Open Access Original Research Article

Path Analysis in Cowpea Reveals Protein Accumulation Dependency of Mineral Nutrients Accumulation

Francisco Cleilson Lopes Costa, Marlenildo Ferreira Melo, Ana Raquel de Oliveira Mano

Journal of Experimental Agriculture International, Page 1-10
DOI: 10.9734/jeai/2019/v32i530113

This work aimed at evaluating the effects of the nutrients on the protein content of cowpea grains. The trial was carried out in completely randomized design, in the Instituto Federal do Ceará (Federal Institute of Ceará), Limoeiro do Norte, Ceará State, Brazil, between October and November 2018. Grains of 10 cowpea cultivars were evaluated about its mineral nutrient phosphorus, potassium, calcium, magnesium, sulfur, chlorine, iron, zinc, copper, manganese, boron, sodium and protein contents. The seeds of the cultivars were obtained from the farmers market in three municipalities of the Ceará State, Brazil, in the crop year 2017. The components of variances within and between families were computed by analysis of variance, and the genetic variance and correlation were therefrom estimated. The statistical analyses of variance, Pearson’s correlation and Path analysis were carried out. The protein content broad sense heritability was 60.47%, and the other cowpea traits evaluated had high broad heritability values, ranging from 49.91% (sulfur content) to 99.69% (zinc content). No mineral nutrient content presented any genotype correlation with protein content, that is, no gene function is related to mineral nutrients and protein accumulation. Potassium (0.44), chlorine (0.38) and calcium (0.35) presented the higher path coefficients in protein of cowpea accumulation but are still weak indices (<0.50) to be indicated for screening. In screening cowpea cultivars for protein content, potassium and related traits are not the most important but present some degree of dependency with protein accumulation in the grains, resulting from path effects.

Open Access Original Research Article

The Role of Ethylene on Banana Fruit Ripening Via Sugar and Starch Metabolism

Sarah Nadja Araújo Fonseca, Willian Batista-Silva, Edson Hiydu Mizobutsi, Gláucia Michelle Cosme Silva, Juceliandy Mendes da Silva Pinheiro, Mariana Oliveira de Jesus, Gisele Polete Mizobutsi

Journal of Experimental Agriculture International, Page 1-12
DOI: 10.9734/jeai/2019/v32i530115

Banana as a climacteric fruit has a relatively short shelf-life period and thus, technologies that decrease the metabolism and the triggering of the maturation process are extremely necessary on its postharvest conservation. However, the consequences of these technologies on quality attributes are unknown. Therefore, we evaluate the effects of 1-Methylcyclopropene associated with low density polyethylene bags on physical and chemical attributes in the postharvest of banana fruits. Bananas were treated with different concentration of 1-Methylcyclopropene as 0, 50, 100, 150 and 200 ηL.L-1 under refrigeration and harvest in five different times after treatment. Further, fruits treated with 50 ŋL.L-¹ showed a more advanced stage of ripening after the 25 days of storage. Altogether, our results suggest 1-MCP is an effective treatment to control sugar and starch metabolism in banana and its efficiency is directly dependent of storage temperature. Additionally we identify interestingly correlation with skin color changes with sugars and starch content, which can indicate its potentiality of the fitted equations for prediction of central metabolism of bananas non-destructively using ‘hue angle and chrome’ value.

Open Access Original Research Article

Overcoming Dormancy and Influence of Light on the Physiological Quality of Senna cana (Fabaceae) Seeds

Jordânia X. Medeiros, Ana L. P. Feliciano, Valderez P. Matos, Girlânio H. Silva, Yana S. Lopes, Rinaldo L. C. Ferreira, Rejane R. C. Carvalho

Journal of Experimental Agriculture International, Page 1-9
DOI: 10.9734/jeai/2019/v32i530116

Environmental factors affect the germination process, like the presence of seed coat and the quality of light; these informations are still scarce for many native species from Brazil, especially for Senna cana, which there are no adequate standards and methodologies to be used in germination tests. The aim of this research was to recommend adequate pre-germinative treatment(s) to overcome seed dormancy, and determine the degree of influence of different light regimes in seed germination of S. cana. Two experiments were carried out: T1-evaluation of different methods of dormancy overcoming (intact seeds (control), T2-imbibition of the intact seeds for 24 hours (in distilled water), T3-scarified seeds with sandpaper n° 100 in the hilum opposite region, T4-scarified seeds with sandpaper n° 100 in the region the hilo opposite region and imbibition in water (in distilled water) for 24 hours; T5-imbibition in water at 80°C); 2-Influence of light quality on seed germination and vigor (white light, red light, far red light and absence of light). The evaluated parameters were: first germination count, percentage of germination, IVG (Germination speed index), MGT (Mean germination time). Treatments were compared by Tukey at 5% probability. The best method for overcoming seed dormancy was mechanical scarification with sandpaper nº 100. The germination of the seeds of S. cana can be classified as indifferent to the luminosity, despite germinative response be greater under white and red light.

Open Access Original Research Article

Evaluation of a Low-cost Camera for Agricultural Applications

Abdon Francisco Aureliano Netto, Rodrigo Nogueira Martins, Guilherme Silverio Aquino de Souza, Fernando Ferreira Lima dos Santos, Jorge Tadeu Fim Rosas

Journal of Experimental Agriculture International, Page 1-9
DOI: 10.9734/jeai/2019/v32i530117

This study aimed to modify a webcam by replacing its near-infrared (NIR) blocking filter to a low-cost red, green and blue (RGB) filter for obtaining NIR images and to evaluate its performance in two agricultural applications. First, the sensitivity of the webcam to differentiate normalized difference vegetation index (NDVI) levels through five nitrogen (N) doses applied to the Batatais grass (Paspalum notatum Flugge) was verified. Second, images from maize crops were processed using different vegetation indices, and thresholding methods with the aim of determining the best method for segmenting crop canopy from the soil. Results showed that the webcam sensor was capable of detecting the effect of N doses through different NDVI values at 7 and 21 days after N application. In the second application, the use of thresholding methods, such as Otsu, Manual, and Bayes when previously processed by vegetation indices showed satisfactory accuracy (up to 73.3%) in separating the crop canopy from the soil.

Open Access Original Research Article

Effect of Indolebutyric Acid Immersion Period on the Rhizogenic Process of Guava Cuttings (Psidium guajava L.) Cultivar Século XXI

Jussara Cristina Firmino da Costa, Rejane Maria Nunes Mendonça, Gerciane Cabral da Silva, Silvanda De Melo Silva, Walter Esfrain Pereira, Carlos Eduardo Magalhães dos Santos

Journal of Experimental Agriculture International, Page 1-7
DOI: 10.9734/jeai/2019/v32i530120

In the rhizogenic process, the immersion time of the base of the cuttings to be propagated in plant regulators depends on the concentration of the solutions, the cultivar to be used and the type of cutting required. Therefore, this research work has as objective to investigate which immersion time, in solution with indolebutyric acid promotes a greater rooting in herbaceous cuttings of guava cultivar Século XXI. The experiment was distributed in the completely randomized design, being defined as treatments the immersion times (5, 10, 15 and 20 seconds) of the base of the cuttings in the solution of indolebutyric acid - IBA at the concentration of 2000 mg L-1, with three replicates and 10 cuttings per plot. In relation the variable dry mass of the aerial part, this presents a favorable response to the different immersion times in indolebutyric acid. Diverging of the variables cuttings rooted, live without root, number of roots, root length, callus, sprout, leaf retention and mortality which were not influenced by the different immersion times of the base of the cuttings in the plant regulator. Concluding that the different times of immersion of the base of the cuttings do not influence in the rhizogenic process of herbaceous cuttings of guava cultivar Século XXI. For the variable dry mass of aerial part, the immersion time of 5 seconds in the concentration of 2000 mg L-1 in AIB, present the better results when compared to the other concentrations.