Jailton Garcia Ramos

Beet Crop under Different Fertilization and Nitrogen Fertigation in Protected Environment

Chemical fertilizers have been increasingly used in agriculture. The application of these nutrients via irrigation water has been evaluated in order to obtain productive results in agricultural yield. The objective of this research was to evaluate the effect of nitrogen (N) doses, applied by fertigation and associated with different types of basal fertilization, on the growth and production of beet. The experiment was conducted at the Federal University of Campina Grande (UFCG), in a protected environment belonging to the Academic Unit of Agricultural Engineering (UAEA). The adopted statistical design was completely randomized blocks, with three replicates, and the factors were arranged in a 5 × 3 factorial scheme, corresponding to five N doses (0, 50, 100, 150 and 200 mg dm-3 of soil), and three types basal fertilization (soil without fertilizer, earthworm humus, earthworm humus + NPK). At 45 days after transplanting, the number of leaves per plant, plant height, stem diameter, leaf area, green intensity, bulb diameter, stem length, bulb fresh weight, bulb dry weight and total soluble solids (°Brix) were quantified. Both Soil basal fertilization significantly influenced beet growth and production, and the treatment with earthworm humus and earthworm humus + NPK led to the best results for the analyzed variables. The highest N dose promoted the best performance for stem diameter and content of total soluble solids (°Brix).

ACÚMULO DE FITOMASSA DE CULTIVARES DE ALFACE HIDROPÔNICA SUBMETIDAS À SALINIDADE

O objetivo deste estudo foi avaliar os efeitos de diferentes niveis de salinidade na acumulacao de fitomassa de duas cultivares de alface sob cultivo hidroponico. O experimento foi realizado em um ambiente protegido na Universidade Federal de Campina Grande (UFCG), Campus I, durante o periodo 01 a 22 de setembro de 2016. O delineamento experimental foi inteiramente casualizado (DIC), em esquema fatorial 2x4, duas variedades de alface, Valentina (C1) e Alcione (C2) e quatro niveis de condutividade eletrica da solucao nutritiva (CESN) (1,6, 3,6, 5,6 e 7,6 dS m-1), totalizando 8 tratamentos com 3 repeticoes cada, resultando em 24 unidades experimentais. As variaveis analisadas foram o numero de folhas, fitomassa fresca e seca de folhas, caule e raizes, e fitomassa total da parte aerea. Observou-se que as variaveis fitomassa fresca das folhas e do caule, e fitomassa seca das folhas foram significativamente afetadas pelos niveis de salinidade, apenas a fitomassa seca das folhas e a fitomassa fresca das raizes diferiram entre as cultivares. O ponto de maxima producao de materia fresca das folhas foi observado na CESN de 3,5 dS m-1, o acumulo de fitomassa decresceu 31,48% para CESN de 7,6 dS m-1. Houve interacao entre os fatores apenas para a massa seca da folha.

Vigor and tolerance of cowpea (Vigna unguiculata) genotypes under salt stress

Saline stress is a frequent phenomenon in the arid and semi-arid regions of the globe, affecting the agricultural production of these regions, and it is necessary to use strategies that minimize the impacts of saline stress under agriculture. This requires the incorporation of species, variety and genotypes tolerant to increase agricultural production in those regions. This study aimed to evaluate germination and initial growth of cowpea genotypes under salt stress. The experimental design was completely randomized in 19 x 3 factorial scheme, composed of nineteen cowpea cultivars and three osmotic potentials, with four replicates of 50 seeds each. The germination test lasted for eight days, when the seeds were evaluated for germination percentage, germination speed index, length of shoot and root, accumulation of dry mass of shoot and root. The increase in salinity affected germination and initial growth of the cowpea genotypes. The genotypes 6 MNCO2-689F-2-8, 10 MNCO2-675F-4-10, 12 MNCO3-737F-5-9, 16 MNCO2-677F-2, 18 BRS-Pajeú and 19 – Paulistinha exhibited higher tolerance to salt stress in the stage of germination and initial growth. The genotypes 11 MNCO2-675F-9-5, 13 BRS-Tumucumaque, 15 MNCO3-736F-7 and 17 BR17-Gurgueia were more susceptible to the effects of salt stress in the stage of germination and initial growth.