established in a greenhouse with a completely randomized design and four replications at the Agricultural Science Center, Sao Paulo, Brazil, between May 2017 and May 2018. In the first assay, four herbicide doses: indaziflam (0, 37.5, 75, and 150 g ai ha-1), saflufenacil (0, 42, 84, and 168 g a.i ha-1), and sulfentrazone (0, 300, 600, and 1200 g ai ha-1) were applied for pre-emergent weeds in three soil covers (without byproduct, with vinasse, and with filter cake).In the second assay, seven treatments were evaluated, comparing the effects of the different vinasse and filter cake doses, and absence of byproduct on the weeds emergence. When the doses required for 80% effective control were considered, the results showed that for indaziflam, the filter cake negatively affected crabgrass control. In contrast, vinasse had a positive effect on morning glory control by saflufenacil. For sulfentrazone, the filter cake had a negative effect, requiring twice the dose used on the treatment without byproduct for effective morning glory control. Relative to assay 2, the vinasse addition affected the emergence of morning glory but not of crabgrass; however, the filter cake increased the weed biomass accumulation. Vinasse and filter cake byproducts can negatively or positively affect the performance of pre-emergence herbicides, according to the active ingredient used. However, these effects occur at doses below those recommended for the herbicides. Byproducts can affect the emergence and the weed biomass accumulation.

Open Access Original Research Article

Granulometry and Stability of Aggregates in Different Land Uses in the Santa Catarina Plateau of Southern, Brazil

Kristiana Fiorentin dos Santos, Fabrício Tondello Barbosa, Ildegardis Bertol, Romeu de Souza Werner, Neuro Hilton Wolschick, Luran Monteiro Museka

Journal of Experimental Agriculture International, Page 1-6
DOI: 10.9734/jeai/2019/v35i430211

The aim of the present work was to determine the granulometry and stability of aggregates in different types of land use in the Santa Catarina Plateau of southern, Brazil. The research was conducted on Capão Alto, Santa Catarina, Brazil. The land use types selected were natural forest (NF), stands pine (SP), crop-livestock integration (CLI), and burned natural rangeland (BR). The definition of the collection points in the field was performed by means of a random sample survey, with nine sampling points by type of use. The stability of aggregates in water, expressed by the mean geometric diameter of aggregates (MGD), was performed after separation of the larger aggregates in smaller aggregates by a set of sieves with 8 and 4.76 mm. Subsequently, these aggregates were fractionated by means of a set of sieves of 4.76; 2.00; 1.00; and 0.25 mm by means of shaking submerged in water. The levels of sand, silt and clay presented differences between the types of land use. MGD ranges from 4.43 to 5.70 mm in NF; from 4.06 to 5.81 mm in SP; from 3.00 to 5,45 mm in CLI; e 4.35 to 5.57 mm in BR. In general, the results showed that MGD varied little in the different types of use, and in all treatments there was a trend of decreasing soil MGD with increasing depth.

Open Access Original Research Article

Floristic Composition in Chronosequence in Atlantic Rainforest Fragments

Andréa V. F. Pinto, Maria A. M. Silva, Maria J. H. Leite, Girlânio H. Silva, Ana V. L. Leite, Ladivânia M. Nascimento, Ana C. B. Lins e Silva, Maria J. N. Rodal

Journal of Experimental Agriculture International, Page 1-13
DOI: 10.9734/jeai/2019/v35i430212

Secondary forests play an important role in tropical landscapes and have important ecological functions such as the ability to accumulate biomass. Although the literature points to the convergence between primary and secondary forests, however there are few studies in Atlantic Rainforest in a chronosequence to show it. This study aimed to characterize the changes of floristic composition in a chronosequence (5, 16, 24, 30 years of regeneration and mature forest) in the Atlantic Rainforest. In each forest 30 plots of 10 × 10 m were installed for canopy sampling, and within these 100 m2 were installed plots of 5 × 5 m for sampling the woody sub-forest at the lower left corner. The growth habits analyzed were arboreal (diameter at breast height, DBH ≥ 5 cm), shrubs (DBH < 5 cm and stem diameter at ground level > 1 cm), herbs, epiphytes and climbing plants. The results suggest that from 16 young forests tended to converge with the mature forest in terms of the proportion of growth forms.

Open Access Original Research Article

Zoning of Water Deficiency Risk for Conventional Cotton in Mato Grosso

Elizangela Selma da Silva, José Holanda Campelo Júnior, Francisco de Almeida Lobo, Ricardo Santos Silva Amorim

Journal of Experimental Agriculture International, Page 1-12
DOI: 10.9734/jeai/2019/v35i430213

Cotton agroclimatic zoning is an essential tool to establish the most favorable periods for its cultivation, when the environmental conditions are more propitious, in order to reduce risks in agricultural activity. The objective of this work was to develop the zoning of the risk estimation of cotton yield reduction in the state of Mato Grosso, using the FAO method. Cultivars of early, medium and late cycles were considered, with four sowing dates (12/11, 12/21, 1/01 and 1/11) and three available water capacities (60, 140 and 200 mm). Results were specialized by ordinary kriging. The southernmost regions of the state presented the highest reduction risks, due to the lower precipitation in these areas. Sowing period 1 presented the lowest yield reduction risk, and the late-cycle cultivar in season 4 was the one that presented the highest reduction risk. Trough the validation of the obtained results, it can be considered that the methodology adopted in this work to verify the risk of yield decrease proved to be efficient.