F. graminearum is the main causal agent of Head blight in cereals in Argentina. This is a disease that develops during the host floral state. When the reproductive structures in the host are invaded, grains may be shriveled and reduced in weight, causing a decrease in yield. Physiological diagnostic techniques on seeds detect the damages produced by this fungus could be used to take decisions related to the quality of seed lots. The objective of this study was to evaluate the possible physiological damage caused by F. graminearum isolates in soybean seeds and wheat caryopsis. Seeds and caryopsis were obtained from plants exposed to fungal infection and were evaluated under two situations: artificial inoculations under greenhouse conditions and natural infection from fields of Santa Fe Province (33°43’22’’S; 62°14’46’’W). Seed weight, topographical tetrazolium test, standard germination test, electrical conductivity test and X-ray test were performed in soybean seeds and wheat caryopsis from each treatment. Differential behaviors of F. graminearum strains in susceptible soybean and wheat cultivars under greenhouse conditions revealed specific interactions among soybean and wheat genotypes with this fungus. F. graminearum infection in susceptible cultivars under greenhouse conditions produced a significant decrease in the physiological quality of soybean seed and wheat caryopsis. These behaviors were not detected under field conditions in the evaluated locations. All seed quality tests used in this experiment were useful to show differences in infection in soybean and wheat independently of F. graminearum infectio

Sorghum is grown in areas and environmental situations very dry and/or too hot, where produc- tivity of other cereals is uneconomical. Aiming to evaluate the production of three sorghum hybrids, because of potassium and management systems, grown in Oxisol with low productive capacity, an experiment was con- ducted in the field, in the area of the Federal Rural University of Amazonia/UFRA, Belém campus The experi- mental design was randomized in blocks, arranged in a factorial 4 x 3 x 2 with four replications. The factors were: four doses of potassium (50, 100, 200 and 300 kg ha - 1 ) as KCl, three sorghum hybrids (Qualimax, Volumax and AG 2005 - E) and two tillage systems (no - till and conventional). The tillage produced a higher shoot dry weight of sorghum, and the hybrid and Volumax and Qualimax had incomes above the AG2005 - E. The contents of the elements N, P, K, Ca and Mg in the leaves of sorghum grown with tillage were higher than those found in conventional tillage. Doses of potassium resulted in greater increase in MSPA tillage using 40% less potash fertilizer with the conventional system.

This study aimed to evaluate the in vitro behavior of the fungus Fusarium guttiform in different conditions of temperature and luminosity and determine the most efficient inoculation method for evaluating the resistance of pineapple to fusariosis. To determine the in vitro behavior, two experiments was performed, with the same design, conduction, and evaluation. It was used a completely randomized experimental design in a factorial arrangement of 3x3 (three temperatures and three light regimes), with five replications. The evaluations of inoculation methods were conducted in a completely randomized design with factorial arrangement 3x4 (methods x distance of inoculation). D leaves of pineapple, cultivar Pearl, were inoculated at two, five, eight and eleven centimeters from the base by the methods of infected toothpick, mycelium disc without injury and mycelium disc with injury on the leaf. There was no significant difference on in vitro behavior of the isolates analyzed. The indicated temperature and luminosity for the multiplication of F. guttiform were 25°C and 12 hours, respectively, since they showed significant my celial growth and increased production of reproductive structures. The indicated method for evaluation of resistance to fusariosis in pineapple was the inoculation by infected toothpick at a distance between 2 - 11 cm from the base of the leaf. It becomes necessary to perform an injury at the site to be inoculated for the infection of the pathogen F. guttiform occurs.

This research aimed to evaluate the physiological quality of pepper (Capsicum chinense Jacq.) var. Bode Vermelha seeds, obtained from fruits at different ripening stages. The fruits of C. Chinese were separated according to the ripening stages, based on pericarp color (green fruits – stage 1, orange fruits – stage 2, light red fruits – stage 3, red fruits – stage 4, and carmine-red fruits – stage 5). To evaluate the ripeness and the physiological quality of the seeds were determined the biometric characteristics of the fruits and seeds, mass of thousand seeds, seeds water content, electrical conductivity, standard germinations test, speed of germination index, percentage of normal seedlings, speed of seedlings formation, accelerated aging, and seedling length. The characters length, diameter, weight, and number of seeds of the fruits and length, width, thickness, and mass of the seeds were analyzed by the estimated parameters using descriptive statistics. For the other variables was used the completely randomized design. The results were submitted to variance analysis and comparison of means by the Scott-Knott test at 5% probability. The ripeness stage affects the physiological quality of C. chinense Jacq. var. Bode Red seeds, being the seeds from red (stage 4) to carmine-red (stage 5) fruits those with the best performance thus, they are physiologically ripe, being the most indicated to seeds obtaining.

In order to determine the water requirement and crop coefficient for the different phenological stages on corn plants ( Zea mays L.) and cowpea plants ( Vigna unguiculata (L.) Walp) in intercropping and sole cropping systems under the climatic conditions of the Brazilian semiarid. The experiment was conducted in the city of Petrolina, PE. Shoots total dry mass and photosynthetically active radiation intercepted for both crops were monitored. Furthermore, it was obtained the evapotranspiration (ETc) by the soil water balance method. With these data and reference evapotranspiration it was obtained crop coefficient (Kc), which were subsequent- ly used to adjust models as a function of accumulated degree days. With the results, it was found the water re- quirements from maize and cowpea intercropped system were greater than the sole system. Kc in the inter- cropped system was 0.90, 1.30, 1.20 and 0.72 for maize and 0.86, 1.30, 1.21 and 0.91 for cowpea, respectively, for the vegetative, flowering, grain filling and ripening stages. In the sole system, these values were, 0.86, 1.23, 0.97 and 0.52 for maize and 0.68, 1.02, 1.06 and 0.63 for cowpea in those phases mentioned. The variations of the Kc values for both systems and cultures have been associated to the increase of biomass and light intercep- tion. The Gaussian model adjusted properly described the relationship between Kc and accumulated degree days.

Cultivars of the genus Nopalea are known in Brazil for being tolerant to cochineal carmine attacks, thus making the cultivation of this genus a promising alternative for mitigating the negative effects of this insect on the production of biomass. With the objectives of characterizing morphologically spineless forage cactus varieties and identify morphological characteristics that may be the focus in spineless forage cactus breeding programs, an experiment was conducted in a completely randomized block design with 11 treatments and four replications. The variety Alagoas showed the highest values of weight, area and volume of cladodes. The varieties Negro Michoacan F7 and V7, Tamazunchale V12 showed the highest values of the cladode area index, the total volume of cladodes and total fresh mass production. The varieties Negro Michoacan V7 and F7 presented the highest water use efficiency and dry mass yield. Cladode volume showed the highest correlation coefficients with the fresh weight of cladodes. Aiming the release of varieties for biomass production, varieties Negro Michoacan F7, V7 and Tamazunchale V12 may substitute the Miúda variety. The number and cladode area index may be used as criteria for selection of superior varieties in breeding programs.

The selection of common bean lines for seed coat standard, sanitary and physiological quality seed is recent in breeding programs. The objectives of this research were to evaluate if common bean lines differ for seed coat standard, sanitary and physiological quality seed, to investigate the correlation between these characters and to select common bean lines with high seed quality. For this, 16 inbred common bean lines were evaluated in normal rainy growing season. The common bean lines showed significant difference for the weight of thousand seeds, seed coat color, lignin content, length, width and thickness seeds, Fusarium sp. incidence, germination, first germination count, accelerated ageing, length of shoot, root and total of seedling, dry matter of shoot and total of seedling and emergency of seedling in field. A positive correlation coefficient was found between emergency of seedling in field and germination (r = 0.650), first germination count (r = 0.600), accelerated ageing (r = 0.793) and electric conductivity (r = 0.635). The indirect selection by germination, first germination count and accelerated ageing is effective to identify common bean lines with the highest emergency of seedling in field and germination. The selection of TB 02-07, SM 1810, Carioca, LP 08-90, SM 1107, LP 07 -80, Pérola, CNFP 10104 and TB 02-24 lines is recommended for use in controlled hybridization programs for improvement of news common bean cultivars of high seeds quality.

The classification of the onion made based on the diameter of the bulbs and the quality measured by soluble solids, titratable acidity, relation soluble solids /acidity e a pungency due to nitrogen and planting times were evaluated in two experiments conducted from december 2011 to April 2012 and August tha december to 2012, horta in the Department of Plant Sciences Universidade Federal Rural do Semi-Árida em Mossoró-RN. The experimental design was a randomized block with four replications. The treatments consisted of N rates: 0, 34, 67, 101, 134 and 168 kg ha -1 N. Each experimental unit consisted of a bed of 3,0 x 0,8 m, satisfaction eight rows of plants spaced 0.10 x 0.10 m. Was used as floor area, the six central rows of plants in the flowerbed. The bulb pungency increased with the supply of nitrogen to the dose of 93 kg ha-1 . Acidity and soluble solids reduced with the application of nitrogen. The onion planting in August 2012 favored the production of better quality bulbs.

The mechanical harvesting causes injuries on seeds and may affect their quality. Different threshing mechanisms and their adjustments may also affect the intensity of impacts that machines cause on seeds. So, this study aimed at diagnosing and evaluating the effect of two combines: the first one with a threshing system of axial flow and the other one with a threshing system of tangential flow, under adjustments of concave opening (10 mm, 30 mm and 10 mm for a combine with axial flow and 3.0 mm, 15 mm and 3.0 mm for a combine with tangential flow) and three cylinder rotations on the quality of soybean seeds harvested at two moisture contents. Soybean seeds of cultivar 'ND 4910' were harvested at 16.6% moisture (mid - morning) and 13.7% moisture in the afternoon. The seeds quality was evaluated by germination tests, germination speed index (GSI), germination rate, moisture content, percentage of purity and vigor by tetrazolium test. Despite the combine, the results showed that the mechanical injury has most reduced seeds quality, at 16.6% moisture content, concave opening of 30 mm (axial) and 10 mm (tangential) and cylinder rotation of 1100 rpm (axial) and 1000 (tangential), both with the highest rotations used. The combine with tangential flow had the highest degree of seeds purity. When seeds moisture content at harvest was close to 13.7%, there was the highest seed injury, while, at 16.6%, there was the highest number of crushed soybeans, regardless the combine adjustment.

Castor produces racemes primary, secondary, tertiary, among others, whose contributions to the overall productivity differ. In this context, the aim was to evaluate the agronomic characteristics and to deter-mine the influence of the order of racemes and nutrient sources on yield of castor bean. Thus, under field con-ditions, in the municipality of Remigio, Paraíba State, an experiment with BRS Nordestina cultivar was carried out in randomized blocks design arranged in 5 (different sources of organic manure: without organic manure, compost, compost enriched with rock powders and manure and mineral complete) x 4 (orders of racemes pri-mary, secondary, tertiary and quaternary) factorial experiment, with four replications. During the experiment, plant height and insertion of racemes were evaluated, length and number of racemes, early blooming and matu-ration of racemes. After harvesting, the following variables were determined: mass of racemes, number of grains per plant, yield, weight of hundred grains, length and width of the grains and the contribution of differ-ent orders of racemes in total yield. The growth of castor bean increased with the fertilizing, especially for or-ganic compounds. The first inflorescences were emitted in castor bean plants fertilized organically. The mass of racemes, the number of grains per plant and productivity were higher in racemes of secondary and tertiary orders. The length and width of the grains was higher in primary racemes. The highest yields were obtained with the use of organic sources.