A Seaweed Extract-Based Biostimulant Mitigates Drought Stress in Sugarcane.

Drought is one of the most important abiotic stresses responsible for reduced crop yields. Drought stress induces morphological and physiological changes in plants and severely impacts plant metabolism due to cellular oxidative stress, even in C4 crops, such as sugarcane. Seaweed extract-based biostimulants can mitigate negative plant responses caused by drought stress. However, the effects of foliar application of such biostimulants on sugarcane exposed to drought stress, particularly on plant metabolism, stalk and sugar yields, juice purity, and sugarcane technological quality, have received little attention. Accordingly, this study aimed to evaluate the effects of foliar application of a seaweed extract-based biostimulant on late-harvest sugarcane during the driest period of the year. Three experiments were implemented in commercial sugarcane fields in Brazil in the 2018 (site 1), 2019 (site 2), and 2020 (site 3) harvest seasons. The treatments consisted of the application and no application of seaweed extract (SWE) as a foliar biostimulant in June (sites 2 and 3) or July (site 1). The treatments were applied to the fourth ratoon of sugarcane variety RB855536 at site 1 and the fifth and third ratoons of sugarcane variety SP803290 at sites 2 and 3, respectively. SWE was applied at a dose of 500 ml a.i. ha-1 in a water volume of 100 L ha-1. SWE mitigated the negative effects of drought stress and increased stalk yield per hectare by up to 3.08 Mg ha-1. In addition, SWE increased stalk sucrose accumulation, resulting in an increase in sugar yield of 3.4 kg Mg-1 per hectare and higher industrial quality of the raw material. In SWE-treated plants, Trolox-equivalent antioxidant capacity and antioxidant enzyme activity increased, while malondialdehyde (MDA) levels decreased. Leaf analysis showed that SWE application efficiently improved metabolic activity, as evidenced by a decrease in carbohydrate reserve levels in leaves and an increase in total sugars. By positively stabilizing the plant's cellular redox balance, SWE increased biomass production, resulting in an increase in energy generation. Thus, foliar SWE application can alleviate drought stress while enhancing sugarcane development, stalk yield, sugar production, and plant physiological and enzymatic processes.

Inhibition of the lemon brown rot causal agent Phytophthora citrophthora by low-toxicity compounds.

BACKGROUND: Phytophthora spp., soil-borne oomycetes, cause brown rot (BR) on postharvest lemons. The management of this disease is based on cultural practices and chemical control using inorganic salts of limited efficacy. In the search for new alternatives, the aim of this work was to evaluate the effect of low-toxicity compounds to inhibit the growth of P. citrophthora and to control BR disease on lemons. Sodium bicarbonate, potassium sorbate, polyhexamethylene guanidine, Ascophyllum nodosum extract and a formulation containing phosphite salts plus A. nodosum (P+An) were evaluated. RESULTS: All tested products inhibited mycelial growth, sporangia formation and zoospore germination of P. citrophthora in vitro. In postharvest applications on artificially inoculated lemons, only P+An exhibited a BR curative effect, with incidence reduction of around 60%. When this formulation was applied in field treatments, BR incidence was reduced by 40% on lemons harvested and inoculated up to 30 days post application. CONCLUSION: Our results demonstrate the in vitro direct anti-oomycete effect of low-toxicity compounds and the in vivo efficacy of P+An formulation to control BR, encouraging the incorporation of the latter in the management of citrus BR. © 2020 Society of Chemical Industry.

Extrato de algas como bioestimulante na nutrição e produtividade do trigo irrigado na região de Cerrado / Algae extract as biostimulant in nutrition and irrigated wheat yield in the cerrado region

Produtos que apresentam ação bioestimulante em culturas agrícolas, como a base da alga Ascophyllum nodosum, vêm sendo utilizado pelo seu efeito hormonal benéfico na nutrição e crescimento das plantas, com o intuito de se aumentar a produtividade de grãos. Diante do exposto, objetivou-se avaliar o efeito bioestimulante e fertilizante da alga Ascophyllum nodosum no índice de clorofila foliar, concentração de nutrientes no tecido foliar, componentes produtivos e produtividade de grãos de trigo irrigado em região de Cerrado. A pesquisa foi desenvolvida em Selvíria –MS, em um Latossolo Vermelho Distrófico. O delineamento experimental foi em blocos ao acaso com cinco tratamentos e cinco repetições, sendo os tratamentos: Testemunha, aplicação única (aos 24 dias após emergência (d.a.e.) do trigo) ou dupla (aos 24 e 60 d.a.e) de extrato de Ascophyllum nodosum com o produto comercial polifértil®, e aplicação única (aos 24 d.a.e) ou dupla (aos 24 e 60 d.a.e) de extrato de Ascophyllum nodosum com o produto Acadian®. A nutrição das plantas de trigo irrigado foi pouco influenciada pelos extratos de alga à base de Ascophyllum nodosum, sendo constatado maior ICF e concentrações foliar de S e Mn em relação à testemunha, quando estes bioestimulantes foram aplicados. Os extratos de alga à base de Ascophyllum nodosum não influenciaram os componentes produtivos e produtividade de grãos de trigo, portanto sua utilização como bioestimulante não é necessária em solos com fertilidade adequada e cultivo irrigado.

Products which have biostimulant action on agricultural crops, such as the base of the Ascophyllum nodosum algae, have been used for its beneficial hormonal effect on nutrition and growth of plants, in order to increase grain yield. Thus, it was aimed to evaluate the effect biostimulant and fertilizer of Ascophyllum nodosum algae in the production components and grains yield of irrigated wheat in the Cerrado region. The research was developed in Selvíria - MS, on an Oxisol. The experimental design was randomized blocks with five treatments and five repetitions, being the treatments: control, only one application (at 24 days after emergence (dae) of wheat) or double (to 24 and 60 dae) of Ascophyllum nodosum extract with polifértil® the commercial product, and only one application (at 24 dae) or double (at 24 and 60 dae) from Ascophyllum nodosum extract with Acadian® product. The plants nutrition of irrigated wheat was slightly influenced by algae extracts based on Ascophyllum nodosum, provided greater LCI and leaf concentrations of S and Mn compared to control, when these biostimulants were applied. The algae extracts with Ascophyllum nodosum did not influence the production components and yield of wheat, therefore their use as biostimulant is not required in soils with adequate fertility andirrigated cultivation.

Extrato de algas como bioestimulante na nutrição e produtividade do trigo irrigado na região de Cerrado / Algae extract as biostimulant in nutrition and irrigated wheat yield in the cerrado region

Produtos que apresentam ação bioestimulante em culturas agrícolas, como a base da alga Ascophyllum nodosum, vêm sendo utilizado pelo seu efeito hormonal benéfico na nutrição e crescimento das plantas, com o intuito de se aumentar a produtividade de grãos. Diante do exposto, objetivou-se avaliar o efeito bioestimulante e fertilizante da alga Ascophyllum nodosum no índice de clorofila foliar, concentração de nutrientes no tecido foliar, componentes produtivos e produtividade de grãos de trigo irrigado em região de Cerrado. A pesquisa foi desenvolvida em Selvíria –MS, em um Latossolo Vermelho Distrófico. O delineamento experimental foi em blocos ao acaso com cinco tratamentos e cinco repetições, sendo os tratamentos: Testemunha, aplicação única (aos 24 dias após emergência (d.a.e.) do trigo) ou dupla (aos 24 e 60 d.a.e) de extrato de Ascophyllum nodosum com o produto comercial polifértil®, e aplicação única (aos 24 d.a.e) ou dupla (aos 24 e 60 d.a.e) de extrato de Ascophyllum nodosum com o produto Acadian®. A nutrição das plantas de trigo irrigado foi pouco influenciada pelos extratos de alga à base de Ascophyllum nodosum, sendo constatado maior ICF e concentrações foliar de S e Mn em relação à testemunha, quando estes bioestimulantes foram aplicados. Os extratos de alga à base de Ascophyllum nodosum não influenciaram os componentes produtivos e produtividade de grãos de trigo, portanto sua utilização como bioestimulante não é necessária em solos com fertilidade adequada e cultivo irrigado.(AU)

Products which have biostimulant action on agricultural crops, such as the base of the Ascophyllum nodosum algae, have been used for its beneficial hormonal effect on nutrition and growth of plants, in order to increase grain yield. Thus, it was aimed to evaluate the effect biostimulant and fertilizer of Ascophyllum nodosum algae in the production components and grains yield of irrigated wheat in the Cerrado region. The research was developed in Selvíria - MS, on an Oxisol. The experimental design was randomized blocks with five treatments and five repetitions, being the treatments: control, only one application (at 24 days after emergence (dae) of wheat) or double (to 24 and 60 dae) of Ascophyllum nodosum extract with polifértil® the commercial product, and only one application (at 24 dae) or double (at 24 and 60 dae) from Ascophyllum nodosum extract with Acadian® product. The plants nutrition of irrigated wheat was slightly influenced by algae extracts based on Ascophyllum nodosum, provided greater LCI and leaf concentrations of S and Mn compared to control, when these biostimulants were applied. The algae extracts with Ascophyllum nodosum did not influence the production components and yield of wheat, therefore their use as biostimulant is not required in soils with adequate fertility andirrigated cultivation.(AU)

Foliar application of microbial and plant based biostimulants increases growth and potassium uptake in almond (Prunus dulcis [Mill.] D. A. Webb).

The use of biostimulants has become a common practice in agriculture. However, there is little peer-reviewed research on this topic. In this study we tested, under controlled and replicated conditions, the effect of one biostimulant derived from seaweed extraction (Bio-1) and another biostimulant derived from microbial fermentation (Bio-2). This experiment utilized 2-years-old almond plants over two growing seasons in a randomized complete design with a full 2 × 4 factorial structure with two soil potassium treatments (125 µg g(-1) of K vs. 5 µg g(-1)) and four foliar treatments (No spray, Foliar-K, Bio-1, Bio-2). Rubidium was utilized as a surrogate for short-term potassium uptake and plant growth, nutrient concentration, and final plant biomass were evaluated. There was a substantial positive effect of both biostimulant treatments on total shoot leaf area, and significant increases in shoot length and biomass under adequate soil potassium supply with a positive effect of Bio-1 only under low K supply. Rubidium uptake was increased by Bio-1 application an effect that was greater under the low soil K treatment. Though significant beneficial effects of the biostimulants used on plant growth were observed, it is not possible to determine the mode of action of these materials. The results presented here illustrate the promise and complexity of research involving biostimulants.

Ascophyllum nodosum in the diet of tilapia (Oreochromis niloticus) and its effect after inoculation of Aeromonas hydrophila / Ascophyllum nodosum na dieta de tilapia (Oreochromis niloticus)e o efeito dela depois da inoculação com Aeromonas hydrophila

The objective of this study was to evaluate the effect of Ascophyllum nodosum brown seaweed meal (FAM) on the health of Nile tilapia submitted to inoculation with Aeromonas hydrophila. The experiment was conducted for a period of 40 days using 120 Nile tilapia fingerlings, with age of 40 days, distributed in 20 tanks. A diet including Ascophyllum nodosum seaweed meal at 20g.kg-1 and a control diet (without FAM) were provided which constituted the treatments. Thirty days after beginning the experiment, A. hydrophila was inoculated by bacterial inoculum diluted in sterile saline solution at a concentration of 10(6) CFU ml-1. Except for the width, which was greater for the treatment with the provision of FAM (P<0.05), there was no influence on the performance parameters of the fingerlings, but the occurrence of lesions in animals inoculated with A. hydrophila and fed with FAM was lower and they also exhibited a decline in the lesions in a shorter period of time than the control group. FAM prevents hepatopancreatic congestion in infected animals. Ascophyllum nodosum brown seaweed meal reduced the number of lesions in fish in a shorter time when compared to the control group.

O objetivo desse estudo foi avaliar o efeito da farinha de alga marinha marrom Ascophyllum nodosum (FAM) em alevinois de tilápias do Nilo sob desafio sanitário com inoculação de Aeromonas hydrophila. O experimento foi realizado durante um período de 40 dias com a utilização de 120 alevinos de tilápia do Nilo, distribuídos em 20 aquários. Foi fornecida uma ração com inclusão da farinha da alga marinha Ascophyllum nodosum a 20g.kg ração-1 e uma ração testemunha (sem FAM), que constituiram os tratamentos. Após 30 dias experimentais foi realizada a inoculação de Aeromonas hydrophila por meio de um preparado de inóculo bacteriano com diluição em solução salina estéril a concentração de 106 UFC/ml. Exceto para a largura, que foi maior para o tratamento com o fornecimento da FAM (P<0,05), não houve influência sobre parâmetros de desempenho dos alevinos, mas a ocorrência de lesões nos animais inoculados com A. hydrophila e alimentados com FAM foi menor e, eles também exibiram um declínio das lesões em um menor período de tempo em relação ao grupo controle. FAM impediu a congestão hepatopancreática em animais infectados. A farinha de alga marinha marrom Ascophyllum nodosum reduziu o número de lesões nos peixes em menor tempo quando comparado ao controle.

Ascophyllum nodosum in the diet of tilapia (Oreochromis niloticus) and its effect after inoculation of Aeromonas hydrophila / Ascophyllum nodosum na dieta de tilapia (Oreochromis niloticus)e o efeito dela depois da inoculação com Aeromonas hydrophila

The objective of this study was to evaluate the effect of Ascophyllum nodosum brown seaweed meal (FAM) on the health of Nile tilapia submitted to inoculation with Aeromonas hydrophila. The experiment was conducted for a period of 40 days using 120 Nile tilapia fingerlings, with age of 40 days, distributed in 20 tanks. A diet including Ascophyllum nodosum seaweed meal at 20g.kg-1 and a control diet (without FAM) were provided which constituted the treatments. Thirty days after beginning the experiment, A. hydrophila was inoculated by bacterial inoculum diluted in sterile saline solution at a concentration of 10(6) CFU ml-1. Except for the width, which was greater for the treatment with the provision of FAM (P<0.05), there was no influence on the performance parameters of the fingerlings, but the occurrence of lesions in animals inoculated with A. hydrophila and fed with FAM was lower and they also exhibited a decline in the lesions in a shorter period of time than the control group. FAM prevents hepatopancreatic congestion in infected animals. Ascophyllum nodosum brown seaweed meal reduced the number of lesions in fish in a shorter time when compared to the control group.(AU)

O objetivo desse estudo foi avaliar o efeito da farinha de alga marinha marrom Ascophyllum nodosum (FAM) em alevinois de tilápias do Nilo sob desafio sanitário com inoculação de Aeromonas hydrophila. O experimento foi realizado durante um período de 40 dias com a utilização de 120 alevinos de tilápia do Nilo, distribuídos em 20 aquários. Foi fornecida uma ração com inclusão da farinha da alga marinha Ascophyllum nodosum a 20g.kg ração-1 e uma ração testemunha (sem FAM), que constituiram os tratamentos. Após 30 dias experimentais foi realizada a inoculação de Aeromonas hydrophila por meio de um preparado de inóculo bacteriano com diluição em solução salina estéril a concentração de 106 UFC/ml. Exceto para a largura, que foi maior para o tratamento com o fornecimento da FAM (P<0,05), não houve influência sobre parâmetros de desempenho dos alevinos, mas a ocorrência de lesões nos animais inoculados com A. hydrophila e alimentados com FAM foi menor e, eles também exibiram um declínio das lesões em um menor período de tempo em relação ao grupo controle. FAM impediu a congestão hepatopancreática em animais infectados. A farinha de alga marinha marrom Ascophyllum nodosum reduziu o número de lesões nos peixes em menor tempo quando comparado ao controle.(AU)