Cassava roots yield and soil chemical and physical properties according to chicken manure fertilization

The cassava crop extracts large amounts of nutrients from the soil and, as a result, nutrients in adequate amounts in the soil favor its yield. Thus, this study aimed at evaluating the influence of laying chicken manure on cassava roots yield and morphological characteristics, as well as on soil chemical and physical properties. The experimental design was randomized blocks, with six replications, and treatments consisted of laying chicken manure doses (0 t ha-1, 6 t ha-1, 12 t ha-1 and 18 t ha-1) incorporated into the soil. It was observed that the crop reacted to the soil fertilization by increasing its yield per area and plant unit. Roots individual fresh matter, diameter and length remained constant with treatments. The soil pH and organic matter were raised with the addition of manure. Concerning soil nutrients, there was an increase in the P, Ca and Mg contents. The soil bulk density decreased, while the total soil porosity increased proportionally to the addition of manure. The addition of chicken manure up to 18 t ha-1 provided a higher cassava yield, due to an increase in the number of roots per plant and improvements in the soil chemical and physical properties

Fertilizer use and permanence time of sweet potato plantlets produced in trays

O objetivo deste trabalho foi avaliar a produção de mudas de batata-doce em bandejas de poliestireno, com utilização de fertilizante de liberação lenta, e estabelecer o tempo adequado de permanência dessas mudas nas bandejas. Utilizou-se o delineamento experimental inteiramente casualizado, em arranjo fatorial 5x5, com cinco doses do fertilizante de liberação lenta osmocote NPK 15-09-12 (0, 50, 100, 150 e 200 g por 25 kg de substrato) e cinco tempos de permanência nas bandejas (14, 28, 42, 56 e 70 dias após o plantio, DAP). Foram avaliados o número de raízes e de folhas e suas respectivas massas de matéria seca. Além disso, avaliou-se a integridade dos torrões em função do tempo de permanência das mudas nas bandejas, em experimento sem adição de fertilizante. Observou-se interação significativa entre doses do fertilizante e o tempo de permanência nas bandejas. A adubação com 150 g favoreceu o incremento do número de raízes e folhas e a massa de matéria seca das mudas, a partir de 14 DAP. Em geral, a integridade dos torrões aumenta com o tempo de permanência. Observaram-se sintomas de deficiência nutricional a partir dos 25 DAP, quando não foi utilizado fertilizante. O período de permanência em bandejas pode ser ampliado se o fertilizante de liberação lenta for utilizado.The objective of this work was to evaluate the production of sweet potato plantlets in polystyrene foam trays, using slow-release fertilizer and to establish the proper permanence time for this plantlets to stay in trays. An entirely radonmized experimental design was used with 5x5 factorial arrangement, with five doses of osmocote slow-release fertilizer NPK 15-09-12 (0, 50, 100, 150 e 200 g per 25 kg of the substrate) and five permanence times in the trays (14, 28, 42, 56 e 70 days after planting, DAP). The number of roots and leaves, and their respective dry matter mass were evaluated. Furthermore, clod integrity as a function of the permanence time of cuttings in trays was evaluated in an experiment without the use of fertilizers. It was observed significant interaction between fertilizer doses and permanence time in the trays. The fertilization with 150 g increased the number of roots and leaves and the dry matter of new plantlets, after 14 DAP. Generally, clod integrity increases with permanence time. Nutritional deficiency symptoms were observed from 25 DAP, when no fertilizer was used. The permanence time in trays may be extended if the slow-release fertilizer is used.

Agronomic performance and selection of sweet-potato genotypes grown from seeds

The low availability of varieties adapted to different crop regions, mainly regarding edaphoclimatic conditions, is one of the causes of low sweet-potato crop yields. The objective of this work was to evaluate agronomic characteristics of sweet-potato plants, from the crossing between the genotypes Londrina and Uruguaiana, grown in the region of Presidente Prudente, SP, Brazil, to select materials with high commercial yield and desirable tuberous root shape and color. The natural crossing between the genotypes Londrina and Uruguaiana grown in alternating rows resulted in 2,430 potentially viable seeds. These seeds were used for growing seedlings whose vines were grown in the field for selecting genotypes with desirable characteristics. The results showed a high diversity in skin and flesh colors; number of tuberous roots per plant, shape, fresh and dry weights, and total and commercial yields of tuberous roots. The selected genotypes were then evaluated in three experiments. Several genotypes presented higher commercial yield than their parents. Three genotypes were approved as cultivars by presenting superior agronomic characteristics than their parents.The low availability of varieties adapted to different crop regions, mainly regarding edaphoclimatic conditions, is one of the causes of low sweet-potato crop yields. The objective of this work was to evaluate agronomic characteristics of sweet-potato plants, from the crossing between the genotypes Londrina and Uruguaiana, grown in the region of Presidente Prudente, SP, Brazil, to select materials with high commercial yield and desirable tuberous root shape and color. The natural crossing between the genotypes Londrina and Uruguaiana grown in alternating rows resulted in 2,430 potentially viable seeds. These seeds were used for growing seedlings whose vines were grown in the field for selecting genotypes with desirable characteristics. The results showed a high diversity in skin and flesh colors; number of tuberous roots per plant, shape, fresh and dry weights, and total and commercial yields of tuberous roots. The selected genotypes were then evaluated in three experiments. Several genotypes presented higher commercial yield than their parents. Three genotypes were approved as cultivars by presenting superior agronomic characteristics than their parents

Cultivo de melancia em áreas de renovação de canavial sob diferentes manejos do solo

The objective of this work was to evaluate watermelon (Citrullus lanatus) cultivation in regeneration areas of a sugarcane field, under different soil management systems and N fertilization regimes. Two experiments were carried out in the 2014/2015 and 2015/2016 harvest seasons, in areas of sugarcane plantation in Andradina, in the state of São Paulo, Brazil. Cultivations were performed in a randomized complete block design, with plots and subplots, and four replicates. The plots represented the tillage systems (conventional, minimum tillage, and no-tillage), and the subplots, the different N fertilization rates (0, 100, 200, and 300 kg ha-1) applied as topdressing. In 2014/2015, the minimum tillage system resulted in the highest commercial yield of 70.2 Mg ha-1. In 2015/2016, there were no differences for yield among tillage systems; however, yield differed among N treatments. The highest commercial yields of 64.1 and 31.1 Mg ha-1 were achieved with the N doses of 253 and 209 kg ha-1 as topdressing, respectively, in 2014/2015 and 2015/2016. Watermelon can be cultivated in regeneration areas of sugarcane field, and the demand of N by the plant does not depend on the soil tillage system.O objetivo deste trabalho foi avaliar o cultivo de melancia (Citrullus lanatus) em áreas de renovação de canavial, em diferentes sistemas de preparo do solo e adubação nitrogenada. Foram realizados dois experimentos nas safras de 2014/2015 e 2015/2016, em áreas de plantio de cana-de-açúcar, em Andradina, no Estado de São Paulo, Brasil. Os cultivos foram feitos em delineamento experimental de blocos ao acaso, com parcelas, subparcelas e quatro repetições. As parcelas representaram os sistemas de preparo do solo (plantio convencional, cultivo mínimo e plantio direto), e as subparcelas, as diferentes doses de N aplicadas em cobertura (0, 100, 200 e 300 kg ha-1). Em 2014/2015, o cultivo mínimo apresentou a maior produtividade comercial de 70,2 Mg ha-1. Em 2015/2016, não houve diferenças quanto à produção entre os tratamentos de preparo de solo; porém, a produção diferiu entre os tratamentos com N. As maiores produtividades comerciais de 64,1 e 31,1 Mg ha-1 foram obtidas com as doses de 253 e 209 kg ha-1 de N em cobertura, respectivamente, em 2014/2015 e 2015/2016. A melancia pode ser cultivada em áreas de renovação de canavial, e a demanda de N pela planta não depende do sistema de preparo de solo

Desempenho agronômico e uso eficiente da terra em arranjos de plantas de mandioca e batata-doce

RESUMO O consórcio de duas ou mais culturas pode representar melhor uso do solo, alternativa para redução de perdas e incremento de renda. Assim, objetivou-se, com este trabalho, avaliar o desempenho agronômico de mandioca e batata-doce, consorciadas em diferentes arranjos, e determinar o índice de uso eficiente da terra (UET). O delineamento experimental foi em blocos ao acaso, com cinco tratamentos e cinco repetições. Os tratamentos foram: M (monocultivo de mandioca); 2M:1B (consórcio composto por duas leiras de mandioca alternadas com uma leira de batata-doce); 1M:1B (consórcio composto por leiras alternadas de mandioca e batata-doce); 1M:2B (consórcio composto por uma leira de mandioca alternada com duas leiras de batata-doce) e B (monocultivo de batata-doce). Cada parcela experimental foi constituída por seis ou oito fileiras de 7 m de comprimento, espaçadas de 0,9 m entre si, separadas por uma faixa de circulação de 2,0 m. Foram avaliados a produtividade comercial, a massa da matéria fresca individual, o comprimento, o diâmetro e a massa seca de raízes, sendo esses valores comparados pelo teste de Tukey (p<0,05). As maiores produtividades da mandioca ocorreram quando cultivada em M e 2M:1B, enquanto a maior produtividade de batata-doce foi em B. Os tratamentos estudados não apresentaram diferença significativa para massa da matéria fresca individual, comprimento, diâmetro e matéria seca de raiz de mandioca. Na batata-doce, o tratamento 1M:2B resultou em menor valor de massa da matéria fresca individual e de diâmetro de raiz. Constatou-se também vantagem do consórcio sobre o monocultivo, visto que todos os arranjos de consórcio promoveram valor de UET superior a 1. Logo, o consórcio entre mandioca e batata-doce resulta em melhor aproveitamento dos recursos ambientais, comparado com o monocultivo

Sweet potato yield and physical and chemical properties of soil in function of organic and mineral fertilizers

A batata-doce geralmente é cultivada com baixos investimentos em adubação, todavia a cultura pode apresentar significativo incremento de produtividade quando é realizada adubação adequada ao seu cultivo. Neste trabalho objetivou-se avaliar a influência do uso de fontes e doses de fertilizantes na produtividade da cultura da batata-doce e em propriedades físicas e químicas do solo. O delineamento experimental foi em blocos ao acaso, no esquema fatorial 3x5, com três repetições. Os tratamentos do experimento foram constituídos por fontes de fertilizante (esterco de galinha, fertilizante mineral com composição química equivalente aos nutrientes encontrados nas doses de esterco de galinha e adubação combinada de esterco de galinha (50%) com adubo mineral (50%) com somatório de nutrientes equivalente aos nutrientes encontrados nas doses de esterco de galinha) e doses de fertilizante (equivalentes a 0, 3, 6, 9 e 12 t ha-1 de esterco de galinha). Como resultado do trabalho, verificou-se que a cultura responde à adubação do solo, com acréscimos de produtividades total e comercial com a utilização de esterco de galinha, fertilizantes minerais e a combinação de ambos até as doses aproximadas de 5,8; 6,5 e 7,0 t ha-1, respectivamente. A adubação com esterco de galinha, isolada ou combinada com adubo mineral, promove as maiores produtividades. Não há diferença na densidade do solo e na porosidade total em função de fontes de fertilizantes ou doses utilizadas. A adição dos fertilizantes promove acréscimos nos valores de pH e nos teores de matéria orgânica, P, K, Ca e Mg do solo em relação ao solo sem adição de fertilizantes.Sweet potato crop is usually cultivated with low fertilization investments, but the crop can present significant yield increase when correct fertilization is carried out in its cultivation. In this study aimed to evaluate the influence of the use of different fertilizer sources and doses on sweet potato yield and on physical and chemical properties of soil. The experimental design was a randomized block in 3x5 factorial scheme, with three replications. The treatments were composed of fertilizer sources (chicken manure, mineral fertilizer with chemical composition equivalent to the nutrients found in chicken manure and blend of chicken manure (50%) with mineral fertilizer (50%) equivalent to the sum of nutrients found in chicken manure) and fertilizer doses (nutrients equivalent to 0, 8, 16 and 24 t ha-1 of chicken manure). As result of study, it was found that the crop responds to soil fertilization with increases in total and commercial yields with the use of chicken manure, mineral fertilizers and the combination of both until the doses of 5.8, 6.5 and 7.0 t ha-1, respectively. Fertilization with chicken manure, alone or in combination with chemical fertilizers, promotes highest yields. There is no difference in soil bulk density and in total soil porosity as a function of fertilizer sources or doses. The addition of fertilizer promotes increases in pH and organic matter, P, K, Ca and Mg levels in the soil in relation to soil without fertilizer.

Use of slow-release fertilizer on the production of sweet potatoes plantlets in tray

The production of plantlets in containers generally requires the use of fertilizers. The aim of this study was to evaluate the production of sweet potato in styrofoam trays using slow-release fertilizer. The experiment was carried out, under a screen-protected nursery, in a factorial scheme 5x5, with five doses of slow-release fertilizer NPK 19-06-10 (0, 50, 100, 150 e 200 g per 25 kg de substrate) and five times of plantlets permanence in tray (14, 28, 42, 56 and 70 days after planting the cuttings). The number and dry matter of roots and leaves were evaluated. The number of roots was not influenced by fertilizer addition. In general, there is not damage to plantlets growth until the highest dose used. Therefore, the fertilizer addition increases the sweet potato plants growth and the dose of 200 g per 25 kg of substrate is responsible for the best results