Studies related to the absorptions and nutrient partitioning in organs of irrigated beans are scarce and very important for the improvement of different fertilization models. This study aimed to evaluate the growth of irrigated common bean in winter, through biomass production and nutrients uptake to organs and shoots. We used a randomized block design with three replications and seven composed of time periods of plant collection (10, 20, 30, 40, 50, 60 and 70 days after plant emergence) with separation in leaves, stem, flower+pod and grains. After determination of dry matter, the content of N, P, K, Ca, Mg and S absorbed by shoots and components of bean was estimated. Nonlinear sigmoid and gaussian models were fitted to characterize biomassa production and nutrient uptake during bean growth. The absorption of by bean decreasing in the following order, in kg ha-1: 138 K, 112 N, 66 Ca, 16 P, 11 S and 7 Mg, indicating the high absorption of K and N and demand of K replacement by top dressing. During the initial growth stage, leaves were responsible for 80% of macronutrients accumulation in shoots. In the final growth stage, grains exported 90, 75 and 65% of P, N and Mg absorbed, showing its high export rate.

Over the past few years, the increased use of fossil fuels as well as the unsustainable use of land, through the reduction of native forests has increased the greenhouse gas emissions, contributing defini- tively to the rise in temperature on earth. In this scenario, two environmental factors, directly related to the physiology of crop production, are constantly being changed. The first change is the increase in the partial pres- sure of carbon dioxide (CO2), which directly affects photosynthetic efficiency and the associated metabolic processes. The other change is the temperature increase which affects all the physiological and metabolic proc- esses mediated by enzymes, especially photosynthesis and respiration. Therefore, this review aims to discuss the main effects caused by increased CO2 pressure and the temperature rise in the physiology, productivity and post-harvest quality of plants with photosynthetic metabolism C3, C4 and CAM. Based on physiological evi- dence, the increased atmospheric CO2 concentration will benefit net photosynthesis, stomatal conductance and the transpiration of C3 plants, however in hot, dry and saline environments, the C4 and CAM species present an advantage by having low photorespiration. Studies show controversial conclusions about the productivity of C3 and C4 plants, and the quality of their fruits or grains under different CO2 concentrations or high tempera- tures. Thus, there is a need for more testing with C3 and C4 plants, besides of more researches with CAM plants, in view of the low number of experiments carried out in this type of plants.

The objective of this study to evaluate the nutritional value of cactus pear grown under different planting spacings and doses of cattle manure applied to soil. The experiment was implemented in an Oxisol in Guanambi, Bahia. The experimental design was randomized blocks with 12 treatments arranged in a factorial 3 x 4, four doses of cattle manure (0, 30, 60 and 90 Mg ha-1 yr-1) and three planting space, two in single rows (1,0 x 0,5 and 2,0 x 0,25 m) and a double row in (3,0 x 1,0 x 0,25 m) and three repetitions. In the planting spaces used, the same population density of 20,000 plants ha-1 was maintained. The nutritional value of cladodes was evaluated at 600 days after planting. Data were subjected to analysis of variance and subsequently comparisons were made between the means of different spacings by the Tukey Test and regression analysis for the different doses of manure and, when significant, interactions were unfolded. The manure of cattle increasingly influ- enced the content of crude protein, total nitrogen, protein and rapid intermediate degradation. There was a de- crease in hemicellulose levels, total carbohydrates, neutral and acid detergent insoluble nitrogen as a function of total nitrogen and indigestible protein. Thus, the increase in doses of manure applied to soil improves the quality of the nutritive value of forage palm and planting spaces barely influence the quality of cactus pear.

The objective of this study was evaluate the morphological variability and existing production between peanut genotypes collected from small farmers in seven counties in Recôncavo of Bahia, in addition to selecting the most promising materials. Peanut seeds (60 genotypes) were collected along the ethnobotanical survey. Each genotype was collected from a zoned farmer in the study area. Experimental design was a randomized block with four replications. For morphological analysis of growth characteristics were evaluated: main stem height, number of leaves and number of branches also have assessed them components of plant production and productivity, which were evaluated: the volume of fresh and dried vegetable, fresh vegetable pasta and dried, the diameter and length of vegetables, total number of vegetables, total number of grains and the weight of 100 grains. The data were subjected to analysis of variance and means were compared by the Scott- Knott test at 5% probability. Although not shown variability the vegetative morphological characteristics, yield characteristics are indicative of the existence of variability, and why it has become possible to preselect seven peanut genotypes collected from farmers in the Recôncavo of Bahia, which may be considered important descriptors for the distinction of superior genotypes.

The effect of plant aqueous extracts in the control of Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. the causal agent of guava anthracnose in, was evaluated in vitro with 1, 2 and 3% aqueous ex- tracts of Azadirachta indica, Nerium oleander, Ocimum gratissimum, Syzygium aromaticum. The experiment was installed in a complete randomized desing in a 3x4 factorial scheme (doses x extracts). For the evaluation, it was calculated the percentage of fungal inhibition. The experiment in vivo was conducted by applying Syzy- gium aromaticum and Azadirachta indica aqueous extract at 2 and 3%, respectively, in three different storage conditions: refrigerated with and without plastic film (PVC), and at ambient conditions. The experiment was installed in a completely randomized design, in a 2x3 factorial scheme (extracts x storage conditions). We evaluated the external appearance and severity of disease, loss of weight and Brix degrees. Syzygium aromati- cum extract at 2% provided 100% of fungal mycelial growth inhibition, and Azadirachta indica extract at the highest dosage (3%) inhibited 20.22%. In fruits, there was not significant statistical difference between the ef- fect of extracts on the external appearance and severity of disease, loss of weight and Brix degrees. In relation to the storage conditions, the ones with plastic film and refrigerated differed from the other conditions obtain- ing better external appearance and less severity of disease, lower loss of weight and higher Brix degrees.

The objective of this study was to evaluate the reaction of soybean (Glycine max) cultivars to brown spot (Septoria glycines) under different crop management methods. In this study the effects of the following crop management techniques were evaluated on five soybean cultivars (Msoy9001; Msoy8411; Conquista; Emgopa313; A7002): (a) fungicides and hormones, and; (b) time of planting (October, November and December). The experiment was set in Cristalina, GO, Brazil, in a randomized complete block design with eight replications in a factorial scheme (5 x 3 x 4). The chemical control of brown spot was tested as following: 1) Tetraconazol (T) (0.35 L ha-1) Thiophanate methyl + (TM) (0.4 L ha-1); 2) Stimulate ® [indolbutiric acid 0.005%, kinetin 0009% and giberelic acid (GA3 0.005%) (0.10 L ha-1)] + T (0.35 L / ha) + TM (0.4 L ha-1); 3) T (0.5 L ha-1), and; 4) control without any product. For each plot was evaluated the disease severity and incidence, and yield of seeds. Msoy8411 and Emgopa-313 planted in November presented the lowest amount of disease, and the highest seed yield. Considering the analysis of all cultivars, the chemical treatments that significantly reduced disease were Tetraconazol (0.5 L ha-1) and the chemical combination [Stimulate ® (0.10 L ha-1) + Tetraconazol (0.35 L ha-1) + Thiophanate methyl (0.4 L ha-1)].

The scarcity of good quality water in semiarid region has been the main limiting factor for in- creasing the irrigated area. However, due to greater availability of saline water, and reduced costs, when man- aged carefully, can be a viable alternative. The objective of this research was to study the effects of water use with low (S1 = 0,5 dS m-1) and high (S2 = 4,3 dS m-1) salt concentration on growth of melon plant. Melon (Cucumis melo L., cv Sancho) crop was irrigated with water of low and high salinity water under different management strategies: S1S2S2S2 – T1, S1S1S2S2 – T2, S1S1S1S2 – T3, S2S1S2S2 – T4, S2S1S1S2 – T5, S2S2S1S2 – T6 (the 1st, 2nd , 3rd and 4th term of these sequences correspond to different phases of crop – initial growth, flowering, fruit maturation and harvest, respectively), irrigation with S1 water throughout the crop cycle – T7 (control), varying the type of water every two days throughout the cycle (irrigation with S1 during 2 days fol- lowed by S2 1 day – T8 and with S2 during 2 days and followed by S1 1 day – T9) and irrigation with S2 water throughout the cycle - T10. The experiment was conducted in a completely randomized design with four replica- tions. The use of low and high salinity water applied in different phases of plant growth under different man- agement strategies did not affect the characteristics of melon cultivar Sancho. The cultivar Sancho tolerates irrigation water salinity up to 4,3 dS m-1, without any loss in growth and development.

In agricultural areas of Cerrado, where there is no possibility of making two cultivation to the year, areas before cultivated with soybeans or corn, remain in fallow until the next crop year, where weed inci- dence is high. In this research was aimed assess the potential for weed suppression by cover crops, when sown in the off season of annual crops. The experimental design was a randomized block with eight treatments (Urochloa ruziziensis, Pennisetum glaucum, Crotalaria juncea, Crotalaria spectabilis, Styzolobium aterrimum, Canavalia ensiformes, Cajanus cajanand Stylosanthes macrocephala + Stylosanthes capitata) in four replica- tions. The evaluations were performed at 45, 90, 135 and 180 days after the sowing (DAS), with determination of dry mass, plant density and vegetal cover over the soil afforded by cover crops and weeds. The population dynamics was evaluated by means of phytosociological parameters. It is conclude that the weed community presents variations during the development cycle of the cover crop and the greater biomass production, soil cover vegetal and weed suppression was obtained with the U. ruziziensis.

The P critical levels in plants depend from soil characteristics which reflect phosphate buffer power. In Pernambuco, soils mineralogical characteristics change at different regions where corn is cultivated. To evaluate P critical levels in corn plants in soil cultivated in different soils and contact periods of this element in the soil, aiming to study the relationships between these critical levels and P adsorption, it was realized an experiment using subsuperficial samples of a Vertissolo Ebânico órtico (VEo) (Mollisol), clay textured with predominance of 2:1 clay mineral and a Nitossolo Vermelho distroférrico (NVdf) (Nitosol), high clay content, predominantly hematitic, colleted at the semi - arid and humid regions of Pernambuco State, Brazil, respectively. The P doses were defined in function of the levels 0; 0.2; 0.4; 0.8 and 1.0 from the P Maximum Capacity of Adsorption (CMAP) of each soil and were incubated by 90; 60; 30; 15; and 0.5 days. The experiment was real- ized into a greenhouse in a factorial scheme (5x5x2), five P levels, five incubation periods and two soils, in randomized blocks delineation with three replicates each. Corn plants were more efficient to utilize P in NVdf, the soil with higher CMAP. The corn shoot critical levels decreased in accordance to the period of incubation in VEo, the soil with lower CMAP.

One of the characteristics of maize cultivation in the Northeast region of Brazil is the diversity of production systems. One can find from large companies, which adopt modern cultivars and relatively high sowing densities, to small properties, with traditional cultivars grown at low sowing densities (cultivation in pits spaced more than 1.0 m). The objective with this work was to evaluate the effects of sowing density (30, 40, 50, 60, or 70 thousand plants ha-1) on green ear yield and grain yield of maize cultivars (AG 405 and BR 106). Green ears and grain are assessed and marketed differently. Consequently the optimum densities for ob- taining each product may be different. In addition, maize cultivars may respond differently to increased density. Densities were achieved by maintaining a constant spacing between rows (1.0 m) and varying the spacing be- tween pits within the same row. Cultivars and sowing densities were combined in a factorial scheme, arranged in a random block design with five replications. The maximum yield of marketable husked green ears of culti- vars AG BR 405 and 106 were obtained with densities of 59 and 62 thousand plants ha-1, respectively. The maximum grain yield of cultivars AG 405 and BR 106 were obtained with densities of 61 and 70 thousand plants ha-1, respectively. In general, to produce marketable green ears, cultivar BR 106 was better in terms of number of ears, but the other cultivar was better in terms of ear weight. Cultivar AG 405 responds better to increased density for grain production.