The 'Montenegrina' mandarin ( Citrus deliciosa Tenore) is widely cultivated in southern Brazil. This cultivar has a great tendency for alternate bearing, requiring thining of the fruit. However, the chemical thinners studied until now in this cultivar have not been successful. The objective of this research was to evaluate the effect of 3,5,6-trichloro-2-pyridinyloxyacetic acid (3,5,6-TPA) on the production and fruit quality of the 'Montenegrina' mandarin, in comparison with hand thinning and the options of chemical thinning previously studied. Hand thinning and no thinning were used as controls. Ethephon was applied in three doses: 200mg L-1, 300mg L-1 or 200mg L-1 + 3% urea; or 3,5,6-TPA, in four doses: 10, 20, 30 or 40mg L-1. Fruits of the hand thinned trees and those treated with 40mg L-1 showed greater average size, greater distribution of commercial caliber and more orange colors. No treatment reduced alternate bearing. Applications of 40mg L-1 of 3,5,6-TPA as a chemical thinner, during the physiological drop of young fruit, had a similar effect that of hand thinning over yield and quality of fruits of 'Montenegrina' mandarin.

Brazil is the second world largest citrus producer, and the State of Rio Grande do Sul (RS) is the sixth largest national producer, with about 505 thousand tons of citrus fruits in 2014. The state's citrus chain has different characteristics, consisting mostly of small family-based farms. This study aimed to diagnose the production system used in Rio Grande do Sul, through a structured questionnaire composed of 19 questions of closed and open answers to 163 growers, residents in 35 locations in the RS, belonging to the regions Vales do Caí and Taquari, Alto Taquari, Alto Uruguai, Noroeste, Serra do Nordeste and Fronteira Oeste. The selected locations have the citrus industry as an important activity for the local economy and the number of interviewed farmers varied according to the existing cultivated area in each. The interviewed farmers in each city were selected by non-probability sampling and convenience, and the information obtained was planned, generating quantitative and qualitative data. There were features prevalent in the visited farms, such as aging of the rural population, low level of education of growers, mainly family labor employment and concern about the shortage of work observed in rural areas. However, they presented long experience in the citrus activity and obtain good yields, similar to the average recorded in the State. Index terms: citrus, diagnosis, family farming. Caracterização do sistema de produção em propriedades citrícolas do Rio Grande do Sul RESUMO O Brasil é o segundo maior produtor mundial de citros, sendo o Rio Grande do Sul (RS) o sexto maior produtor nacional, com cerca de 505 mil toneladas de frutas cítricas em 2014. A cadeia citrícola gaúcha possui características diferenciadas, constituída em sua maioria por pequenas propriedades de base familiar. O presente estudo objetivou a realização de um diagnóstico do sistema produtivo por meio da aplicação de questionário estruturado composto por 19 questões de

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The objective of this study was to evaluate the performance of six rootstocks on vegetative growth, production and fruit quality of Lee tangelo for eleven growing seasons in Butiá, Rio Grande do Sul, Brazil. The evaluated rootstocks were: Swingle citrumelo, Caipira sweet orange, Troyer citrange, Rangpur lime, Volkamer lemon and Flying Dragon trifoliate orange. Trees grafted on Flying Dragon trifoliate orange and Volkamer lemon developed small canopy of spheroidal shape, while on the other rootstocks the canopy shape was ellipsoid. Fruit quality of Lee tangelo on all rootstocks was commercially appropriate, however the trees grafted on Volkamer lemon and Rangpur lime produced fruits with lower internal quality. Flying Dragon trifoliate orange and Volkamer lemon increased yield efficiency of the scion. The best yields for Lee tangelo was obtained on the Troyer citrange, Caipira sweet orange, Swingle citrumelo and Rangpur lime. Index terms: fruit yield, fruit quality, tree size, alternate bearing, alternaria brown spot. Performance horticultural do tangeleirro Lee enxertado em seis porta-enxertos no Sul do Brasil RESUMO O objetivo deste estudo foi avaliar o desempenho de seis porta-enxertos no crescimento vegetativo, produção e qualidade do fruto de tangeleiro Lee, por onze anos agrícolas em Butiá, Rio Grande do Sul, Brasil. Os porta-enxertos avaliados foram: citrumeleiro Swingle, laranjeira doce Caipira, citrangeiro Troyer, limoeiro Cravo, limoeiro Volkameriano e trifoliateiro Flying Dragon. As plantas enxertadas em Flying Dragon e em limoeiro Volkameriano desenvolveram copa pequena de formato esferoidal, enquanto que nos outros porta-enxertos o formato da copa foi a elipsoide. A qualidade dos frutos de tangeleiro Lee, em todos os porta-enxertos, foi classificada como comercialmente apropriada, no entanto, as plantas enxertanos limoeiros Volkameriano e Cravo produziram frutas com menor qualidade. Os porta-enxertos Flying Dragon e Volkameriano