ABSTRACT Commercial exploitation of the coffee crop is one of the most important activities in the world’s agricultural sector. One of the main phytosanitary problems affecting the crop is the presence of Meloidogyne incognita. Several measures have been tested for the management of this pathogen, albeit with low efficiency. The objective of this work was to quantify the damage and losses and to manage M. incognita race 1 with Pochonia chlamydosporia and Trichoderma harzianum biological nematicides, comparing them to a chemical nematicide. The experiment was carried out in a commercial area naturally infested by the nematode and cultivated with the conilon coffee variety ‘Vitória INCAPER 8142’, clone V02. The treatments were tested with Carbofuran nematicide and with biological nematicides composed of P. chlamydosporia Pc-10 and T. harzianum ESALQ 1306. The biological products were applied alone or in combination. The lowest NPF (final nematode population) occurred in plants treated with P. chlamydosporia and Carbofuran. P. chlamydosporia was the most effective biological agent in the management of M. incognita. There was a reduction in production with an increase in the nematode population. The highest application costs of management methods for M. incognita race 1 per hectare were for three and two applications of Carbofuran and three applications of P. chlamydosporia + T. harzianum. The treatments with lowest application costs were one application of T. harzianum and one application of P. chlamydosporia. It was concluded that all treatments were efficient for the management of M. incognita race 1, causing a decrease in the roots and soil population.

ABSTRACT Sourgrass (Digitaria insularis) is one of the main species causing significant losses in Brazilian soybean production systems. Thus, this paper aimed to evaluate sourgrass interference on soybeans grown under Cerrado conditions. Three field experiments were conducted, of which the first two (E1 and E2) simulated sourgrass after pre-sowing burndown, using plants already emerged by the time soybeans were sown; whereas the third (E3) simulated both sourgrass and soybeans emerged simultaneously. Both E1 and E2 were conducted in a randomized complete block design (RCBD) with five treatments based on sourgrass infestation densities (0, 2, 4, 6, and 8 plants m-2) and four replications. In turn, E3 was also carried out in an RCBD but with treatments arranged in a 2 x 5 factorial and four replications. The first factor comprised two soybean cultivars, while the second was sourgrass density levels, just as in E1 and E2. The results showed that increasing sourgrass densities reduced soybean yield regardless of the plant growth stage when the crop was sown. Yield losses were higher when sourgrass plants were already established by the time soybean was sown. Soybean yield losses reached up to 80% under higher sourgrass infestation levels.

ABSTRACT Cowpeas (Vigna unguiculata L. Walp) are an economically and socially important legume in northern and north-eastern Brazil and can establish effective symbiosis with nitrogen-fixing bacteria. We evaluated the symbiotic compatibility and efficiency of rhizobial strains from Pernambuco semi-arid soils and determined their symbiotic stability on the IPA-206, BR 17-Gurguéia, and BRS Novaera cultivars, selected for different environments. The experiment was conducted in a greenhouse to evaluate a 3 × 28 factorial arrangement (cultivars selected for different environments × inoculation with the currently recommended strain, uninoculated plants with or without mineral nitrogen, and 25 rhizobial strains from semi-arid soils) in a randomized block design with four replicates. We determined nodule number, shoot and root dry matter, nodule dry matter by nodule number, nitrogen accumulated in the shoot by nodule dry matter, nitrogen content and accumulation in the shoot, relative efficiency of the recommended strain based on nitrogen accumulation, and shoot dry matter. Overall, the cultivars responded differently to different strains and cultivar biological nitrogen fixation potential. Strains G7.85 and BR 3262 showed potential for biological nitrogen fixation. BR 3262 was confirmed to be adequate for inoculation of different cowpea cultivars.

ABSTRACT Lignocellulosic residues are used to produce mushrooms, but they generate large amounts of spent mushroom substrate (SMS). The objective of this study was to evaluate they effect of SMS of Pleurotus ostreatus, combined with organic fertilization, on biomass production and essential oil yield of basil (Ocimum basilicum L.) plants. The fertilizer was formulated using combinations of organic compounds: SMS, organic compost (OC), and earthworm humus (EH). The treatments were applied using 35 g of the formulations, corresponding to an application of 20 Mg ha-1. The treatments used were: 100% OC; 100% EH; 100% SMS; 75% SMS + 25% OC (C1); 75% SMS + 25% EH (C2); 50% SMS + 50% OC (C3); 50% SMS + 50% EH (C4); 50% SMS + 25% OC + 25% EH (C5), and a control with no fertilizer application (CT). Plants grown with the soil fertilizers containing SMS, single or combined with OC and EH, presented higher average plant height (55.6 to 62.2 cm) and leaf area per plant (696.5 to 836.4 cm2). The treatment C3 resulted in plants with higher mean dry weight (10.9 g plant-1), and C2 resulted in the highest oil yield (5.0 kg ha-1), representing a gain of 324.8% in oil yield when compared to the control. Thus, SMS increases biomass production and essential oil yield of basil plants.

ABSTRACT Iron and zinc deficiency is one of the main problems affecting vulnerable populations in the Colombian Caribbean, thereby generating malnutrition from the consumption of foods with low content of essential minerals. The objective of this study was to evaluate the genotype-environment interaction for iron and zinc accumulation in grains in 10 cowpea bean genotypes by additive main effects and multiplicative interaction (AMMI) model and to select the most stable ones to stimulate their planting or as parents in the genetic improvement program. Nine promising lines and a commercial control were evaluated using the randomized complete block design with 10 treatments and four replications in 10 environments of the northern Colombia in the second semester of 2017 and first of 2018. The adaptability and stability analysis was done using AMMI model. The results showed highly significant differences at the level of environments, genotypes, and genotype-environment interaction for iron and zinc, demostrating a differential adaptability of genotypes in the test environments. Genotypes 2 and 3 expressed greater adaptability and stability for iron contents in the seed; while genotype 1, recorded it for zinc contents. These three genotypes outperformed the commercial control and, therefore, can be recommended for planting or be used as parents in the genetic improvement program.

ABSTRACT The work evaluated the potential for discrimination of land use and occupation around reservoirs, using spectral information obtained by multispectral, hyperspectral satellites and images obtained with an ARP (remotely piloted aircraft). The research analyzed the performance of different images classification techniques applied to multispectral and hyperspectral sensors for the detection and differentiation of soil classes around the Paus Brancos and Marengo reservoirs, located in Settlement 25 of Maio. The classes identified based on surveys in campaigns carried out in 2014 and 2015 around the reservoirs were: water, macrophytes, exposed soil, native vegetation, agriculture, thin and ebbing vegetation, in addition to the cloud and cloud shadow targets. The performance of the classifiers applied to the image of the Hyperion sensor was, in general, superior to those obtained in Landsat 8 image, which can be explained by the high spectral resolution of the first, which facilitates the differentiation of targets with similar spectral response. For validation of the supervised classification method of Maximum Likelihood, Landsat 8 (08/24/2015) and Hyperion (08/28/2015) images were used. The results of the application indicated a good performance of the classifier associated with the RGB composition of the chosen Hyperion image (bands R - 51, G - 161, B - 19) in the detection of the classes around this reservoir, producing a Kappa coefficient of 0.83. The availability of data from the Hyperion sensor is very restricted, which hinders the development of continued research, thus the use of images surpassed by RPA is extremely viable.

ABSTRACT The use of organo-mineral fertilizer is an alternative measure to mitigate salt stress in semiarid regions. Thus, the objective of this work was to evaluate the physiological indexes of peanut crops under irrigations with fresh and brackish waters and applications of organo-mineral fertilizers. The experiment was conducted from June to September, 2019, at the Universidade da Integração Internacional da Lusofonia Afro-Brasileira (UNILAB), in Redenção, state of Ceará, Brazil, using a completely randomized experimental design in a 5 × 2 factorial arrangement, with four replications. The treatments consisted of five soil fertilizers (F1= 100% NPK mineral fertilizer at the recommended rate; F2= 100% bovine manure-based biofertilizer; F3= 100% plant ash; F4= 50% mineral fertilizer and 50% bovine manure-based biofertilizer; and F5= 50% mineral fertilizer and 50% plant ash); and two salinity levels (electrical conductivities) of the irrigation water (1.0 and 5.0 dS m-1). Photosynthetic rate, transpiration, stomatal conductance, leaf temperature, internal CO2 concentration, water use efficiency, and chlorophyll index of the plants were evaluated at 40 and 54 days after sowing (DAS). Plants irrigated with fresh water presented higher stomatal conductance, photosynthetic rate, and transpiration, regardless of the fertilizer used. The use of 100% bovine manure-based biofertilizer resulted in decreases in salt stress and increases in water use efficiency at 40 DAS, and decreases in leaf temperature and increases in relative chlorophyll content at 54 DAS.

ABSTRACT Coconut meal can be an affordable low-cost alternative to noble ingredients such as corn and soybean meal in sheep diets. The objective of this study was to evaluate the effects of coconut meal inclusions, when used as a corn and soybean meal replacement, on the intake, digestibility, and nitrogen balance of sheep diets. Twenty-four male Santa Inês lambs with body weights (BW) of 26.6 ± 3.2 kg were used in the study. The animals were housed in metabolic cages and distributed in a completely randomized block design, with three treatments and eight replications. The animals received a total mixed ratio of 30% roughage (elephant grass) and 70% concentrate. The animals were fed on two experimental diets with 11% and 22% coconut meal inclusion and a control diet (without coconut meal). Dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and non-fibrous carbohydrate (NFC) intake as a percentage of BW were negatively influenced by the inclusion of coconut meal. The ether extract (EE) intake increased but did not differ between the 11% and 22% coconut meal diets. Furthermore, the digestibility of DM, CP, EE, and ADF did not differ between the two evaluated diets. The inclusion of coconut meal reduced NDF digestibility and increased that of NFC. The level of inclusion of coconut meal in the diet must be based on the EE content in the meal; keeping the EE intake below 0.16% of the BW helped to avoid limited intake of feed.

ABSTRACT Sorghum is a commonly grown plant in the Central-West region of Brazil as a second crop; however, it is grown almost exclusively as a second crop after maize in the state of Paraná (South region). The growth of sorghum crops is an option for areas or times in which the growth of maize crops can be risky. Thus, the objective of this work was to evaluate the agronomic characteristics of eight sorghum hybrids (ADV-123, ADV-114, 1G100, 50A10, 1G244, 50A40, 50A50, and 1G282) grown in three sowing times in two agricultural years: 2014 (February 20, March 02, and March 03) and 2015 (February 09, February 19, and March 01), and four maize hybrids in 2014 (DKB-330-Pro, P-3431-HX, Formula-TL, and AG-9010-Pro) and five maize hybrids in 2015 (DKB-330-Pro, P-3431-HX, Formula-TL, DKB-275-Pro, and DKB-290-Pro), in the same sowing times used for sorghum. A randomized complete block experimental design with a split-plot factorial arrangement was used, with the sowing times in the plots and the hybrids in the sub-plots. The variables evaluated were: number of days from sowing to flowering, leaf area index, 1,000-grain weight, grain yield, number of spikelets per panicle, for the sorghum crop; and number of rows per ear and number of grains per row, for the maize crop. The comparison between the two crops showed that the sorghum maintained higher production stability in the different sowing times.

ABSTRACT The use of green manure from spontaneous species has gained prominence for vegetable crops focused on environmental sustainability and is an alternative method for the Semiarid region in the Northeast of Brazil. Two experiments were conducted in two growing seasons (autumn and spring-summer), in Serra Talhada, PE, Brazil, to evaluate the effects of different amounts of biomass of Calotropis procera (roostertree) and incorporation times on the agro-economic performance of beet crops. A randomized block experimental design was used, with three replications, in a 4 × 4 factorial arrangement; the first factor consisted of amounts of C. procera biomass (5.4, 8.8, 12.2, and 15.6 Mg ha-1 on a dry basis) and the second factor consisted of times of incorporation into the soil (0, 10, 20, and 30 days before planting beet). Commercial root yield, production costs, and the following economic indicators were determined: gross income, net income, return rate, and profitability index. The use of 15.6 Mg ha-1 of C. procera biomass resulted in the highest gross and net incomes and the use of 5.4 and 12.2 Mg ha-1 resulted in the best return rates and profitability indexes in autumn and spring-summer seasons, respectively; the planting time was considered as ideal for the biomass incorporation. The spring-summer growing season resulted in a higher economic return than the autumn growing season. The use of C. procera as a green manure for beet production is economically viable, regardless of the factors evaluated.