Soil and foliar zinc biofortification of broccolini: effects on plant growth and mineral accumulation

© 2020 CSIRO. Millions of people have Zn-deficient diets, so Zn-biofortified crops could prevent such deficiency. The aim of this study was to evaluate the use of agronomic Zn biofortification of broccolini-a new hybrid crop variety derived from a cross between kalian cabbage and broccoli. Plants were grown in pots using a Zn deficient soil. Four fertiliser treatments were tested: (1) control (2) soil application of 5 mg ZnSO4•7H2O kg-1 soil (3) foliar application at the early flowering stage of 0.5% (w/v) ZnSO4•7H2O (4) combined soil and foliar treatments. Florets were harvested in four sequential harvests. There was a decrease in both growth and leaf composition of Zn, Ca, Fe and Mg. Soil Zn application increased floret production. There were increases in the Zn concentration stem+leaves and florets of 12- and 2.5-fold in foliar and soil+foliar treatments respectively. PA:Zn molar ratios decreased under both foliar and soil+foliar treatments. Boiling reduced Zn concentration by 40%, along with a decrease of other mineral nutrients. A soil+foliar treatment can increase both plant growth and Zn concentration in broccolini, and boiled 100 g portion of biofortified florets fertilised at rates in this study would deliver ∼49 mg Zn, a 46% increase than in the non-biofortified broccolini

Soil and foliar zinc application to biofortify broccoli (Brassica oleracea var. Italica L.): Effects on the zinc concentration and bioavailability

© 2020, Czech Academy of Agricultural Sciences. All rights reserved. Agronomic zinc (Zn) biofortification of crops could help to alleviate dietary Zn deficiency, which is likely to affect more than one billion people worldwide. To evaluate the efficiency of agronomic Zn biofortification of broc-coli, four application treatments were tested: no Zn application (control); soil application of 5 mg/kg ZnSO4·7 H2O (soil); two sprays (15 mL/pot each) of 0.25% (w/v) ZnSO4·7 H2O (foliar); and soil + foliar combination. Soil Zn application increased Zn-DTPA (diethylenetriamine pentaacetic acid) concentration by 3.7-times but did not affect plant growth or plant Zn concentration. Foliar Zn application increased stem + leaves and floret Zn concentration by 78 and 23 mg Zn/kg, respectively, with good bioavailability based on phytic acid concentration. Boiling decreased mineral concentration by 19%, but increased bioavailability by decreasing the phytic acid concentration. The entire broccoli could constitute a good nutritional source for animals and humans. An intake of 100 g boiled florets treated with the foliar treatment will cover about 36% of recommended dietary intake (RDI) of Zn, together with 30% of Ca, 94% of K, 32% of Mg, 6% of Na, 55% of P, 60% of S, 10% of Cu, 22% of Fe, 43% of Mn, and 35% of Se RDIs

Effects of Selenate Application on Growth, Nutrient Bioaccumulation, and Bioactive Compounds in Broccoli (Brassica oleracea var. italica L.)

The biofortification of edible crops with selenium (Se) is a common and effective strategy to address inadequate Se intake, which is suffered by millions of people worldwide. However, there is little information regarding the effects of this practice on crops belonging to the important Brassica family. To evaluate the efficacy of foliar Se application on broccoli, four treatments with varying Se concentrations were tested: 0%, 0.05%, 0.10%, and 0.15% (w/v), applied as sodium selenate during the early flowering stage. Although no overall effects on growth and biomass parameters were observed, the results indicate that the lowest Se dose (0.05-Se) was sufficient to notably increase Se concentration in the florets, even after boiling. Based on the increase to 14.2 mg Se kg−1 of dry matter in this broccoli fraction, it was estimated that consuming a 100-gram portion of boiled florets biofortified with 0.05% Se would provide approximately 140 µg of Se, which could be sufficient to potentially improve human selenium status, as previously documented. Moreover, the results obtained underscore how the application of this small dose was also adequate to reduce phytate concentration in the florets and to increase antioxidant and polyphenol concentrations, thereby improving the concentration and bioavailability of other essential nutrients, including Ca, Mg, Fe, and Zn, along with improving its quality as an antioxidant food

Effect of Processing on Some Quality Parameters of Flour and Bread Made from Wheat Grain Biofortified with Zn and Se

Millions of people have inadequate Se and Zn intakes, but agronomic biofortification could prevent this. This study evaluated the effect of the combined Zn and Se biofortification on the quality parameters of grain, and on the composition of minerals (Zn, Se, Mg, Ca and Fe) and their availability in bread-making wheat (Triticum aestivum L.) products, white flour, wholemeal bread and white bread were evaluated. The studied treatments were soil Zn (no Zn, and 50 kg Zn ha−1) and foliar applications (0, 10 g Se ha−1, 8 kg Zn ha−1, and 10 g Se ha−1 + 8 kg Zn ha−1) and were tested in a two-year field experiment (2017–2018, 2018–2019). The foliar combined biofortification increased the concentration of both minerals in white flour, wholemeal bread and white bread by about 33%, 24% and 51%, respectively for Zn, and 3.3-fold, 3.4-fold and 2.7-fold for Se, showing a synergistic effect on Se concentration with the Se and Zn combination. While the loss of Zn and Se during the milling process was41% and 18%, respectively, baking caused a loss of 15% and 19%, respectively, for wholemeal bread, and up to 61% and 29% for Zn and Se for white bread. Hence, although the consumption of wholemeal bread instead of white bread may enhance Zn and Se intake more than biofortification, until consumption habits change, the biofortification of wheat can help to mitigate inadequate Zn and Se intakes in the general population

Students´ Perception of Real-Time Quiz Kahoot! As a Review Tool in Higher Education: A Case of Study

The use of gamification has spread in recent years, proving to be an effective tool to increase student motivation. Among them stands out Kahoot!, an online questionnaire in which students compete among themselves by counting both the number of correct answers and the response speed. Its effectiveness has been tested mainly in primary and secondary students, with much less available information at higher levels. This study evaluates the opinion of 48 students in Plant Science, a subject of 2nd course of Agricultural Engineering Grade, after carrying out three Kahoot! questionnaires with 12 questions with a single-answer, with two weeks between one and the next. To evaluate the contents fixation a reunified quiz was done, one week after the last Kahoot!, chosen randomly five questions from each questionnaire. The satisfaction of more than 90% of the students was positive or very positive, mainly because of creating a more positive and participatory learning environment. The use as a scoring tool produces a decrease in the acceptance in some students, producing anxiety in 25% of the students, due to the limited available time in about 27% of students. Furthermore Kahoot! has been found as a efficient tool for consolidating knowledge, as the number of questions that the students have consolidated is greater than 20% in the three questionnaires carried out, regardless of whether the period elapsed was 5, 3 or 1 week

Foliar zinc biofortification effects in <i>Lolium rigidum</i> and <i>Trifolium subterraneum</i> grown in cadmium-contaminated soil

<div><p>Zinc (Zn) is an important micronutrient that can alleviate cadmium (Cd) toxicity to plants and limit Cd entry into the food chain. However, little is known about the Zn-Cd interactions in pasture plants. We characterized the effects of foliar Zn application and Cd uptake by ryegrass (<i>Lolium rigidum</i> L.) and clover (<i>Trifolium subterraneum</i> L.) grown on Cd-contaminated soils; all combinations of foliar Zn applications (0, 0.25 and 0.5% (w/v) ZnSO₄·7H₂O) and soil Cd concentrations (0, 2.5 and 5 mg Cd kg^-1) were tested. For both plant species, soil concentrations of DTPA-extractable Cd and Zn increased with an increase in the Cd and Zn treatments, respectively. Compared with <i>L</i>. <i>rigidum</i>, <i>T</i>. <i>subterraneum</i> accumulated, respectively, 3.3- and 4.1-fold more Cd in the 2.5-Cd and 5-Cd treatments and about 1.3-, 2.3- and 2.8-fold more Zn in the No-Zn, 0.25-Zn and 0.5-Zn treatments. Also, DTPA-Zn concentration was higher in soil after <i>T</i>. <i>subterraneum</i> than <i>L</i>. <i>rigidum</i> growth regardless of Zn applications. Foliar application of 0.25% (w/v) Zn significantly decreased the total Cd concentration in shoots of both species grown in the Cd-contaminated soil and ameliorated the adverse effects of Cd exposure on root growth, particularly in <i>T</i>. <i>subterraneum</i>.</p></div

DTPA-extractable soil Cd and shoot Cd concentration in <i>L</i>. <i>rigidum</i>, and root DW, root length, shoot Cd concentration and phytate:Zn molar ratio in <i>T</i>. <i>subterraneum</i> as affected by the interaction between the soil Cd and Zn foliar treatments.

<p>Mean ± standard error.</p

Combined Selenium and Zinc Biofortification of Bread-Making Wheat under Mediterranean Conditions

Millions of people worldwide have an inadequate intake of selenium (Se) and zinc (Zn), and agronomic biofortification may minimise these problems. To evaluate the efficacy of combined foliar Se and Zn fertilisation in bread making wheat (Triticum aestivum L.), a two-year field experiment was established in southern Spain under semi-arid Mediterranean conditions, by following a split-split-plot design. The study year (2017/2018, 2018/2019) was considered as the main-plot factor, soil Zn application (50 kg Zn ha−1, nor Zn) as a subplot factor and foliar application (nor Se, 10 g Se ha−1, 8 kg Zn ha−1, 10 g Se ha−1 + 8 kg Zn ha−1) as a sub-subplot factor. The best treatment to increase both Zn and Se concentration in both straw, 12.3- and 2.7-fold respectively, and grain, 1.3- and 4.3-fold respectively, was the combined foliar application of Zn and Se. This combined Zn and Se application also increased on average the yield of grain, main product of this crop, by almost 7%. Therefore, bread-making wheat seems to be a very suitable crop to be used in biofortification programs with Zn and Se to alleviate their deficiency in both, people when using its grain and livestock when using its straw

DTPA-extractable soil Zn, root length, shoot dry weight (DW), and shoot Zn concentration and phytate:Zn molar ratio in <i>L</i>. <i>rigidum</i>, and DTPA-extractable soil Cd and Zn, average root diameter, shoot DW, and shoot Zn and protein concentration in <i>T</i>. <i>subterraneum</i> as affected by the foliar Zn treatment.

<p>Mean ± standard error.</p

Root length and shoot phytate:Zn molar ratio in <i>L</i>. <i>rigidum</i>, and DTPA-extractable soil Cd and shoot DW in <i>T</i>. <i>subterraneum</i> as affected by the soil Cd treatment. Mean ± standard error.

<p>Root length and shoot phytate:Zn molar ratio in <i>L</i>. <i>rigidum</i>, and DTPA-extractable soil Cd and shoot DW in <i>T</i>. <i>subterraneum</i> as affected by the soil Cd treatment. Mean ± standard error.</p