Um experimento foi conduzido entre março e junho de 2012 no Centro de Ciências Agrárias da UFPB, Areia, PB, para avaliar o crescimento inicial de plantas de oiticica (Licania rigida Benth), pela altura, diâmetro caulinar, área foliar, teor de clorofila total, biomassa das raízes e da parte aérea de plantas em função da salinidade da água, biofertilizante bovino e potássio no solo. Os tratamentos foram arranjados em delineamento inteiramente casualizado, com seis repetições, em esquema fatorial 5 x 2 x 2, correspondendo a cinco águas com condutividade elétrica de 0,5; 1,5; 3,0; 4,5 e 6,0 dS m-1, dois tratamentos sem e com 300 mL de biofertilizante bovino aplicado de uma só vez no solo e dois tratamentos sem e com 1,4 g de cloreto de potássio. O aumento da salinidade das águas inibiu o crescimento e a qualidade das mudas mas com maiores perdas nas plantas dos tratamentos sem biofertilizante e sem cloreto de potássio. As plantas cultivadas no solo com cloreto de potássio cresceram mais que as do solo sem o fertilizante mineral.

Lima bean (Phaseolus lunatus) can be considered as an alternative income and food supply to farmers of the Brazilian Northeast. This crop has faced serious sanitary problems. Among the most important diseases that attack this crop, the anthracnose caused by Colletotrichum truncatum requires greater attention. This study aimed to determine the resistance of lima bean accessions to the isolates of C. truncatum. Detached leaves were used from ten lima bean accessions, originated from production fields in Paraíba State - Brazil. They were artificially inoculated with ten isolates of C. truncatum. The isolates were grown on bean-dextroseagar medium under temperature 27 ± 2 °C and a photoperiod of 12 hours, for fourteen days. The evaluations of the accessions’ resistance to the isolates were performed at 5, 7, 9, 11 and 13 days after inoculation (DAI), adopting a scale of notes, and the results were transformed in the area under the disease progress curve. The research was carried out in completely randomized design, in a 10x10 factorial arrangement (accessions x isolates) with 12 replications. The first symptoms of anthracnose on the detached leaves appeared from the third day after inoculation. The accessions were grouped from highly to moderately resistant or susceptive. The aggressiveness among C. truncatum isolates varied depending on the genetic variability of the lima bean accessions used. Accessions with significant resistance levels to anthracnose can be used as resistance sources in future breeding programs.

Salinity can have detrimental effects on plant development. To minimize this damage, strategies such as balanced maintenance of plants’ nutritional status have been proposed previously. The objective of this study is to investigate whether the optimization of foliar nitrogen fertilization can promote the growth and photochemical efficiency of purple basil subjected to salt stress. The experiment was performed using a randomized block design with an incomplete 5 × 5 factorial arrangement generated through experimental matrix Central Composite Design with two parameters: salinity of irrigation water at 0.5, 0.81, 2.75, 4.69, and 5.50 dS m-1; and nitrogen doses at 0, 58.58, 200, 341.42, and 400 mg L-1. It was found that an increase in the salinity of irrigation water reduced the growth and photochemical efficiency of purple basil. However, the foliar application of nitrogen at the concentration of 400 mg L-1 attenuated the harmful effects of salinity on both the absolute and relative growth rates of stem diameter, the relative growth of plant height, and chlorophyll A fluorescence. These results showed that foliar nitrogen fertilization is a suitable strategy to help mitigate salt stress in basil plants.

The use of seeds with good sanitary and physiological potential ensures the establishment of the crop, with a uniform, vigorous and disease-free seedling stand, which will result in good productivity levels. Seen that, the objective was to evaluate the sanitary and physiological quality of purple corn seeds (Zea mays L.) submitted to thermotherapy. They were subjected to heat treatment with immersion in sterile distilled water (SDW) heated at 50, 60 and 70 °C for 1, 2, and 3 minutes. The control (0 min) correspondens only to immersing the seeds in SDW, which were submitted to sanitary and germination tests in a completely randomized experimental design, in a factorial arrangement 3 × 3 + 1 (exposure time × temperature + additional control). Data were subjected to analysis of variance, and the means were compared with the Scott-Knott test up to 5% of probability, with the aid of the statistical program SISVAR^®. Immersing Zea mays seeds in hot water at 50, 60 and 70 °C for 1, 2, and 3 minutes is efficient to prevent the increased incidence of Aspergillus sp., Penicillium sp., and Fusarium sp. The heat treatment at 60 °C for 1 and 2 minutes of immersion reduces the incidence of fungal mycoflora without impairing the physiological quality of seeds.

Basil (Ocimum basilicum L.), a medicinal and aromatic plant extensively cultivated in the Northeast region of Brazil, encounters growth challenges attributed to the salinity of irrigation water and soil. Nitrogen (N) is a crucial macronutrient employed to mitigate salt stress in plants. Therefore, this study aimed to evaluate the production of phytomass and chlorophyll synthesis in purple basil plants grown under salinity stress and nitrogen fertilization. The experiment was conducted in 2021 under protected environmental conditions at the Center for Agricultural Sciences, Universidade Federal Paraíba, Areia-PB, Brazil. Five levels of salt stress (0.0, 0.80, 2.75, 4.70, and 5.50 dS m-1) and five doses of N (0.00, 58.58, 200.00, 341.42, and 400.00 mg L-1) applied via foliar were studied. The results revealed that foliar fertilization with N increases plant tolerance to salt stress, promoting root fresh and dry mass accumulation at 294.96 and 205.36 mg L-1 and under ECw of 1.14 and 0.5 dS m-1, respectively. Applying 217.39 and 231.30 mg L-1 of N improves the production of stem dry biomass and the shoot/root ratio of basil plants subjected to salinity of 0.5 dS m-1. The electrical conductivity of irrigation water above 0.8 dS m-1 adversely affects biomass production. The salinity at 3.8 to 4.0 dS m-1 stimulated chlorophyll synthesis in purple basil plants. However, the foliar application of N proves to be a strategic approach to counteract these effects, resulting in increased total dry mass production and chlorophyll contents.