In Brazilian agriculture there are few reports on trinexapac-ethyl (TE) effects on maize plant lodging management. This study aimed to evaluate the effects of sequential application of TE sprayed on different plant growth stages of maize using the simple hybrid P30F53HR and the variety SCS 154 Fortuna. Experiments were carried out in a greenhouse in the 2013 and 2014 harvests. Plants were grown singly in 5L pots filled with 75% soil and 25% substrate. The experimental design was a randomized complete block with four replications. The following treatments were performed: (T1) control (no application of growth retardant); (T2) application at V2 (100 g a.i. ha-1); (T3) sequential application of 100 g a.i. ha-1 at V2 plus V3; (T4) sequential application of 100 g a.i. ha-1 at V2+V3+V4; (T5) single application of 300 g a.i. ha-1 at V4; (T6) sequential application of 100 g a.i. ha-1 at V2+V3+V4+V5; (T7) sequential application of 100 g a.i. ha-1 at V2+V3+V4+V5+V6 and (T8) sequential application of 100 g a.i. ha-1 at V2+V3+V4+V5+V6+V7. The some morphological characteristics of the two maize genotypes changed in response to TE treatment. From stage V4 onwards, maize plant height showed signs of sensitivity to the growth retardant. Plants in T8 (TE applied over V2 to V7) were more sensitive to TE with over 45% reduction in plant height compared with application T7 (applied from V2 to V6). This response was similar in both maize genotypes, thus indicating that plants are highly sensitive to TE after the V6 stage.

About 1 billion people are currently suffering from chronic hunger, malnutrition, and vitamin A deficiency, while it is predicted that world food production needs to increase by 70% by 2050 to satisfy 9.9 billion predicted population in the world, relying on a natural resource base that is reaching its limits and with climate change adding further pressures on agriculture and acting as the main driver of crop diversity loss. The main goal of this chapter was to discuss the role of neglected crops (arrowroot, cassava, and cowpea) as potential sources of vitamin A with case studies of Mozambique country where the current population (30.5 million-mid-2018) is predicted to more than double by mid-2050 (67.4 million) while vitamin A deficiency and food insecurity are serious issues. Crops have an important role in rural communities and are nutrient dense and can be used in diet diversification and vitamin A alleviation. They are highly adapted to agroecological niches and marginal areas. The current research reinforces that neglected crops are potential sources of vitamin A with an extra extensive phytochemical composition that together are important in alleviating vitamin A deficiency. Their production promotion must be reinforced and incorporated in crop diversification.

A utilização de adubação como o uso de fertilizantes biológicos à base de microrganismos benéficos ao solo e à planta e de complexo de nutrientes é prática que tem como intuito promover melhorias no rendimento das culturas. O objetivo deste estudo foi avaliar a qualidade fisiológica de sementes de milho produzidas em diferentes preparos do solo com o uso de adubação biológica e bioestimulante via tratamento de semente. O experimento a campo foi conduzido na safra agrícola de 2015/2016, com sementes de milho híbrido AS1656 PRO2 (AGROESTE®). O delineamento experimental foi feito em blocos completos ao acaso, com cinco repetições. Os tratamentos foram: preparos do solo (plantio direto, escarificação e escarificação + plantio direto) e tratamento de sementes com a adubação biológica/bioestimulante (Bacsol®, Orgasol® e Bacsol® + Orgasol®). As variáveis estudadas foram: peso de mil sementes, germinação, comprimento de raiz, teste de frio, massa seca da parte aérea e de raiz de plântulas. Foram realizadas análise de variância (teste F) e comparação entre as médias e interações através do teste de Tukey 5% de significância. As sementes de milho produzidas com a aplicação da adubação biológica e o bioestimulante não incrementam a germinação e o vigor de sementes de milho do híbrido AS1656 PRO2, independentemente do sistema de preparo do solo.

Defoliation may interfere in the sink-source relationship and influence grain production and the respective technological quality of wheat flour, particularly in cultivars with potential as forage and in subsequent grain production. This study aimed to determine the effects of plant cutting heights and number of cuttings on the technological wheat flour quality of BRS Umbu and BRS Tarumã cultivars. A completely randomized design with four repetitions was used and treatments consisted of a combination of cutting heights (20 and 30 cm) and number of cuttings (no cutting, 1, 2 and 3 cuttings), resulting in the following treatments: 20/1, 20/2, 20/3 30/1, 30/2, 30/3 and controls with no cuttings. Hectoliter weight, grain crude protein, tenacity: extensibility ratio, gluten strength, falling number and wet gluten were measured. Regardless of the cutting height used, and after defoliation, the variables exhibited higher values than in non-defoliated plants, with protein content increasing by 6 and 11.3% for the BRS Tarumã and BRS Umbu cultivars, respectively. As such, it can be inferred that defoliation does not negatively affect the technological quality of wheat flour grown in a dual-purpose system.

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