RESUMO O mercado brasileiro de processamento de batata tem mostrado expressivo crescimento nos últimos anos. No entanto, sua expansão é condicionada pelo suprimento de matéria-prima adequada ao processamento industrial. A escolha correta da cultivar contribui para a redução do custo de produção e para o aumento do rendimento e da qualidade do produto final. O objetivo da pesquisa foi estudar a eficiência produtiva de cultivares de batata recém introduzidas no Brasil e a qualidade para fritura na forma de batata-palha e chips. Foram avaliadas nove cultivares de batata (Arizona, Caruso, Destiny, Excelence, Saviola, Agata, Almera, Fontane e Markies) em ensaio conduzido entre janeiro e maio de 2013, na região sudoeste de Minas Gerais. As cultivares Arizona e Caruso exibiram maior potencial produtivo e, juntamente com 'Markies', a maior produção de tubérculos comerciáveis. 'Caruso' e 'Destiny' produziram mais de 20% de massa seca e baixos teores de açúcares redutores. 'Caruso' mostrou o maior rendimento de fritura em ambas as formas de processamento e absorveu menos gordura na forma de palha. 'Destiny' absorveu menos gordura como chips. 'Excelence' apresentou desempenho intermediário em todos os atributos avaliados. 'Caruso', 'Destiny' e 'Excelence' produziram chips com cor adequada ao mercado. Entre as cultivares avaliadas, 'Caruso', 'Destiny' e 'Excelence' foram as mais promissoras e se apresentaram apropriadas ao processamento na forma de batata-palha e 'Destiny' pode ser indicada também para o processamento de chips.

ABSTRACT Brazilian market of potato processing has presented expressive development in recent years. However, its expansion is constrained by raw material supply suitable for industrial processing. Selection of adequate cultivars contributes to final product cost reduction as well as its yield and quality improvement. The research aimed to study tuber yield and evaluate its frying potential for shoestrings and chips, of potato cultivars recently introduced in Brazil. Nine potato cultivars (Arizona, Caruso, Destiny, Excelence, Saviola, Agata, Almera, Fontane and Markies) were assessed in an experiment carried out between January and May, 2013, in South-West region of Minas Gerais State, Brazil. 'Arizona' and 'Caruso' cultivars exhibited superior productive potential and along with 'Markies' the highest production of marketable tubers. 'Caruso' and 'Destiny' produced more than 20% of dry matter and the lowest reducing sugar levels. 'Caruso' exhibited the highest frying yield in both processing shapes and absorbed less fat as shoestring. 'Destiny' absorbed less fat when processed as chips. 'Excelence' presented intermediary performance for every evaluated attribute. 'Caruso', 'Destiny', and 'Excelence' produced chips with appropriate color for market. Among the assessed cultivars, 'Caruso', 'Destiny', and 'Excelence' were the most promising. These cultivars demonstrated appropriate processing ability in the shape of shoestrings. 'Destiny' could also be indicated to be processed as chips.

Three field experiments were carried out to assess the level of resistance of several cultivars to early blight (EB) and to examine the association between host resistance and either foliage maturity or tuber skin types. A total of 26 cultivars were used in Exps. 1 and 2, and 24 in Exp. 3. Plants were inoculated with isolates of Alternaria grandis at 31 days after planting. EB severity was quantified in each plot every seven days. The approach to determine the resistance levels of potato cultivars was based on multivariate analysis techniques. The tested cultivars responded as either resistant, moderately resistant, moderately susceptible or susceptible to EB. Most of the cultivars were classified as susceptible or moderately susceptible to EB. Resistant cultivars were mid-season, mid-late or late maturity. None of the susceptible cultivars were later maturity (mid-late or late maturity). In most cases, susceptible cultivars were earlier maturity (early or mid-early maturity). Most resistant cultivars had rough, mid-rough or smooth skin. None of the susceptible cultivars had rough skin. In most cases, susceptible or moderately susceptible cultivars had smooth skin. Obtaining potato cultivars that are resistant to this destructive disease will help reduce production costs and the need for costly fungicides.

Neste trabalho estudou-se o efeito dos fitorreguladores Ga3 e Paclobutrazol no florescimento e produção de frutos de morangueiro (Fragaria x ananassa Duch.). O experimento foi conduzido em Caldas (MG), na EPAMIG. O delineamento experimental adotado foi o de blocos casualizados, com quatro repetições, num esquema fatorial 2x4, onde as variáveis dependentes foram duas cultivares ('Oso Grande' e 'Seascape') e os tratamentos controle (água); GA3 a 40 mg L-1 em duas aplicações (aos 45 e 65 dias após o transplante); paclobutrazol (produto comercial Cultar 10%) a 100 mg L-1 aos 75 dias após o transplante das mudas; combinação de GA3 + paclobutrazol aplicados aos 45; 65 e aos 75 dias, respectivamente, após o transplante. Os tratamentos foram aplicados via foliar em ambas as cultivares. A resposta à aplicação dos fitorreguladores GA3 e paclobutrazol em morangueiro depende da cultivar. A cv. Seascape, de dia neutro, respondeu melhor à aplicação de GA3 que a 'Oso Grande', de dia curto; Por outro lado, o paclobutrazol, quando aplicado via foliar, aos 75 dias após o transplante, reduziu o florescimento do morangueiro o que mostra a necessidade de mais pesquisas sobre dosagens e épocas de aplicação do paclobutrazol nesta cultura.

The effect of bioregulators GA3 and paclobutrazol was evaluated on flowering and yield of strawberry cultivars Oso Grande and Seascape. The experiment was carried out in Caldas, Minas Gerais State, Brazil. The treatments consisted of control (no application of bioregulators); GA3 at 40 mg L-1, in two applications (45 and 65 days after transplanting date); paclobutrazol (commercial product Cultar, 10%) at 100 mg L-1, 75 days after transplanting date; combination of GA3 + paclobutrazol, applied 45; 65 and 75 days, respectively, after transplanting date. The experimental design was a randomized complete block, with four replications, in a factorial 2x4. The response to the bioregulators GA3 and Paclobutrazol was cultivar dependent. 'Seascape', a day neutral cultivar, presented better results in relation to application of GA3 than 'Oso Grande', a short-day cultivar. Paclobutrazol applied 75 days after transplanting date reduced the flowering.